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ROLE OF C REACTIVE PROTEIN AND WBC COUNT IN THE DIAGNOSIS OF ACUTE APPENDICITIS AND ITS PREDICTIVE
VALUE IN ASSESSING THE SEVERITY OF THE DISEASE
Dissertation submitted to the
THE TAMILNADU DR.M.G.R. MEDICAL UNIVERSITY
In partial fulfilment of the requirements for the degree of M.S. GENERAL SURGERY – BRANCH I
DEPARTMENT OF GENERAL SURGERY THANJAVUR GOVERNMENT MEDICAL COLLEGE AND
HOSPITAL
SEPTEMBER, 2015
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DECLARATION
I solemnly declare that this Dissertation “ROLE OF C REACTIVE PROTEIN AND WBC COUNT IN THE DIAGNOSIS OF ACUTE APPENDICITIS AND ITS PREDICTIVE VALUE IN ASSESSING THE SEVERITY OF THE DISEASE “ was done by me in the Department of General Surgery, Thanjavur Medical College, and Hospital , Thanjavur under the Guidance and Supervision of my Professor Dr.K .MAHADEVAN M.S. Department of General Surgery, Thanjavur Medical College, Thanjavur between 2013 and 2016.
This Dissertation is submitted to The Tamilnadu Dr. M.G.R Medical University , Chennai in partial fulfilment of University requirements for the award of M.S Degree ( GENERAL SURGERY).
DR.KAUSHIK,J Postgraduate Student, Thanjavur Medical College.
Thanjavur.
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CERTIFICATE BY THE GUIDE
This is to certify that this dissertation titled “ ROLE OF C REACTIVE PROTEIN AND WBC COUNT IN THE DIAGNOSIS OF ACUTE APPENDICITIS AND ITS PREDICTIVE VALUE IN ASSESSING THE SEVERITY OF THE DISEASE “ is a bonafide research work done by Dr. KAUSHIK. J, in partial fulfilment of the requirement for the degree of M.S. GENERAL SURGERY – BRANCH I.
Dr. K. Mahadevan M.S., Professor
Dept. of General Surgery Thanjavur Medical College and Hospital
(Guide)Date : Place :
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CERTIFICATE
This is to certify that the dissertation titled “ ROLE OF C REACTIVE PROTEIN AND WBC COUNT IN THE DIAGNOSIS OF ACUTE APPENDICITIS AND ITS PREDICTIVE VALUE IN ASSESSING THE SEVERITY OF THE DISEASE “ is a bonafide research work done by Dr. Kaushik.J. under the guidance of Dr. K. Mahadevan M.S., ( Professor, Department of General Surgery) Thanjavur Government Medical College Hospital, Thanjavur.
Dr.M. SINGARAVELU, M.D,DCH, Dr.M.ELANGOVAN M.S., The Dean, The Professor and HOD, Thanjavur Medical College, Department of General surgery, Thanjavur – 613004. Thanjavur Medical College, Thanjavur – 613004.
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ACKNOWLEDGEMENT
I am grateful to Dr. SINGARAVELU M.D., Dean for giving me permission and opportunity to conduct study and data collection at Thanjavur Medical College and Hospital.
I am deeply grateful to my professor and Head of the Department of General Surgery , Prof. Dr. ELANGOVAN.M. M.S.,for his encouragement and suggestions in preparing this work.
I owe my sincere and grateful acknowledgement to my beloved chief, teacher and guide Prof. Dr. K. MAHADEVEN M.S., Professor of General Surgery who inspired me to take this topic of “ ROLE OF C REACTIVE PROTEIN AND WBC COUNT IN THE DIAGNOSIS OF ACUTE APPENDICITIS AND ITS PREDICTIVE VALUE IN ASSESSING THE SEVERITY OF THE DISEASE“. I extend my grateful acknowledgement to my teachers, Dr. MUTHUVINAYAGAM M.S., Asst. Prof. of General Surgery and Dr. MARIMUTHU M.S., Asst. Prof. of General Surgery.
I express my gratitude and sincere acknowledgement for the help and support extended to me by anaesthetists, staff nurses, Staff, in Dept of Biochemistry and Pathology and other faculty members. I mention my wife Dr. Deepika for being my wings of support throughout the thesis.
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I wish to express my whole hearted thanks to all the patients who participated in the study. Completion of this work would not have been possible without their co- operation. And most of all I would like to thank my friends for their tireless efforts, guidance, and patience in helping me to finish the study.
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LIST OF ABBREVIATIONS USED
CRP C - Reactive Protein
UCAA Uncomplicated Acute Appendicitis CAA Complicated Acute Appendicitis
TC Total white cell count
DC Differential White Cell Count
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TABLE OF CONTENTS
Sl. No. Page No.
1. INTRODUCTION 1
2. AIMS AND OBJECTIVES 4
3. HISTORICAL ASPECTS 5
4. REVIEW OF LITERATURE8
4.1. ANATOMY 9
4.2. PHYSIOLOGY 11
4.3. INCIDENCE 12
4.4. AETIOLOGY 12
4.5. PATHOGENESIS 12
4.6. BACTERIOLOGY 13
4.7. CLINICAL FEATURES 13
4.8. DIAGNOSIS IN SPECIAL POPULATION 16
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4.9. DIFFERENTIAL DIAGNOSIS 19
4.10. INVESTIGATIONS 21
4.11. MANAGEMENT 26
4.12. COMPLICATIONS 40
4.13. C- REACTIVE PROTEIN 45
5. MATERIALS AND METHODS 46
5.1. SOURCE OF DATA
5.2. TYPE OF STUDY
5.3. NUMBER OF GROUPS STUDIES
5.4. SAMPLE SIZE
5.5. INCLUSION CRITERIA
5.6. EXCLUSION CRITERIA
5.7. PARAMETERS STUDIED
5.8. PROCEDURE
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5.9. METHOD OF STATISTICAL ANALYSIS
5.10. ETHICAL CONSIDERATIONS
6. RESULTS 50
7. DISCUSSION 67
8. SUMMARY 73
9. CONCLUSION 75
10. BIBLIOGRAPHY
11. ANNEXURES
11.1. CONSENT FORM
11.2. PROFORMA
11.3. MASTER CHART
11.4. KEY TO MASTER CHART
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LIST OF TABLES
Serial
No Tables Page No
1 Histopathological group 51
2 Sex of study subject 52
3 Age of study subjects 53
4 Association between Uncomplicated acute appendicitis and complicated acute appendicitis with signs and symptoms
55 5 Comparison of age, white cell count and CRP 58
6 Association between CRP levels 59
7 Positive and negative CRP levels in CAA and UCAA 60
8 Area under curve for CRP values 62
9 Sensitivity and Specificity of CRP 62
10 Area under curve for white cell count 63
11 Total count values in CAA and UCAA 64
12 Sensitivity and Specificity for white cell count 64
13 Area under curve for Polymorph percentage 65
14 Polymorph values in CAA and UCAA 66
15 Sensitivity and Specificity for Polymorph percentage 66
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LIST OF FIGURES
Serial No
FIGURES Page No
1 Anatomy of appendix 10
2 Histology of appendix 11
3 Diagram showing MC Burney’s point 15
4 CT image of appendicitis 25
5 Uncomplicated acute appendicitis 42
6 Uncomplicated acute appendicitis 43
7 Laparoscopic appendicectomy 43
8 Complicated acute appendicitis 44
9 Histopathological group 51
10 Sex of study subject 53
11 Age of study subjects 54
12 Signs and symptoms in Uncomplicated acute appendicitis and complicated acute appendicitis
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13 Association between CRP levels 60
14 Positive and negative CRP levels in CAA and UCAA 61
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CHAPTER 1 INTRODUCTION
Acute appendicitis is one of the most common surgical conditions in patients with right lower quadrant pain. It is the most common cause of infection in community- acquired intra-abdominal infections [1, 2, 3].
Incidence is 42-175 in 100,000 persons. The diagnosis is usually made on the basis of clinical findings such as fever, right lower quadrant pain, tenderness and muscle guarding [4]. The perforation rate is high, [5] The accuracy of clinically based diagnoses depends on clinician experience and has been reported to range from 71% to 97% [6].
Thus, accurate diagnosis of acute appendicitis is still difficult [7, 8, 9]. Worldwide perforated appendicitis is the leading general surgical cause of death [10].
Blood inflammatory markers such as white blood cell (WBC) counts and C- reactive protein (CRP) levels are performed in patients suspected of having acute appendicitis. The importance of these blood inflammatory markers in the context of deciding upon discharge or admission for further investigation has been stressed [11-16]
The treatment of appendicitis has been primarily surgery. However, for those who present with catarrhalis appendicitis (inflammation within the mucous membrane), or phlegmnous appendicitis, initial treatment by non-surgical management has been shown to be safe and effective [17, 18]. However complicated appendicitis such as gangrenous appendicitis is treated with emergency surgery [19].
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CRP is a non-specific inflammatory marker used routinely as an aid in the diagnosis of patients with an acute abdomen [20, 21] in some centres. It is an acute phase protein and is produced in the liver. Normal serum concentration is less than 10 mg/l 8–
12 hours after infection or trauma. CRP synthesis is controlled by Interleukin-6 and in a few minutes, it increases to 1,000 times. CRP is increased in infections, autoimmune disorders, inflammatory arthritis, neoplasia, and aging [20, 22, 23, 24, 25v]. Some reports show that these inflammatory markers have low diagnostic accuracy in acute appendicitis [26, 27, 28]. However some articles conclude that WBC counts and CRP levels are reliable indicators of disease severity and that they are significantly correlated with pathological findings [29]. Some reports indicated that appendicitis is unlikely, when the white blood cells count and CRP value are normal [30].
Because of its atypical symptoms and difficulties in making a definite diagnosis, only 84% of the patients who undergo an appendectomy manifest pathological findings of appendicitis. The number of negative appendicectomies is high. Negative appendicectomies are one of the burdens faced not only by the general surgeon but also the patient and the society as a whole, since appendectomy, results in socio-economic impacts in the form of declined productivity and loss of working days. In perforated or gangrenous appendicitis due to the delay of operation, the cost, the hospital stay and the incidence of early and delayed complications are drastically increased. Therefore, early detection and proper treatment of appendicitis is required to minimize postoperative complication [31].
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The investigations for early detection of complicated appendicitis are still limited.
Currently, the diagnosis of complicated appendicitis depends on the onset of symptoms and physical examination; thus, inaccuracy due to subjective interpretation is common.
This increases the need of a test that will help in the diagnosis of acute appendicitis and predict the severity of the disease.
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CHAPTER 2
AIMS & OBJECTIVES
AIMS:
To assess the role of C-reactive protein and white cell count in the diagnosis of acute appendicitis and its predictive value in assessing the severity of the disease.
OBJECTIVES:
1. To study the value of preoperative C - reactive protein and WBC count in diagnosing acute appendicitis.
2. To correlate its value in grading of Acute Appendicitis as compared to Histo- pathological reports.
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CHAPTER 3
HISTORICAL ASPECTS
ACUTE APPENDICITIS:
1736 – First appendicectomy was performed by Claudius Amyand, Surgeon to Westminster and St.George’s Hospitals and Sergeant Surgeon to George II. He operated on a boy of 11 years age who had a right scrotal hernia with fistula, within the scrotum was found the appendix perforated by a pin.
1755 – Heister recognised that the appendix be the site of acute primary inflammation during autopsy on the body of a criminal.
1824 – Loyer Villermany presented “Observations of use in the inflammatory conditions of the cecal appendix” in Royal Academy of Medicine in Paris – two examples of acute
appendicitis leading to death.
1827 – Hunson and Donice, 1830 – Goldbeck, 1835 – Duputryne – developed the concept of Inflammation arising in the cellular tissue surrounding the cecum – perityphlitis.
1839 – Bright and Addison released the first text book that described symptoms that accompanied inflammation and perforation of appendix.
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1886 – Fitz, Professor of Medicine, Harvard gave description of clinical features and pathological changes of the disease and was the first to use the term appendicitis.(32) 1848 – Is the year evolution of operative treatment of appendicitis started – Hancock, in London drained an appendicular abscess.
1867 – Parker of New York described earlier incision of appendicular abscess.
1886 – Kronlein first published account of appendicectomy performed on a 17 years male who died after 2 days.
1887 – Chester Mc Burney in New York described characteristic migratory pain and localization of pain along line joining anterior superior iliac spine and umbilicus. He insisted early diagnosis and early operative intervention in acute appendicitis.
1894- Mc Burney devised right lower quadrant muscle splitting incision. (33) 1950 – Introduction of antibiotics in the treatment of acute appendicitis resulted in reduction of morbidity and mortality.
1982-Laparoscopic appendicectomy was first reported by Kurt Semm
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C-REACTIVE PROTEIN:
1930 – Tillet and Francis identified CRP and it is regarded as the acute phase protein [34]
1983 – Pepys and Baltz published “CRP is a reliable indicator of inflammation or injury
“[35]
2003 - Mustard et al. documented that serial postoperative CRP levels could predict septic complications before their clinical manifestation. [36]
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CHAPTER 4
REVIEW OF LITERATURE
4.1. ANATOMY 4.2. PHYSIOLOGY 4.3. INCIDENCE 4.4. AETIOLOGY 4.5. PATHOGENESIS 4.6. BACTERIOLOGY
4.7. CLINICAL FEATURES
4.8. DIAGNOSIS IN DIFFICULT CIRCUMSTANCES 4.9. DIFFERENTIAL DIAGNOSIS
4.10. INVESTIGATIONS 4.11. MANAGEMENT 4.12. COMPLICATIONS
4.13. C - REACTIVE PROTEIN
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4.1. ANATOMY
The appendix is commonly described as Vermiform Appendix, in Latin Vermin means wormlike. It is a blind diverticulum of about 6-10 cms. in length from the intestines and it contains masses of lymphoid tissue. Its origin is from the posteromedial aspect of the cecum inferior to the ileocecal junction. The appendix has got a short mesoappendix which is a short triangular mesentery of appendix attached to the cecum and proximal part of the appendix. The appendix first appears at the 8th week of gestation as an outpouching from caecum and gradually rotates to a medial location as the gut rotataes and becomes fixed to right lower quadrant. The appendix is described as retrocecal, pelvic, subcecal, preileal or right pericolic depending on the position of the tip of the appendix but the relationship between the base of the appendix and the cecum remains constant. The most common position is retrocaecal. The convergence of the taenia coli at the junction of the cecum with the appendix is a useful landmark to identify the appendix. [37, 38, 39, 10 ].
The appendix is supplied by the appendicular artery, a branch of the ileocolic artery and the venous drainage is in to the superior mesenteric vein through the ileo colic vein. Lymphatic drainage is into the lymph nodes in the mesoappendix and the ileocolic lymphnodes. Efferent lymph vessels form the ileocolic nodes drain into the superior mesenteric lymphnodes.
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The sympathetic and parasympathetic nerves from the superior mesenteric plexus supply the appendix. From the lower thoracic part of the spinal cord the sympathetic fibres originate and the parasympathetic nerve fibres are derived from the vagus nerves.
FIG 1.ANATOMY OF APPENDIX
Histological examination of appendix shows goblet cells scattered throughout mucosa. The submucosa contains lymphoid follicles.
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FIG 2.HISTOLOGY OF APPENDIX
4.2. PHYSIOLOGY
Previously for a long time appendix was erroneously viewed as a vestigial organ with no known function but now it is a well recognised immunologic organ that actively participate in the secretion of immunoglobulins, particularly immunoglobulin A. A potential relationship has been now attached between appendectomy and development of inflammatory bowel diseases. Radford Smith (2002) stated that “Appendectomy may protect against the subsequent development of inflammatory bowel disease, however the mechanism is unclear”. [40]
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4.3. INCIDENCE
Appendicitis is one of the most common causes of abdominal emergencies and accounts for 1% of all surgeries [41]. Though rare in infants, it becomes increasingly common through the ages of 10-30 years. After 30 years, the incidence declines among teenagers and adults the male to female ratio is about 3:2. After the age of 25 years the ratio declines until it is equal by mid 30s [42].
4.4. AETIOLOGY
Obstruction of the lumen is the dominant etiologic factor in acute appendicitis.
This may be caused by inspissated stool (fecolith/appendicolith), lymphoid hyperplasia, vegetable matter or seeds, parasites, neoplasm. Presence of fecolith is the most common cause of appendiceal obstruction [10].
4.5. PATHOGENESIS
The lumen of appendix is small in relation to its length and this configuration may predispose to closed loop obstruction. When the appendiceal lumen is blocked the intraluminal pressure increases upto 60cms of water due to continued mucus secretion.
This leads to elevated pressure in the appendiceal wall and results in localised perfusion defects which leads to loss of mucosal integrity and subsequent bacterial invasion. This leads to necrosis of appendiceal wall and perforation of appendix. If this progresses slowly and diagnosis is delayed, an abscess can result due to walling off of the
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inflammatory process by the adjacent organs and omentum. If this progression is much faster it leads to gangrene and this leads to free perforation into peritoneal cavity.
Perforation and abscess formation may also lead to fistula formation to adjacent organs [43].
4.6. BACTERIOLOGY
Normal appendicular flora is similar to normal colonic flora and remains constant throughout life with the exception of Porphyromonas gingivalis which is seen only in adults. Escherichia coli and Bacteroids fragilis are the commonest organisms seen in the normal appendix, acute appendicitis and in perforated appendix [44, 45, 46]. Upto a maximum of 14 organisms have been isolated in complicated acute appendicitis with perforation clearly showing that acute appendicitis is a polymicrobial infection.
Prophylaxis with antibiotics reduces the incidence of postoperative wound infection and intra abdominal abscess. In uncomplicated acute appendicitis antibiotic is given for a period of 24 to 48 hours and in cases of complicated acute appendicitis 7 to 10 days of antibiotic coverage is a must [47].
4.7. CLINICAL FEATURES
The most common cause of abdominal pain which is surgically correctable is acute appendicitis but the diagnosis remains difficult in many instances. Some of the signs and symptoms may not be present in all instances. An early diagnosis is essential, as a delay in diagnosis may lead to gangrene and perforation. This increases morbidity
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and mortality significantly while on the other hand an incorrect diagnosis leads to an unnecessary surgery, although not catastrophic, often subjects these patients to an unnecessary operation.
During development appendix is formed as a midline structure, so the classic presentation is pain that starts in the region of the umbilicus and then migrates to the right iliac fossa. This is due to localised peritoneal inflammation which occurs approximately within 24 hrs. Migratory pain is present only in 70% of cases and rest of the patients have discomfort in right lower quadrant. Cough, or increase in intra abdominal pressure due to movement or valsalva manoeuvre worsens this pain. 75% of cases present with vomiting and anorexia always accompanies appendicitis. Obstipation or diarrhoea is present in few cases. Low grade fever up to 101*F (38.3*C) may be present.
Physical findings depends on the anatomic position of the inflamed appendix is and whether the organ has already ruptured or not. In uncomplicated acute appendicitis vital signs are minimally changed, temperature elevation is rarely > 1* C and the pulse rate is normal or slightly elevated. If there is high fever or tachycardia they point toward a complicated acute appendicitis [48].
Patients with appendicitis lie supine, with the right thigh drawn up, because the movements increase pain. Tenderness is often maximal at Mc Burney’s point [49].
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FIG 3- DIAGRAM SHOWING McBURNEY POINT
Direct rebound tenderness is present, in addition, referred or indirect rebound tenderness is present. This referred tenderness is felt maximally in the right lower quadrant, which indicates localised persistent irritation [48]. Any movement, including coughing (Dunphy’s sign), may cause increased pain [10]. The Rovsing’s sign – pain in the right lower quadrant when palpation pressure is exerted in the left lower quadrant – implicate peritoneal irritation. Hyperaesthesia in the area supplied by spinal nerve T10, T11, T12 frequently accompanies acute appendicitis. Depending on the severity of inflammation there may be muscular resistance to palpation of the abdominal wall. Early in the disease, resistance is due to voluntary guarding and as peritoneal irritation
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progresses muscle spasm increases and becomes largely involuntary, true reflex rigidity due to contraction of muscles directly beneath the inflamed parietal peritoneum.
Classic presentation will not be there in all patients so the surgeon is constantly reminded of this in practice and patients may have none or only a few of the symptoms.
This deviation in finding is due to the variation in anatomic position of the appendix. If the appendix is retrocecal in position then the tenderness will be more marked in the flank and less striking in the anterior abdominal. In pelvic appendicitis rectal examination will reveal tenderness and palpable appendix [50]. Psoas sign – stretching the psoas by extension of the hip or further flexion against resistance can initiate a positive psoas sign, indicating irritation of the muscle by an inflamed appendix [42].
4.8. DIAGNOSIS IN SPECIAL PATIENT POPULATION
4.8.1. Acute appendicitis in infants and young children:
The diagnosis of appendicitis in infants and young children is difficult for many reasons. The patient is unable to give accurate history and also appendicitis is infrequent, acute non specific abdomen pain is common in infants and children. Because of such factors the diagnosis and treatment is often delayed and hence complications develop [51,52 ]. Two thirds of children with appendicitis have had symptoms for more than 3 days before appendectomy [52]. Vomiting, fever, irritability, flexing of thighs, diarrhoea are likely symptoms. Abdominal distension is the most common physical finding. among
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the most common atypical findings in children with appendicitis are absence of fever, absence of rovsings sign , normal or increased bowel sounds and absence of rebound pain.as in adults total leukocyte count is not a reliable test [54] .
The incidence of perforation in infants <1 yr is almost 100% and also it decreases with age, it is still 50% at 5 years of age. The mortality in this group remains as high as 5 % [52].
4.8.2. Acute appendicitis in the elderly:
Appendicitis has a much greater mortality rate among elderly persons when compared with young adults. The increased risk of mortality appears to result from both delay in seeking medical care and delay in making the diagnosis [55]. The presence of other diseases associated with aging contributes to mortality, but the major reason for the increased mortality of appendicitis in the aged is delay in treatment. Classic symptoms are present in elderly persons but are often less pronounced. Right lower quadrant pain localizes later and may be milder in elderly persons. On initial physical examination, the findings are often minimal, although right lower quadrant tenderness will eventually be present in most patients [56]. Approximately 25% of elderly patients will have a ruptured appendix at the time of operation. Although other factors play a role, delay in seeking care and in making the diagnosis are the major reasons for perforation. Routine CT scanning appears to be reducing the delay in diagnosis often associated with appendicitis
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in theelderly [56]. It is imperative, therefore, that once the diagnosis of acute appendicitis is made, an urgent operation must be advised
4.8.3. Acute appendicitis during pregnancy:
The risk of appendicitis during pregnancy is the same as it is in nonpregnant women of the same age; the incidence is 1 in 2000 pregnancies. Appendicitis occurs more frequently during the first two trimesters, and during this period the symptoms of appendicitis are similar to those seen in nonpregnant women [57]. Surgery should be performed during pregnancy when appendicitis is suspected, just as it would be in a nonpregnant woman. As in the nonpregnant patient, the effects of a laparotomy that produces no findings are minor, whereas the effects of ruptured appendicitis can be catastrophic. Recent studies indicate that there is no increase in morbidity and mortality with laparoscopic appendectomy versus open appendectomy for the patient or the fetus [58]. During the third trimester of pregnancy, the cecum and appendix are displaced laterally and are rotated by the enlarged uterus. This results in localization of pain either more cephalad or laterally in the flank, leading to delay in diagnosis and an increased incidence of perforation. Factors such as displacement of the omentum by the uterus also impair localization of the inflamed appendix and result in diffuse peritonitis. In cases of uncomplicated appendicitis, the prognosis for the infant following appendectomy is directly related to the infant’s birth weight. If peritonitis and sepsis ensue, infant mortality increases because of prematurity and the effects of sepsis. The selection of
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imaging studies for the workup of suspected appendicitis during pregnancy is often controversial. The use of ionizing radiation on a developing fetus should always be avoided. Ultrasound and magnetic resonance imaging (MRI) have been shown to be both sensitive and specific in evaluating patients; however, their lack of immediate availability in most hospitals may delay diagnosis. The effects of radiation on the fetus are significantly decreased after the first trimester [57]. Acute appendicitis can be confused with pyelitis and torsion of an ovarian cyst. However, death from appendicitis during pregnancy is mainly caused by a delay in diagnosis. In the final analysis, early appendectomy is the appropriate therapy in suspected appendicitis during all stages of pregnancy
4.9. DIFFERENTIAL DIAGNOSIS
The differential diagnosis of abdominal pain is a stimulating exercise. When the classic symptoms of appendicitis are present, the diagnosis of appendicitis is usually easily made and is seldom missed. When the diagnosis is not obvious, knowledge of the differential diagnosis becomes important. Most of the entities in the differential diagnosis of appendicitis also require operative therapy or are usually not made worse by an exploratory laparotomy. Therefore, it is essential that one eliminate those diseases that do not require operative therapy and can be made worse by operation, such as pancreatitis, myocardial infarction, and basilar pneumonia. The diseases in young children that are most frequently mistaken for acute appendicitis are gastroenteritis, mesenteric
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lymphadenitis, Meckel diverticulum, pyelitis, small intestinal intussusception, enteric duplication, and basilar pneumonia. In mesenteric lymphadenitis, an upper respiratory tract infection is often present or has recently subsided. Acute gastroenteritis is usually associated with crampy abdominal pain and watery diarrhea. Intestinal intussusception occurs most frequently in children younger than 2 years of age, an age at which appendicitis is uncommon. With intussusception, a sausage-shaped mass is frequently palpable in the right lower quadrant. The preferred diagnostic procedure is a gentle barium enema, which, in addition to making the diagnosis, usually reduces the intussusception. In teenagers and young adults, the differential diagnosis is different in men and women. In young women, the differential diagnosis includes ruptured ectopic pregnancy, mittelschmerz, endometriosis, and salpingitis [59]. Chronic constipation also needs to be considered in young women. The symptoms that accompany the acute onset of regional enteritis can mimic acute appendicitis, but a history of cramps and diarrhea and the lack of an appropriate history for appendicitis are hints that the diagnosis is regional enteritis. In young men, the potential list of differential diagnoses is smaller and includes the acute onset of regional enteritis, right-sided renal or ureteral calculus, torsion of the testes, and acute epididymitis. In older patients, the differential diagnosis of acute appendicitis includes diverticulitis, a perforated peptic ulcer, acute cholecystitis, acute pancreatitis, intestinal obstruction, perforated cecal carcinoma, mesenteric vascular occlusion, rupturing aortic aneurysm, and the disease entities already mentioned for young adults.
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4.10. INVESTIGATIONS
The diagnosis of acute appendicitis is mainly by clinical judgement which depends on the experience of the surgeon but there are some investigations which will help the surgeon in the diagnosis. These include White blood cell count, urine analysis, plain x- ray of abdomen, ultrasound scanning and computerised tomography of abdomen, aspiration cytology of peritoneal cavity and diagnostic laparoscopy.
4.10.1. White blood cell count:
Many laboratory studies are helpful in the diagnosis of acute appendicitis but no single test is definitive. Total white blood cell count is the most useful and commonly done laboratory test. In uncomplicated acute appendicitis the white cell count is slightly elevated but much higher counts are seen in complicated acute appendicitis with gangrenous changes or perforation. Total white cell count ranging from 10000 to 18000 cells per cm. is commonly seen in patients with acute uncomplicated appendicitis with polymorphonuclear predominance. The value of total white cell count varies widely, a white cell count above this level increases the possibility of complicated acute appendicitis.
4.10.2. Urine analysis:
Urine analysis is usually done to rule out urinary tract infection and the presence of white blood cells and red blood cells may be represent ureteral or bladder irritation as a result of an inflamed appendix. This is commonly seen in pelvic appendicitis.
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4.10.3. Diagnostic scores:
In an attempt to help the surgeon in diagnosis of acute appendicitis many scoring system have been developed which will increase the diagnostic accuracy and reduce the incidence of negative appendectomy [60, 61]. The most popular scoring system used is, developed by Alvarado [61] which was based on a retrospective analysis of 345 patients with abdominal pain suspicious of appendicitis. This scoring system gives points for symptoms (migration of pain, nausea and anorexia), physical signs (right lower quadrant tenderness, rebound tenderness and pyrexia) and laboratory values (leucocytosis and a left shift). Although these scoring systems can help guide clinical thinking, they do not eventually improve diagnostic accuracy [62].
4.10.4. Inflammatory markers:
Laboratory findings in acute appendicitis include a variety of markers of acute inflammation. An increased WBC count in the range of 11000 – 17000/mm3 is seen in approximately 80% patients but specificity is poor. An elevated proportion of granulocytes in the total WBC count or total neutrophil count is also elevated in vast majority of patients with appendicitis but not specific. CRP is synthesized by liver and rises within 12 hours of an inflammatory process. Although CRP is elevated in 50-90 % cases of appendicitis , it is non specific when cut off values of 5-25mg/dl is used .when clinical findings are compare with inflammatory markers, the latter are stronger predictors of appendicitis than individual history or physical findings [63].
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4.10.5. Radiological imaging:
With rare exceptions, plain roentgenologic examination of the abdomen is of little help in the differential diagnosis of acute appendicitis. The exceptions are when a fecalith is demonstrated (usually in the right lower quadrant) and when other diagnoses such as acute cholecystitis, perforating duodenal ulcer, perforating colon cancer, acute diverticulitis, and pyelonephritis are being excluded. It is not unusual to see cecal distention or a sentinel loop of distended small intestine in the right lower quadrant in patients with acute appendicitis. In late appendicitis with perforation and abscess formation, a mass can often be demonstrated that is extrinsic to the cecum. There may be scoliosis to the right, lack of the right psoas shadow, lack of small bowel gas in the right lower quadrant with abundant gas elsewhere in the small bowel, and signs of edema of the abdominal wall. With late appendicitis and generalized peritonitis, there is an ileus pattern with generalized gas throughout the small and large intestine. Barium enema (BE) examination was recommended in the past in young women in whom the diagnosis was still in question after hours of observation and in patients with a debilitating systemic disease, such as leukemia, in whom the operative risk is markedly increased [64]. The findings of significance on BE include lack of filling or partial filling of the appendix and an extrinsic pressure defect on the cecum (the “reverse 3” sign) [65].
Computed tomography (CT) and ultrasonography (US) are now preferred to BE in these circumstances. As demonstrated in many studies, an experienced radiologist is able to diagnose acute appendicitis using US with an accuracy greater than 90% [66-68].
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Appendicitis is diagnosed if the maximal cross-sectional diameter of appendix exceeds 6 mm, if it is noncompressible, if an appendolith is present, or if a complex mass is demonstrated [69]. There are other criteria that are not universally agreed on, such as rigidity and nonmobility. Nonvisualization of the appendix is not a criterion for appendicitis. US can also be helpful in the diagnosis of perforated appendicitis with abscess formation. Studies that compared US and CT have demonstrated CT to be more accurate than US in the diagnosis of appendicitis in clinically equivocal cases.3 Therefore, US should be used only when an experienced radiologist with an interest in appendicitis is available. Although more expensive, CT has also been demonstrated to be of benefit in the diagnosis of acute appendicitis and has an accuracy greater than 94%
[70, 71]. The cost can be reduced with no significant loss in diagnostic accuracy by performing a limited, unenhanced CT [72]. Appendicitis is diagnosed when the appendix is thickened with a diameter greater than 6 mm; a phlegmon, fluid, or abscess is present;
there is an appendolith; and there are inflammatory changes in the periappendiceal fat (streaking and poorly defined increased attenuation) [70, 71] The presence of pericecal inflammation without the presence of an inflamed appendix or an appendolith without the presence of periappendiceal inflammation are both insufficient to diagnose acute appendicitis. An important consideration for CT in the diagnosis of acute appendicitis is when to use it. In one study, CT scanning excluded appendicitis in almost half of the patients in the study and identified an alternative diagnosis in 51% of those patients. The routine use of CT in patients with suspected appendicitis avoids unnecessary appendectomies and unnecessary delays before surgical treatment and saves money In
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another institution, the routine use of CT scanning for the evaluation of suspected appendicitis has led to a decrease in the negative appendectomy rate from 23% to 1.7%
[54]. CT is not indicated in patients with an unequivocal diagnosis of appendicitis or in patients with a low risk of the diagnosis. In menstruating women and any patient with an equivocal diagnosis, a CT scan is probably indicated. An added benefit of the use of CT is that an identified abscess can be percutaneously drained during the same procedure [74].
FIG 4- CT image of acute appendicitis
4.10.6. Diagnostic laparoscopy:
At times instead of clinical examination and all the diagnostic tests the diagnosis of acute appendicitis is not definite. Necessary imaging studies may also prove non confirmatory, in such instances diagnostic laparoscopy can provide a direct examination of the appendix and a survey of the other intra abdominal organs for possible causes of
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pain. This technique is reserved primarily for women of child bearing age in whom pre- op pelvic ultrasound and computed tomography fails to provide a diagnosis. Concern about the possible adverse effects of a missed perforation and peritonitis in future fertility prompts earlier intervention in this patient population.
4.11 MANAGEMENT
4.11.1. Non operative management:
Appendectomy was one of the first intra abdominal operations performed and appendicitis has long been a surgically treated disease. Based on the high rate of failure with antibiotics alone, non operative management of acute appendicitis cannot be recommended. Antibiotic treatment may be a useful temporary measure, however in environments with no surgical capabilities such as in space flight and submarine travel [75].
4.11.2. Surgical removal of appendix:
Most patients with acute appendicitis are managed by prompt surgical removal of the appendix either laparoscopically or by open appendectomy. Several prospective randomised studies have compared laparoscopic and open appendectomy and the overall differences in outcome remains small. The percentage of appendectomies performed laparoscopically continues to increase [76]. Obese patients have less pain and shorter hospital stay after laparoscopic versus open appendectomy [77]. Patients with perforated appendix have lower rates of wound infection following laparoscopic removal of the
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appendix [78]. Patients treated laparoscopically have improved quality of life scores 2 weeks after surgery and lower readmission rates. As compared with open appendectomy the laparoscopic approach involves higher operating room costs. For patients in whom the diagnosis remains uncertain after the preoperative evaluation diagnostic laparoscopy is useful because it allows the surgeon to examine the remainder of the abdomen including the pelvis for abnormalities.
4.11.3. Preoperative preparation:
It is not necessary to rush a patient with a presumed diagnosis of acute appendicitis directly to the operating room. Retrospective reviews of operative delays of more than 12 hours do not negatively affect patient outcomes [79]. All patients, especially those with a presumed diagnosis of peritonitis, should be adequately prepared before being taken to the operating room. Selected patients with a palpable right lower quadrant mass, periappendiceal phlegmon, or abscess on imaging may be managed without operation [80]. Intravenous fluid replacement should be initiated and the patient resuscitated as rapidly as possible, especially when peritonitis is suspected. Once the patient has a good urinary output, it can be assumed that resuscitation is complete.
Nasogastric suction is especially helpful in patients with peritonitis and profound ileus. If the patient’s body temperature is higher than 39° C, appropriate measures should be taken to reduce fever before beginning an operation. A broad-spectrum antibiotic should be administered preoperatively to help control sepsis and to reduce the incidence of
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postoperative wound infections. If, at the time of operation, the patient has early appendicitis, antibiotic administration should be stopped after one postoperative dose.
Antibiotics should be continued as clinically indicated in patients who have gangrenous or ruptured appendicitis with localized or generalized peritonitis.
4.11.4. Examination under anesthesia
After the induction of anesthesia, the patient’s abdomen should be systematically palpated. Such an examination may, on occasion, demonstrate another pathologic condition to be the cause of the patient’s symptoms, such as acute cholecystitis. It also may be possible to palpate an appendiceal mass that will confirm the suspected diagnosis.
4.11.5. Uncomplicated Appendicitis Without a Palpable Mass
In this circumstance, when the diagnosis of acute appendicitis has been made and there is no reason to suspect that the appendix has ruptured, an appendectomy should be performed. One recommended incision for a routine appendectomy is a transverse one (i.e., Rockey- Davis, Fowler–Weir Mitchell incisions). The incision is made in a transverse direction, 1 to 3 cm below the umbilicus, and is centered on the midclavicular line. The length of the incision should be approximately 1 cm longer than the breadth of the surgeon’s hand. The aponeurosis and muscles of the abdominal wall are split or incised in the direction of their fibers.
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Exposure of the appendix through this incision is better when compared with that obtained through the classic McBurney incision, particularly in patients with a retrocecal appendix and in those who are obese. The other recommended incision, the gridiron, or muscle-splitting one (McBurney incision), can be used. This is the most widely used incision in uncomplicated appendicitis. The skin incision is made through a point one- third of the way along a line from the anterosuperior spine of the ileum to the umbilicus.
The incision is made obliquely, beginning inferiorly and medially, and extending laterally and superiorly. It should be 8 to 10 cm in length, with its most medial extent being the lateral edge of the rectus muscle. The aponeurosis and muscles of the abdominal wall are split or incised in the direction of their fibers in such a manner that the entire skin incision can be used for exposure. After entering the peritoneum, the appendix is found as described for the transverse incision. The exposure through a McBurney incision, especially for a retrocecal appendix, can be awkward unless the appendix lies immediately below the incision. If necessary, the incision can be extended medially, partially transecting the rectus sheath, but this maneuver is usually helpful only in a pelvic appendicitis. If there is doubt about the diagnosis of acute appendicitis and an exploratory laparotomy is indicated, a vertical midline incision is more appropriate. An appendectomy can be performed with little difficulty through such an incision. After the peritoneum is opened, the appendix is identified by following the anterior cecal taenia to the base of the appendix. The inflamed appendix is coaxed into the wound by gentle traction and the transection of adhesions, if present. If the appendix is retrocecal or retroperitoneal, or if the local inflammation and edema are intense, exposure is improved
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by dividing the lateral peritoneal reflection of the cecum. At the end of this maneuver, the cecum should lie within the wound and the appendix should be at the level of the anterior abdominal wall so that continuing vigorous retraction is unnecessary while removing the appendix .
If the appendix is not adherent, its base can be identified easily because the entire appendix often pops into the operative field. If the appendix is adherent, however, its base may be difficult to recognize. Aids in recognition include the following:
1. All three taeniae lead to and end at the base of the appendix.
2. The ileocecal junction can usually be identified, just below which is the base of the appendix.
If the appendix does not come into the wound but the base has been identified, an Allis clamp can be placed around but not on the appendix for traction. An effort is made to deliver the tip of the appendix into the operative field. If the appendix is not adherent to surrounding tissues, traction on the Allis clamp is usually successful in delivering the appendix. Once the appendix has been freed up, the mesoappendix is transected beginning at its free border, taking small bites of the mesoappendix between pairs of hemostats placed approximately 1 cm from and parallel to the appendix. This process should be repeated until the base of the appendix is reached. If exposure of a long, adherent appendix is difficult, the mesoappendix can be transected in a retrograde manner beginning at the base of the appendix. There are three ways to handle the appendiceal stump: simple ligation, inversion, and a combination of ligation and inversion. Either simple ligation or inversion is acceptable and has a comparable incidence of
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complications. The combination of ligation and inversion is not recommended, because it does not reduce the risk of septic complications, but it does create conditions conducive to the development of an intramural abscess or mucocele. Also, the ligated and inverted appendiceal stump may later appear on a subsequent BE as a cecal “tumor” and be a source of diagnostic difficulties [30].
Simple ligature of the appendiceal stump is accomplished by crushing the appendix at its base with a hemostat, then moving the hemostat and replacing it on the appendix just distal to the crushed line. A ligature of monofilament suture is placed in the groove caused by the crushing clamp and is tied tightly. The appendix is transected just proximal to the hemostat and removed. Inversion of an unligated stump using a Z-stitch rather than the more conventional purse string suture, is preferred. The upper level of the Z-stitch is placed as a Lembert suture in the cecum, just distal to the base of the appendix.
The suture is then brought around the base of the appendix and continued as a second Lembert suture beneath the base of the appendix. The appendix is then transected between clamps, the stump is inverted into the cecum, the proximal clamp is removed, and the ends of the Z-stitch are tied over the stump of the appendix. The appendiceal stump is not ligated. If the appendiceal stump is unsuitable for inversion because of edema, it should simply be ligated and not inverted.
4.11.6. Laparoscopic appendectomy
Laparoscopic and minimal access surgery continues to expand in the field of general surgery, and diagnostic laparoscopy and laparoscopic appendectomy have
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become accepted procedures in many surgeons’ practices. The early use of diagnostic laparoscopy in patients with right lower quadrant abdominal pain and suspected appendicitis reduces the risk of appendiceal perforation and the negative appendectomy rate to less than 10% [82]. Diagnostic laparoscopy is particularly useful in women of reproductive age and in the obese. In the former, frequently confounding gynecologic disorders can be well visualized to provide the diagnosis, and in the latter, laparoscopy can eliminate the morbidity risks of a large incision. Performing an appendectomy with a normal-appearing appendix has a relatively low risk and will remove appendicitis from the differential diagnosis of right lower quadrant pain in the future. However studies have shown that it is safe to not proceed with appendectomy if the appendix
appears normal [83, 84].
Conversion of diagnostic laparoscopy to therapeutic laparoscopy is easily accomplished by the addition of other ports. Trocar placement for laparoscopic appendectomy is a matter of surgeon choice with consideration of the triangle rule for port placement. Diagnostic laparoscopy is usually performed through a periumbilical port, with a 10/11-mm port added midway between the umbilicus and pubis and a 5-mm port placed over the appendix or the right midlateral abdomen if appendectomy is performed. Once the diagnosis is confirmed, the mesoappendix can be taken down with either hemoclips or the Harmonic Scalpel. The appendix is amputated from the cecum between endoloops or with an endo-Gastro intestinal anastomic stapler. The appendix can then be removed from the abdomen with a specimen pouch or withdrawn into the 10/11- mm port. Care should be taken to prevent contact of the appendix or its contents with the
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wound edges. There is general agreement that patients undergoing laparoscopic appendectomy have less postoperative pain, a lower rate of wound infection, a lower overall complication rate, a more rapid return to diet, a shorter hospital stay, a longer operative time, and more equipment charges in the operating room [85-88]. In contrast, a more rapid return to work and a lower complication rate are more controversial claims because prospective studies show differing results [89, 90]. Laparoscopic appendectomy results in a lower wound infection rate comparable with an open procedure but has a higher intra-abdominal abscess rate if the appendix is perforated [91]. Relative contraindications to laparoscopic appendectomy include previous abdominal surgery precluding safe trocar placement, uncontrolled coagulopathy, and significant portal hypertension.
Laparoscopic appendectomy appears to be safe and efficacious. It provides a rapid diagnosis and a significant reduction in negative appendectomy rates in females of childbearing age with suspected appendicitis. Minimal access surgery reduces the morbidity risk in obese patients who require an appendectomy
4.11.7. Perforated or Gangrenous Appendicitis With a Periappendiceal Mass
When a mass is detected by examination under anesthesia, a transverse incision is made over the most prominent portion of the mass. The muscles and aponeuroses are split along their lines of cleavage in gridiron fashion. After entering the peritoneal cavity, the wound should be packed immediately to prevent contamination of the abdominal cavity. As mentioned earlier, the mass may be made up of omentum and loops of small
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intestine adherent to the inflamed appendix, and an abscess may not be present. If feasible, an appendectomy is then performed; usually it will not be possible to invert the stump, so simple ligation is preferred. It is not necessary to place a subfascial drain in a patient with a gangrenous appendix and minimal or no periappendiceal pus. If there is a periappendiceal abscess and the tissues are fixed so as to create a dead space, the cavity should be drained with one or more closed-suction drains brought out through a separate stab incision. Before fascial closure, the right iliac fossa and the wound should be liberally irrigated. Muscles and aponeuroses should be closed with interrupted nonabsorbable sutures. The skin should be left open, to be closed with adhesive paper tapes on the fifth or sixth postoperative day. Parenteral antibiotics should be continued for 5 days after operation or until clinical signs indicate no infection.
4.11.8.Perforated Appendicitis With Localized Abscess Formation
If, at the time of initial physical examination, a well localized periappendiceal mass is found and the patient’s symptoms are improving, it is acceptable in healthy adults to initiate parenteral antibiotic treatment and to follow the patient expectantly [92]. This form of therapy is not appropriate in children, pregnant women, or elderly patients. In these groups, an emergency operation is indicated. In two-thirds of patients, expectant treatment of an appendiceal mass succeeds, and an interval appendectomy can be performed at a later date or can be avoided altogether [91, 92]. In one-third of patients, symptoms do not subside and an emergency CT scan should be performed. If an abscess is identified on CT scan, an attempt should be made to drain the abscess percutaneously
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under CT or US guidance [74]. If not successful, the abscess should be drained surgically. The skin incision for drainage of a periappendiceal abscess is made just medial to the crest of the ilium at the level of the abscess. Using a muscle-splitting technique, the lateral edge of the peritoneum is exposed and pushed medially so that the abscess is approached from its lateral aspect. Once the abscess is entered, a finger should be used to break up the loculations. If the appendix can be freed up without breaking down adhesions, an appendectomy should be performed. If an appendectomy is not performed, an interval appendectomy can be done 3 to 6 months after drainage from the abscess has ceased and the wound has completely healed. After the wound has been thoroughly irrigated with normal saline, a closed-suction drain should be inserted into the abscess cavity and brought out through a separate stab wound in the flank. The muscles and aponeuroses are closed with interrupted nonabsorbable sutures, and the skin and subcutaneous tissues are packed open with saline-soaked gauze. The drain should be left in place until it is draining less than 50 mL/day and then advanced progressively until removed. Systemic antibiotics should be continued for 5 days postoperatively or until signs of sepsis have cleared. A daily rectal examination should be done to detect pelvic abscess. The patient may be discharged from the hospital when there is no fever 48 hours after the discontinuation of antibiotic therapy.
4.11.9. Perforated Appendicitis With Diffuse Peritonitis
The major cause of mortality from appendicitis is generalized peritonitis.
Therefore, immediate exploration is indicated in a patient with a diagnosis of acute
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appendicitis in whom the physical findings are consistent with diffuse peritonitis. If a perforated appendix and diffuse peritonitis are documented at operation, an appendectomy should be performed and the abdomen thoroughly irrigated. The use of drains in diffuse peritonitis is not recommended unless there are localized abscesses requiring drainage [93]. The wound and postoperative care should be handled as described in a patient with a periappendiceal abscess.
4.11.10. Natural Orifice Transluminal Endoscopic Surgery (NOTES):
NOTES is a surgical procedure using flexible endoscopes. In this procedure access is gained via organs that are reached through a natural external orifice. The advantages include the reduction of post operative wound pain, shorter convalescence, avoidance of wound infection and abdominal wall hernia and the absence of scars.
4.11.11. Post operative care:
Patients with non perforated appendix require 24-48 hours hospital stay. Post operative care for both the laparoscopic and open approach is similar. Patients can be started on a clear liquid immediately and then diet can be advanced as tolerated. No post operative dose of antibiotics is required. Patients can be discharged when they tolerate a regular diet and oral analgesics.
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4.11.12. Perforated appendicitis:
When appendicitis progresses to perforation improvement depends on the nature of the perforation. If the perforation is contained a solid or semi solid periappendiceal mass of inflammatory tissue can form referred to as a phlegmon. In such instances appendectomy can be difficult due to dense adhesions and inflammation. Ileocecectomy may be necessary if the inflammation extends to the wall of the cecum. Complications such as inadvertent enterotomy, post operative abscess or enterocutaneous fistula may ensure. Because of these potential complications many support an initially non operative approach [94, 95, 96]. Such an approach is only advisable if the patient is not ill appearing. Non operative management include intra venous antibiotics and fluids as well as bowel rest. Patients should be closely monitored in the hospital during this time.
Treatment failure as evidenced by bowel obstruction, sepsis, or persistent pain fever or leucocytosis requires immediate appendectomy. If fever, tenderness and leucocytosis improve diet can be slowly advanced usually within 3-5 days.
In some cases continued perforation may result in a pus filled abscess cavity. If imaging studies demonstrate an abscess cavity, CT or ultra sound guided drainage can often be performed per cutaneously or transrectally [97, 98]. Following drainage the patient is closely monitored in the hospital and is placed on bowel rest with intra venous antibiotics and fluids.
Finally full perforation can occur causing intra peritoneal dissemination of pus and fecal material. The patient is typically quiet ill and perhaps septic. Urgent laparotomy is
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necessary for appendectomy and irrigation and drainage of the peritoneal cavity. If the diagnosis of perforated appendix is known the appendectomy can be performed through a right lower quadrant incision. Sometime patients with free perforation present with acute abdomen and generalised peritonitis and he decision to perform laparotomy is made without a definite diagnosis. In such instances a midline incision is prudent and appendectomy is done. Peritoneal drains are not necessary, as they do not reduce the incidence of wound infection or abscess formation after appendectomy for perforated appendicitis [99]. The operative decision is whether or not to close the incision. Because of wound infection rates ranging from 30-50% with primary closure of grossly contaminated wounds many advocate delayed primary or secondary closure [100].
4.11.13. Interval appendectomy:
Treatment following initial non operative management of an appendiceal phlegmon or abscess is controversial. Some recommend interval appendectomy [101,102] – appendectomy performed approximately 6 weeks after the inflammation has subsided while others consider subsequent appendectomy unnecessary [103,104].
Because it can be now performed laparoscopically as an outpatient basis with low morbidity, interval appendectomy should be considered for most patients who were initially treated with non operative management [105].
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4.11.14. Incidental Appendectomy:
Because of the difficulty in diagnosing appendicitis, it is not uncommon for a normal appendix to be found at appendectomy. Sometimes referred to as misdiagnosis this can occur more than 15% of the time with considerable higher percentage in infants, in elderly and in young women [106]. Negative appendectomy is to be avoided when possible, due to the risk of surgical complications and the cost associated with unnecessary surgery [107].
Nonetheless in certain instances the diagnosis is in doubt and a non inflamed appendix is found at laparotomy or laparoscopy, the surgeon must then decide whether or not to remove the appendix. For multiple reasons it is advisable to remove the grossly normal appendix. If the pain recurs and the appendix has been removed appendicitis will no longer be a possibility and can be removed from differential diagnosis.
There is strong evidence that a surgeon’s gross assessment of the appendix can be inaccurate. In one study 11 (26%) out of 43 appendectomy specimens described the removal by the surgeon showed acute appendicitis on pathological examination [108]. As a result removal of a grossly normal appendix at the time of appendectomy is recommended. When a normal appendix is discovered at appendectomy it is important to look for the other possible causes of the patient’s symptoms.
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4.11.15. Chronic appendicitis:
Although rare, chronic appendicitis can explain persistent abdominal pain in some patients. Patients do not present with the typical symptoms of acute appendicitis they complaint of weeks or years of right lower quadrant pain. They may describe an initial episode with more classic symptoms of acute appendicitis, for which no treatment was delivered [109]. Diagnosis can be difficult as laboratory and radiological studies are typically normal. Pathology evaluation revealing chronic inflammation confuses the diagnosis. Because the diagnosis is often uncertain pre operatively laparoscopy can be a useful tool to allow exploration of the abdomen [110].
4.12. PROGNOSIS AND COMPLICATIONS
Postoperative complications occur in 5% of patients with an unperforated appendix but in more than 30% of patients with a gangrenous or perforated appendix.
The most frequent complications after appendectomy are wound infection, intraabdominal abscess, fecal fistula, pylephlebitis, and intestinal obstruction.
Subcutaneous tissue infection is the most common complication after appendectomy. The organisms most frequently cultured are anaerobic Bacteroides species and the aerobes Klebsiella, Enterobacter, and Escherichia coli [111]. When early signs of wound infection (undue pain and edema) are present, the skin and subcutaneous tissue should be opened. The wound should be packed with saline-soaked gauze and reclosed with Steri-
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Strips in 4 to 5 days. Pelvic, subphrenic, or other intraabdominal abscesses occur in up to 20% of patients with a gangrenous or perforated appendicitis. They are accompanied by recurrent fever, malaise, and anorexia of insidious onset. CT scanning is of great help in making the diagnosis of intraabdominal abscess. When an abscess is diagnosed, it should be drained either operatively or percutaneously. Some fecal fistulas close spontaneously, provided that there is no anatomic reason for the fistula remaining open. Those that do not close spontaneously obviously require operation. Pylephlebitis, or portal pyemia, is characterized by jaundice, chills, and high fever. It is a serious illness that frequently leads to multiple liver abscesses. The infecting organism is usually E. coli. This complication has become rare with the routine use of antibiotics in complicated appendicitis. Although not frequent, true mechanical bowel obstruction may occur as a complication of acute appendicitis. As with any other mechanical small bowel obstruction, operative therapy is indicated.
4.12.1. Chronic and recurrent appendicitis
There are occasional patients who have had one or more attacks of what appears to be acute appendicitis. Between attacks, these patients are free of symptoms and the physical examination is normal. In such patients, if a fecalith is present on abdominal radiograph, if a BE demonstrates no filling of the appendix, or if repeated examinations during an attack provide evidence of recurrent appendicitis, elective appendectomy should be undertaken [112]. To sustain a diagnosis of chronic appendicitis, the resected appendix must demonstrate fibrosis in the appendiceal wall, partial to complete obstruction of the
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lumen, evidence of old mucosal ulceration and scarring, and infiltration of the wall of the appendix with chronic inflammatory cells.
FIG 5- UNCOMPLICATED ACUTE APPENDICITIS
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FIG 6- UNCOMPLICATED ACUTE APPENDICITIS
FIG 7-LAPAROSCOPIC APPENDICECTOMY
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FIG 8- COMPLICATED ACUTE APPENDICITIS
