Home Translating Report News Physicians Diseases Body Sites Lab tests Search
Home Diseases and Health Information

Background

An acute appendicitis is often the first thought to the layperson when a sharp onset of pain in the right lower abdominal quadrant occurs. This relatively common disease is usually diagnosed by the surgeon. However, the pathologist plays an important role not only in confirming the diagnosis but in ruling out other conditions which may mimic the disease.

OUTLINE

Epidemiology  
Disease Associations  
Pathogenesis  
Laboratory/Radiologic/
Other Diagnostic Testing
 
Gross Appearance and Clinical Variants  
Histopathological Features and Variants  
Special Stains/
Immunohistochemistry/
Electron Microscopy
 
Differential Diagnosis  
Prognosis  
Treatment  
Commonly Used Terms  
Internet Links  

EPIDEMIOLOGY CHARACTERIZATION
SYNONYMS  
INCIDENCE  


Acute appendicitis in late adulthood: incidence, presentation, and outcome. Results of a prospective multicenter acute abdominal pain study and a review of the literature.

Kraemer M, Franke C, Ohmann C, Yang Q; Acute Abdominal Pain Study Group.

Department of Colorectal Surgery, Singapore General Hospital, Singapore.


Langenbecks Arch Surg 2000 Nov;385(7):470-81 Abstract quote

BACKGROUND: Acute appendicitis is the second most common cause of surgical abdominal disease in late adulthood. It is a serious condition: major errors in management are made frequently and the condition is associated with significant morbidity and mortality. Data collected within a multicenter prospective trial and a literature review were used to analyze diagnostic and therapeutic difficulties in detail.

METHODS: In a multicenter intervention study (MEDWIS A 70) data from 2,280 patients with acute abdominal pain were collected prospectively. Patients with histologically proven acute appendicitis, aged 50 years and older (n=102), were compared with younger patients (n=417) to determine differences in presentation, clinical course, and outcome. The basis for the literature review was a Medline search for appendicitis in late adulthood and in the elderly, covering the years 1980-1998. In addition, studies on clinical presentation of acute appendicitis in all age groups were also reviewed and appropriate data were extracted.

RESULTS: Patients aged 50 years and older with acute abdominal pain had a significantly higher incidence of surgery. Fourteen percent had acute appendicitis (27% in younger patients), with an increased complication rate (20% vs. 8%) and mortality (3% vs. 0.2%). Significantly more signs and symptoms suggestive of acute abdominal disease and peritonitis were recorded among older patients, reflecting the higher perforation rate (35% vs. 13%). Clinical presentation of appendicitis in younger patients was far more ambiguous. There were no significant differences in outcome between older and younger patients as regards perforations. Perforations are directly associated with treatment delay. Overall delay is a result of late presentation of older patients to hospital and postadmission delay.

CONCLUSIONS: Appendicitis in late adulthood is characterized by a delay in treatment, high perforation rates, and unfavorable outcome parameters, all mutually correlating. Older patients with acute abdominal pain are high-risk patients, unlike their younger counterparts. They have to be clinically evaluated by experienced surgeons within a narrow time margin. The problem of late presentation and/or referral should be addressed, perhaps by education of primary care physicians and the public.


Appendicitis: why so complicated? Analysis of 5755 consecutive appendectomies.

Pittman-Waller VA, Myers JG, Stewart RM, Dent DL, Page CP, Gray GA, Pruitt BA Jr, Root HD.

Department of General Surgery at the University of Texas Health Science Center at San Antonio, 78229-3900, USA.

 

Am Surg 2000 Jun;66(6):548-54 Abstract quote

A perceived high rate of complicated (gangrenous or perforated) appendicitis, despite advances in laboratory and radiographic diagnostic modalities, prompted a review of our experience with appendicitis followed by a prospective analysis that examined the time course from presentation to definitive treatment in 218 consecutive patients.

In 5755 appendectomies, our overall rate of complicated appendicitis was 32 per cent; higher in males, in the young, and in the elderly; and relatively stable over each year reviewed. Prospectively, we determined that of the various time intervals, the time from the onset of symptoms to first seeking medical attention is the only significant predictor of complicated appendicitis (39.8 vs 16.5 hours for acute appendicitis). On the other hand, the time from surgical evaluation to operative intervention was significantly shorter for complicated appendicitis (3.8 vs 4.7 hours for acute appendicitis).

The high rate of complicated appendicitis with its subsequent sequelae of increased morbidity and resource expenditure is primarily the direct result of patient delay in seeking medical attention and not the result of diagnostic dilemma or surgical delay. Public education, specifically targeting those groups at risk, may provide a substantial and significant solution to the complicated appendix.

 

DISEASE ASSOCIATIONS CHARACTERIZATION
PREGNANCY  


Acute appendicitis in pregnancy. A review of 52 cases.

Al-Mulhim AA.

Department of Obstetrics and Gynecology, King Fahd Hospital of the University, Al-Khobar, Saudi Arabia.

Int Surg 1996 Jul-Sep;81(3):295-7 Abstract quote

Acute appendicitis in pregnancy is the most common non-obstetric complication warranting emergency laparotomy.

A retrospective study of 52 pregnant patients who underwent laparotomy for suspected acute appendicitis between June 1982 and June 1995 revealed a histopathological diagnosis in 29 (56%) patients. The hospital incidence for acute appendicitis in pregnancy was 0.09% (1 in 1102 deliveries). There were 10 (19%) patients who presented in the first trimester, 31 (60%) second trimester, 8 (15%) third trimester and 3 (6%) patients in the puerperium.

Abdominal pain in the right lower quadrant was the most common presenting symptom. Abdominal tenderness and rebound tenderness were the most common physical signs, although the latter was less marked in late pregnancy. Preoperative laboratory investigations were equivocal in reaching a decision for surgical intervention. Laparotomy was performed within 24 hours of onset of symptoms in 67% of patients. Perforation of the appendix was found in 4 (14%) patients, all of whom had symptoms exceeding 24 hours.

Wound infection occurred in 4 (9.6%) patients, 3 of whom had a perforated appendix. There were 2 (9%) fetal losses among the patients with negative laparotomies. Five (17%) other fetuses were lost in the group with diseased appendix, three of these were in patients with perforated appendix. There was no maternal death in the study.

ULCERATIVE COLITIS  


Role of appendicitis and appendectomy in the pathogenesis of ulcerative colitis: a critical review.

Koutroubakis IE, Vlachonikolis IG, Kouroumalis EA.

Department of Gastroenterology, University Hospital of Heraklion, Crete, Greece.

Inflamm Bowel Dis 2002 Jul;8(4):277-86 Abstract quote

Besides a genetic predisposition, a causal role of various environmental factors has been considered in the etiology of ulcerative colitis (UC).

The association between appendectomy and UC has recently been the subject of intense scrutiny in the hope that it may lead to the identification of important pathogenetic mechanisms. Published data from animal models of colitis demonstrated reduction in experimental colitis after appendectomy, especially if performed at an early age. Several epidemiological case control and cohort studies have shown a strong and consistent relationship. The metaanalysis of 17 case-controlled studies showed an overall odds ratio 0.312 (95% confidence intervals = 0.261-0.373) in favor of appendectomy (p < 0.0001). One of the two recent large cohort studies is in agreement with these results, but the other failed to confirm them.

All these studies have suggested that alterations in mucosal immune responses leading to appendicitis or resulting from appendectomy may negatively affect the pathogenetic mechanisms of UC. Further investigation of the role of appendectomy in UC is expected to open new fields for basic scientific research and may lead to the improvement of our understanding for the disease pathogenesis.

 

PATHOGENESIS CHARACTERIZATION
CYTOKINES  

 

Is a histologically normal appendix following emergency appendicectomy alway normal?

Wang Y, Reen DJ, Puri P.

Children's Research Centre, Our Lady's Hospital for Sick Children, Dublin, Ireland

Lancet 1996 Apr 20;347(9008):1076-9 Abstract quote

BACKGROUND: Appendixes removed from patients with suspected appendicitis often appear normal on histological examination. We examined appendix specimens for expression of abnormal amounts of cytokines, an indicator of an inflammatory response.

METHODS: Tumour necrosis factor alpha (TNFalpha) and interleukin-2 (IL-2) expression was measured by in-situ hybridisation in ten specimens from patients with acute appendicitis, 12 normal appendix specimens removed from patients undergoing elective abdominal surgery, and 31 appendix specimens from patients with a clinical diagnosis of appendicitis but an appendix histologically classified as normal. Cytokine-specific RNA antisense probes were prepared by in-vitro transcription and digoxigenin (DIG) labelled. In-situ hybridisation was done on 5 micrometer paraffin sections. Tissue sections hybridised by sense probes acted as negative control for each cytokine. Following hybridisation, the probes were detected by alkaline phosphatase labelled anti-DIG monoclonal antibody and visualised by nitroblue tetrazolium staining.

FINDINGS: All histologically proven acute appendicitis specimens demonstrated intense cellular TNFalpha mRNA expression in germinal centres and moderate levels of expression throughout the mucosa. IL-2 mRNA was strongly expressed in the lamina propria and only moderately expressed in germinal centres. Normal appendixes all showed almost complete absence of TNFalpha and IL-2 mRNA expression. Seven of the 31 histologically classified normal appendix specimens from patients with a clinical diagnosis of appendicitis demonstrated TNFalpha and IL-2 mRNA expression similar to acute appendicitis specimens in germinal centres, submucosa, and lamina propria layers.

INTERPRETATION: TNFalpha and IL-2 mRNA expression is a sensitive marker of inflammation in appendicitis. A substantial proportion of histologically normal appendixes showed clear evidence of an inflammatory response in the form of increased cytokine expression.

EOSINOPHILS  


Eosinophils in acute appendicitis: possible significance.

Aravindan KP.

Department of Pathology, Medical College, Calicut.


Indian J Pathol Microbiol 1997 Oct;40(4):491-8 Abstract quote

120 consecutive appendicectomies and 20 appendices from medicolegal autopsies were studied. The cases were grouped as. A: Acute appendicitis. B: Acute presentation, not diagnostic of acute appendicitis C: Elective appendicectomies D: Normal appendices from autopsies. Eosinophils and mast cells were counted in the muscularis, in Giemsa stained sections. The mean eosinophil and mast cell counts per mm2 were--A. 215.9; 26.5. B. 66.0; 32.1. C. 6.7; 25.8. D. 4.2; 19.6 respectively.

Eosinophil count is significantly higher in A compared to others (p < 0.0001) and there was no range overlap with C and D. B is a heterogenous group with 37.5% having eosinophil counts in the range seen in A. Cases with mural eosinophil showed histological evidence of mast cell degranulation. Eosinophil infiltration of the muscularis is an early event universally seen in acute appendicitis.

It is possible that the disease is triggered by Type I Hypersensitivity, and that infection is a later consequence.

INNERVATION  


Nitrergic hyperinnervation in appendicitis and in appendices histologically classified as normal.

Nemeth L, Rolle U, Reen DJ, Puri P.

Children's Research Centre, Our Lady's Hospital for Sick Children, University College, Dublin, Ireland.

 

Arch Pathol Lab Med 2003 May;127(5):573-8 Abstract quote

CONTEXT: The pathogenesis of appendicitis remains poorly understood. Despite new diagnostic techniques, appendices removed from patients with suspected appendicitis often appear histologically normal on conventional examination. There is increasing evidence of involvement of the enteric nervous system in immune regulation and in inflammatory responses in the gastrointestinal system.

OBJECTIVE: To investigate the nitrergic innervation of (a) acutely inflamed appendices, (b) appendices classified as histologically normal from patients with a clinical diagnosis of appendicitis, and (c) normal control appendix specimens, using the whole-mount preparation technique.

PATIENTS AND DESIGN: Full-thickness specimens were collected from 28 acutely inflamed appendices (age range, 3.2-13.4 years), 31 histologically normal appendices removed from patients (age range, 5.7-13.6 years) with suspected appendicitis, and 23 histologically normal appendices from patients (age range, newborn to 12.1 years) undergoing elective abdominal surgery (controls). Whole-mount preparation using nicotinamide adenine dinucleotide phosphate (NADPH) diaphorase histochemistry and neuronal nitric oxide synthase immunohistochemistry were performed. The density of myenteric plexus was measured with a computerized analysis system.

RESULTS: The density of myenteric plexus in normal appendix specimens was similar to that of large bowel from the newborn period up to 3 years of age; this density decreased significantly thereafter. The myenteric plexus of normal appendix specimens from patients older than 4 years demonstrated smaller ganglia connected by thin nerve bundles, compared to larger ganglia and nerve bundles in large bowel. Significant neuronal hypertrophy was found in 55% of acutely inflamed and 41% of histologically classified normal appendix specimens. The myenteric plexus of these appendix specimens had even thicker nerve bundles connecting an increased number of ganglion cells.

CONCLUSIONS: Differences in the architecture of the myenteric plexus in patients older than 3 years suggest an altered function and motility of appendix in the early years of life. The significant increase in neuronal components of the myenteric plexus in a high proportion of acutely inflamed and histologically normal appendix specimens is unlikely to have developed during a single acute inflammatory episode. This suggests an underlying chronic abnormality as a secondary response to chronic luminal obstruction or repeated inflammatory episodes in the histologically normal appendix.

 

LABORATORY/
RADIOLOGIC/
OTHER TESTS

CHARACTERIZATION
RADIOLOGIC  
CT SCAN  


The role of selective computed tomography in the diagnosis and management of suspected acute appendicitis.

Hershko DD, Sroka G, Bahouth H, Ghersin E, Mahajna A, Krausz MM.

Department of Surgery A, Rambam Medical Center, Haifa, Israel.

 

Am Surg 2002 Nov;68(11):1003-7 Abstract quote

The negative appendectomy rate in patients with clinically diagnosed acute appendicitis is 20 to 40 per cent. Recently CT has emerged as a powerful diagnostic tool in the evaluation of suspected appendicitis and its routine use has been advocated.

The objective of this study was to evaluate the impact of selective use of abdominal CT on the negative appendectomy rate. Three hundred eight patients were enrolled in this prospective study. Abdominal CT was performed in patients with uncertain clinical signs of appendicitis. CT was not performed in patients with either a very high or a very low index of suspicion. The results were compared with a retrospective analysis of 85 consecutive patients operated by clinical diagnosis alone.

One hundred twenty-seven patients had a final diagnosis of acute appendicitis. CT was performed in 198 patients (64%). The sensitivity, specificity, and accuracy of CT scans were 91, 92, and 91 per cent, respectively. Surgical management plans were altered in 54 patients after obtaining the CT results; unnecessary delay in surgical treatment or unnecessary operations were prevented in 28 and 26 patients, respectively. In addition CT detected unrelated pathologies in 23 patients.

CT was not performed in patients with low index of suspicion and none were found to suffer from acute appendicitis. The negative appendectomy rate was 17 per cent (7% men and 24% women) in patients selected for surgery on the basis of very high clinical suspicion alone. Overall the negative appendectomy rate with the selective use of CT was 16 per cent, which is significantly lower than the rate achieved by diagnosing patients on clinical grounds alone (24%).

CT is highly accurate in diagnosing or ruling out acute appendicitis and may substantially decrease the negative appendectomy rate as well as unnecessary delayed observation. We believe that CT should be performed routinely in women with suspected appendicitis and selectively in men.


Impact of abdominal CT imaging on the management of appendicitis: an update.

Fuchs JR, Schlamberg JS, Shortsleeve MJ, Schuler JG.

Department of Surgery, Mount Auburn Hospital, Cambridge, MA 02115, USA.

J Surg Res 2002 Jul;106(1):131-6 Abstract quote

BACKGROUND: Abdominal computed tomographic scanning (ACTS) has recently been shown to be an accurate diagnostic tool for appendicitis and may improve the negative exploration rate in our patient population.

MATERIALS AND METHODS: We reviewed 224 patients evaluated for appendicitis during 1998. Forty-two patients underwent appendectomy on clinical grounds alone (Group I), 182 patients underwent ACTS (Group II), and 79 patients in Group II were explored for appendicitis. Diagnostic errors, alternative diagnoses, and perforation rates were noted.

RESULTS: There were five negative explorations in Group I (11.9%) and five in Group II (6.3%), resulting in a combined negative rate of 8.3%. The negative exploration rate in women was 23.5% in Group I and 5.3% in Group II (P = 0.07), producing a combined negative rate of 10.9%. Fifty-eight alternative diagnoses were made by ACTS. The ACTS made a critical difference in the management of 67% of patients over 50 years of age and in 79% of Group II patients.

CONCLUSIONS: The negative exploration rate for appendicitis at our institution fell from 13.6 to 8.3% with selective use of ACTS. The most striking benefit occurred in women and in patients over 50 years of age.

ULTRASOUND  


Sonographic detection of normal and abnormal appendix.

Simonovsky V.

Clinic of Imaging Methods, Faculty Hospital Motol, Praha, Czech Republic.

Clin Radiol 1999 Aug;54(8):533-9 Abstract quote

AIM: The aim of the study was to assess the value of sonography in detecting the normal appendix and in identifying abnormality.

METHODS: The appendiceal wall thickness (normal: <3 mm) and ultraluminal contents (abnormal: large appendicolith, non-expressible fluid) were used as the primary criteria to determine the appendiceal status in 716 appendices. In patients who underwent appendicectomy (n = 166), surgical and histopathological findings were correlated with the ultrasound (US) findings; in patients who did not have surgery the reference standard was the clinical consensus based on follow-up.

RESULTS: Thirty-four patients out of 179 with abnormal sonographic findings did not undergo appendicectomy and recovered spontaneously; in 22 of these, the US changes were confined to the appendiceal tip. A normal appendix was identified in 537 patients (45.9% of all patients without appendicitis), with histologic verification subsequently obtained in 21. In 76 normal appendices (14.2% out of all normal appendices), luminal dilatation due to non-expressible inspissated faeces resulted in appendiceal outer diameter >6 mm (range, 6.2-12 mm); a histopathologic proof of non-inflamed appendix was obtained in seven of these.

CONCLUSIONS: A normal appendix can be visualized in a high percentage of cases and it may present with an outer diameter >6 mm (the widely-accepted upper limit of normal) due to the inspissated faecal material within the lumen. A significant percentage of early appendicitis can resolve spontaneously, especially when confined to the appendiceal tip.

LABORATORY MARKERS  
C-REACTIVE PROTEIN  



Leucocyte count and C-reactive protein in the diagnosis of acute appendicitis.

Gronroos JM, Gronroos P.

Department of Surgery, University of Turku, Turku, Finland.

 

Br J Surg 1999 Apr;86(4):501-4 Abstract quote

BACKGROUND: The aim of the present work was to study the preoperative leucocyte counts and C-reactive protein (CRP) values in three groups of patients operated on for a clinical suspicion of acute appendicitis with different findings at appendicectomy: an uninflamed appendix, uncomplicated acute appendicitis or complicated acute appendicitis. In particular, patients with acute appendicitis but a normal leucocyte count and CRP level were sought.

METHODS: In this retrospective study, the mean preoperative leucocyte count and CRP value in 100 consecutive patients with an uninflamed appendix (group A), in 100 consecutive patients with uncomplicated acute appendicitis (group B) and in 100 consecutive patients with complicated acute appendicitis (group C) were calculated. The numbers of patients with (1) both values normal, (2) only leucocyte count raised, (3) only CRP level raised and (4) both values raised were calculated in each of the three groups. Results: The increase in leucocyte count was an early marker of appendiceal inflammation, whereas the CRP value increased markedly only after appendiceal perforation or abscess formation. Group A (uninflamed appendix) contained 24 patients in whom both values were normal. Neither group B (uncomplicated acute appendicitis) nor group C (complicated acute appendicitis) contained any patient with both values in the normal range.

CONCLUSION: Acute appendicitis is very unlikely when both the leucocyte count and CRP value are normal.

LEUKOCYTOSIS  


White blood cell count is a poor predictor of severity of disease in the diagnosis of appendicitis.

Coleman C, Thompson JE Jr, Bennion RS, Schmit PJ.

Olive View-University of California at Los Angeles Medical Center, Sylmar 91342, USA.


Am Surg 1998 Oct;64(10):983-5 Abstract quote

The white blood cell (WBC) count is considered to be a useful test in the diagnosis of appendicitis.

The purpose of this study was to examine the clinical features of patients with normal WBC appendicitis and also to determine whether a higher WBC count correlates with a more advanced stage of appendicitis. Patients with pathologically confirmed appendicitis from January 1989 to December 1994 were included in the study (n = 1919).

The age, gender, temperature, length of hospital stay, and severity of disease (1 = acute appendicitis; 2 = gangrenous appendicitis; 3 = perforated appendicitis with abscess formation; 4 = appendicitis with diffuse peritonitis) were compared for patients with a normal WBC count (range, 3.8-10.9) versus those who had an elevated WBC count. A normal WBC count was seen in 11 per cent of patients (n = 209). There was no difference in age, temperature, gender, or severity of disease in the patients with a normal WBC count compared with those with an elevated WBC count (P > 0.05). The severity of disease of patients with a normal WBC count were: 1 = 58 per cent; 2 = 13 per cent; 3 = 7 per cent; and 4 = 22 per cent. For patients with an elevated WBC count the scores were: 1 = 57 per cent; 2 = 17 per cent; 3 = 13 per cent; and 4 = 14 per cent.

The proportion of gangrenous and perforated appendicitis in the patients with a normal WBC count is the same as in the patients with an elevated WBC count.

 

GROSS APPEARANCE/
CLINICAL VARIANTS
CHARACTERIZATION
GENERAL  


Surgical pathology of acute appendicitis.

Butler C.


Hum Pathol 1981 Oct;12(10):870-8 Abstract quote

Pathologic findings and clinicopathologic correlations in 276 consecutive appendectomies performed in a university hospital are reviewed. In 59 cases, appendectomy was incidental to another elective procedure. In the other 217 cases exploration was performed as an emergency, and acute appendicitis was present in 160 of the cases (74 per cent); 54 of these were complicated by perforation. In the remaining 57 cases there was either some other pathologic process clinically distinct from appendicitis or no identifiable source of the preoperative symptoms.

The major findings were as follows: (1) Although appendicitis appears to be the result of initial mucosal injury, not all inflamed appendices show clear evidence of lumen obstruction by a fecalith or another mechanism. (2) Perforation, which greatly increases the morbidity in appendicitis and disproportionately affects children, is the consequence of transmural necrosis and is related much more to prolonged symptoms prior to surgery than to the presence of a fecalith or any other evidence of lumen obstruction. (3) The clinical course of appendicitis varies enormously, and the duration of symptoms has a wide range that is partly independent of the pathologic findings (which may include evidence of considerable chronic inflammation).

The conclusions are that the current widely accepted practice of prompt exploration on suspicion of appendicitis is fully justified, that the inflammation in appendicitis may have quite different rates of progression from patient to patient, and that the etiopathogenesis of appendicitis may not be uniform and in some cases may involve important immunologic factors.

VARIANTS  
GROSSLY NORMAL APPENDIX  


Should an appendix that looks 'normal' be removed at diagnostic laparoscopy for acute right iliac fossa pain?

Teh SH, O'Ceallaigh S, Mckeon JG, O'Donohoe MK, Tanner WA, Keane FB.

Department of Surgery, The Adelaide and Meath Hospital, Dublin, Ireland.

Eur J Surg 2000 May;166(5):388-9 Abstract quote

OBJECTIVE: To find out whether the removal of the appendix from patients in whom laparoscopy for acute right iliac fossa pain shows no abnormality is justified to avoid the risk of missing acute appendicitis.

PATIENTS: The records of patients who, between 1990 and 1997 had emergency laparoscopy for acute right iliac fossa pain were reviewed. Only those in whom laparoscopy had shown no abnormality and had not had the appendix removed were included in the study.

METHODS: Outcome was assessed by telephone questionnaire to the patient, the general practitioner, or both.

RESULTS: Emergency laparoscopy had been done for 254 patients. No abnormality was detected in 41. Full follow up was available on 34 patients (83%). 21 patients have remained entirely free of symptoms. Of the 13 patients who had recurrent symptoms, 2 subsequently had a histologically normal appendix removed, yet still had symptoms; 2 had a second laparoscopy that showed no abnormality; 5 had ultrasound; and 4 had colonoscopy or a barium enema examination.

CONCLUSION: Removal of an appendix that looks 'normal' at emergency laparoscopy for right iliac fossa pain is unjustified.

 

HISTOLOGICAL TYPES CHARACTERIZATION
GENERAL  


Histopathology of interval (delayed) appendectomy specimens: strong association with granulomatous and xanthogranulomatous appendicitis.

Guo G, Greenson JK.

 

Am J Surg Pathol. 2003 Aug;27(8):1147-51. Abstract quote

Patients who present with a ruptured acute appendicitis are often treated with antibiotic therapy and drainage followed by a delayed or interval appendectomy. We noticed interval appendectomy specimens with granulomatous inflammation and postulated that interval appendectomy may lead to granulomatous appendicitis.

To test this hypothesis, we reviewed the histopathology of all interval appendectomy specimens within a 4-year period and compared them with a control group of patients who had acute appendicitis and underwent routine acute appendectomy. All slides were randomized and reviewed blindly to assess the inflammatory patterns, with special attention given to the presence of granulomas and other Crohn-like features.

Twenty-two cases of interval appendectomy were found. The interval between symptom onset and appendectomy ranged from 30 to 95 days with a mean of 58 days, whereas all 44 control patients had surgery within 72 hours of symptoms onset. Thirteen (59.1%) of the 22 interval appendectomy cases contained granulomas compared with only 3 of 44 controls (P < 0.0001). Eight (36.4%) of the interval appendectomy cases had xanthogranulomatous inflammation compared with none in the acute appendicitis group (P < 0.0001). A Crohn-like appearance was seen in 11 (50.0%) of the interval appendectomy cases and 1 of the controls (P < 0.0001). Follow-up data were available in 8 of 11 cases with Crohn-like features; none developed Crohn disease during an average follow-up period of 23 months.

Delayed or interval appendectomy specimens often have a characteristic inflammatory pattern that includes granulomas, xanthogranulomatous inflammation, mural fibrosis/thickening, and transmural chronic inflammation. Without the appropriate clinical history, these changes may be misinterpreted as Crohn disease.


Neutrophil count in the normal appendix and early appendicitis: Diagnostic index of real acute inflammation.

Barcia JJ, Reissenweber N.

Catedra de Anatomia Patologica, Hospital de Clinicas Dr. Manuel Quintela, Facultad de Medicina, Montevideo, Uruguay; Departamento de Histologia y Embriologia, Facultad de Medicina, Montevideo, Uruguay.

 

Ann Diagn Pathol 2002 Dec;6(6):352-6 Abstract quote

It is generally accepted that the uninflammed appendix does not contain neutrophils. In view of that, we searched for the presence of neutrophils in 60 uninflammed appendectomies and compared the findings with the neutrophil count in 20 cases of early appendicitis.

In the uninflammed appendix, the upper third of the mucosa showed a mean of 0.75 neutrophils (N) per 5 high power fields (HPF), 4.71 N/5 HPF in the middle third, and 2.70 N/5 HPF in the deep third. At the suberosa, a mean of 3.41 and 3.32 N per 10 post-capillary venules in respectively longitudinal and transverse sections of the organ were present. The number of neutrophils in the mucosa showed a positive correlation with the number in the subserosa. In the early appendicitis we observed a mean of 12.53 N/5 HPF in the upper third, 11.33 N/5 HPF in the middle third, and 13.0 N/5 HPF in the deep third; at the subserosa, a mean of 4.95 N/10 post-capillary venules in transverse sections and 4.45 N/10 post-capillary venules in longitudinal sections was observed. No positive correlation between N in the mucosa and subserosa was observed. The count of N in the mucosa of normal appendix and early appendicitis showed a significant difference (P <.005).

We conclude that, although present, not more than 10 neutrophils/5 HPF are found in the mucosa of uninflammed appendixes. Neutrophil count in the lamina propria should support the diagnosis of "normal" appendix and could be an indicator for suspecting early appendicitis, preventing underdiagnosis.


The neutrophil count in childhood acute appendicitis.

Doraiswamy NV.

Br J Surg 1977 May;64(5):342-4 Abstract quote

A study was made of the total leucocyte count, neutrophil percentage and absolute neutrophil count in 100 consecutive children with acute appendicitis and in 25 children from whom, following a provisional diagnosis of acute appendicitis, a normal appendix had been removed, no other infective or inflammatory lesion having been found.

In the first group there was a raised total leucocyte count in 42 per cent, a raised neutrophil percentage in 93 per cent and a raised absolute neutrophil count in 77 per cent. In the second group the corresponding figures were 4, 24 and 16 per cent. Acute appendicitis is associated with changes in the total leucocyte and neutrophil counts and a correct interpretation of the results of these investigations requires that account be taken of the age of each child. A probable maximum absolute neutrophil count has been calculated.

An explanation has been suggested for the presence of normal total leucocyte counts in certain cases in spite of acute appendicitis.

VARIANTS  
RESOLVING ACUTE APPENDICITIS  


Histological features of resolving acute, non-complicated phlegmonous appendicitis.

Ciani S, Chuaqui B.

Department of Pathology, School of Medicine, Catholic University of Chile, Santiago, Chile.

Pathol Res Pract 2000;196(2):89-93 Abstract quote

The histological features of resolving acute appendicitis are described. Formalin-fixed, paraffin-embedded appendices of 200 cases with acute, non-complicated phlegmonous appendicitis were reviewed.

In 80 out of 200 cases, a histological picture characterized by a predominantly lymphocytic infiltrate of the subserosa and muscularis propria or the subserosa alone was found. In the affected muscularis propria, eosinophils were admixed with lymphocytes, and the cellular infiltrate showed a lesser degree than that of the classic phlegmonous appendicitis. A multifocal, rather than a diffuse pattern of infiltration was observed.

Cases were divided into three groups. Group 1: appendices with the typical features of phlegmonous appendicitis: 120 cases, 60%. Group 2: appendices with a predominantly lymphocytic infiltrate in the muscularis propria, subserosa, or both, and no granulation tissue: 65 cases, 32.5%. Group 3: appendices with granulation tissue: 15 cases, 7.5%. Complicated appendicitis was excluded. Data on the duration of the clinical symptoms were derived from the clinical history. The differences between the mean duration time of groups 1 and 2, and of groups 2 and 3 were statistically significant.

The findings support the contention that a mixed infiltrate of lymphocytes and eosinophils represents a regression phase of acute appendicitis.

 

DIFFERENTIAL DIAGNOSIS KEY DIFFERENTIATING FEATURES
MESENTERIC ADENITIS  


Mesenteric adenitis: CT diagnosis of primary versus secondary causes, incidence, and clinical significance in pediatric and adult patients.

Macari M, Hines J, Balthazar E, Megibow A.

Department of Radiology, Abdominal Imaging, NYU Medical Center, Tisch Hospital, 560 First Ave., Ste. HW 206, New York, NY 10016, USA.

 

AJR Am J Roentgenol 2002 Apr;178(4):853-8 Abstract quote

OBJECTIVE: Our objective was to determine the clinical significance of mesenteric adentitis when detected on CT.

MATERIALS AND METHODS: Mesenteric adenitis was considered present if a cluster of three or more lymph nodes measuring 5 mm or greater each was present in the right lower quadrant mesentery. If no other abnormality was detected on CT, then mesenteric adenitis was considered primary. If a specific inflammatory process was detected in addition to the lymphadenopathy, then mesenteric adenitis was considered secondary. Patients with a known neoplasm or HIV infection were excluded. Three separate groups of patients were examined for the presence and cause of mesenteric adenitis. Group 1 consisted of 60 consecutive patients prospectively identified with mesenteric adenitis on CT examinations. Group 2 consisted of 60 consecutive patients undergoing abdominal and pelvic CT for evaluation of blunt or penetrating abdominal trauma. Group 3 consisted of 60 consecutive patients undergoing abdominal and pelvic CT with acute abdominal symptoms. In all patients, the indication for imaging was documented, and the size of the largest lymph node, when present, was measured. In patients with mesenteric adenitis, the CT findings, clinical history, and clinical or surgical follow-up were subsequently evaluated to determine the cause of mesenteric adenitis.

RESULTS: In the 60 patients prospectively identified with CT findings of mesenteric adenitis (group 1), 18 (30%) of 60 had primary mesenteric adenitis. The remaining 42 patients (70%) had an associated inflammatory condition that was established on CT as the likely cause of mesenteric adenitis. Mesenteric adenitis was present in none (0%) of the 60 patients in group 2 and in five (8.3%) of 60 patients in group 3.

CONCLUSION: The incidence of mesenteric adenitis in patients with and those without abdominal pain is low. When evidence of mesenteric adenitis is present on CT examinations, usually a specific diagnosis can be established as its cause.

 

PROGNOSIS AND TREATMENT CHARACTERIZATION
PROGNOSTIC FACTORS  
EARLY INTERVENTION  


Outcome of elderly patients with appendicitis: effect of computed tomography and laparoscopy.

Hui TT, Major KM, Avital I, Hiatt JR, Margulies DR.

Department of Surgery, Cedars-Sinai Medical Center, 8700 Beverly Blvd, Los Angeles, CA 90048, USA.

Arch Surg 2002 Sep;137(9):995-8 Abstract quote

HYPOTHESIS: Elderly patients who have appendicitis have a greater morbidity and mortality rate when compared with younger patients. We hypothesized that recent changes in the diagnosis and management of appendicitis in elderly patients might affect the outcome.

DESIGN: Retrospective review.

SETTING: Large metropolitan teaching hospital.

PATIENTS: All patients aged 70 years and older who underwent appendectomy for appendicitis between January 1, 1991, and December 31, 2000, were divided into groups 1 (those treated from January 1, 1991, through December 31, 1995) and 2 (those treated from January 1, 1996, through December 31, 2000).

MAIN OUTCOME MEASURES: Age, sex, preoperative evaluation, operative duration and findings, postoperative course, duration of hospital stay, and mortality rate. Continuous and categorical variables were analyzed using t and chi(2) tests, respectively.

RESULTS: Ninety-five patients met inclusionary criteria. The mean age (78 years), sex, preoperative suggestion of appendicitis (group 1, 39 [83%] of 47 patients; group 2, 45 [94%] of 48 patients), and duration of the preoperative hospitalization over 24 hours (group 1, 11 patients [23%]; group 2, 9 patients [19%]) were similar in both groups. There was an increasing use of diagnostic computed tomography (group 1, 13 patients [28%]; group 2, 32 patients [67%]; P<.001) and laparoscopy (group 1, 14 patients [30%]; group 2, 23 patients [48%]; P =.02) between the 2 study periods associated with no significant difference in the duration of hospitalization, frequency of appendiceal perforation or abscess, occurrence of complications, or mortality. The length of operating time increased in the second period (ie, January 1, 1996, through December 31, 2000).

CONCLUSIONS: Appendicitis in elderly patients continues to be a challenging surgical problem. While computed tomography may represent a useful diagnostic tool and laparoscopic appendectomy may be appropriate therapy for selected patients, neither has affected outcome when measured for morbidity and mortality rates. Overall results might improve with earlier consideration of the diagnosis in elderly patients with abdominal pain, followed by prompt surgical consultation and operation.

INFECTION  


Standardized patient care guidelines reduce infectious morbidity in appendectomy patients.

Helmer KS, Robinson EK, Lally KP, Vasquez JC, Kwong KL, Liu TH, Mercer DW.

Department of Surgery, The University of Texas-Houston Medical School and LBJ General Hospital, 5656 Kelley St., Ste. 3-OS 62008, Houston, TX 77026, USA.

Am J Surg 2002 Jun;183(6):608-13 Abstract quote

BACKGROUND: Surgical wound infection and intra-abdominal abscess remain common infectious complications after appendectomy, especially in the setting of a perforated or gangrenous appendix. We therefore developed a clinical protocol for the management of appendicitis to decrease postoperative infectious complications.

METHODS: Between January 1, 1999, and December 31, 1999, 206 patients with appendicitis were treated on protocol. Retrospectively, the charts were reviewed for all protocol patients as well as for 232 patients with appendicitis treated in the year prior to protocol initiation. Data were collected on surgical wound infections and intra-abdominal abscesses.

RESULTS: There were significantly fewer infectious complications in the protocol group than in the nonprotocol group (20 [9%] versus 8 [4%]; P <0.05). In patients with a perforated or gangrenous appendix, the infectious complication rate was reduced from 33% to 13% (P <0.05).

CONCLUSIONS: The incidence of infectious complications after appendectomy can be significantly reduced with a standardized approach to antibiotic therapy and wound management.

PERFORATION  


A new perspective in appendicitis: calculation of half time (T(1/2)) for perforation.

Redmond JM, Smith GW, Wilasrusmee C, Kittur DS.

Department of Surgery, The Johns Hopkins Medical Institutions, Balitmore, Maryland, USA.

 

Am Surg 2002 Jul;68(7):593-7 Abstract quote

Appendicitis is generally a more serious disease in the elderly than in the young. In the former, perforation is seen commonly leading to the belief that the appendix perforates more readily and rapidly in the elderly. A competing view is that the appendix perforates relatively more frequently in the elderly than in the young.

To distinguish between these two views we analyzed 126 cases of acute appendicitis stratified by age group. The time between onset of symptoms and perforation was calculated with a novel method that utilized the biological concept of T(1/2) for perforation. Our findings suggest that the rate of perforation in the elderly is not significantly different from that in the young but the frequency of perforation is higher in the elderly.

We concluded that appendicitis carries a graver prognosis in the elderly because the frequency of appendiceal perforation is higher in the elderly.

TREATMENT  
ANTIBIOTIC  
Optimum duration of prophylactic antibiotics in acute non-perforated appendicitis.

Mui LM, Ng CS, Wong SK, Lam YH, Fung TM, Fok KL, Chung SS, Ng EK.

Department of Surgery, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong.
ANZ J Surg. 2005 Jun;75(6):425-8. Abstract quote  

Background: The effect of extended prophylactic antibiotic therapy on postoperative infective complications such as wound infection and intra-abdominal abscess for non-perforated appendicitis is poorly defined.

Methods: In a randomized controlled trial of 269 patients aged 15-70 years with non-perforated appendicitis undergoing open appendicectomy; 92 received single dose preoperative (group A), 94 received three-dose (group B) and 83 received 5-day perioperative (group C) regimens of cefuroxime and metronidazole. Postoperative infective complication was the primary endpoint. Secondary outcomes included length of hospital stay and complications related to antibiotic therapy.

Results: The rate of postoperative infective complication was not significantly different among the groups (6.5% group A, 6.4% group B, 3.6% group C). The duration of antibiotic therapy had no significant effect on the length of hospital stay. Complications related to antibiotic treatment were significantly more common for 5-day perioperative antibiotic group (C) compared with single dose preoperative antibiotic group (A) (P = 0.048).

Conclusion: Single dose of preoperative antibiotics is adequate for prevention of postoperative infective complications in patients with non-perforated appendicitis undergoing open appendicectomy. Prolonging the use of antibiotics can lead to unnecessary antibiotic related complications.
LAPAROSCOPIC SURGERY  


Laparoscopic appendicectomy: review of 331 cases over 7 years, in a Saudi Arabian hospital.

Tucker O, Rashid Al-Faqih S, El-Amin O, Zaki A.

St. James's Hospital, Dublin, Ireland.

 

Endoscopy 2002 Aug;34(8):639-42 Abstract quote

BACKGROUND AND STUDY AIMS: Laparoscopic appendicectomy had been well established by Semm before the popular breakthrough of laparoscopic cholecystectomy. The aim of this study was to evaluate the role of laparoscopy in the diagnosis and treatment of acute appendicitis.

PATIENTS AND METHODS: This is a retrospective study. Patients with signs and symptoms of suspected appendicitis necessitating surgery were selected for laparoscopic management between 1992 and 1999.

RESULTS: A total of 331 patients were recruited into the study, 184 (56 %) male and 147 (44 %) female. The appendix was successfully removed laparoscopically in 98 % of the patients. The median operating time was 63.3 minutes, and 93 % of the appendices removed were histologically abnormal. Postoperative complications occurred in 19 patients (6 %), and included wound infection (1 %), enterocutaneous fistula, pelvic abscess, hemorrhage, urinary tract infection, respiratory tract infection, incisional herniae and pain at trocar sites. The mean hospital stay was 2.31 days (range 1 - 10 days).

CONCLUSION: Laparoscopic appendicectomy is a safe procedure with low morbidity. It is advantageous in obese patients, patients with other pathology, and patients with an unusual position of the appendix, and it has a low infection rate.

SURGERY  
Ten-year experience with pediatric laparoscopic appendectomy--are we getting better?

Phillips S, Walton JM, Chin I, Farrokhyar F, Fitzgerald P, Cameron B.

Division of Pediatric Surgery, McMaster Children's Hospital, Hamilton, Ontario, Canada L8N 3Z5.
J Pediatr Surg. 2005 May;40(5):842-5. Abstract quote  

BACKGROUND/PURPOSE: The purpose of this study was to compare our initial (1994-1997) and recent (2001-2003) experiences in laparoscopic appendectomy (LA).

METHODS: A 2-year (2001-2003) retrospective chart review of cases of appendicitis was performed and compared with data obtained from 1994 to 1997 cases. Operating and anesthetic times as well as postoperative outcomes were analyzed. Cases of conversion to open appendectomy were included in the analysis.

RESULTS: Two hundred and thirty-three LA cases from 2001 to 2003 were compared with 119 cases from 1994 to 1997. Operating time decreased significantly from 58 to 47 minutes in acute appendicitis (AA) and from 80 to 58 minutes in perforated appendicitis (PA). Anesthetic time decreased significantly in both AA (82 to 71 minutes) and PA (106 to 84 minutes). There were significant decreases in the conversion rate in PA (23.4% to 3.5%), although no change was seen in AA. In PA, the incidence of postoperative abscess decreased from 36.2% to 16.5%. There was no significant decrease in length of stay, amount of analgesia used, time to resume regular diet, or incidence of wound infections and bowel obstructions.

CONCLUSIONS: Ten years of experience in LA has resulted in decreases in anesthetic and operating times for AA and PA as well as decreases in the incidence of abscesses and conversion rates.


To leave or not to leave? A retrospective review of appendectomy during diagnostic laparoscopy for chronic pelvic pain.

Chandler B, Beegle M, Elfrink RJ, Smith WJ.

University of Health Sciences, Kansas City, USA.

Mo Med 2002 Sep-Oct;99(9):502-4 Abstract quote

Chronic pelvic pain in females is a common symptom encountered by family practitioners, gynecologists, gastroenterologists, and general surgeons.

In this study, we retrospectively reviewed the charts of 22 female patients who had chronic pelvic pain or acute exacerbation of chronic pelvic pain. None had signs of appendicitis. All were treated with a diagnostic laparoscopy with appendectomy.

Of the 22 patients, 20 had complete relief of their pain; 17 had an abnormal histopathological diagnosis of their appendices.

Henry JB. Clinical Diagnosis and Management by Laboratory Methods. Twentieth Edition. WB Saunders. 2001.
Rosai J. Ackerman's Surgical Pathology. Ninth Edition. Mosby 2004.
Sternberg S. Diagnostic Surgical Pathology. Fourth Edition. Lipincott Williams and Wilkins 2004.
Robbins Pathologic Basis of Disease. Seventh Edition. WB Saunders 2005.
DeMay RM. The Art and Science of Cytopathology. Volume 1 and 2. ASCP Press. 1996.
Weedon D. Weedon's Skin Pathology Second Edition. Churchill Livingstone. 2002
Fitzpatrick's Dermatology in General Medicine. 5th Edition. McGraw-Hill. 1999.
Weiss SW and Goldblum JR. Enzinger and Weiss's Soft Tissue Tumors. Fourth Edition. Mosby 2001.


Commonly Used Terms

Basic Principles of Disease
Learn the basic disease classifications of cancers, infections, and inflammation

Commonly Used Terms
This is a glossary of terms often found in a pathology report.

Diagnostic Process
Learn how a pathologist makes a diagnosis using a microscope

Surgical Pathology Report
Examine an actual biopsy report to understand what each section means

Special Stains
Understand the tools the pathologist utilizes to aid in the diagnosis

How Accurate is My Report?
Pathologists actively oversee every area of the laboratory to ensure your report is accurate

Got Path?
Recent teaching cases and lectures presented in conferences


Internet Links

Last Updated June 17, 2005

Send mail to The Doctor's Doctor with questions or comments about this web site.
Read the Medical Disclaimer.

Copyright © The Doctor's Doctor