Granulomatous appendicitis and the appendix in idiopathic inflammatory bowel disease

Yersinia enterocolitica in Crohn’s disease

Increasing attention is being paid to the unique roles gut microbes play in both physiological and pathological processes. Crohn’s disease (CD) is a chronic, relapsing, inflammatory disease of the gastrointestinal tract with unknown etiology. Currently, gastrointestinal infection has been proposed as one initiating factor of CD. Yersinia enterocolitica, a zoonotic pathogen that exists widely in nature, is one of the most common bacteria causing acute infectious gastroenteritis, which displays clinical manifestations similar to CD. However, the specific role of Y. enterocolitica in CD is controversial. In this Review, we discuss the current knowledge on how Y. enterocolitica and derived microbial compounds may link to the pathogenesis of CD. We highlight examples of Y. enterocolitica-targeted interventions in the diagnosis and treatment of CD, and provide perspectives for future basic and translational investigations on this topic.

Oncological Safety and Potential Cost Savings of Routine vs Selective Histopathological Examination After Appendectomy: Results of the Multicenter, Prospective, Cross-Sectional FANCY Study

OBJECTIVE

To investigate the oncological safety and potential cost savings of selective histopathological examination after appendectomy.

BACKGROUND

The necessity of routine histopathological examination after appendectomy has been questioned, but prospective studies investigating the safety of a selective policy are lacking.

METHODS

In this multicenter, prospective, cross-sectional study, inspection and palpation of the (meso)appendix was performed by the surgeon in patients with suspected appendicitis. The surgeon's opinion on additional value of histopathological examination was reported before sending all specimens to the pathologist. Main outcomes were the number of hypothetically missed appendiceal neoplasms with clinical consequences benefiting the patient (upper limit two-sided 95% confidence interval below 3:1000 considered oncologically safe) and potential cost savings after selective histopathological examination.

RESULTS

Seven thousand three hundred thirty-nine patients were included. After a selective policy, 4966/7339 (67.7%) specimens would have been refrained from histopathological examination. Appendiceal neoplasms with clinical consequences would have been missed in 22/4966 patients. In 5/22, residual disease was completely resected during additional surgery. Hence, an appendiceal neoplasm with clinical consequences benefiting the patient would have been missed in 1.01:1000 patients (upper limit 95% confidence interval 1.61:1000). In contrast, twice as many patients (10/22) would not have been exposed to potential harm due to re-resections without clear benefit, whereas consequences were neither beneficial nor harmful in the remaining seven. Estimated cost savings established by replacing routine for selective histopathological examination were €725,400 per 10,000 patients.

CONCLUSIONS

Selective histopathological examination after appendectomy for suspected appendicitis is oncologically safe and will likely result in a reduction of pathologists' workload, less costs, and fewer re-resections without clear benefit.

Characteristics and Outcomes of Left-sided Ulcerative Colitis With a Cecal/Periappendiceal Patch of Inflammation

Ulcerative colitis (UC) is characterized by continuous mucosal inflammation of the rectum, extending uninterrupted to a variable portion of the colon proximally. However, in some patients with distal colitis, a distinct pattern of skip inflammation (so-called patch) involves the cecum and/or appendiceal orifice, but data on this entity are contradictory, and its significance and prognosis are still debated. We identified 102 adult cases of left-sided UC with a cecal/periappendiceal patch and compared them to 102 controls (left-sided UC only) along clinicopathologic characteristics and disease outcomes. In multivariate analysis, patients with a patch were younger (median age: 31 vs. 41 y; P =0.004) and more likely to have rectosigmoid involvement only (58.8% vs. 28.4%; P <0.001), compared with patients without a patch. During follow-up, patients with a patch were more likely to be eventually diagnosed with Crohn disease (CD) (9.8% vs. 1.0%; P =0.022) and to show proximal extension of inflammation (35.6% vs. 10.0%; P =0.021), but showed no differences in rates of neoplasia, colectomy, or pharmacotherapy escalation. Kaplan-Meier analysis confirmed that patients with a biopsy diagnosis of cecal/periappendiceal patch were more likely to show proximal disease extension ( P <0.001) and to be diagnosed with CD ( P =0.008). In conclusion, cecal/periappendiceal skip inflammation in left-sided UC occurs more often in younger patients and in those with rectosigmoid involvement and is associated with proximal disease extension and, in a small fraction of cases, change of diagnosis to CD. However, it does not portend increased risk of neoplasia, pharmacotherapy escalation, or subsequent colectomy, compared with patients with left-sided UC only.

Crohn Disease Infrequently Affects the Appendix and Rarely Causes Granulomatous Appendicitis

Data from previous studies suggest Crohn disease of the appendix accounts for ∼25% of granulomatous appendicitis cases. However, we have found that granulomatous inflammation in appendectomy specimens rarely heralds Crohn disease. We suspect that appendiceal involvement by Crohn disease is uncommon, even when patients have severe ileocolonic inflammation. We performed this study to determine the prevalence and nature of appendiceal inflammation among patients with Crohn disease. We reviewed 100 ileocolic specimens with strictures and fistulizing Crohn disease for the nature and distribution of inflammatory changes in the appendix and compared them with 100 appendices on colectomy specimens from age-matched and sex-matched patients with ulcerative colitis. We also evaluated 27 additional cases of granulomatous appendicitis in appendectomy specimens to determine the frequency with which this finding represented Crohn disease. The appendix was usually normal (26%) or showed fibrous obliteration (50%) in ileocolic resection specimens from patients with Crohn disease. Mucosal inflammation was much less common in appendices from patients with Crohn disease than ulcerative colitis (6% vs. 28%, P<0.0001); only 4 cases contained epithelioid granulomata, 3 showed mural fibrosis and lymphoid aggregates, and 10 displayed only periappendiceal inflammation. None of the patients with granulomatous appendicitis in appendectomy specimens had, or developed, evidence of Crohn disease. We conclude that Crohn disease infrequently affects the appendix. Interval appendectomy and infection are more important considerations when appendectomy specimens feature granulomatous inflammation and/or mural lymphoid aggregates, especially if there is no history of idiopathic inflammatory bowel disease.

Pediatric hematolymphoid pathology in the gastrointestinal tract

Hematolymphoid processes involving the gastrointestinal tract in the pediatric and adolescent young adult (AYA) populations include processes occurring primarily within the gastrointestinal tract as well as systemic diseases with predilection for gastrointestinal involvement. Here, we present a focused review of reactive and neoplastic entities occurring in the pediatric and AYA age groups.

Routine histopathologic examination of the appendix after appendectomy for presumed appendicitis: Is it really necessary? A systematic review and meta-analysis

BACKGROUND

Owing to substantial costs and increasing interest in the nonoperative management of appendicitis, the necessity of routine histopathologic examination of appendectomy specimens is being questioned. The aim of this study was to determine whether routine histopathologic examination after appendectomy for suspected appendicitis should still be performed.

METHODS

PubMed, Embase, Web of Science, and the Cochrane Library were searched for studies listing the histopathologic diagnoses after appendectomy for suspected appendicitis. Main outcomes were the incidence of histopathologically proven aberrant findings, the ability of surgeons to recognize unexpected appendiceal pathology intraoperatively, and the percentage of aberrant findings resulting in a change of postoperative management. A meta-analysis was performed using a random-effects model.

RESULTS

Twenty-five studies with 57,357 patients were included. The pooled percentage of aberrant findings was 2.52% (95% confidence interval 1.81-3.51). Neoplasms were found in 0.71% (95% confidence interval 0.54-0.94). Findings of the intraoperative assessment by the surgeon were reported for 82 of the 2,718 (3.0%) unexpected diagnoses, with great variation between studies. The impact on postoperative management was described for 237 of 2,718 (8.7%) aberrant findings. Of these, 166 (70.0%) resulted in a change of postoperative management.

CONCLUSION

Based on current evidence, it remains unclear how many of the unexpected appendiceal pathologies with clinical consequences can be identified intraoperatively by the surgeon. Until reliable data on the safety and potential cost savings of a selective policy becomes available, we advise sending appendectomy specimens routinely for histopathologic examination.

Granulomatous Appendicitis in the Pediatric Population

BACKGROUND

The clinical significance of a diagnosis of granulomatous appendicitis (GA) is not well established in the pediatric population.

METHODS

Retrospective review of the etiology and histopathology of pediatric GA at 2 large pediatric institutions.

RESULTS

Forty-three (0.4%) patients had GA at a median age of 12.1 years. Twenty-two (51%) had perforated appendicitis that was medically managed prior to interval appendectomy. Sixteen of 21 noninterval appendectomies were performed for clinically suspected acute appendicitis. Among them, 1 had Crohn's disease identified during surgery. None of the other patients had a subsequent diagnosis of inflammatory bowel disease (median follow-up of 4 weeks). There were significantly more cases with mucosal-only granulomas as well as fewer serosal granulomas in the noninterval appendectomy specimens than the interval specimens (P = .014). When performed, special stains for microorganisms did not contribute to clinical care. In the same time period, GA was seen in 6 (6%) of 94 bowel resections for Crohn's disease.

CONCLUSION

GA is rare in pediatric patients, with interval appendectomy being the most common etiology and only rarely associated with Crohn's disease. Granulomas in interval appendectomies tend to be serosal-based. Special stains for infectious organisms in GA are of low diagnostic yield and have little impact on clinical management.

Acute Granulomatous Appendicitis and Lower Gastrointestinal Bleeding as the Presenting Features of Crohn's Disease

A 46-year-old woman with a history of hemorrhoids presented with right-sided abdominal pain and rectal bleeding. Preoperative imaging and intraoperative observations were suggestive of acute appendicitis. The surgical pathology of removed appendix was consistent with granulomatous appendicitis. The patient was evaluated again in two months due to persistent hematochezia and new onset of left lower quadrant abdominal pain. A diagnostic colonoscopy revealed mildly edematous mucosa in the descending colon, sigmoid colon, and rectum, and a rectal biopsy revealed patchy chronic proctitis. The biopsy of anal canal mucosa showed acute and chronic granulomatous inflammation. Based on her clinical presentation and pathology results, the diagnosis of chronic active proctitis secondary to Crohn's disease (CD) was made. There is a debate on necessity of follow-up on patients with appendiceal CD after appendectomy as previously reported appendiceal CD usually follows a benign course post-appendectomy. However, our patient's case progressed from granulomatous appendicitis to CD with severe GI bleeding and proctitis within only two months post-appendectomy. A high index of suspicion is needed in patients with a history of granulomatous appendicitis and lower GI bleeding to ensure prompt diagnosis and timely treatment.

Clinicopathologic findings in gynecologic proliferations of the appendix

Appendiceal endometriosis, endosalpingiosis, and decidual lesions have received little attention in the pathology literature, meaning their clinicopathologic features remain unclear. We identified 72 cases of appendiceal gynecologic proliferations with available slides. Clinical presentation was recorded when available, and histologic findings were correlated with clinical data. Cases included conventional endometriosis (51), endosalpingiosis (14), and decidual lesions (7). The patients with endosalpingiosis were significantly older (median 45 years) than those with endometriosis (median 34 years, P = .0085) or decidual lesions (median 31 years, P = .0088). Most endometriosis patients presented with known/suspected endometriosis (20/51, 39%), while acute appendicitis was the most common presentation for patients with endosalpingiosis (5/14, 36%) or a decidual lesion (5/7, 71%). Few patients presenting with appendicitis were ever diagnosed with extra-appendiceal disease. All 51 endometriosis cases showed both glands and stroma, and 18 (35%) had hemosiderin. One case progressed to endometrioid adenocarcinoma. Endosalpingiosis was an incidental finding in all cases, confined to the serosa in 4 and extending intramurally in 10. Four of the 7 patients with a decidual lesion were pregnant, and 2 others were taking oral contraceptives. The cases included florid decidualized endometriosis (5) and deciduosis (2). Two cases spread transmurally and effectively obliterated the appendix. Conventional appendiceal endometriosis can have several clinical presentations. Patients with it who present with acute appendicitis rarely develop it elsewhere. Appendiceal endosalpingiosis is rare and effectively incidental. Decidualized endometriosis may overtake the entire appendix.

Appendicular bleeding: an excepcional cause of lower hemorrhage

Chronic complications of acute appendicitis managed in a conservative manner are not frequent. We present a case of acute lower gastrointestinal hemorrhage in a young patient with a previous acute appendicitis without surgical intervention. The colonoscopy detected an appendicular bleeding which was surgically treated. The anatomopathological diagnosis was granulomatous appendicitis. The clinical evolution of the patient was favorable without bleeding recurrence. Appendicular hemorrhage can be an unusual complication-however potentially severe-of acute appendicitis not treated surgically.

Granulomas in the gastrointestinal tract: deciphering the Pandora's box

Granulomas are organised collection of activated histiocytes induced by a persistent antigen stimulus. A wide variety of antigens encountered by the gastrointestinal tract are of this nature and hence the resulting granulomatous inflammation represents a tissue reaction pattern. The potential causes can be broadly classified as infections or non-infectious immune reactions. There is also a group where a cause is never identified. Granulomas may be of varying morphological appearance, most commonly epithelioid, foreign body type, suppurative and necrotizing. This may provide a clue as to the aetiology; however, in most cases, the cause requires further inquiry. Pathologists may need to cut deeper levels to look for foreign material and apply special stains to look for microorganisms. Pathologists also need to be certain that the process is a true granuloma and not a mimic. The site of occurrence in the gastrointestinal tract and the clinical setting is often paramount in establishing the aetiology. For instance, infections are more likely the cause in developing countries or when there is immunosuppression. Similarly, granulomas in the stomach are usually due to Crohn's disease; however, it is only rarely the cause of granulomas isolated to the appendix.

Appendiceal Crohn’s disease clinically presenting as acute appendicitis

AIM: To determine the incidence of appendiceal Crohn’s disease (CD) and to summarize the characteristic histologic features of appendiceal CD.

METHODS: We reviewed the pathology files of 2179 appendectomy specimens from January 2007 to May 2013. The computer-assisted retrieval search facility was utilized to collect specimens. We selected those cases that were diagnosed as CD or chronic granulomatous inflammation and defined the final diagnosis according to the histologic findings of CD, including transmural lymphocytic inflammation, non-caseating epithelioid granulomas, thickening of the appendiceal wall secondary to hypertrophy of muscularis mucosa, mucosal ulceration with crypt abscesses, mucosal fissures, and fistula formation.

RESULTS: We found 12 cases (7 male and 5 female patients, with an average age of 29.8 years) of appendiceal CD. The incidence of appendiceal CD was 0.55%. The chief complaints were right lower quadrant pain, abdominal pain, lower abdominal pain, and diarrhea. The duration of symptom varied from 2 d to 5 mo. The histologic review revealed appendiceal wall thickening in 11 cases (92%), transmural inflammation in all cases (100%), lymphoid aggregates in all cases (100%), epithelioid granulomas in all cases (100%), mucosal ulceration in 11 cases (92%), crypt abscesses in 5 cases (42%), perforation in 2 cases (17%), muscular hypertrophy in 1 case (8%), neural hyperplasia in 5 cases (42%), and perpendicular serosal fibrosis in 8 cases (67%).

CONCLUSION: A typical and protracted clinical course, unusual gross features of the appendix and the characteristic histologic features are a clue in the diagnosis of appendiceal CD.

Routine histopathological examination of appendectomy specimens in children: is there any rationale?

OBJECTIVE

Primary carcinoma of the bowel is a rare malignancy in pediatric age group. The aim of the study was to assess the incidence of appendicular malignancies in children and the possibility of reducing the need for routine histopathological examination of appendix.

MATERIALS AND METHODS

In last 15 years, all the cases of appendectomies in children were analyzed. Retrospective analysis of the data was done to document the clinical presentation, diagnosis, outcome and histopathology reports of the specimen. The case files and operation notes were studied thoroughly in cases where HPR was positive for malignancy.

RESULTS

From July 1995 to June 2010, 595 appendectomies were done in children. Three cases of carcinoid tumor were detected. All were less than 1 cm and were on the tip of the appendix. There was no preoperative or intraoperative suspicion.

CONCLUSION

Routine histopathological analysis did not help in the management of any of the cases. Therefore, selective utilization of the already burdened histopathology section of the hospital would be more cost effective without affecting the patient outcome.

New insights into gastrointestinal and hepatic granulomatous disorders

Numerous diseases that involve the gastrointestinal tract reveal the presence of granulomas on histological analysis. Granulomatous diseases can be either primary or secondary to environmental factors. Granulomas are dynamic structures composed of organized collections of activated macrophages, including epithelioid and multinucleated giant cells, surrounded by lymphocytes. The formation of granulomas is usually in response to antigenic stimulation and is orchestrated through cytokines, immune cells and host genetics. In this Review, the pathogenesis and etiologies of granulomas of the gastrointestinal tract and liver are discussed, as are the available diagnostic tools to help differentiate their various underlying etiologies. In addition, the role of granulomas in harboring latent tuberculosis is reviewed. The effects of tumor necrosis factor antagonists and interferon-α on the development of granulomas are also discussed.

Infectious causes of appendicitis

The pathologic spectrum of the inflamed appendix encompasses a wide range of infectious entities, some with specific histologic findings, and others with nonspecific findings that may require an extensive diagnostic evaluation. The appendix is exclusively involved in some of these disorders, and in others may be involved through extension from other areas of the gastrointestinal tract. This review discusses the pathologic features of bacterial, viral, fungal, and parasitic infections affecting the appendix, including adenovirus; cytomegalovirus; Yersinia, Actinomyces, Mycobacterium, or Histoplasma species; Enterobius vermicularis; schistosomiasis; and Strongyloides stercoralis. Pertinent ancillary diagnostic techniques and the clinical context and significance of the various infections are also discussed.

Granulomatous appendicitis in a 12-year-old boy

Isolated granulomatous inflammation of the appendix is extremely rare, and its etiology is still unknown. We describe a 12-year-old boy with isolated granulomatous appendicitis where the etiology could not be clarified despite infectious criteria such as high fever and gastroenteritis. Children with epithelioid granulomatous appendicitis have a good prognosis following appendectomy.

Granulomatous diseases and granulomas of the appendix

Granulomatous appendicitis is a rare phenomenon. Idiopathic (primary) granulomatous appendicitis is very rare. It is a diagnosis by exclusion. There are many etiologies, both infectious and noninfectious, for secondary granulomatous appendicitis. Isolated appendiceal Crohn's disease (CD) is no longer an accepted explanation of idiopathic granulomatous appendicitis, but rather, it is thought to be part of more generalized gastrointestinal CD. Yersinia infection and CD constitute the main etiology of granulomatous appendicitis in the West. Infectious causes, mainly tuberculosis and parasitic infestations, are the main culprits in tropical and subtropical countries. This variation is probably a result of differences in the geographical distribution of these diseases. Recently, interval appendectomy has been suggested as an important cause of granulomatous appendicitis. The importance of interval appendectomy may vary according to the local practice of this procedure in each region. Other unusual causes may include sarcoidosis and foreign body reaction, mainly as a result of vegetable matter from feces. A review study of 3381 appendectomy specimens over a 4-year period showed only 13 cases (0.38%) of granulomatous appendicitis. Infectious and noninfectious causes were responsible for 62% and 38% of granulomatous appendicitis, respectively. Parasites alone were responsible for 38.5% of the cases. Interval appendectomy and CD each contributed 15% and 8%, respectively, of the total etiology. Granulomatous appendicitis was more common in young adult males.

Prior appendectomy and the phenotype and course of Crohn's disease

AIM

To determine whether prior appendectomy modifies the phenotype and severity of Crohn's disease.

METHODS

Appendectomy status and smoking habits were specified by direct interview in 2838 patients consecutively seen between 1995 and 2004. Occurrence of complications and therapeutic needs were reviewed retrospectively. Additionally, annual disease activity was assessed prospectively between 1995 and 2004 in patients who had not had ileocecal resection and of a matched control group.

RESULTS

Compared to 1770 non-appendectomized patients, appendectomized patients more than 5 years before Crohn's disease diagnosis (n=716) were more often females, smokers, with ileal disease. Cox regression showed that prior appendectomy was positively related to the risk of intestinal stricture (adjusted hazard ratio, 1.24; 95% confidence interval, 1.13 to 1.36; P=0.02) and inversely related to the risk of perianal fistulization (adjusted hazard ratio, 0.75; 95% confidence interval, 0.68 to 0.83; P=0.002). No difference was observed between the two groups regarding the therapeutic needs, except for an increased risk of surgery in appendectomized patients, attributable to the increased prevalence of ileal disease. Between 1995 and 2004, Crohn's disease was active during 50% of years in appendectomized patients (1318 out of 2637 patient-years) and 51% in non-appendectomized patients (1454 out of 2841 patient-years; NS).

CONCLUSION

Prior appendectomy is associated with a more proximal disease and has an increased risk of stricture and a lesser risk of anal fistulization. However, the severity of the disease is unaffected.