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

Xanthogranulomatous appendicitis presenting asymptomatically 3 years after surgery for hilar cholangiocarcinoma: A case report

INTRODUCTION

Xanthogranulomatous appendicitis (XGA) is a rare condition involving chronic inflammation of the appendix that is often difficult to distinguish from malignancy using imaging because of the formation of a heterogeneous mass with indistinct borders. Herein, we present a case of XGA with unusual clinical manifestations.

PRESENTATION OF CASE

A 78-year-old female patient underwent radical resection of hilar cholangiocarcinoma with extended right hepatic lobectomy and biliary reconstruction. Three years postoperatively, she presented with an irregular mass in the right lateral pelvis, which was observed on computed tomography. The patient had not experienced recent clinical symptoms and did not present with abdominal tenderness. Routine blood tests did not indicate an increased inflammatory response; however, carcinoembryonic antigen levels continued to increase. Although disseminated recurrence of hilar cholangiocarcinoma and appendiceal carcinoma were suspected, XGA was diagnosed via laparoscopic appendectomy.

DISCUSSION

XGA generally presents with symptoms of acute or chronic appendicitis, and is diagnosed incidentally during surgery. Hilar cholangiocarcinoma has a high recurrence rate, even after radical resection, and disseminated recurrence usually requires chemotherapy. In the present case, XGA was not suspected preoperatively because of the lack of physical symptoms and increased levels of tumor markers during follow-up for hilar cholangiocarcinoma. There have been no reports of XGA with such a confusing clinical course, thus confirming the difficulty in preoperatively diagnosing XGA.

CONCLUSION

The preoperative diagnosis of XGA is difficult to differentiate from malignancy because of its clinical and imaging findings. We diagnosed the patient with XGA using laparoscopic surgery.

Imaging and Clinical Findings of Xanthogranulomatous Inflammatory Disease of Various Abdominal and Pelvic Organs: A Pictorial Essay

Xanthogranulomatous (XG) inflammatory disease is a rare benign disease involving various organs, including the gallbladder, bile duct, pancreas, spleen, stomach, small bowel, colon, appendix, kidney, adrenal gland, urachus, urinary bladder, retroperitoneum, and female genital organs. The imaging features of XG inflammatory disease are nonspecific, usually presenting as a heterogeneous solid or cystic mass. The disease may also extend to adjacent structures. Due to its aggressive nature, it is occasionally misdiagnosed as a malignant neoplasm. Herein, we review the radiological features and clinical manifestations of XG inflammatory diseases in various organs of the abdomen and pelvis.

Infectious Mimics of Inflammatory Bowel Disease

Distinguishing inflammatory bowel disease (IBD) from its mimics remains a diagnostic challenge for surgical pathologists. Several gastrointestinal infections produce inflammatory patterns that overlap with typical findings of IBD. Although stool culture, PCR, and other clinical assays may identify infectious enterocolitides, these tests may not be performed or the results may be unavailable at the time of histologic evaluation. Furthermore, some clinical tests, including stool PCR, may reflect past exposure rather than ongoing infection. It is important for surgical pathologists to be knowledgeable about infections that simulate IBD in order to generate an accurate differential diagnosis, perform appropriate ancillary studies, and prompt clinical follow-up. This review covers bacterial, fungal, and protozoal infections in the differential diagnosis of IBD.

Xanthogranulomatus inflammatory lesion mimicker of malignancy: A clinicopathological study from rural India

OBJECTIVE

Xanthogranulomatus inflammation is an uncommon variant of chronic inflammation and a well-established pathological entity involving various organs and systems. It may be associated with infection and obstruction, defective lipid transport, immunological disturbances, and often confused as a malignant neoplasm. The confirmative diagnosis is made on histopathology.

METHODS

This is a retrospective study conducted from January 2008 to April 2020 on histopathologically diagnosed xanthogranulomatus lesions. All the relevant available data regarding age, sex, and organ involvement were collected from histopathology lab records. The macroscopic and microscopic evaluation of cases was also done. This study was aimed to determine the significance of histopathology in the diagnosis of xanthogranulomatus lesions, revealing pathological changes, and clinicopathological correlation.

RESULTS

In the current study, there were 93 cases of xanthogranulomatus inflammatory lesion. Gall bladder was frequently involved 70 (75.27%), followed by 5 (5.37%) kidney, gastrointestinal Tract 6 (3 [3.23%] cases in colon and 3 [3.23%] in appendix, respectively), and others. The maximum number of cases was in the age group of 31-40 years with 24 (25.80%) cases. The female to male sex ratio was 2.3:1.

CONCLUSION

Awareness and knowledge of xanthogranulomatus inflammatory lesion is significant to the pathologist and surgeon to prevent extensive surgery. This lesion often mimics as malignancy and confirmatory diagnosis is made on histopathology. Thus, every excised specimen must be examined histopathologically to diagnose and rule out differential.

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.

The Histopathology of the Appendix in Children at Interval Appendectomy

Whilst most surgeons agree that conservative treatment of appendiceal abscess in children is an adequate treatment, the need for subsequent interval appendectomy is still controversial. We analyzed the histopathology in interval appendectomy in search of signs of inflammation. All patients admitted between 2010 and 2017 with appendiceal abscess and scheduled for interval appendectomy were reviewed. The specimens were evaluated for grade of inflammation, type and distribution of cellular infiltrate, presence of necrosis or hemorrhage and infiltrate in the serosa. Forty-two patients had appendiceal abscess and were treated conservatively. Seven underwent emergent appendectomy. Thirty-three out of 35 patients underwent elective interval appendectomy. Thirty-two specimens were revised. Carcinoid tumor or other malignant lesions were not found. All of them presented some amount of inflammation, grade 1 to 2 in 53%, grade 3 to 4 in 47%. Twenty-five percent of the specimens had signs of necrosis accompanied by hemorrhage and in more than the half (53%) the infiltrate extended to the serosa. Conclusions: Although the appendix was mostly found not macroscopically inflamed intraoperatively, histology confirmed a certain grade of inflammation even months after the conservative treatment. No correlation was found between histopathologic findings and lapse of time between abscess treatment and interval appendectomy.

Xanthogranulomatous appendicitis with elevated tumor marker misdiagnosed as cecal cancer: a case report

Xanthogranulomatous inflammation is an uncommon chronic inflammatory disease that develops most often in the kidneys and gallbladder. However, xanthogranulomatous appendicitis 45eXA is rare. Herein, we present a case of XA, with an elevated tumor marker, misdiagnosed as cecal cancer. A 76-year-old woman was referred to our hospital. Carbohydrate antigen 19–9 (CA 19–9) levels were elevated. By computed tomography and magnetic resonance imaging, we diagnosed as suspected cecal cancer and performed laparoscopic-assisted ileocecal resection. The pathological diagnosis was XA. Her CA19–9 level decreased to within normal limits. XA is a condition that results from an unusual healing pattern of appendicitis. However, the underlying mechanisms are still unclear. This is the first case of XA with elevated CA 19–9 levels. In this case, XA may have had the potential for malignancy. Our case report can aid in the understanding of these rare cases and, as a result, improve their prognosis.

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.

Xanthogranulomatous appendicitis: A comprehensive literature review

BACKGROUND

Xanthogranulomatous inflammation is characterized histologically by a collection of lipid-laden macrophages admixed with lymphocytes, plasma cells, neutrophils, and often multinucleated giant cells with or without cholesterol clefts.

AIM

To review the medical literature on xanthogranulomatous appendicitis (XGA).

METHODS

We present a patient with XGA and review published articles on XGA accessed via the PubMed, MEDLINE, Google Scholar, and Google databases. Keywords used were “appendix vermiformis,” “appendectomy,” “acute appendicitis,” and “XGA.” The search included articles published before May 2020, and the publication language was not restricted. The search included letters to the editor, case reports, review articles, original articles, and meeting presentations. Articles or abstracts containing adequate information about age, sex, clinical presentation, white blood cells, initial diagnosis, surgical approach, histopathological and immunohistochemical features of appendectomy specimens were included in the study.

RESULTS

A total of 29 articles involving 38 patients with XGA, were retrospectively analyzed. Twenty (52.6%) of the 38 patients, aged 3 to 78 years (median: 34; IQR: 31) were female, and the remaining 18 (47.4%) were male. Twenty-five patients were diagnosed with acute appendicitis, ruptured appendicitis, or subacute appendicitis, and the remaining 13 patients underwent surgery for tumoral lesions of the ileocecal region. Twenty-two of the patients underwent urgent or semi-urgent surgery, and the remaining 16 patients underwent interval appendectomy.

CONCLUSION

Xanthogranulomatous inflammation rarely affects the appendix vermiformis. It is associated with significant diagnostic and therapeutic dilemmas due to its variable presentation. It is often associated with interval appendectomies, and a significant number of patients require bowel resection due to the common presentation of a tumoral lesion. XGA is usually identified retrospectively on surgical pathology and has no unique features in preoperative diagnostic studies.

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.

Post-inflammatory mucosal hyperplasia and appendiceal diverticula simulate features of low-grade appendiceal mucinous neoplasms

Post-inflammatory mucosal hyperplasia and appendiceal diverticulosis simulate mucinous neoplasms, causing diagnostic confusion. Distinction between neoplasia and its mimics is particularly important since many authorities now consider all appendiceal mucinous neoplasms to be potentially malignant. The purpose of this study was to identify clinicopathologic and molecular features that may distinguish appendiceal mucinous neoplasms from non-neoplastic mimics. We retrospectively identified 92 mucinous lesions confined to the right lower quadrant, including 55 non-neoplastic examples of mucosal hyperplasia and/or diverticulosis and 37 low-grade neoplasms. Presenting symptoms, radiographic findings, appendiceal diameter, appearances of the lamina propria, non-neoplastic crypts, and epithelium, as well as mural changes were recorded. Twenty non-neoplastic lesions were subjected to KRAS mutational testing. Non-neoplastic appendices were smaller (p < 0.05) and more likely to present with symptoms of appendicitis (p < 0.05) than neoplasms. While post-inflammatory mucosal hyperplasia and diverticula often showed goblet cell-rich epithelium, extruded mucin pools, and patchy mural alterations with fibrosis, they always contained non-neoplastic crypts lined by mixed epithelial cell types and separated by lamina propria with predominantly preserved wall architecture. On the other hand, mucinous neoplasms lacked normal crypts (p < 0.05) and showed decreased lamina propria (p < 0.05) with diffusely thickened muscularis mucosae and lymphoid atrophy. Six (30%) non-neoplastic lesions contained KRAS mutations, particularly those containing goblet cell-rich hyperplastic epithelium. We conclude that distinction between neoplastic and non-neoplastic mucinous appendiceal lesions requires recognition of key morphologic features; KRAS mutational testing is an unreliable biomarker that cannot be used to assess biologic risk or confirm a diagnosis of neoplasia.

Pathology findings following interval appendectomy: Should it stay or go?

PURPOSE

Interval appendectomy following nonoperative management of complicated appendicitis remains controversial. The aim of this study was to evaluate surgical pathology and clinical outcomes after pediatric interval appendectomy.

METHODS

Pathology results from children with complicated appendicitis who underwent interval appendectomy at a single children's hospital from 2010 to 2017 were reviewed. The primary outcome was pathology results. Secondary outcomes included complications and readmission following initial treatment and after interval appendectomy.

RESULTS

Among 149 patients (median age 11 years; range, 1-18), all had evidence of persistent inflammation on surgical pathology, 25 (17%) had an appendicolith, and no neoplasms were identified. Median duration of the initial admission was 8 days (range, 2-28) and 70% received a percutaneous drain prior to appendectomy. Interval appendectomy was performed at a median of 7.5 weeks (range, 2.9-29.1). Thirty-six (24%) returned to the hospital prior to their scheduled appendectomy and 6 (4%) required appendectomy earlier than planned. Nine patients (6%) experienced a complication following interval appendectomy, of which superficial surgical site infection was the most common (n = 4).

CONCLUSION

All children had evidence of ongoing inflammation on surgical pathology. While the clinical implications of persistent inflammation remain uncertain, these findings suggest that interval appendectomy is an appropriate treatment following medical management of complicated appendicitis in children.

LEVEL OF EVIDENCE SECTION

IV, Case series with no comparison groups.

The Impact of Pathological Criteria on Pediatric Negative Appendectomy Rate

INTRODUCTION

Negative appendectomy rate (NAR) is a quality metric used in the surgical management of appendicitis. The rates of negative appendectomy (NA) in children range anywhere from 1% to 40% in the literature. Many reports do not provide clear pathological definitions for either appendicitis or NA on which they base their calculation of NAR. We reviewed our experience with pediatric appendectomy and the pathological spectrum encompassed within our definition of a NA and examined how the pathologic definition impacts our hospital's NAR.

METHODS

A retrospective review from 2012 to 2016 in a single institution identified 1676 children that underwent appendectomy. Average age was 11.4 (2-18 years). Patient demographics, clinical outcomes and pathological findings were collected. At our institution, appendicitis is defined as the presence of transmural acute inflammation in the appendix and those patients without this finding have been considered to have had a negative appendectomy.

RESULTS

1435 patients underwent appendectomy for presumed appendicitis. The rate of pathologically diagnosed appendicitis was 91.1% (1307/1435) and as such, the NAR was 8.9% (128/1435). Review of the pathology of the NA cohort identified 67/128 (52.3%) patients with completely normal pathology. The remaining 61 patients displayed some sort of pathological abnormality including malignancy (n = 2), fecaliths (n = 9), pinworms (n = 3), granuloma (n = 2), fibrous obliteration (n = 4), isolated periappendiceal inflammation (n = 1), and acute inflammation confined to the mucosa (n = 40). Exclusion of these patients with abnormal pathology decreased the NAR to 4.6%. Patients with pathological abnormalities of the appendix other than transmural inflammation had a higher rate of 30-day readmission than patients with acute appendicitis (8.2% versus 4.5% p < 0.01).

CONCLUSION

Pediatric NAR is dependent upon the pathological definition of appendicitis and negative appendectomy. Institutional variation in definition may explain discrepancies in the literature. By example, including only those that show "the absence of inflammation or other appendiceal pathology" would decrease our NAR by 50%. This study calls into question the interpretation of interhospital NAR and the use of NAR as a quality metric in the management of appendicitis. Retrospective comparative study: Level III evidence.

Actinomyces in Crohn's-like appendicitis

AIMS

Appendicitis with a Crohn's-like histological appearance generally raises concern for Crohn's disease, Yersinia infection, and interval appendectomy. Actinomyces infection is a recognised cause of chronic appendicitis that can histologically mimic Crohn's disease.

METHODS AND RESULTS

We report on 20 cases of appendicitis with Crohn's-like histological features that were due to Actinomyces. Most patients presented with acute or chronic abdominal pain. Imaging studies suggested a mass in five cases. Two patients had interval appendectomy. Histological features showed Crohn's-like appendicitis in 16 cases, with moderate to marked fibrosis and granulomas in seven cases. The other four cases had less consistent histological findings. None of the patients developed Crohn's disease during the follow-up interval (median, 37 months).

CONCLUSIONS

Actinomyces can be associated with Crohn's-like appendicitis with marked fibrosis, transmural inflammation, lymphoid hyperplasia, and granulomas.

Not all colonic growths are malignant

We present the case of a 34-year-old woman who was diagnosed to have adenocarcinoma of the caecum based on the clinical, radiological, histopathological and intraoperative findings. However, postoperative histopathology showed only features of xanthogranulomatous inflammation without any evidence of malignancy. This benign chronic inflammatory condition could present as a histological surprise. It is important for both surgeons and pathologists alike to be aware of this.

Pulse Granulomas in Interval Appendectomy Specimens: Histochemical Identification of Cellulose Matter

Pulse granuloma is a rare pathologic condition considered to be a benign inflammatory reaction to foreign materials originated from ingested legume matter. As for pulse granulomas of the gastrointestinal tract, association with diverticular diseases is relatively common, but only a few pulse granuloma cases associated with appendicitis have been reported. This report presents histopathologic findings of pulse granuloma lesions observed in two appendectomy cases, with some histochemical examinations of cellulose matter which is reportedly a major component to provoke pulse granuloma reaction. Our patients in both cases were girls in their teens, and they underwent interval appendectomy for acute appendicitis. Both appendectomy specimens revealed ruptured walls with inflammatory granulation tissue with marked foreign body reaction including characteristic collections of ring-like, curled ribbon-like, and/or lobulated nephrosclerosis-like hyaline structures and various foreign bodies, in which microorganisms or amyloid deposition were not identified. The presence of cellulose matter was suggested by Sirius red stain, the IKI (iodine potassium iodide)-H₂SO₄ method, and birefringence by polarized light. Appendectomy materials due to acute appendicitis would include pulse granuloma reaction provoked by ingested materials with cellulose. Pathologists should be familiar with the concept and histopathologic features of pulse granulomas to avoid misinterpreting them as vascular lesions and/or amyloid deposition, or any infectious organisms.

The histopathological classification, diagnosis and differential diagnosis of mucinous appendiceal neoplasms, appendiceal adenocarcinomas and pseudomyxoma peritonei

The vermiform appendix is the primary site of several distinctive benign and malignant neoplasms. Some can produce the clinical syndrome of pseudomyxoma peritonei (PMP). A consensus on their terminology was reached by an international panel of pathologists and clinicians working under the auspices of the Peritoneal Surface Oncology Group International (PSOGI), and this review discusses the application of the PSOGI classification to routine reporting. We discuss diagnosis and differential diagnosis together with implications for patient management, covering low-grade appendiceal mucinous neoplasms, high-grade appendiceal mucinous neoplasms, serrated polyps, adenomas and adenocarcinomas. We do not cover goblet cell tumours or neuroendocrine neoplasms in this paper.

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.

Cytological diagnosis of xanthogranulomatous appendicitis

Xanthogranulomatous reaction can occur in any organ but the most common sites are kidney and gallbladder. Xanthogranulomatous appendicitis (XA) is a rare clinical entity. There are a few case reports of XA diagnosed on histopathology but none on cytology. Here we report a case of a 47-year-old lady who presented with acute abdomen and was found to have a mass lesion in the right iliac fossa. She was diagnosed with XA intraoperatively on imprint cytology that was subsequently confirmed on histopathological examination. Due to the rarity of XA itself and the use of imprint cytology for intraoperative diagnosis the case is being presented.

Abdominal manifestations of histiocytic disorders in adults: imaging perspective

Histiocytic disorders (HDs) are a diverse group of diseases characterized by pathologic infiltration of normal tissues by cells of the mononuclear phagocyte system. The spectrum of these diseases ranges from treatable infectious diseases to rapidly progressive, life-threatening conditions. Although they are rare and difficult diagnoses, HDs can be diagnosed with the help of clinical and laboratory analyses, imaging features and tissue biopsy. The clinicopathology and imaging spectrum of select entities belonging to this disorder are presented in this review.

Xanthogranulomatous Appendicitis Mimicking Residual Burkitt's Lymphoma After Chemotherapy

The case of a 23-year-old female treated with aggressive high-dose therapy for Burkitt's lymphoma is reported. A positron emission tomography and computed tomography scan after completion of chemotherapy revealed a residual hypermetabolic lesion in the right pelvic cavity. A pelvic magnetic resonance imaging scan showed circumferential wall thickening at the tip of the appendix. A laparoscopic exploration and appendectomy were performed, and a pathologic examination of the resected appendix revealed xanthogranulomatous appendicitis. This is a rare case of a xanthogranulomatous appendicitis mimicking remnant Burkitt's lymphoma after completion of chemotherapy.

Xanthogranulomatous appendicitis with a fulminant course: report of a case

Xanthogranulomatous inflammation is a well-described entity with involvement of various body organs. But the involvement of vermiform appendix in the disease process is quite rare with only few cases are reported in literature. This case report describes a 50-year-old man, who was diagnosed as a case of acute appendicitis with appendicular lump on the basis of clinical history, physical examination, and hematological and radiological investigations. Patient underwent surgical interventions twice. But, he succumbed to the disease. We are reporting this case in view of rarity of the disease and the fulminant course, which has not been described in any other reports.

Xanthogranulomatous appendicitis in a child: report of a case and review of the literature

Xanthogranulomatous inflammation is a well-described inflammatory process, which may involve any organ but is most frequently encountered in the gall bladder and the kidney. There are rare reports of xanthogranulomatous appendicitis (XA) in the adult population, but only one brief mention of such a diagnosis in a child. In this report, we describe the case of an 11-year-old boy who presented with clinical signs and symptoms of acute appendicitis necessitating appendectomy. Upon microscopic examination, the appendix showed the typical features of XA. To the best of our knowledge, this is the first well-described case XA in a noninterval appendix in a child. We also reviewed the limited medical literature on the subject.

Xanthogranulomatous appendicitis

A 78-years-old man presented with right lower quadrant pain for 2 months. Computed tomography revealed an irregular and multicystic mass near the cecum like as appedeceal mucocle. The lesion was diagnosed xanthogranulomatous appendicitis by histopathological findings of surgical specimen. Xanthogranuloma is uncommon disease, especially in the appendix. We report an interesting case of xanthogranulomatous appendicitis mimicking appendiceal mucocele in radiological images.

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.

Antibiotic Therapy and Interval Appendectomy for Perforated Appendicitis in Children: A Selective Approach

The role of initial nonoperative treatment in pediatric perforated appendicitis remains controversial. We examined our outcomes after using this approach in a selective manner. Children with perforated appendicitis treated during a 28-month period were retrospectively reviewed. Antibiotics and delayed appendectomy were used if there were more than 3 days of symptoms, absence of bowel obstruction, absence of diffuse peritonitis, and an appendiceal mass. Of 221 patients with perforated appendicitis, 32 (14%) were treated with this approach. Average age was 7.4 ± 4.2 years. Twenty-eight patients (88%) were successfully managed and 26 (81%) underwent appendectomy 8.6 ± 4.2 weeks after first presentation. Two patients did not respond completely, and underwent appendectomy during the same admission. Two patients initially responded, but had recurrent symptoms necessitating earlier appendectomy. There were no complications. Average total hospital stay was 7.2 ± 3.0 days. Initial nonoperative treatment is highly successful in selected children who meet specific criteria. Failure is not associated with increased morbidity.

Xanthogranulomatous gastritis with pseudosarcomatous changes

Reported herein is a rare case of xanthogranulomatous inflammation of the gastric wall occurring in a 77-year-old man. Two submucosal lesions presented as rapidly enlarging nodules, and biopsy showed interweaving bundles of spindle cells with numerous atypical cells with marked nuclear pleomorphism. The differential diagnosis from mesenchymal malignancies, particularly from a malignant gastrointestinal stromal tumor, was difficult and immunohistochemical investigations could not improve the diagnostic accuracy of HE histology alone. Thus, an erroneous diagnosis of malignancy was made and a partial gastrectomy was performed. On macroscopic examination of the resected material, spontaneous regression of the lesions was observed and microscopic examination showed characteristic features of xanthogranulomatous inflammation; large numbers of foamy histiocytes including multinucleated giant cells were admixed with chronic inflammatory cells and fibrous reaction. Although the precise pathogenesis could not be elucidated, recognition of this unusual morphological appearance is of importance to avoid an overdiagnosis of malignancy.

Pathology of the appendix in children: an institutional experience and review of the literature

BACKGROUND

The appendix can be affected by a variety of congenital and acquired diseases, but acute appendicitis is the most common pathology found in the pediatric population.

OBJECTIVE

This is a retrospective review of all appendectomies performed during a 2-year period at a major children's hospital with a review of the literature regarding the most common pathologic findings.

MATERIALS AND METHODS

The pathology database was reviewed for appendectomy specimens, and patient medical records were evaluated to determine the age, gender, race and operative diagnosis. All slides were reviewed and the histologic findings were recorded.

RESULTS

A total of 392 appendectomies were performed, including 68 incidental appendectomies and 324 performed for clinical suspicion of acute appendicitis. In 247 of the latter, acute appendicitis was confirmed histologically, and of the remainder 14 were interval appendectomies, 2 had findings suspicious for Crohn disease, 1 confirmed diverticulitis and 60 were histologically negative for appendicitis.

CONCLUSION

Acute appendicitis is the most common pathologic cause of appendectomy, but various other pathologic entities are found in children. Examination of the appendix is warranted even when it appears normal on exploration.

Segmental colitis associated with diverticular disease and other IBD look-alikes

Segmental colitis associated with diverticular disease is an inflammatory disorder that bears close clinical and histopathologic similarities to idiopathic inflammatory bowel disease. Comparison with other inflammatory bowel disease-like disorders, such as blind-ended pouches in ulcerative colitis, chronic granulomatous appendicitis, and delayed-surgery appendicitis, affords intriguing analogies and potential clues to its pathogenesis.

Role of interval appendectomy in the management of complicated appendicitis in children

INTRODUCTION

The aim of this study was to ascertain the optimal treatment for children with complicated appendicitis. We reviewed an inception cohort of children with documented complicated appendicitis to develop criteria for interval appendectomy. We compared the outcomes of two treatments: immediate operation and interval appendectomy.

METHODS

Children with complicated appendicitis were separated into two groups. Group 1 patients had had symptoms of complicated appendicitis for less than 72 hours or appeared toxic. Group 2 patients had had symptoms of complicated appendicitis for longer than 72 hours and did not appear toxic. Group 1 underwent immediate operation treated by criteria previously published. Group 2 patients were treated in hospital with triple antibiotics until they were afebrile, had normal white blood cell counts, tolerated an oral diet, and had adequate pain control. They were discharged on oral metronidazole or metronidazole plus Bactrim for 6 weeks and then underwent interval appendectomy.

RESULTS

A total of 86 children had complicated appendicitis; 59 were operated on immediately, and 27 underwent an interval appendectomy. Complications included one wound infection and two intraabdominal abscesses (all in group 1). There was one death (group 1). The length of stay for the immediate operation group was 4.9 +/- 1.7 days; the initial-admission length of stay for the interval appendectomy group was 4.1 +/- 1.0 days with a subsequent postoperative stay of 0.9 +/- 0.8 days. One patient in the interval appendectomy group was treated off protocol.

CONCLUSIONS

Treating selected children with interval appendectomy led to a decrease in complications and a shorter length of stay in this limited population. Interval appendectomy is a safe, cost-effective, useful adjunct treatment for children with complicated appendicitis.

Xanthogranulomatous inflammation presenting as a submucosal mass of the sigmoid colon

Xanthogranulomatous inflammation (XGI) is a well-recognized disease process in the kidney and gallbladder. However, involvement of the colon is extremely rare. On the other hand, it is important to recognize that clinically and radiologically, XGI could be misinterpreted as an infiltrative cancer. Recently the authors encountered a 38-year-old woman who presented with a submucosal mass-like lesion in the sigmoid colon. Radiological imaging had also suggested a possibility of sigmoid colon cancer as well as pelvic inflammatory disease or actinomycosis. Although XGI may rarely occur in the large bowel, it should be considered in patients with a colonic submucosal mass. In addition, it is important to make an intraoperative pathological diagnosis in order to avoid any excessive operative stress.