Granulomatous disease in the vermiform appendix.

Area of Science:

• Gastroenterology
• Pathology
• Surgical Pathology

Background:

• Crohn's disease (CD) is a chronic inflammatory bowel disease.
• Appendiceal involvement in CD is uncommon, with primary appendiceal CD being even rarer.
• Histopathological diagnosis of CD in appendectomy specimens is crucial for understanding disease patterns.

Purpose of the Study:

• To review the histopathological features of primary Crohn's disease of the appendix.
• To evaluate the clinical outcomes of patients diagnosed with primary appendiceal Crohn's disease.
• To discuss the differential diagnosis of granulomatous appendiceal lesions.

Main Methods:

• Retrospective review of 19 appendectomy specimens diagnosed with primary Crohn's disease over a 20-year period.
• Analysis of histopathological findings, including inflammation, fibrosis, and granulomata.
• Correlation of histopathological findings with subsequent clinical follow-up and outcomes.

Main Results:

• Primary Crohn's disease of the appendix represented 4.9% of all CD diagnoses in the study period.
• Predominant histopathological features included transmural inflammation, fibrosis, and epithelioid granulomata with giant cells.
• One patient (5.3%) developed subsequent ileal and cecal disease, and another (5.3%) developed perianal fistulae, indicating potential for future disease progression.

Conclusions:

• Primary Crohn's disease of the appendix is typically an isolated finding.
• Rarely, appendiceal Crohn's disease may precede or indicate more extensive gastrointestinal involvement.
• Accurate histopathological assessment is vital for diagnosing appendiceal Crohn's disease and predicting patient prognosis.