DISEASE ksums肉芽肿性疾病ppt课件.pptx

GRANULOMATOUS DISEASEEmad Raddaoui,MDFCAP, FASCGRANULOMATOUS DISEASEGranulomatous inflammation is a distinctive pattern of chronic inflammatory reaction characterized by focal accumulations of activated macrophages, which often develop an epithelial-like (epithelioid) appearance. GRANULOMATOUS DISEASEIt is encountered in a limited number of immunologically mediated, infectious and some non-infectious conditions. Its genesis is firmly linked to immune reactions. GRANULOMATOUS DISEASEExamples include:tuberculosis, sarcoidosis, cat-scratch diseaseLmphogranuloma inguinale, leprosy, brucellosis, syphilis, some mycotic infections, berylliosis, and reactions of irritant lipids are also included. GRANULOMATOUS DISEASERecognition of the granulomatous pattern in a biopsy specimen is important because of the limited number of possible conditions that cause it and the significance of the diagnoses associated with the lesions. Examples of GranulomasInfectious granulomas:TuberculosisBrucellosisLymphogranuloma venereumCat- scratch diseaseFungal infectionSyphilisParasitic infection eg. Schistosomiasis. Examples of GranulomasForeign-body granulomas are typically non necrotic and form in the presence of the following:Particulate matter(e.g., glass, soil, gravel, metal).Synthetic material (e.g., surgical sutures).Vegetable matter (e.g., cellulose, which may occur due to fecal contamination of tissues in the presence of a fstula or perforated bowel)Examples of GranulomasUnknown causes: Sarcoidosis is caused by epithelioid granulomas and may involve lungs, liver, spleen, lymph nodes and skin. The granulomas are non-necrotic, uniformly sized and multiple.DiseaseCauseTissue ReactionTuberculosisMycobacterium tuberculosisNoncaseating tubercle (granuloma prototype): a focus of epithelioid cells, rimmed by fibroblasts, lymphocytes, histiocytes, occasional Langhans giant cell; caseating tubercle: central amorphous granular debris, loss of all cellular detail; acid-fast bacilliLeprosyMycobacter