Table 1

Causes of appendicitis

PRIMARY CAUSES OF APPENDICITIS
Idiopathic lymphatic hyperplasia
Fecalith obstruction

SECONDARY CAUSES OF APPENDICITIS
Inflammatory
Crohn's disease
Ulcerative Colitis
Sarcoidosis
Granulomatous appendicitis
Infective
Bacterial (Tuberculosis, Typhus, Actinomycosis, E. coli and B. fragilis, Pseudomonas, Yersinia, Eikenella corrodens infections)
Viral (Adenovirus, Cytomegalovirus infections)
Fungal (Aspergillosis, Histoplasmosis)
Parasitic (Enterobius vermicularis, Strongyloides stercoralis, Entamoeba histolytica infections, Ascariasis, Schistosomiasis, Cryptosporidiosis, Taeniasis)
Neoplastic
Primary neoplasm (Adenoma, Mucinous cystadenomas, Cystadeno-carcinomas, Carcinoid tumors, Mesenchymal tumors)
Metastasis from other organs (stomach, lung, femal genital tract)
Lymphoma-leukemia
Endometriosis
Ischemic
Vascular occlusion for thrombosis, vasculitis
Neurogenic
Neural proliferations and/or increased number of endocrine cells
Foreign body obstruction
Small chicken and fish bones, portion of wire, nail, cherry stone, piece of glass, dislocated intrauterine contraceptive device, dislocated biliary stent

Fiume et al. World Journal of Emergency Surgery 2006 1:11   doi:10.1186/1749-7922-1-11