Mycobacterium avium paratuberculosis in Italy: commensal or emerging human pathogen?

Specific bacterial infections or alterations of the gut microbiota likely trigger immuno-pathological phenomena associated with Crohn's disease and ulcerative colitis. Mycobacterium avium subspecies paratuberculosis is a candidate etiological agent of Crohn's disease. Definitive causal connection between Mycobacterium avium subspecies paratuberculosis infection and Crohn's disease has not been demonstrated.