Mycobacterium avium subsp. paratuberculosis and Crohn's disease: characterization of the interaction with different aspects of the disease.

Crohn's disease (CD) is a chronic granulomatous inflammatory bowel disease with no fully understood etiology and cure. Mycobacterium avium subspecies paratuberculosis (MAP), the etiologic agent of paratuberculosis, is also isolated from samples from human patients with CD. Paratuberculosis is characterized by persistent diarrhea and progressive weight loss and primarily affects ruminants, which eliminate the agent via feces and milk. The involvement of MAP in the pathogenesis of CD and other intestinal diseases is unclear. Thus, the present study aimed to analyze immunological, socioepidemiological, biochemical, and therapeutic variables that may be related to the occurrence of MAP in blood samples and CD patients. The sampling was random, and the population of origin was the patients from the Bowel Outpatient Clinic of the Alpha Institute of Gastroenterology (IAG), Hospital das Clínicas, Universidade Federal de Minas Gerais (HC-UFMG). Blood samples were collected from 20 patients with CD, eight with ulcerative rectocolitis (UCR), and 10 control patients without inflammatory bowel diseases. Samples were subjected to real-time PCR for detection of MAP DNA, oxidative stress analyses, and socioepidemiological variables. MAP was detected in 10 (26.3%) of the patients, seven (70%) were CD patients, 2 (20%) were URC patients, and one (10%) was a non-IBD patient. MAP was found more frequently among CD patients, but not restricted to CD patients. The presence of MAP in the blood of these patients occurred simultaneously with an inflammatory response with an increase in neutrophils and significant alterations in the production of antioxidant enzymes such as catalase and GST.