Mycobacterium avium subspecies paratuberculosis (Map) is a zoonotic pathogen whose association with Crohn's disease in humans is under scrutiny. To investigate its association with other chronic diseases where the involvement of a persistent pathogen as Map could be the trigger

Forty-six diabetic patients were recruited along with 50 healthy people as control. Map was searched in the PMBC by a specific PCR targeting IS900. Sequence product confirmed identity by sequencing. Also, all the diabetic patients revealed significant humoral immune responses to two recombinant Map antigens and the whole cell lysate of the Map bacilli.

A total of 29 blood samples out of 46 were found to be positive for Map specific PCR (63%) whereas only 8 out of the 50 healthy control samples (16%) generated a positive signal. Extremely significant humoral responses to recombinant HbHA and GSD proteins and the whole cell lysates of the Map bacilli were recorded in T1DM patients as compared to healthy controls.

We report presence of Map DNA and Map specific antibodies in the blood of Type1 Diabetes Mellitus (T1DM) patients in an endemic setting like Sardinia. Finding evidence of Map involvement in T1DM is perhaps a novel finding that might serve as a foundation stone in establishing an infectious aetiology for T1DM.