Abstract

Speculation that M. avium subsp. paratuberculosis (MAP), the infectious agent of Johne`s disease, might be involved in the aetiology of Crohn’s Disease (CD) in humans was first voiced in 1913. No supportive evidence was obtained until the organism was identified in cultures from a small number of CD cases in the 1980`s. Evidence accumulated over the last 15 to 20 years has left the medical community somewhat polarised about the possible role of MAP in Crohn`s disease. Technological advances enabling more sensitive detection of bacteria or their components (e.g. PCR, immunohistochemistry), or immunological responses to them, have not clarified the fundamental question of whether an apparent association between the presence of MAP and CD lesions may have any causal significance. The basis for concluding that MAP has a causal role in the aetiology of CD is unconvincing.

PR, Davies

Proceedings of the New Zealand Society of Animal Production, Volume 62, Palmerston North, 290-293, 2002