A possible role for bacteria in the pathogenesis of insulin dependent diabetes mellitus

The hypothesis proposed is that insulin dependent diabetes mellitus (IDDM) is caused by an autoimmune response precipitated by common bacteria which have antigens in common with pancreatic beta cells. If the bacteria are enteric, but IDDM arises when first exposure occurs in the nasopharynx following a viral respiratory tract infection, then the various epidemiological features of IDDM can be explained. These include a latent interval between disease onset and clinical presentation, seasonal variation in presentation, an increased incidence in temperature climates and technologically advanced countries, and the lack of an effect of incidence on age distribution. The hypothesis points to new avenues of research and should be pursued.