This article is from Medscape's GI page.M. avium Implicated in Crohn's Disease, Perhaps Also Irritable Bowel SyndromeBy Richard WoodmanLONDON (Reuters Health) Aug 06 - Researchers said on Wednesday they had found a "highly significant" link between Crohn's disease and a mycobacterium that can be passed to humans in milk.Professor John Hermon-Taylor and his research team at St. George's Hospital Medical School in London said they had detected Mycobacterium avium paratuberculosis (MAP) bacteria in 92% of ileocolonic biopsy specimens from patients with Crohn's disease but in only 26% of patients in a control group."The rate of detection of MAP in individuals with Crohn's disease is highly significant and implicates this pathogen in disease causation," they write in the July issue of the Journal of Clinical Microbiology."The problems caused by the MAP bug are a public health tragedy", said Dr. Hermon-Taylor, who has sent a copy of the paper to Britain's Chief Medical Officer, Liam Donaldson.The study was backed by the medical charity Action Research, which said previous findings showed live MAP bacteria is present in 2% of retail pasteurised milk cartons."The discovery that the MAP bug is present in the vast majority of Crohn's sufferers means it is almost certainly causing the intestinal inflammation," the charity said in a statement.It added: "Action Research does not recommend that anyone stops drinking milk. However, for those individuals with Crohn's disease or their close relatives, who may feel particularly at risk, it may be sensible to start drinking UHT milk. As UHT involves higher pasteurisation temperatures, it is probable that MAP is destroyed."The charity called for Crohn's disease to be made a reportable condition, for more stringent milk pasteurisation, for tests for MAP in dairy herds, and procedures for reducing MAP infection on farms.Hermon-Taylor said an unexpected finding of the research showed that patients with irritable bowel syndrome (IBS) were also infected with the MAP bug."In animals, MAP inflames the nerves of the gut," he said. "Recent work from Sweden shows that people with IBS also have inflamed gut nerves. There is a real chance that the MAP bug may be inflaming people's gut nerves and causing IBS."J Clin Microbiol 2003;41:2915-2923.