DNA VIRUSES IN THE PATHOGENESIS OF SPORADIC CHRONIC IDIOPATHIC INTESTINAL PSEUDOOBSTRUCTION

Background - Hereditary forms of chronic idiopathic intestinal pseudo- obstruction (CIIP) are well described but the aetiology of most cases of sporadic CIIP is unknown. Aim - To determine whether herpes viruses can persist in the gastrointestinal tract, thereby implicating them i n the pathogenesis of CIIP. Methods - Twenty one specimens of small an d large intestine from 13 patients with CIIP (eight visceral myopathy, three visceral neuropathy, two undifferentiated), and 12 patients ope rated on for colorectal cancer (controls) were examined for evidence o f Herpesvirus DNA (cytomegalovirus, Epstein-Barr virus (EBV), herpes s implex virus type 1, and varicella tester virus) by nested polymerase chain reaction (PCR) and in situ DNA hybridisation (ISH) to localise s ignal to the muscularis propria or myenteric plexus. Results - Screeni ng with nested PCR produced three patients with positive results. One patient with an inflammatory visceral neuropathy had EBV detected in t he small intestine by PCR, and ISH demonstrated localisation to neuron es in the myenteric plexus. A patient with a visceral myopathy had EBV DNA in both the small and large intestine; and one patient with a vis ceral neuropathy had small intestine positive for CMV DNA (both negati ve by ISH). No control tissue was positive for any virus. Conclusions - In individual patients there appears to be evidence linking a viral aetiology to sporadic CIIP. The role of neurotropic viruses in acute a nd chronic motility disturbances needs further study.