Lymphocytotoxic antibodies in patients with inflammatory bowel disease and their spouses--evidence for a transmissible agent.

Serum lymphocytotoxic antibodies (LCA) were detected in twenty-seven out of fifty-three (51%) patients with inflammatory bowel disease (IBD) and in twenty-three out of their fifty-three (43%) unaffected spouses. The prevalence of LCA in both groups was significantly increased (P less than 0.001) compared to that in age- and sex-matched controls (11%) or in control spouses (6%). Concordant expression of LCA occurred in sixteen out of the fifty-three (30%) patient-spouse pairs compared to only one out of the fifty-three (2%) control-spouse pairs (P less than 0.001). In contrast to the LCA results, heterophile antibody titres were similarly distributed in all four study groups. It is suggested that LCA may represent markers of infectious agents in IBD and that their occurrence in unaffected close contacts of patients may indicate transmission of such agents to these subjects.