Aim: The purpose of our study was to examine measles IgM immunoreactivity in patients with inflammatory bowel disease.
Patients and methods: In an International collaborative study, serum measles IgM immunoreactivity was assayed in consecutive outpatients with Crohn's disease (n = 95), ulcerative colitis (n = 79), viral hepatitis (n = 63) and blood donors (n = 30). Two commercial measles assays--enzyme linked immunosorbent assay and indirect fluorescence assay--and a Public Health Laboratory Service (PHLS) "in house" antibody capture radioimmunoassay were used. Results were compared with serum rubella and Epstein-Barr virus-specific IgM immunoreactivity, total serum IgM, and measles IgG immunoreactivity. Twenty patients with inflammatory bowel disease were studied serially over a 4-month period.
Results: By enzyme linked immunosorbent assay, the prevalence of raised serum measles IgM immunoreactivity was significantly greater in patients with Crohn's disease 23/95 (24%) and ulcerative colitis 20/79 (27%) compared with hepatitis patients 2/63 (3%) and normal controls 0/30 (0%) (p < 0.001). Indirect fluorescence assay produced significantly more positive results than enzyme linked immunosorbent assay in both Crohn's disease (50/87; 57%) and ulcerative colitis (35/68; 51%) but not in controls (0%) (p < 0.001). In contrast, no sera were positive using MCRIA. In the enzyme linked immunosorbent assay, measles IgM immunoreactivity did not correlate with either total IgM, rubella or Epstein-Barr virus IgM immunoreactivities-which were not raised-measles IgM immunoreactivity, or disease activity. Patients not receiving steroids were more likely to have raised measles IgM immunoreactivity (p < 0.5). All sera tested for Rheumatoid factor were negative. Of 20 patients with inflammatory bowel disease studied by ELISA over a 4-month period, 50% showed raised measles IgM immunoreactivity at some stage.
Conclusion: The data suggest a specific and fluctuating immune response to measles virus in patients with Crohn's disease and ulcerative colitis, that may be modified by corticosteroid therapy.