Mesalazine (5-aminosalicylic acid) induced chronic hepatitis

Background-Treatment of ulcerative colitis or Crohn's disease with sulphasa lazine causes several adverse effects, including hepatitis. Sulphasalazine is cleaved by colonic bacteria into 5-aminosalicylic acid and sulphapyridin e. Received wisdom was that 5-aminosalicylic acid was topically active, whe reas sulphapyridine was absorbed and caused immunoallergic side effects. Me salazine, a slow release formulation of 5-aminosalicylic acid, was expected to be a safe alternative. However, several cases of acute hepatitis have b een reported. Case report-A 65 year old man had increased liver enzymes, anti-nuclear and anti-smooth muscle autoantibodies and IgG levels, and lesions of chronic h epatitis after 21 months of mesalazine treatment. Although liver dysfunctio n had been identified eight months earlier, simvastatin rather than mesalaz ine had been withdrawn, without any improvement. In contrast, liver enzyme and IgG levels became normal and autoantibodies disappeared after discontin uation of mesalazine administration. Conclusion-Contrary to initial expectations, mesalazine can cause most of t he sulphasalazine induced adverse effects, and hepatic side effects may be almost as frequent. When liver dysfunction occurs, mesalazine administratio n should be discontinued to avoid the development of chronic hepatitis and liver fibrosis.