Thiopurines ulcerative colitis

Corominas, H., Domenech, M., Gonzalez, D., et al. (2000) Allelic variants of the thiopurine S-methyltransferase deficiency in patients with ulcerative colitis and in healthy controls. Am. J. Gastroenterol. 95, 2313-2317. 

Azathioprine and 6-MP are important agents in the induction and maintenance of remission of ulcerative colitis and Crohn s disease. Although the optimal dose is uncertain, most patients with normal thiopurine-S-methyltransferase (TPMT) activity (see below) are treated with 6-MP, 1-1.5 mg/kg/d, or azathioprine, 2-2.5 mg/kg/d. After 3-6 months of treatment, 50-60% of patients with active disease achieve remission. These agents help maintain remission in up to 80% of patients. Among patients who depend on long-term glucocorticoid therapy to control active disease, purine analogs allow dose reduction or elimination of steroids in the majority. 

Pancreas In a retrospective, multicenter study in 241 patients with inflammatory bowel disease and 108 patients with vasculitis the cumulative incidence of thiopurine-induced acute pancreatitis in Crohn s disease equalled that in ulcerative colitis and vascuhtis (2.6%, 3.7%, and 1.9% respectively) [165 ]. 

Of 135patients with Crohn s disease (n — 88) or ulcerative colitis (n = 47), 65 stopped taking it because of adverse events after 25 (8-92) days the other 70 patients tolerated mercaptopurine and were followed up for 736 (362-1080) days [109 ]. Mercaptopurine was tolerated in 12 of 17 patients with hepatotoxicity and in 13 of 19 with arthral-gia/myalgia during azathioprine treatment. Previous abdominal surgery was more common in those who had adverse reactions to mercaptopurine (39/65 vs. 27/70), and thiopurine methyltransferase activity was higher in those who were tolerant of mercaptopurine. 

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