Analysis of thiopurine S-methyltransferase phenotype-genotype in a Tunisian population with Crohn's disease.

This study was conducted to investigate the thiopurine S-methyltransferase TPMT activity distribution and gene mutations in Tunisian population with positive diagnostic for Crohn's disease. TPMT activity was measured in Tunisian population (n = 88) by a high performance liquid chromatography assay. Polymerase chain reaction-based methods were used to determine the frequency of TPMT mutant alleles TPMT*2, TPMT*3A, TPMT*3B and TPMT*3C.

Azathioprine-induced severe cholestatic hepatitis in patient carrying TPMT*3C polymorphism.

Case Description: A 40-year-old man with pemphigus foliaceus developed a jaundice and pruritus three weeks after starting azathioprine 100 mg daily. Laboratory investigations revealed a severe cholestatic hepatitis. Azathioprine-induced hepatitis was suspected.