Abstract
Azathioprine can cause severe myelosuppression. The inherited activity of the enzyme thiopurine methyltransferase has been recently recognised as a major factor in the susceptibility to myelosuppression. Thiopurine methyltransferase deficiency occurs at a frequency of one in 300 and is associated with profound myelosuppression after a short course of azathioprine. Very low thiopurine methyltransferase activity represents the TPMT L/TPMT L genotype, and can be detected before therapy with azathioprine is started. We describe the first documented case of azathioprine-induced severe myelosuppression due to thiopurine methyltransferase deficiency in autoimmune liver disease. The azathioprine dose was low (1 mg/kg) and pancytopenia occurred after 56 days therapy. It would be advisable to measure thiopurine methyltransferase activity before patients with autoimmune hepatitis are exposed to azathioprine.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have