Rare case of tacrolimus-induced immune hemolytic anemia in a child after liver transplantation.

Tacrolimus (FK506), a macrolide antibiotic derived from actinomycete fermentation products, has emerged as the primary clinical anti-rejection drug. Previous studies have shown that patients frequently encounter adverse effects, such as infections, hypertension, diabetes mellitus, hepatic impairment, and renal impairment. However, few occurrences of immune hemolytic anemia caused by tacrolimus have been reported. We present a patient with drug-induced immune hemolytic anemia caused by oral tacrolimus after liver transplantation. The patient's direct antiglobulin test is strongly positive(IgG type), with both serum antibody screening and red blood cell eluate antibody screening positive. Furthermore, the crossmatches in the anti-human globulin gel are incompatible. The manual polybrene method employed in the antibody screening and crossmatching tests eliminates interference from tacrolimus.