Rasburicase-induced methemoglobinemia: case report, literature review, and proposed treatment algorithm.

Rasburicase for the treatment of tumor lysis syndrome has been associated with hemolytic anemia and methemoglobinemia, usually in patients with G6PD deficiency. Risks and benefits should be considered prior to use of rasburicase in at-risk patients. Methylene blue will worsen the hemolytic anemia in G6PD deficiency and should be avoided.