[Hypercalcemia associated with all-trans retinoic acid therapy for microgranular type acute promyelocytic leukemia].

A 24-year-old man was admitted to the hospital for pancytopenia. Peripheral blood test and bone marrow aspiration demonstrated an increase in hypogranular promyelocytes. Karyotype analysis and RT-PCR showed 47, XY, t(15;17)(q22;q12), +12, and PML-RARA, respectively. The patient was diagnosed as having acute promyelocytic leukemia microgranular type (M3v) and was therefore administered all-trans retinoic acid (ATRA). Idarubicin and Ara-C were later added to the treatment regimen because of an increased number of leukemic cells. Nausea, vomiting and general fatigue associated with hypercalcemia developed on day 30. There were no findings indicating infection. The administration of ATRA was thus suspected to have induced hypercalcemia. ATRA was therefore discontinued and prednisolone and elcatonin were administered instead. Five days after this change, the serum calcium level normalized. Complete remission was thereafter confirmed on day 45. Hypercalcemia associated with ATRA therapy for APL is rare, and to date, there have been no case reports describing hypercalcemia associated with M3v in the literature. Interaction of fosfluconazole was suspected of causing hypercalcemia when used concomitantly with ATRA.