Objective: To report a case of possible severe thrombocytopenia associated with administration of a single dose of plicamycin.
Case summary: A 73-year-old man with prostate cancer was admitted to the hospital with hypercalcemia (total serum calcium concentration 4.02 mmol/L) and a low baseline platelet count (152 x 10(9)/L). Because of his symptomatic hypercalcemia, he was treated with NaCl 0.9%, furosemide, oral inorganic phosphate, and a single dose of plicamycin (15 micrograms/kg). Five days after plicamycin administration his platelet count decreased to 52 x 10(9)/L, and continued to decrease further even after the transfusion of four units of platelets to a nadir of 7 x 10(9)/L (hospital day 20). A second transfusion produced a small increase in his platelet count. The patient's clinical status continued to deteriorate, however, and he subsequently died.
Discussion: Plicamycin and other drugs that may induce thrombocytopenia are reviewed. The time course between plicamycin administration and the development of thrombocytopenia in our patient is assessed. Other contributing factors such as a low baseline platelet count and advanced age are also addressed.
Conclusions: It is likely that the severe thrombocytopenia experienced by our patient was caused by a single dose of plicamycin. Adjusting the dosage for a patient's renal function as well as close monitoring of the platelet count are necessary when administering this drug. We report this case to remind clinicians of the potential for the development of severe thrombocytopenia following administration of a single dose of plicamycin.