Leukemic relapse presenting as sciatic nerve involvement by chloroma (granulocytic sarcoma).

A relapse of acute nonlymphocytic leukemia in a child presented as subacute mononeuropathy involving the sciatic nerve. Surgical exploration showed a chloroma (granulocytic sarcoma) of the distal sciatic nerve, but resection and irradiation did not lead to recovery of nerve function or complete resolution of the patient's symptomatic neuropathic pain. This case represents a rare neurologic complication of what is currently an uncommon presentation for leukemic relapse, and may be the only reported case of chloromatous involvement of the peripheral nervous system (PNS) without coexisting epidural or leptomeningeal leukemia.