allopurinol and Neuromuscular-Diseases

We report a 44 year old man who developed external ophthalmoplegia and predominantly respiratory, truncal and bulbar weakness with brisk reflexes, histological evidence of an inflammatory myopathy and a high titre of acetylcholine receptor antibodies, one month after starting hydroxyurea and allopurinol for chronic myeloid leukaemia. The temporal relationship suggests a possible association between this patient's unusual neuromuscular disorder and either the chronic myeloid leukaemia or its treatment.

Topics: Adult; Allopurinol; Antineoplastic Combined Chemotherapy Protocols; Humans; Hydroxyurea; Leukemia, Myelogenous, Chronic, BCR-ABL Positive; Male; Myositis; Neuromuscular Diseases; Ophthalmoplegia

Azathioprine toxicity was examined in 64 consecutively treated patients with various neuromuscular diseases. Reversible leukopenia was seen in 14 patients (22%). Hepatotoxicity developed in six patients (9%), and a systemic reaction characterized by fever, abdominal pain, nausea, vomiting, and anorexia occurred in eight patients (12%). Toxic effects limited the dose of azathioprine in 27 patients (42%) and led to discontinuation of therapy in 13 (20%). Macrocytosis developed in 20% of patients, but did not require an adjustment in the dose. Two patients received allopurinol and azathioprine; both developed reversible leukopenia and macrocytosis. Patients with hematologic and hepatic toxicity, but not those with systemic toxicity, successfully tolerated retreatment with azathioprine. Toxicity was delayed as long as 56 weeks after starting azathioprine in some patients.

Topics: Allopurinol; Azathioprine; Drug Therapy, Combination; Female; Hematologic Diseases; Humans; Leukopenia; Liver; Male; Neuromuscular Diseases; Time Factors