DRUG-INDUCED THROMBOCYTOPENIA - CLINICAL-DATA ON 309 CASES AND THE EFFECT OF CORTICOSTEROID-THERAPY

Objective: To analyse the clinical picture and the course of thrombocy topenia induced by non-cytotoxic drugs, and to evaluate a possible the rapeutic effect of corticosteroids. Methods: A retrospective analysis of 309 well-documented cases of drug-induced thrombocytopenia was perf ormed. Data sources were reports from the files of the Danish Committe e on Adverse Drug Reactions and discharge summaries. Results: The medi an length of exposure to the offending drug, before development of thr ombocytopenia, was 21 days. The median nadir platelet count was 11 x 1 0(9).1(-1) and 74% of the patients had clinical haemorrhage. Bone marr ow examination generally showed hyperplastic reactive changes and a va riable number of megakaryocytes. Slight leucopenia was present in 6% o f the patients and 16% were anaemic. Complete recovery was seen in 87% of cases, with a median recovery rate of 8 days. The standard treatme nt was corticosteroids, which were administered in 53% of the cases. N o difference in recovery between corticosteroid-treated and untreated patients was observed. No other clinical parameter affected the recove ry rate. The mortality rate due to haemorrhage was 3.6%. Conclusion: T hrombocytopenia induced by non-cytotoxic drugs is characterised by a h eterogeneous clinical picture and recovery is generally rapid. Althoug h corticosteroids seem inefficient, we still recommend that severe sym ptomatic cases of drug-induced thrombocytopenia are treated as idiopat hic thrombocytopenic purpura due to the difficult initial differentiat ion between the two conditions.