Topical chloramphenicol and the risk of acute leukaemia in adults

Abstract

To investigate the possible role of topical chloramphenicol in the development of adult acute leukaemia. The design of the study was a population-based age- and sex-matched case-control study, which collected cases of adult acute leukaemia between 1991 and 1996. Caucasian cases (807) and 1593 Caucasian controls were interviewed in person using a highly structured questionnaire. General practitioner medical records were abstracted for previous topical chloramphenicol use. 797 cases and 1570 controls were included in the analysis. No association was observed for topical chloramphenicol use and acute leukaemia (adjusted odds ratio, 1-year lag period (OR) 0.91 95% confidence interval (CI) 0.70-1.17). Similar results were observed when the analysis was repeated by diagnostic subgroup and sex. For all the data, a small, non-significant increased risk was observed (OR=1.21, 95% CI 0.65-2.25) if chloramphenicol had been prescribed three, or more times, but there was no statistically significant dose-response relationship (chi(2)=1.40, two-sided p=0.24). The results, based on a robust study design, show no evidence of an increased risk of developing adult acute leukaemia after topical chloramphenicol use. Copyright (c) 2000 John Wiley & Sons, Ltd.