Effectiveness and nephrotoxicity of colistin monotherapy vs. colistin-meropenem combination therapy for multidrug-resistant Gram-negative bacterial infections.

A retrospective cohort study evaluated the effectiveness and nephrotoxicity of intravenous colistin monotherapy vs. colistin-meropenem combination therapy for patients with multidrug-resistant Gram-negative bacterial infections. Fourteen patients received intravenous colistin monotherapy and 57 received colistin-meropenem. No significant differences were found concerning clinical response of the infection (12/14 (85.7%) vs. 39/57 (68.4%), p 0.32) and development of nephrotoxicity (0/14 (0%) vs. 4/57 (7%), p 0.58). A favourable association was revealed between survival and treatment with colistin monotherapy compared to colistin-meropenem (0/14 (0%) vs. 21/57 (36.8%) deaths, p 0.007), even after adjusting for the variables for which significant differences were found.