Efficacy and safety of polymyxin B in carbapenem-resistant gram-negative organisms infections

OBJECTIVE: To investigate how to use polymyxin B rationally in order to produce the best efficacy and safety in patients with carbapenem-resistant gram-negative organisms (CRO) infection. METHODS: The clinical characteristics and microbiological results of 181 patients caused by CRO infection treated with polymyxin B in the First Affiliated Hospital from July 2018 to May 2020 were retrospectively analyzed. The bacterial clearance rate, clinical efficacy, adverse drug reactions and 28 days mortality were evaluated. RESULTS: The overall effective rate of 181 patients was 49.72%, the total bacterial clearance rate was 42.0%, and the 28 day all-cause mortality rate was 59.1%. The effective rate and bacterial clearance rate in the group of less than 24 h from the isolation of CRO to the use of polymyxin B were significantly higher than those in the group of more than 24 h. Logistics multivariate regression analysis showed that the predictive factors for effective treatment of CRO with polymyxin B were APACHEII score, duration of polymyxin B treatment, combination of polymyxin B and other antibiotics, and bacterial clearance. 17 cases (9.36%) of acute kidney injury were considered as polymyxin B nephrotoxicity and 4 cases (23.5%) recovered after polymyxin B withdrawal. After 14 days of polymyxin B use, 3 cases of polymyxin B resistance appeared, and there were 2 cases of polymyxin B resistance in the daily dose 1.5 mg/kg/day group. CONCLUSION: For CRO infection, the treatment of polymyxin B should be early, combined, optimal dose and duration of treatment, which can achieve better clinical efficacy and microbial reactions, and reduce the adverse reactions and drug resistance.