Clinical Efficacy of Polymyxin B in Patients Infected with Carbapenem-Resistant Organisms

Qiong Lu,1,* Guo-Hua Li,1,* Qiang Qu,2 Hai-Hong Zhu,1 Yue Luo,3 Han Yan,1 Hai-Yan Yuan,1 Jian Qu1 1Department of Pharmacy, the Second Xiangya Hospital, Central South University; Institute of Clinical Pharmacy, Central South University, Changsha, People’s Republic of China; 2Department of Pharmacy, Xiangya Hospital, Central South University, Changsha, People’s Republic of China; 3Department of Pharmacy, the People’s Hospital of LIUYANG, Liuyang, People’s Republic of China*These authors contributed equally to this workCorrespondence: Jian QuDepartment of Pharmacy, the Second Xiangya Hospital, Central South University; Institute of Clinical Pharmacy, Central South University, No. 139 Middle Renmin Road, Changsha, People’s Republic of ChinaTel +86-15973190614Fax +86-0731-85292072Email qujianstanley@csu.edu.cnPurpose: Carbapenem-resistant organisms (CROs) pose great challenges for clinical treatment. Polymyxin B (PMB) is one of the “last resort” choices of CRO infections. We explored the possible factors affecting PMB efficacy.Patients and Methods: This retrospective study involved CRO-infected patients treated with PMB for ≥ 72 h. The endpoint indicator was clinical efficacy. We compared the characteristics (demographics, pathogenic bacteria, PMB treatment) between patients who had “clinical success” (CS) and “clinical failure” (CF).Results: A total of 191 patients were enrolled: 110 in the CS group and 81 in the CF group. The total cumulative dose for the CS group was higher than the CF group [1100 (700– 1443.75) vs 800 (500– 1112.5) mg; P = 0.001]. Treatment duration in the CS group was longer than the CF group [11 (8– 14) vs 8 (6– 11) days; P < 0.000]. Multivariate logistic regression analysis showed mechanical ventilation, vasoactive agents, multiple-site infection, and total cumulative dose to be independently associated with clinical efficacy. Cox survival analysis for 30-day mortality also showed that the use of vasoactive agents and the total cumulative dose of PMB could influence survival time and mortality rate independently.Conclusion: PMB had good efficacy and a low prevalence of adverse reactions. The total cumulative dose, duration of PMB treatment, mechanical ventilation, vasoactive agents, and multiple-site infection were factors associated with the clinical efficacy of PMB.Keywords: polymyxin B, carbapenem-resistant organisms, clinical efficacy, adverse effect, cumulative dose