Polymyxin B and doxycycline use in patients with multidrug-resistant Acinetobacter baumannii infections in the intensive care unit

• Published in: The Annals of pharmacotherapy Vol. 40; no. 11; p. 1939
• Main Authors: Holloway, Katherine P, Rouphael, Nadine G, Wells, Jane B, King, Mark D, Blumberg, Henry M
• Format: Journal Article
• Language: English
• Published: United States 01.11.2006
• Subjects: Acinetobacter baumannii - drug effects; Acinetobacter Infections - drug therapy; Acinetobacter Infections - epidemiology; Acinetobacter Infections - mortality; Adolescent; Adult; Aged; Cross Infection - drug therapy; Cross Infection - epidemiology; Cross Infection - mortality; Doxycycline - administration & dosage; Drug Resistance, Multiple, Bacterial; Drug Therapy, Combination; Female; Humans; Intensive Care Units - statistics & numerical data; Male; Middle Aged; Polymyxin B - administration & dosage; Polymyxin B - adverse effects; Retrospective Studies
• ISSN: 1542-6270
• DOI: 10.1345/aph.1H353

Multidrug-resistant Acinetobacter baumannii (MDR-Ab) has emerged as an increasingly problematic cause of hospital-acquired infections in the intensive care unit (ICU). MDR-Ab is resistant to most standard antimicrobials but often retains susceptibility to polymyxin B and doxycycline. To evaluate the efficacy and toxicity of polymyxin B and doxycycline in the treatment of MDR-Ab infections. A retrospective chart review was conducted between March 2002 and May 2005 in patients who received doxycycline or polymyxin B for treatment of MDR-Ab infections in ICUs within Grady Memorial Hospital, Atlanta, GA. Thirty-seven patients with MDR-Ab infections were treated with polymyxin B or doxycycline. Median age was 41 years and median ICU length of stay was 18 days prior to acquisition of MDR-Ab. Clinical cure was observed in 22 of 29 (76%) evaluable patients treated with polymyxin B and 2 of 4 (50%) patients treated with doxycycline. In patients with follow-up cultures, microbiological cure was observed in 17 of 21 (81%) patients treated with polymyxin B and 2 of 3 (67%) patients treated with doxycycline. Nephrotoxicity developed in 21% (7 of 33) of patients who received polymyxin B. Neurotoxicity was observed in 2 (6%) patients who received polymyxin B. No adverse reactions were observed with doxycycline. Overall, crude mortality was 27% (9 of 33) and 75% (3 of 4) among those who received polymyxin B and doxycycline, respectively. Three (9%) deaths were attributed to polymyxin B treatment failure, and no deaths were attributed to doxycycline treatment failure. Polymyxin B was effectively used to treat a substantial proportion of critically ill patients with MDR-Ab infection and was associated with a similar rate of nephrotoxicity as previously reported. Doxycycline monotherapy was used in a limited number of patients for the treatment of MDR-Ab; further evaluation of its efficacy in larger numbers of patients is warranted.