Clinical response and outcome of pneumonia due to multi-drug resistant Acinetobacter baumannii in critically ill patients

  • Lida Shojaei Department of Clinical Pharmacy, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran
  • Mostafa Mohammadi Department of Intensive Care Unit, Imam Khomeini Hospital, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
  • Mohammad-Taghi Beigmohammadi Department of Intensive Care Unit, Imam Khomeini Hospital, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
  • Mahsa Doomanlou Central Laboratory, Imam Hospital Complex, Tehran University of Medical Sciences, Tehran, Iran
  • Alireza Abdollahi Department of Pathology, School of Medicine, Tehran University of Medical Sciences, Imam Khomeini Hospital, Tehran, Iran
  • Mohammad-Mehdi Feizabadi Department of Medical Microbiology, Tehran University of Medical Sciences, Tehran, Iran Thoracic Research Center, Imam Khomeini Hospital, Tehran University of Medical Sciences, Tehran, Iran
  • Hossein Khalili Department of Clinical Pharmacy, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran
Keywords: Acinetobacter baumanii, pneumonia, Antibiotic therapy, Clinical response


Background and Objectives: The frequency of multi-drug resistant Acinetobacter spp. infections is increasing in Iran. Considering availability of limited therapeutic options, clinical response and outcome of ventilator-associated pneumonia due to multi-drug resistant A.baumannii were evaluated in critically ill patients.Materials and Methods: In this prospective study, 29 patients with carbapenem resistance A. baumannii ventilator-associated pneumonia were enrolled. Endotracheal aspirate specimens were analyzed according to the clinical and laboratory standard institute instructions in the hospital’s microbiology laboratory. Demographics, clinical, microbiological and laboratory findings were collected for each patient during the treatment course. Therapeutic empirical regimen, change in antibiotic regimen following receiving antibiogram results, clinical and microbiological responses, duration of ICU stay and outcome were collected for each recruited individual.Results: All of A. baumanii isolates were resistant to pipracillin-tazobactam, ceftriaxon, amikacin and ciprofloxacin. The resistance rate of A. baumanii species was 41.4% for ampicillin/sulbactabm and 93.1% for meropenem. Patients received either meropenem/colistin (51.7%) or meropenem/ampicillin-sulbactam (48.3%) as the treatment regimens based on the antimicrobial susceptibility patterns of isolates. Ventilator-associated pneumonia clinical response, improvement and failure achieved in 15 (51.7%), 8 (27.6%) and 6 (20.7%) of the patients respectively. Microbiological eradication and intermediate status were observed in 9/29 (31%) and 11/29 (37.9%) of patients, respectivelyConclusion: The antibiotic regimens showed comparable efficacy in treatment of VAP due to MDR A. baumannii but mortality rate was high. Considering widespread and high mortality rates associated with MDR infections, applying infection control and antibiotic stewardship programs in hospitals are essential. 


Kara I, Yildirim F, Bilaloglu B, Karamanlioglu D, Kay- acan E, Dizbay M, et al. Comparison of the efficacy of colistin monotherapy and colistin combination ther- apies in the treatment of nosocomial pneumonia and ventilator-associated pneumonia caused by Acineto- bacter baumannii. SAJCC 2015;31:51-58.

Magiorakos AP, Srinivasan A, Carey R, Carmeli Y, Falagas M, Giske C, et al. Multidrug-resistant, extensively drug-resistant and pandrug-resistant bacteria: an international expert proposal for interim standard defi- nitions for acquired resistance. Clin Microbiol Infect 2012; 18:268-281.

Kalil AC, Metersky ML, Klompas M, Muscedere J, Sweeney DA, Palmer LB, et al. Management of Adults With Hospital-acquired and Ventilator-asso- ciated Pneumonia: 2016 Clinical Practice Guidelines by the Infectious Diseases Society of America and the American Thoracic Society. Clin Infect Dis 2016 Sep 1;63(5):575-582.

Teng S-O, Yen M-Y, Ou T-Y, Chen F-L, Yu F-L, Lee W-S. Comparison of pneumonia-and non-pneumo- nia-related Acinetobacter baumannii bacteremia: Im- pact on empiric therapy and antibiotic resistance. J Mi- crobiol Immunol Infect 2015 Oct;48(5):525-530.

Centres for Disease Control and Prevention, US De- partment of Health and Human Services (2016). HAI Data and Statistics. 2016. Available at: hai/surveillance; Accessed October 3, 2016.

Centres for Disease Control and Prevention, US Depart- ment of Health and Human Services (2013), Antibiotic resistance threats in the United States, 2013: Available at: Ac- cessed October 3, 2016.

Go E, Urban C, Burns J, Mariano N, Mosinka-Snipas K, Rahal J, et al. Clinical and molecular epidemiology of Acinetobacter infections sensitive only to polymyxin B and sulbactam. Lancet 1994 Nov 12;344(8933):1329-1332.

Pan T, Liu X, Xiang S, Ji W. Treatment for patients with multidrug resistant Acinetobacter baumannii pulmo- nary infection. Exp Ther Med 2016; 11:1345-1347.

Hsueh P-R, Teng L-J, Chen C-Y, Chen W-H, Yu C-J, Ho S-W, et al. Pandrug-resistant Acinetobacter bau- mannii causing nosocomial infections in a university hospital, Taiwan. Emerg Infect Dis 2002; 8:827-832.

Sharma P, Bashir YU, Kaur S, Kaur P, Aggarwa A.Emerging antimicrobial resistance and clinical rele- vance of Acinetobacter isolates in a tertiary care hos- pital of rural area of Punjab, India. J Microbiol Antimi- crob 015;1(1):8-12.

Reis AO, Luz DA, Tognim MC, Sader HS, Gales AC.Polymyxin-resistant Acinetobacter spp. isolates: what is next?-Letters-Letter to the Editor. Emerg Infect Dis 2003; 9: 1025–1027.

Craven DE, Hudcova J, Rashid J. Antibiotic therapy for ventilator-associated tracheobronchitis: a standard of care to reduce pneumonia, morbidity and costs? Curr Opin Pulm Med 2015; 21:250-259.

Vourli S, Frantzeskaki F, Meletiadis J, Stournara L, Armaganidis A, Zerva L, Dimopoulos G. Synergistic interactions between colistin and meropenem against extensively drug-resistant and pandrug-resistant Acinetobacter baumannii isolated from ICU patients. Letters to the Editor. Int J Antimicrob Agents 2015; Jun;45(6):670-671.

Özvatan T, Akalın H, Sınırtaş M, Ocakoğlu G, Yılmaz E, Heper Y, Kelebek N, İşçimen R, Kahveci F. Noso- comial Acinetobacter pneumonia: Treatment and prog- nostic factors in 356 cases. Respirology 2016; 21:363-369.

Moradi J, Hashemi FB, Bahador A. Antibiotic resis- tance of Acinetobacter baumannii in Iran: a systemic review of the published literature. Osong Public Health Res Perspect 2015; 6:79-86.

Florescu DF, Qiu F, McCartan MA, Mindru C, Fey PD, Kalil A. What is the efficacy and safety of colistin for the treatment of ventilator-associated pneumonia? A systematic review and meta-regression. Clin Infect Dis 2012;54:670-680.

Tablan OC, Anderson LJ, Besser R, Bridges C, Hajj- eh R; CDC.; Healthcare Infection Control Practic- es Advisory Committee. Guidelines for preventing health-care-associated pneumonia, 2003: recommen- dations of CDC and the Healthcare Infection Control Practices Advisory Committee. MMWR Recomm Rep 2004;53(RR-3):1-36.

Wayne P. Performance Standards for Antimicrobi- al Susceptibility Testing. 26th ed. CLSI supplement M100S. Clinical and Laboratory Standards Institute;2016.

Betrosian AP, Frantzeskaki F, Xanthaki A, Georgiadis G. High-dose ampicillin-sulbactam as an alternative treatment of late-onset VAP from multidrug-resistant Acinetobacter baumannii. Scand J Infect Dis 2007;39:38-43.

Khwaja A. KDIGO clinical practice guidelines for acute kidney injury. Nephron Clin Pract 2012;120(4):c179-184.

Koulenti D, Tsigou E, Rello J. Nosocomial pneumonia in 27 ICUs in Europe: perspectives from the EU-VAP/ CAP study. Eur J Clin Microbiol Infect Dis 2016;1-8.

Almomani BA, McCullough A, Gharaibeh R, Samrah S, Mahasneh F. Incidence and predictors of 14-day mortality in multidrug-resistant Acinetobacter bau- mannii in ventilator-associated pneumonia. J Infect Dev Ctries 2015; 9:1323-1330.

Carey RB BS, Srinivasan A. Multidrug-resistant acine- tobacter infections, 1995-2004. Presented at the 46th Interscience Conference on Antimicrobial Agents and Chemotherapy, San Francisco. 2006:27-30.

Mathai AS, Phillips A, Isaac R. Ventilator-associated pneumonia: A persistent healthcare problem in Indian Intensive Care Units. Lung India 2016; 33(5):512-516.

Tsioutis C, Kritsotakis EI, Karageorgos SA, Stratakou S, Psarologakis C, Kokkini S, et al. Clinical epidemi- ology, treatment and prognostic factors of extensively drug-resistant Acinetobacter baumannii ventilator-as- sociated pneumonia in critically ill patients. Int J Anti- microb Agents 2016 Nov;48(5):492-497.

Gales AC, Jones RN, Sader HS. Contemporary activ- ity of colistin and polymyxin B against a worldwide collection of Gram-negative pathogens: results from the SENTRY Antimicrobial Surveillance Program (2006-09). J Antimicrob Chemother 2011; 66:2070-2074.

Lin H-S, Lee M-H, Cheng C-W, Hsu P-C, Leu H-S, Huang C-T, et al. Sulbactam treatment for pneumonia involving multidrug-resistant Acinetobacter calcoace- ticus-Acinetobacter baumannii complex. Infect Dis (Lond) 2015 Jun;47(6):370-378.

Yilmaz GR, Guven T, Guner R, Tufan ZK, Izdes S, Tasyaran MA, et al. Colistin alone or combined with sulbactam or carbapenem against A. baumannii in ven- tilator-associated pneumonia. J Infect Dev Ctries 2015;9:476-485.

Zalts R, Neuberger A, Hussein K, Raz-Pasteur A, Gef- fen Y, Mashiach T, et al. Treatment of carbapenem-re- sistant Acinetobacter baumannii ventilator-associated pneumonia: retrospective comparison between intra- venous colistin and intravenous ampicillin-sulbactam. Am J Ther 2016; 23(1):e78-85.

Chu H, Zhao L, Wang M, Liu Y, Gui T, Zhang J. Sul- bactam-based therapy for Acinetobacter baumannii in- fection: a systematic review and meta-analysis. Braz J Infect Dis 2013; 17:389-394.

Ortwine JK, Sutton JD, Kaye KS, Pogue JM. Strategies for the safe use of colistin. Expert Rev Anti Infect Ther 2015; 13:1237-1247.

Inchai J, Pothirat C, Liwsrisakun C, Deesomchok A, Kositsakulchai W, Chalermpanchai N. Ventilator-as- sociated pneumonia: epidemiology and prognostic indicators of 30-day mortality. Jpn J Infect Dis 2015;68:181-186.

Falagas ME, Bliziotis IA, Siempos II. Attributable mor- tality of Acinetobacter baumannii infections in critical- ly ill patients: a systematic review of matched cohort and case-control studies. Crit Care 2006; 10(2):R48.

Betrosian AP, Frantzeskaki F, Xanthaki A, Douzinas EE. Efficacy and safety of high-dose ampicillin/sul- bactam vs. colistin as monotherapy for the treatment of multidrug resistant Acinetobacter baumannii venti- lator-associated pneumonia. J Infect 2008; 56:432-436.

Desai K, Kazi M, Ajbani K, Munshi M, Rodrigues C, Soman R, et al. Clinical outcomes and safety of colistin in treatment of Gram negative infections: A prospec- tive observational study. The Egyptian Crit Care Med 2016; 4:67-72.

Falagas ME, Kasiakou SK. Colistin: the revival of polymyxins for the management of multidrug-resis- tant Gram-negative bacterial infections. Clin Infect Dis 2005; 40:1333-1341.

Tacconelli E, De Angelis G, Cataldo MA, Mantengo- li E, Spanu T, Pan A, et al. Antibiotic usage and risk of colonization and infection with antibiotic-resistant bacteria: a hospital population-based study. Antimicrob Agents Chemother 2009; 53:4264-4269.

D'Agata EM, Venkataraman L, DeGirolami P, Burke P, Eliopoulos GM, Karchmer AW, et al. Colonization with broad-spectrum cephalosporin-resistant Gram-nega- tive bacilli in intensive care units during a nonoutbreak period: prevalence, risk factors, and rate of infection. Crit Care Med 1999; 27:1090-1095.

How to Cite
Shojaei L, Mohammadi M, Beigmohammadi M-T, Doomanlou M, Abdollahi A, Feizabadi M-M, Khalili H. Clinical response and outcome of pneumonia due to multi-drug resistant Acinetobacter baumannii in critically ill patients. IJM. 8(5):288-97.