Rapid, cost-effective, sensitive and quantitative detection of Acinetobacter baumannii from pneumonia patients

  • B Nomanpour Department of Microbiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
  • A Ghodousi Department of Microbiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
  • A Babaei Department of Anesthesiology, Shaheed Rajaei Cardiovascular, Medical & Research Center, Vali- Asr Avenue Tehran- Iran.
  • HR Abtahi Department of Internal Medicine, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
  • M Tabrizi Department of Medical Genetics, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
  • M Feizabadi Department of Microbiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran AND 5Pediatric Infection Diseas Research Center, Tehran, University of Medical Science, Tehran, Iran.
Keywords: HAP, VAP, Acinetobacter baumannii, Real time PCR, Pneumonia


Background and Objectives: Pneumonia with Acinetobacter baumannii has a major therapeutic problem in health care settings. Decision to initiate correct antibiotic therapy requires rapid identification and quantification of organism. The aim of this study was to develop a rapid and sensitive method for direct detection of A. baumannii from respiratory specimens.Materials and Methods: A Taqman real time PCR based on the sequence of blaoxa-51 was designed and used for direct detection of A. baumannii from 361 respiratory specimens of patients with pneumonia. All specimens were checked by conventional bacteriology in parallel.Results: The new real time PCR could detect less than 200 cfu per ml of bacteria in specimens. There was agreement between the results of real time PCR and culture (Kappa value 1.0, p value < 0.001). The sensitivity, specificity and predictive values of real time PCR were 100%. The prevalence of A. baumannii in pneumonia patients was 10.53 % (n = 38). Poly-microbial infections were detected in 65.71% of specimens.Conclusion: Acinetobacter baumannii is the third causative agent in nosocomial pneumonia after Pseudomonas aeroginosa (16%) and Staphylococcus aureus (13%) at Tehran hospitals. We recommend that 104 CFU be the threshold for definition of infection with A. baumannii using real time PCR.


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How to Cite
Nomanpour B, Ghodousi A, Babaei A, Abtahi H, Tabrizi M, Feizabadi M. Rapid, cost-effective, sensitive and quantitative detection of Acinetobacter baumannii from pneumonia patients. IJM. 3(4):162-9.