The most common clinical condition associated with Acinetobacter sp. is hospital-acquired pneumonia (HAP), particularly for patients receiving mechanical ventilator assistance. Multidrug-resistant Acinetobacter baumannii (MDRAB) is an important and emerging hospital-acquired pathogen worldwide. The basic purpose of this study was to evaluate (on the basis of evidence), whether we were justified in treating respiratory tract Acinetobacter sp. isolates with high grade antibiotics, or were we overprescribing and inadvertently contributing to antibiotic resistance. This was evaluated by calculating the relative risks of development of (Probable) Ventilator Associated Pneumonias in mechanically ventilated patients, whose Respiratory tract is colonized with Acinetobacter. Also, the Antibiotic Resistance patterns of hospital  Acinetobacter isolates were studied. In addition, the role of basic infection control measures in controlling the rates of Acinetobacter colonisations and infections in ICU patients was studied.

Results: (1) 20% of mechanically ventilated patients was colonised with Acinetobacter sp., of which, only 5.8% developed P-VAPs (2) Relative Risk for development of P-VAP in mechanically ventilated patients colonised with Acinetobacter sp. was 4.23 times higher than those not harbouring Acinetobacter sp. in their respiratory tract. (3) Sensitivity to antibiotics of Hospital Respiratory Acinetobacter strains was as follows: Colistin (100%)> Levofloxacin (64.4%)> Meropenem (60%)> Minocycline (24.4%)> PipTaz (13.3%). All hospital strains were MDRs (Multi Drug Resistant). (4) Relative risk of developing an AP-VAP (Acinetobacter P-VAP) can be reduced by 2.35 times by implementing Infection Control measures.

Conclusion: Using antibiotic coverage for all respiratory Acinetobacter sp. isolates, is probably counterproductive, since, it increases the selective antibiotic pressure, which enables, emergence of multi-drug resistance in Acinetobacter sp. Also, it was found that strict implementation of simple hospital infection control measures could reduce the colonization rates by half, and P-VAP rates by more than 2 times.

Keywords- Acinetobacter sp., VAP (Ventilator Associated Pneumonia), HAP (Hospital Acquired Pneumonia), CRA (Carbapenem Resistant Acinetobacter)

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Anisa Pal

Consultant Microbiologist (MD) and Hospital Infection Control Officer

Jabalpur Hospital and Research Centre, Jaabalpur, Madhya Pradesh, India

Tel: 9662740857, Email: This email address is being protected from spambots. You need JavaScript enabled to view it.