Aerosolized colistin in the treatment of multiresistant Pseudomonas aeruginosa nosocomial pneumonia

Abstract

Introduction. Multiresistant Pseudomonas aeruginosa (MRPA) nosocomial pneumonia is a significant cause of mortality and morbidity in the ICU. We report our experience with aerosolized colistin in the treatment of MRPA nosocomial pneumonia. Patients and methods. It is a prospective, observational study performed over 2 years (2006-2007). Patients who developed MRPA nosocomial pneumonia and were treated with aerosolized colistin were included. The criteria used to assess if treatment was successful were extubation and ICU mortality rates. Results. We report 32 patients of whom 12 were women and 20 men. The mean age was 48 ± 19 years. All patients were receiving mechanical ventilation. The mean length of ventilation was 22 ± 5.5 days. The bronchial sampling technique used was broncho-alveolar lavage. The mean delay of infection (duration between intubation and pneumonia diagnosis) was 7 ± 2 days. Isolated MRPA was susceptible only to colistin. The treatment was aerosolized colistin for all patients (4 MUI/day). A positive blood culture (n=5) was a prerequisite for administering colistin intravenously (4 MUI/day). Any potential toxicity was observed. The mean delay of extubation after starting treatment was 10 days. Sterile samples were obtained on average by the eighth day. No deaths were recorded. Conclusion. It seems that aerosolized colistin is an important alternative to treat MRPA nosocomial pneumonia in ICU. Our results need further confirmation by other multicentre studies.