Clinical experiment with the use of colistin for the treatment of multiresistant Acinetobacter baumanii nosocomial infection

Introduction

Intravenous and aerosolized colistin are being used increasingly, in the critical care setting, for treating patients with nosocomial infections due to multidrug-resistant Gram-negative bacteria. The objective of this study was to report our experience of colistin use in multiresistant Acinetobacter baumanii.

Methods

A retrospective review of patients' charts for those admitted to the surgical intensive unit, between September 2007 and September 2008. Infected patients with multiresistant acinetobacter treated with intravenous and aerosolized colistin were reviewed.

Results

Fifteen patients were identified, 13 men and two women. The patients ranged in age from 21 to 65 years. The patients were admitted to intensive care for polytrauma (10 cases), chest trauma (three cases) and cerebrovascular accident (two cases). The main infections were ventilator nosocomial pneumonia (100%), surgical site infection (6.6%), primary bacteremia (13%), catheter infection (20%), and meningitis (13%). The bacteria responsible were A. baumanii (100%), Pseudomonas aeruginosa (46%), Staphylococcus aureus (26%), Klebsiella pneumoniae (6%), Enterobacter cloacae (6%), and Morganella morganii (6%). All patients had normal renal function at the onset of antibiotic therapy. Five patients received colistin monotherapy, six patients received combination therapy colistin with imipenem or third-generation cephalosporin, and four patients received colistin with teicoplanine. The colistin was used at 4 mg/kg/day administered intravenously and aerolized colistin at 2 mg/kg for 8 to 16 days. A favourable response was observed in 12 cases. Overall mortality was three cases. Colistin induced reversible nephrotoxicity in one case and a reversible neuropsychiatric event was observed in one case. Bacterial eradication was confirmed in 14 patients (93%).

Conclusion

Garnacho-Montero and colleagues reported that intravenous colistin was as effective as imipenem [1]. Our findings with colistin can be considered encouraging in comparison with previous experience.