Intravenous colistin in the treatment of sepsis from multiresistant Gram-negative bacilli in critically ill patients

Introduction The increasing prevalence of multiresistant Gram-negative strains in intensive care units (ICUs) has recently rekindled interest in colistin, a bactericidal antibiotic that was used in the 1960s for treatment of infections caused by Gram-negative bacilli. We conducted the present observational study to evaluate the efficacy of intravenous colistin in the treatment of critically ill patients with sepsis caused by Gram-negative bacilli resistant to all other antibiotics. Patients and method Critically ill patients with sepsis caused by Gram-negative bacilli resistant to all antibiotics with the exception of colistin were treated in the six-bed ICU of a trauma hospital. Diagnosis of infection was based on clinical data and isolation of bacteria, and the bacteria were tested with respect to their susceptibility to colistin. Clinical response to colistin was evaluated. Results Twenty-four patients (mean age 44.3 years, mean Acute Physiology and Chronic Health Evaluation II score 20.6) received 26 courses of colistin. Clinical response was observed for 73% of the treatments. Survival at 30 days was 57.7%. Deterioration in renal function was observed in 14.3% of 21 patients who were not already receiving renal replacement therapy, but in only one case did this deterioration have serious clinical consequences. Conclusion The lack of a control group in the present study does not allow any definite conclusions to be drawn regarding the clinical effectiveness of colistin. On the other hand, this drug has an acceptable safety profile and its use should be considered in severe infections with multiresistant Gram-negative bacilli.