Monitoring of Effectiveness and Safety of Colistin for Therapy in Resistant Gram-Negative Bacterial Infections in Hospitalized Patients at Siriraj Hospital
Visanu Thamlikitkul MD*, Sukhonthip Popum BNS**
Affiliation : * Department of Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand ** Department of Research and Development, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
Objective : To monitor the effectiveness and safety of colistin for therapy in resistant Gram-negative bacterial infections at
Siriraj Hospital 10 years after colistin was first introduced in Thailand at Siriraj Hospital in 2005.
Material and Method: Study subjects were hospitalized adult patients with documented Gram-negative bacterial infections
that received parenteral colistin (Colistate®) for longer than 48 hours between October 2014 and June 2015. Patient
information regarding demographics, characteristics of infections, antibiotic therapy, clinical outcomes, microbiological
responses, and nephrotoxicity were identified and retrieved from patient medical records. The data were analyzed using
descriptive statistics.
Results : One hundred thirty eight patients were included in the study. Many of the patients were elderly males. The most
common type of infection was pneumonia and A. baumannii was the most common cause of infection. Nearly all isolates of
A. baumannii and P. aeruginosa were resistant to carbapenems. A loading dose of colistin (300 mg) was given in 94.9% of
patients. Only 19.6% of patients received colistin alone. Most patients received concomitant antibiotics, especially
carbapenems, and piperacillin-tazobactam. Favorable clinical outcome was observed in 71.7% of patients at the end of
colistin therapy. Patient mortality at the end of colistin therapy and at 30 days after colistin therapy was completed was
23.2% and 39.9%, respectively. Microbiological eradication of target bacteria at the end of colistin therapy was found in
50.0% of patients. Overall incidence of acute kidney injury was 39.9%, with most cases classified as either risk (20.3%) or
injury (13%). Colistin-related renal dysfunction was reversible in most cases.
Conclusion : Colistin remains the principal antibiotic in carbapenem-resistant Gram-negative bacterial infections. Colistin’s
effectiveness and safety is still rated as moderate for therapy in difficult-to-treat resistant Gram-negative bacterial infections.
Keywords : Colistin, Effectiveness, Gram-negative bacterial infections, Safety
