Blood stream infections by carbapenem resistant bacteria: critical perspectives from Indian tertiary care hospita

Abstract

Purpose: Emergence of Multi-Drug Resistance (MDR) Gram Negative Bacilli (GNB) is increasing at a faster pace, and carbapenems are the drug of choice for treatment. But rampant use of these agents has given rise to Carbapenem-Resistant Enterobacteriaceae (CRE). CRE causes wide range of infections, with Blood Stream Infection (BSI) associated with highest mortality. Thereby leaving colistin as the only available option for treatment. Our study was aimed, to measure the occurrence of CRE BSI in our institute. Methods & Materials: A prospective observational study was performed over six months (July-December 2017). Blood culture was performed by BacT/ALERT automated system followed by identification of isolates and susceptibility testing by MALDI-TOF (Vitek-MS) and VITEK 2 system (bioMerieux, Inc., Durham, NC). The clinical characters, demography and resistance profiles of patients with culture proven CRE BSI were studied. Results: Among the 53 patients, the mean (SD) age was 48.94 ± 20.66 years, with a male preponderance (M: F = 2.5:1). On admission, 62.3% patients received antibiotics. Secondary bacteremia and ICU admission seen in 88.7% and 71.7% respectively. Median (IQR) time to bacteremia (since admission), stay in ICU and hospital was 10 (11.5), 7 (11.5) and 19(18.5) days respectively. Diabetes mellitus (23) was the most common comorbid condition. Among the isolates, Klebsiella pneumoniae was the most common (26) followed by Acinetobacter baumannii complex (14). Lower respiratory tract (24.5%) was found to be the most common source followed by hepatobiliary tract (17%). Median (IQR) for Pitt's bacteremia (<24 hr of bacteremia) and SOFA score (on admission) was 4(4) and 7(8) respectively. About 96.2% of the isolates were sensitive to colistin and 47.2% to tigecycline. As per sensitivity, combination of drugs were started but Colistin was given in 43.4% cases. Adverse event was seen in 73.9% patients received colistin. Favorable outcome was not seen in 41.5% patients. Conclusion: CRE causing BSI is a significant threat to public health, warranting increased efforts towards strategies focusing on prevention, detection and infection control practices. Severe underlying conditions, use of invasive procedures and antibiotic selection pressure may predispose the patient to acquire CRE infection. Efficient management of underlying condition with optimal antibiotic may better the outcome.