Clinico-microbiological study of infections in the intensive care unit and study of antimicrobial resistance in bacterial isolates.

Infectious disease specialists have long recognized that the risk of ICU patients acquiring nosocomial infections is 5-10 times greater than those in general wards. Several factors such as severe underlying disease, multiple illnesses, malnutrition, extremes of age, immunosuppression, use of invasive medical devices, ICU crowding and animate reservoirs increase the risk of acquiring infections in the ICU. Out of 113 isolates obtained in our study, 32.7% were from ventilator-associated pneumonia patients and 17.7% from urinary tract infection patients. The major isolates were Staphylococcus aureus (21.2%) and Klebsiella spp. (20.4%). Methicillin resistant Staphylococcus aureus (MRSA) and ESBL producing Klebsiella and E. coli were the major drug resistant bacteria isolated and associated with significant mortality. Control of these infections poses a major problem in treating the patients because of the rising trend of drug resistance among these bacteria.

ESBLs — A Challenge to the Clinicians.

Introduction: Treatment of extended spectrum betalactamase (ESBL) producing strains of Enterobacteriaceae has emerged as a major challenge in hospitalized critical as well as community based patients. Infections due to ESBL producers range from uncomplicated urinary tract infection to life threatening sepsis. Methods: We conducted a study to detect the presence of these enzymes in isolates in tertiary care hospital. A total 318 non-repetitive isolates were screened for resistance to any of five screening agents by CLSI (formerly NCCLS) disc diffusion method. Those with suspicious profile were checked for ESBL production by phenotypic confirmation test as recommended by CLSI Disc potentiation method. Various cephalosporin- b-lactamase inhibitor combinations were also tested. Results: Of the 269(84.59%) screen-positive isolates, only 219(81.41%) were identified as ESBL producers. From 219, only 136(62.10%) of Escherichia coli and 83(37.89%) Klebsiella pneumoniae were ESBL producers. Conclusion: Tests for the detection of ESBL producing Escherichia coli and Klebsiella pneumoniae should be carried out in all diagnostic centres routinely because drug resistance patterns are constantly changing.