Multidrug Resistant Gram Positive Pathogens with Special Reference to MRSA and Biofilm Production in ICU Patients: Recurrent Challenge for Clinicians

Gram positive pathogens mainly Staphylococcus aureus, Enterococcus and Coagulase Negative Staphylococcus are hospital acquired (HA) pathogens. HA strains are usually multidrug resistant (MDR). Monitoring of these strains is essential in order to control their spread in the hospital environment and transmission to the community. The objectives were to assess the prevalence of Gram positive pathogens in ICU patients and their drug resistance profile. Prevalence of methicillin Resistant Staphylococcus aureus (MRSA) was assessed. Health care workers (HCW) were screened for MRSA. Samples were collected aseptically from 150 ICU patients from February 2012 to November 2013. Culture, identification and antimicrobial susceptibility was performed according to CLSI guidelines. Pernasal swabs of HCW were collected for MRSA screening. Biofilm production among isolates was tested by the tube method. Among 143 bacterial isolates, 22 (13.8%) were gram positive while majority 121 (75.6%) were Gram negative. Staphylococcus aureus (9.4%) was the most common Gram positive pathogen isolated followed by Coagulase negative Staphylococcus (CoNS) (18.1%) and Enterococcus faecalis (2.4%). Among Gram positive bacterial isolates, S. aureus showed maximum resistance to clindamycin (73.3%), ofloxacin (75%) and gentamycin (66.7%). Sixty percent resistance was observed for oxacillin, levofloxacin and erythromycin each. Staphylococcus aureus isolates identified as MRSA were 66.7% and 60% by Oxacillin disc and Cefoxitin disc diffusion test respectively. Prevalence of MRSA was highest among surgical site infections(27.2%) followed by blood stream infections (20.7%)All the gram positive isolates (100%) were MDR. 13.4% of the HCW were MRSA carriers.None of the isolates were found resistant to vancomycin. Among the 22 bacterial isolates, 12 (54.5 %) were biofilm producers and all of them were MRSA. Resistance of Gram positive pathogens to commonly used antibiotics is alarmingly high. HCW are an important source of transmission of infection between hospitalized patients and they should acclimatize to proper hand washing and other simple infection control practices to inhibit such transmission. K e y w o r d s Multidrug resistant,