http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
A Study of Biofilm producing Staphylococcus aureus clinical isolates from patients of a tertiary care Teaching Hospital of Nepal
ABSTRACT: Staphylococcus aureus is an important nosocomial pathogen that can cause several infections. Moreover the rise of Methicillin Resistant Staphylococcus aureus (MRSA) has further complicated the treatment of Staphylococcol infections. Vancomycin has been the antibiotic of choice for the treatment of Staphylococcol infections caused by MRSA. But the rise in antibiotic failure and patient mortality has been a major problem due to shift in MIC of Vancomycin to higher level within susceptibility range. The ability of biofilm formation by S. aureus is one of the main causes of antibiotic resistance and treatment failure. This study sought to identify the effect of biofilm on Vancomycin MIC threshold value that is associated with an increased probability of failure. A cross sectional study was conducted at Bacteriology laboratory of Tribhuvan University Teaching Hospital, Kathmandu, Nepal from May 2017- October 2017. The main objective of this study was to find the association of biofilm production with antimicrobial resistance. Confirmation of MRSA was done by Cefoxitin disk diffusion method. Furthermore, the biofilm production of S. aureus was detected by Tissue Culture Plate method. MIC of Vancomycin was measured by E test for biofilm producing as well as biofilm non producing MRSA. In addition D-zone test was carried out for the detection of Inducible Clindamycin Resistance (ICR). Out of 217 isolates of S. aureus, 135 (62.2%) were biofilm producers. About 62.7% and 37.3% of MDR were biofilm producer and non biofilm producer respectively. MIC of Vancomycin among the MRSA (N=102) were found to be in susceptible range 0.125 - 2mg/ltr. Biofilm producing isolates showed higher MIC of Vancomycin than non biofilm producers (p-value<0.05). MRSA showed higher tendency of ICR than MSSA (p-value<0.05). Hence, the findings suggest that biofilm production is one of the main causes of increasing antimicrobial resistance. Key words: S. aureus, Methicillin Resistant Staphylococcus aureus, Inducible Clindamycin Resistance (ICR)
Methicillin Resistant Staphylococcus aureus