A study on determination of Minimum Inhibitory Concentration (MIC) of Vancomycin of MRSA Isolates and their impact in treatment of MRSA Isolates
Journal Title: IP International Journal of Medical Microbiology and Tropical Diseases - Year 2017, Vol 3, Issue 1
Abstract
Introduction: Staphylococcus aureus is one of the most common causes of nosocomial infections. Methicillin-resistant S. aureus (MRSA) is among the top three clinically important pathogens. The glycopeptide vancomycin is considered to be the best alternative for the treatment of MRSA. MRSA usually exhibit vancomycin-susceptible phenotype (VSSA) but some strains exhibit reduced susceptibility to vancomycin which can be heterogeneous-intermediate (hVISA), intermediate (VISA) or fully resistant (VRSA) phenotypes which results in treatment failure. More recently, poor clinical outcome is observed in infections with MRSA strains with an elevated levels of vancomycin MIC within the susceptible range. Aim: This study was done to know the prevalence of MRSA and to determine the vancomycin MIC. Materials & Methods: S.aureus isolated from clinical samples were screened for methicillin resistance using cefoxitin discs (30 μg). The vancomycin MIC of these MRSA isolates was determined using E-strips. Results & Discussion: A total of 102 isolates of S.aureus were subjected to study. Among these, 42 isolates were MRSA (41.2%). The different MIC values are as follows: 0.38 μg/mL (2 isolate), 0.75 μg/mL (1 isolate), 1 μg/mL (3 isolates), 1.5 μg/mL (32 isolates) & 2 μg/mL (4 isolates). Although all the MRSA strains were within the susceptible range of vancomycin MIC, their increased MIC values (>1 μg/mL) can lead to treatment failures. Conclusion: Increased risks of treatment failure has been observed in infections caused by MRSA isolates with vancomycin MIC in the upper end of susceptible range (MIC > 1µg/ml), emphasising the need for determination of vancomycin MIC to assess the treatment outcome.
Authors and Affiliations
Mathavi Suresh Kumar, Vijai Radhika, Kavitha A, Sasikala G, Indra Priyadharsini
Bacteriological profile and antibiogram of urinary tract infections at a tertiary care hospital
A prospective laboratory based observational study collaborating with medicine, surgery, paediatrics, nephrology, urology, obstetrics & gynaecology and STD departments was carried out over a period of one year with 500 p...
Evaluation of Malaria Surveillance System in Hooghly district of West Bengal - India
Background: Malaria is endemic in 109 countries worldwide leading to approximately 1 million deaths. In 2009, West Bengal reported 89443 malaria cases including 24453 falciparum malaria. Hooghly district had ABER in the...
Anti-biogram of pneumococcal isolates in a tertiary care hospital
Streptococcus pneumoniae are gram positive normal flora of the upper respiratory tract in humans but are also the primary causative bacterial agents of pneumonia and otitis media mostly in children They are also known to...
De novo daptomycin non-susceptible enterococci causing urinary tract infection: a study from north India
Introduction Daptomycin is a bactericidal agent active against vancomycin resistant enterococci VRE which are emergent nosocomial uropathogens There is limited data available on daptomycin nonsusceptible enterococci DNSE...
Phenotypic detection of ESBL among E.coli and Klebiella pneumoniae by CLSI guidelines in a Teaching Hospital MIMS, Mandya
Introduction Escherichia coli and Klebsiella pneumoniae cause a wide range of infections Multidrugresistance strains carrying resistance genes have become a growing problem worldwide The ESBLs have emerged distinctly esp...