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
Canine parvovirus-2: an insight into molecular diagnosis and characterization methods
Canine parvovirus is an extremely contagious and serious disease caused by Canine parvovirus type 2 (CPV-2). The disease was first reported in 1978 and since then it continues to pose a severe threat to world canine popu...
Evaluation of purity, viability, stability and biochemical characteristics of clinical fungal isolates preserved by three different methods
Introduction In era of organ transplants and immunocompromised patients systemic mycosis has emerged as a major cause of morbidity and mortality among these patients Research on these clinical fungal isolates is the key...
Resistant Genes blaCTX-M, blaTEM and blaSHV encoding ESBL in surgical site infection causing Escherichia coli and Klebsiella pneumoniae- A report from a tertiary care hospital
Introduction Surgical site Infections SSI rank third among hospital acquired infections worldwide According to the WHO report of 2016 the global burden of SSI ranges from 25 to 415 ESBL producing Ecoli and Klebsiella pne...
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...
Etiology and risk factors of catheter associated urinary tract infections in ICU patients
Background: Catheter associated urinary tract infections (CAUTI) are common infections in ICUs patients. Unnecessary treatment of CAUTI causes economic burden on healthcare and contributes to antibiotic resistance. Objec...