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
Polymerase chain reaction versus culture in the diagnosis of extrapulmonary tuberculosis-A comparative study
Introduction: Extrapulmonary tuberculosis (EPTB) accounts for approximately 40% of tuberculosis cases and is a significant health problem in both developing and developed countries. Extrapulmonary TB represents a greater...
PUS culture isolates and their antibiotic sensitivity at a Tertiary Care Hospital in Hyderabad Karnataka Region
Introduction: Different studies show that aerobic bacteria are the majority of isolates causing pyogenic infection. Even though the bacterial profile of pus samples in many studies remain the same, the antibiotic resista...
Antibiotic resistance pattern of Uropathogens in a tertiary care hospital of Central India
Background: Urinary tract infection is one of the most common bacterial infections in human being. The causative agent of UTI varies from place to place and they also vary in their resistance pattern. Objective: This stu...
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...
Study of Vulvo-Vaginal Candidiasis among Patients Visiting Obstetrics and Gynecology Department in a Tertiary Care Centre
Background: Vulvovaginitis is a common day to day problem in gynecological practice. Candida albicans is the commonest infectious cause. An estimated 75% of women have at least one episode of Vulvo-vaginal Candidiasis an...