Abstract :
Background: Staphylococcus epidermidis is a normal commensal of the skin and mucous membrane of humans and animals. Despite the growing importance of its pathogenesis especially in neonatal septicemia and device associated infections, it is still considered as insignificant isolate in the clinical practice. Hence, the present study is taken up to analyze the sources and risk factors of the isolates and to know their antibiogram along with occurrence of Methicillin resistant S. epidermidis (MRSE).
Materials and Methods: 150 clinically significant S. epidermidis isolates from various clinical specimens were considered in this study. Species identification was done by phenotypic methods. The antimicrobial susceptibility test and detection of Methicillin resistance were performed by Kirby-Bauer’s disc diffusion method as per CLSI guidelines.
Results: Among 150 S. epidermidis isolates, 78% were recovered from hospital acquired infections. They were commonly isolated in pediatric age group (30%) and among males (60.67%). Total of 34.67% were isolated from pus samples followed by blood (25.33%). Most of the isolates were associated with multiple risk factors like hospitalization, prior antibiotic administration, foreign body in situ and ICU admission. Majority of the isolates expressed resistance towards Penicillin (93.33%), followed by
Amoxicillin-Clavulanic acid (76%), Cotrimoxazole (71.33%), Fluoroquinolones (64%), Gentamicin (60%) and Erythromycin (55.33%). Resistance against Amikacin (16.67%), Tetracycline (9.3%) and Linezolid (0.67%) was low. All isolates were sensitive to Vancomycin. Inducible Clindamycin resistance was 18% and MRSE was 68%.
Conclusion: Clinical importance and emergence of drug resistance among S. epidermidis infections is growing with the advent of advanced medicine. This warrants the need to implement simple laboratory methods for species identification of the S. epidermidis and to determine the antibiotic resistant patterns on routine basis. Clinical correlation of the isolate is crucial to rule out the colonizers and contaminants.
Keyword :
MRSE, CoNS, Cefoxitin, Blood, Device