Bacteriological profile of clinically significant Coagulase Negative Staphylococci isolated from various clinical specimens with special reference to the Virulence factors.

INTRODUCTION : Coagulase-Negative Staphylococci (CoNS) are ubiquitous microorganisms that predominate the normal skin flora. Due to their ubiquitous nature and relatively low virulence, CoNS have long been considered to be clinically insignificant, and hence when isolated from clinical specimens, the clinicians and the microbiologists discarded them as contaminants. However, it is noted that under appropriate conditions, CoNS can produce serious human diseases and the incidence of such infections has clearly increased in recent years. Moreover they are seen as one among the most commonly isolated organisms in the clinical microbiological laboratory. According to the National Nosocomial Infections Surveillance System, CoNS are among the five most commonly reported pathogens in hospitals. The postulated reasons for the current prevalence and clinical importance of these organisms include their great numbers on the skin, their selection as a result of wide spread usage of broad-spectrum antibiotics in the hospital, their ability to adhere to and form biofilm on the surfaces of vascular catheters and other medical devices, and their meager nutritional requirements. The emergence of CoNS as important potential pathogens is partly due to the increased usage of transient / permanent medical devices and partly due to the growing appreciation of this group of organisms as opportunistic pathogens. Infection caused by CoNS is increasingly common in patients having indwelling catheters, orthopedic appliances, prosthetic devices and urinary catheters. AIMS AND OBJECTIVES : The aim of the present study is to assess the various microbiological aspects of Coagulase-Negative Staphylococci (CoNS) and its clinical significance with special emphasis on demonstration of virulence factors and methicilin resistance. OBJECTIVES: 1. To identify CoNS among bacterial isolates from various clinical specimens. 2. Speciation and biotyping of CoNS isolates. 3. To ascertain the significance of pathogenic CoNS in causation of infections, by ...