title: The significance of coagulase-negative staphylococci bacteremia in a low resource setting.
abstract: BACKGROUND
  Coagulase-negative staphylococci (CoNS) are a group of micro-organisms that are increasingly implicated as a cause of significant infection and the leading cause of bloodstream infection (BSI). One important predictor of true BSI is the isolation of CoNS from multiple blood cultures, presuming that the isolates represent the same species. Thus the objective of this study was to determine the significance of repeated CoNS isolated from blood cultures.
  
  
  METHODS
  This was a prospective laboratory study which was initiated in June 2007 and lasted until July 2008. CoNS isolates were obtained from patients who had two positive blood cultures within a 14-day interval. CoNS were identified to the species level using an API-Staph, and antibiotics susceptibility testing was performed according to Clinical and Laboratory Standards Institute specifications. Strain relatedness was confirmed using pulsed-field gel electrophoresis.
  
  
  RESULTS
  During the study period, 202 CoNS-positive samples were isolated from 101 patients. The most common species isolated was Staphylococcus epidermidis (59.0%), and 83.2% of the patients isolated the same species of CoNS from repeated blood cultures. Among the isolates of the same species, only 40.7% had the same antibiogram. CoNS with the same species and antibiogram had 93.3% probability of belonging to the same strain. Most (65.5%) of the patients were treated with antibiotics, primarily from the glycopeptides group.
  
  
  CONCLUSIONS
  Speciation and antibiogram of CoNS from repeated blood cultures are adequate in determining the significance of repeated CoNS isolated from blood cultures.
authors.affiliation: School of Medical Sciences, Universiti Sains Malaysia, Malaysia. drzaidah@kb.usm.my
authors.forename: Zaidah
authors.initials: Z
authors.lastname: Abdul Rahman
authors.forename: Siti Hawa
authors.initials: SH
authors.lastname: Hamzah
authors.forename: Siti Asma'
authors.initials: SA
authors.lastname: Hassan
authors.forename: Sabariah
authors.initials: S
authors.lastname: Osman
authors.forename: Siti Suraiya
authors.initials: SS
authors.lastname: Md Noor
mesh_terms: D000328:Adult; D016470:Bacteremia / Q000453:epidemiology* / Q000382:microbiology; D015373:Bacterial Typing Techniques; D003030:Coagulase / Q000172:deficiency*; D003906:Developing Countries; D016521:Electrophoresis, Gel, Pulsed-Field; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008296:Malaysia / Q000453:epidemiology; D008826:Microbial Sensitivity Tests; D058889:Molecular Typing; D011446:Prospective Studies; D013203:Staphylococcal Infections / Q000453:epidemiology* / Q000382:microbiology; D013210:Staphylococcus / Q000145:classification / Q000235:genetics / Q000302:isolation & purification* / Q000502:physiology
chemical_list: D003030:Coagulase