Identification and molecular characterization of mannitol salt positive, coagulase-negative staphylococci from nasal samples of medical personnel and students.
The identification of mannitol salt positive, coagulase-negative staphylococci (CNS) is often disregarded when Staphylococcus aureus is screened in clinical samples using mannitol salt agar. However, the emergence of CNS as important human pathogens has indicated that reliable methods for the identification of clinically significant CNS are of great importance in understanding the epidemiology of infections caused by them. The identification and molecular characterization of mannitol salt positive CNS from nasal samples of medical personnel and students is reported here. A total of 84 mannitol salt positive staphylococcal isolates were obtained from 240 nasal samples, of which 15 were CNS. The API STAPH system classified the CNS isolates into six species, and one-third of the isolates were identified with confidence levels of <80 %. 16S-23S rRNA intergenic spacer length polymorphism analysis (ITS-PCR) identified only two species (Staphylococcus haemolyticus and Staphylococcus saprophyticus). This identification was confirmed by antibiotyping, species-specific PCR and PFGE. The results from this study indicate that ITS-PCR is a potentially useful and reliable tool, enabling hospital laboratories to obtain rapid, full and accurate identification of CNS at the species level.
Shittu
Adebayo
A
School of Biochemistry and Microbiology, University of KwaZulu-Natal, Private Bag X54001, Durban 4000, Republic of South Africa.
Lin
Johnson
J
School of Biochemistry and Microbiology, University of KwaZulu-Natal, Private Bag X54001, Durban 4000, Republic of South Africa.
Morrison
Donald
D
Scottish MRSA Reference Laboratory, Microbiology Department, Stobhill Hospital, Glasgow G21 3UW, UK.
Kolawole
Deboye
D
Department of Microbiology, Obafemi Awolowo University, Ile-Ife, Nigeria.
D015373:Bacterial Typing Techniques; D002353:Carrier State / Q000382:microbiology; D003030:Coagulase / Q000378:metabolism*; D004269:DNA, Bacterial / Q000032:analysis; D021903:DNA, Ribosomal Spacer / Q000032:analysis*; D016521:Electrophoresis, Gel, Pulsed-Field; D006801:Humans; D008353:Mannitol / Q000378:metabolism*; D008826:Microbial Sensitivity Tests; D009666:Nose / Q000382:microbiology*; D010820:Physicians; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012338:RNA, Ribosomal, 23S / Q000235:genetics; D011933:Reagent Kits, Diagnostic; D013045:Species Specificity; D013203:Staphylococcal Infections / Q000382:microbiology; D013210:Staphylococcus / Q000145:classification* / Q000201:enzymology / Q000235:genetics; D013337:Students, Medical
D003030:Coagulase; D004269:DNA, Bacterial; D021903:DNA, Ribosomal Spacer; D012336:RNA, Ribosomal, 16S; D012338:RNA, Ribosomal, 23S; D011933:Reagent Kits, Diagnostic; D008353:Mannitol