EVALUATION OF PULSED-FIELD GEL-ELECTROPHORESIS AS A TYPING SYSTEM FORCANDIDA-RUGOSA - COMPARISON OF KARYOTYPE AND RESTRICTION-FRAGMENT-LENGTH-POLYMORPHISMS
Jc. Dib et al., EVALUATION OF PULSED-FIELD GEL-ELECTROPHORESIS AS A TYPING SYSTEM FORCANDIDA-RUGOSA - COMPARISON OF KARYOTYPE AND RESTRICTION-FRAGMENT-LENGTH-POLYMORPHISMS, Journal of clinical microbiology, 34(6), 1996, pp. 1494-1496
Nosocomial infections with Candida species have emerged as an increasi
ngly important cause of morbidity and mortality in intensive care unit
s. Ten Candida rugosa isolates from a previously documented cluster of
C. rugosa infections in one hospital (nine burn unit isolates and one
isolate from another hospital ward) and eight C. rugosa isolates reco
vered in a referral fungus testing laboratory (comparison isolates) fr
om distinct geographic areas were investigated by molecular techniques
. Isolates were from multiple anatomic sites. Pulsed-field gel electro
phoresis (PFGE) of whole-cell DNA was performed with the 18 C, rugosa
isolates as a marker of strain identity. The PFGE karyotypes of the C.
rugosa isolates were demonstrated from four to seven chromosome bands
. Karyotyping revealed the same PFGE pattern for the nine outbreak iso
lates from the burn unit, confirming clonal strain transmission. The i
solate from the other hospital ward had a distinct karyotype, Distinct
PFGE karyotype patterns were demonstrated for the eight comparison is
olates. Restriction fragment length polymorphisms (RFLP) generated fro
m whole-cell DNA digested with SfiI demonstrated the same RFLP pattern
among outbreak isolates. Among comparison isolates, karyotyping disti
nguished some isolates that were indistinguishable by RFLP patterns, K
aryotyping by PFGE appears to be the most useful molecular typing tool
for discrimination among strains of C. rugosa and will be a useful ma
rker for evaluating the epidemiology of future C. rugosa infections.