title: Is catheter-related candidemia a polyclonal infection?
abstract: Diagnosis of catheter-related candidemia (CRC) requires the simultaneous isolation of Candida spp. from both blood and catheter samples. We previously observed that in most CRC cases, the genotype of the yeast found in catheter samples is also recovered from blood. However, it is not clear whether CRC is a polyclonal infection. We prospectively studied 20 patients with CRC caused by Candida albicans, C. parapsilosis, or C. glabrata to analyze whether their infections were polyclonal. As many as 10 colonies per sample (n = 475) isolated from blood (n = 220) and catheter (n = 255) specimens were studied using species-specific microsatellite markers. Genotyping always revealed matches between the Candida spp. from blood and catheter samples. However, 15% of patients had a polyclonal pattern of infection or catheter colonization that was species specific. An additional genotype was found exclusively in the catheters of two patients infected with C. albicans, whereas an additional genotype was noted in the blood culture of a patient infected with C. parapsilosis. Considering only the presence of different genotypes in blood samples, 5% of patients had polyclonal infections. We conclude that most cases of CRC are caused by a single genotype.
authors.affiliation: Clinical Microbiology and Infectious Diseases, Hospital General Universitario Gregorio Marañón, Madrid.
authors.forename: P
authors.initials: P
authors.lastname: Escribano
authors.forename: J
authors.initials: J
authors.lastname: Guinea
authors.forename: L J
authors.initials: LJ
authors.lastname: Marcos-Zambrano
authors.forename: P
authors.initials: P
authors.lastname: Martín-Rabadán
authors.forename: A
authors.initials: A
authors.lastname: Fernández-Cruz
authors.forename: C
authors.initials: C
authors.lastname: Sánchez-Carrillo
authors.forename: P
authors.initials: P
authors.lastname: Muñoz
authors.forename: E
authors.initials: E
authors.lastname: Bouza
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001769:Blood / Q000382:microbiology; D002175:Candida / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D058387:Candidemia / Q000453:epidemiology / Q000382:microbiology*; D055499:Catheter-Related Infections / Q000453:epidemiology / Q000382:microbiology*; D057785:Catheters / Q000382:microbiology; D060085:Coinfection / Q000453:epidemiology / Q000382:microbiology*; D005260:Female; D005838:Genotype; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D018895:Microsatellite Repeats; D008875:Middle Aged; D058889:Molecular Typing; D016533:Mycological Typing Techniques; D011446:Prospective Studies
keywords: C. albicans; C. glabrata; C. parapsilosis; blood culture; candidemia; catheter culture; catheter-related candidemia; genotyping; microsatellites; polyclonal