PNA FISH™

Yeast - C. albicans/C. glabrata PNA FISH

For in vitro diagnostic use.

C. albicans/C. glabrata PNA FISH™ (Cat. No. KT006) is a multicolor, qualitative nucleic acid hybridization assay intended for identification of Candida albicans and Candida glabrata from blood cultures.

C. albicans/C. glabrata PNA FISH provides rapid identification of C. albicans and C. glabrata on smears made directly from Yeast-positive blood cultures and is compatible with all major blood culture media. The 2.5 hours fluorescence in situ hybridization (FISH) assay uses fluorescently labeled peptide nucleic acid (PNA) probes that target the species-specific ribosomal RNA (rRNA) of C. albicans and C. glabrata. Results are visualized using fluorescence microscopy. Green fluorescing cells identify C. albicans while red fluorescing cells identify C. glabrata. The absence of fluorescence indicates another species is present in the positive blood culture.

Features and Benefits

Results Reporting - Rapid Identification of Yeast+ Blood Cultures

Once a blood culture turns positive, a Gram stain is performed. If the Gram stain reveals Yeast, C. albicans/C. glabrata PNA FISH is performed and within a few hours, results are available and can be reported to the attending physician.

Optimizing Antifungal Therapy for Candidemia
- Ensure Appropriate Therapy for C. albicans, C. glabrata and other Yeast Species
- Reduce Unnecessary and Expensive Antifungal Use

Candidemia is a bloodstream infection that is initially diagnosed when a blood culture turns positive with Candida species. It is one of the most serious hospital-acquired infections and is on the rise due to the increasing population of immuno-compromised transplantation, oncology and AIDS patients. The infection is associated with a high mortality rate and can be difficult to treat due in part to increasing resistance to antifungal agents in such species as Candida glabrata.

According to “Guidelines for Treatment of Candidiasis” published by the Infectious Diseases Society of America (IDSA), “knowledge of the infecting species, however, is highly predictive of likely (antifungal) susceptibility and can be used as a guide to therapy”. While antifungal therapy can be based on species identification, conventional laboratory methods can take up to 5 days or more. As a result, patients are often treated empirically with broad-spectrum agents which are known to be nephrotoxic, expensive or both.(1)

The guidelines published by IDSA also state that for candidemia due to C. albicans without prior azole exposure, fluconazole is appropriate as first-line therapy while for non-C. albicans species, such as C. glabrata, broad-spectrum agents may be considered due to the risk of fluconazole resistance.(2,3)

C. albicans/C. glabrata PNA FISH provides rapid identification of C. albicans and C. glabrata directly from Yeast-positive blood cultures. Results are available in hours, instead of days, allowing labs to quickly report results to physicians and pharmacists, and helping to ensure optimal therapy for patients with candidemia. A study published in the Journal of Clinical Microbiology showed that implementing PNA FISH and incorporating the rapid species identification results into the treatment algorithm for candidemia resulted in:

• Antifungal drug savings of $1,808 per candidemia patient for 72 patients (total of $130,231)

• Time to identification of C. albicans reduced to same day with PNA FISH from an average of 44 hours (range, 36 to 92 hours) by conventional methods

• For 72 patient samples tested, PNA FISH was 100% sensitive and specific and confirmed that conventional microbiology methods mis-identified 6 C. dubliniensis as C. albicans

1. Fridkin et al. The changing face of fungal infections in health care settings. Clin Infect Dis. 2005 Nov 15;41(10):1455-60. - Link

2. Pfaller et al. Trends in Antifungal Susceptibility of Candida spp. Isolated from Pediatric and Adult Patients with Bloodstream Infections: SENTRY Antimicrobial Surveillance Program J. Clin. Microbiol. 2002 Mar.;40(3)852-63. - Link

3. Pappas et al. Guidelines for treatment of candidiasis. Clin. Inf. Dis. 2004 Jan. 15;38(2):161-89. - Link

4. Forrest et al. Peptide nucleic acid fluorescence in situ hybridization-based identification of Candida albicans and its impact on mortality and antifungal therapy costs. J. Clin. Microbiol. 2006 44: 3381-3383. - Link