Definition and Use
- Fungal blood cultures are used for detection of bloodstream infection caused by fungi, especially when dimorphic species and uncommon pathogens are suspected. Identification, susceptibility, and further testing can be performed on culture isolates. The culture is indicated primarily for patients with cancer, extensive therapy with broad-spectrum antibiotics, trauma, and HIV and other immunocompromising conditions and symptoms that suggest sepsis, like fever, chills, malaise, hypotension, poor perfusion, toxicity, tachycardia, and hyperventilation. Biphasic and lysis " “centrifugation methods have demonstrated improved isolation of dimorphic and filamentous fungi.
- Turnaround time: 4 weeks
Special Collection and Transport Instructions
- Inoculate blood culture system according to the manufacturers recommendations. Alert the laboratory if infection due to Malassezia furfur is suspected. Special culture processing is needed for isolation of this lipophilic yeast. Transport to the laboratory at room temperature.
Interpretation
- Expected results: No growth
- Most commonly isolated pathogens in positive cultures:
- Yeasts: Candida albicans, nonalbicans Candida species, and Cryptococcus neoformans. (Candida and other commonly isolated yeasts may be efficiently detected using routine blood cultures.)
- Dimorphic fungus: Histoplasma capsulatum.
- Mold: Fusarium and Scedosporium species.
Limitation
- Aspergillus species are rarely isolated by blood culture even in the presence of acute systemic infection.
Suggested Reading
1CLSI. Principles and Procedures for Blood Cultures; Approved Guideline. CLSI document M47-A. Wayne, PA: Clinical and Laboratory Standards Institute; 2007.