A nationwide survey of clinical laboratory methodologies for fungal infections

Many hospitalized patients are at risk for fungal infections. In order to characterize present clinical laboratory experience and facilities for diagnosis and management of fungal infections, a nationwide survey of laboratory diagnostic methodologies was conducted. Data from calendar year 1988 were collected from 71 institutions (52 university teaching hospitals and 19 community hospitals) enrolled in the Drug Surveillance Network. Surveyed hospitals received 75,828 specimens for fungal culture in 1988, representing 18,705 positive cultures from 7373 patients. About 1.3% of patients admitted to teaching or community hospitals had positive fungal cultures, the most common isolates being Candida species. Yeast identification was most commonly performed by the germ tube test and carbohydrate assimilation testing. Dimorphic fungi were identified to the species level at 67% of hospitals. Cryptococcal antigen testing was available at all hospitals, and Candida serology testing was done at 55 institutions. A small number of hospitals performed antifungal drug concentration determinations for amphotericin B (n = 9), ketoconazole (n = 7) and flucytosine (n = 12). Fungal susceptibility testing was available at 77% of hospitals, either within the institution or at an external laboratory. Laboratory testing for diagnosis and management of fungal infections represents a major laboratory investment. Proficiency in this area, along with expert clinical advice, will be needed to advance therapy of patients complicated with fungal infections during the next decade.