Describing the Utility of Fungal Blood Cultures in Patients Hospitalized at a Large Pediatric Academic Center.

BACKGROUND

Routine blood cultures (BCs) are frequently obtained in hospitalized children with suspected infection. Although bacterial pathogens are the primary concern, fungal infections remain a consideration in high-risk populations, prompting clinicians to order fungal blood cultures (FBCs) in addition to routine BCs. However, given the prolonged incubation time and labor-intensive nature of FBCs, their incremental diagnostic value beyond routine BCs is uncertain.

METHODS

We performed a retrospective, single-center study of hospitalized children 0-18 of age years at the Children's Hospital of Philadelphia between October 2015 and December 2022. Electronic health record data were used to identify all FBCs and associated BCs obtained during hospitalizations lasting ≥24 hours. Demographic and clinical characteristics, including admitting service, neutropenia status and presence of a central venous catheter, were collected. Culture results were grouped into diagnostic episodes by hospitalization. FBC results were compared with BCs obtained within 5 days to assess diagnostic yield and clinical utility, defined as identification of a unique organism leading to a change in clinical management.

RESULTS

A total of 540 FBCs were ordered for 244 patients across 159,563 inpatient admissions, representing 296 diagnostic episodes. Patients were predominantly male, non-Hispanic, and White, with 28.7% younger than 1 year. Most diagnostic episodes occurred in oncology, hematology, transplant, critical care or surgical settings; 25.3% involved patients with central venous catheters and 17.2% with neutropenia. Fifty-four FBCs were positive, corresponding to 22 diagnostic episodes (7.4%). Most positive cultures grew fungal pathogens, commonly Candida parapsilosis , Trichosporon asahii and Candida albicans . Only 1 FBC identified an organism not detected on routine BCs, and this finding did not alter the management.

CONCLUSIONS

Over 7 years, FBCs provided no additional clinically actionable information beyond routine BCs. These findings support diagnostic stewardship efforts to limit routine FBC use and clarify scenarios in which they may be beneficial.