Investigation of a pseudo-outbreak of Burkholderia cepacia complex caused by contaminated phosphate-buffered saline.

BACKGROUND

Burkholderia cepacia complex (BCC) is a cause of health care-associated infections in immunocompromised patients and people with cystic fibrosis (PwCF). This report summarizes a B contaminans pseudo-outbreak related to improper laboratory processes affecting surgical specimens from immunocompetent individuals and respiratory cultures from PwCF.

METHODS

In October 2024, an increase in BCC isolates involving surgical, respiratory, and urine specimens occurred at an academic tertiary hospital. An investigation was launched involving the electronic clinical surveillance system, environmental surveillance, and review of laboratory processes. Species identification and genotyping was performed with randomly amplified polymorphic DNA (RAPD) typing. Whole genome sequencing (WGS) was completed for clonality analysis.

RESULTS

A total of 19 BCC isolates were included, 17 collected for clinical indications and 2 from reagents during the investigation. BCC was recovered from phosphate-buffered saline (PBS) used for rehydrating surgical samples and Sputolysin (dithiothreitol) diluted with PBS and used to liquify respiratory samples. Species analysis revealed B contaminans in surgical, respiratory, and reagent samples. RAPD typing and WGS confirmed clonality, suggesting that PBS was a source of extrinsic contamination.

CONCLUSIONS

This investigation underscores the role of multidisciplinary collaboration, robust electronic health information systems, and microbial genomic tools in infection prevention and control, ensuring timely interventions and patient safety.