Investigation of a Candida guilliermondii Pseudo-outbreak Reveals a Novel Source of Laboratory Contamination.

was isolated from sterile specimens with increasing frequency over a several-month period despite a paucity of clinical evidence suggesting true infections. However, a health care-associated outbreak was strongly considered due to growth patterns in the microbiology laboratory that were more consistent with true infection than environmental contamination. Therefore, an extensive investigation was performed to identify its cause.