Seven-year retrospective review of medical microbiologist consultations on cytology specimens at an academic medical center.

Objective: Cytology samples can harbor clinically significant microorganisms; however, cytopathologists can be challenged by the interpretation of special stains and the description or classification of microorganisms. This study aimed to highlight the value of medical microbiologist consultations on cytology specimens.

Methods: This quality assurance project retrospectively reviewed all medical microbiologist consultations on cytology specimens from 2018 to 2024. Special stains used, consultation findings, associated clinical microbiology laboratory studies, and the clinical significance of identified microorganisms were extracted from cytology reports and the electronic medical record.

Results: Medical microbiologist consultations were requested on 152 cytology samples from 139 patients. Thoracic sources comprised most cases (110/152, 72%). Clinically significant microorganisms were identified in 30% (45/152), of which most were fungi. The medical microbiologist confirmed artifacts or mimics in 24% (36/152). The microbiologist assisted cytopathologists in the care of 15 patients with clinically significant pathogens but for whom relevant clinical microbiology laboratory studies were negative or not performed.

Conclusions: Medical microbiologists and the clinical microbiology laboratory are important resources for the diagnosis of infectious diseases in cytology specimens. This project uniquely documents the consultative and collaborative relationship between cytopathologists and medical microbiologists at a major academic medical center and highlights its positive impact on patient care.