Effusion fluid cytology and COVID-19 infection.

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which is responsible for coronavirus disease 2019 (COVID-19), is known to cause severe respiratory infections with occasional accompanying pleural effusion (PE), pericardial effusion (PCE), or peritoneal effusion (PTE). The effect of COVID-19 on effusion cytology is not yet known. This study aimed to examine the cytomorphologic features and workup of effusion fluids in patients with active COVID-19 infection versus those in recovery. METHODS: PE (n = 15), PCE (n = 1), and PTE samples (n = 20) from hospitalized patients with a SARS-CoV-2 infection (from June 1, 2020, to December 30, 2020) were reviewed. Effusion fluids with metastatic carcinoma were excluded. Differential cell counts, cytomorphology, and relevant immunostains for effusion fluids were retrospectively evaluated and compared between patients with active infection (positive on a SARS-CoV-2 nucleic acid amplification test [NAAT] within 2 months; n = 23) and those in the recovery phase from COVID-19 (negative on a SARS-CoV-2 NAAT for >2 months; n = 13). RESULTS: The cytology diagnoses were negative for malignancy (n = 31), atypical (n = 4), and suspicious for malignancy (n = 1). Active infection cases showed more atypical mesothelial cells than recovery cases (P < .05); some had enlarged nuclei, prominent nucleoli, occasional multinucleation, and bizarre nuclei. Immunostains were performed more often in active infection cases than recovery cases (47.8% vs 7.7%; P < .05). Differential cell counts (available for 28 cases) showed no significant differences between the active infection and recovery groups. CONCLUSIONS: This study found atypical and bizarre mesothelial cells more often in effusions of cases with active COVID-19 infection in comparison with patients in recovery. It is important for cytopathologists to become familiar with the cytomorphologic effects of SARS-CoV-2 on effusion cytology so that these cases can be properly triaged.

Lessons Learned From an Anatomic Pathology Department in a Large Academic Medical Center at the Epicenter of COVID-19.

Many state-wide, city-wide, and hospital-wide changes have been implemented due to the ongoing COVID-19 crisis. We describe lessons learned in an anatomic pathology division at a tertiary care center during the peak of the COVID-19 pandemic in the hopes that knowledge of our experiences can benefit other pathology departments as they encounter this pandemic. Five categories that are critical in strategic planning for the COVID-19 pandemic are discussed: workload, departmental policy revisions, impact on faculty, workforce staffing, and impact on educational programs, including residency and fellowship training. Although the volume of COVID-19 testing had grown placing increased demands on the clinical pathology laboratory, the volume of anatomic pathology cases had declined during the COVID-19 peak. Lessons learned were widespread including changes in the anatomic pathology workflow due to declining surgical and cytologic case volumes and increases in autopsy requests. Modifications were required in gross room policies, levels of personal protective equipment, and workforce. Travel and meeting policies were impacted. Adaptations to residency and fellowship programs were vast and included innovations in didactic and interactive education. We must learn from our experiences thus far in order to move forward, and we hope that our experiences in an anatomic pathology department in the epicenter of the COVID-19 pandemic can help other pathology departments across the country.