Diagnostic groups and short-term outcomes in suspected COVID-19 cases treated in an emergency department.

OBJECTIVES: The primary objective was to describe the clinical characteristics and 30-day mortality rates in emergency department patients with coronavirus disease 2019 (COVID-19) in different diagnostic groupings.
MATERIAL AND METHODS: Secondary analysis of the COVID-19 registry compiled by the emergency department of Hospital Clínico San Carlos in Madrid, Spain. We selected suspected COVID-19 cases treated in the emergency department between February 28 and March 31, 2020. The cases were grouped as follows: 1) suspected, no polymerase chain reaction (PCR) test (S/no-PCR); 2) suspected, negative PCR (S/PCR-); 3) suspected, positive PCR (S/PCR+); 4) highly suspected, no PCR, or negative PCR (HS/no or PCR-); and 5) highly suspected, positive PCR (HS/PCR+). We collected clinical, radiologic, and microbiologic data related to the emergency visit. The main outcome was 30-day all-cause mortality. Secondary outcomes were hospitalization and clinical severity of the episode.
RESULTS: A total of 1993 cases (90.9%) were included as follows: S/no-PCR, 17.2%; S/PCR-, 11.4%; S/PCR+, 22.1%; HS/no PCR or PCR-, 11.7%; and HS/PCR+, 37.6%. Short-term outcomes differed significantly in the different groups according to demographic characteristics; comorbidity and clinical, radiographic, analytical, and therapeutic variables. Thirty-day mortality was 11.5% (56.5% in hospitalized cases and 19.6% in cases classified as severe). The 2 HS categories and the S/PCR+ category had a greater adjusted risk for 30-day mortality and for having a clinically severe episode during hospitalization in comparison with S/PCR- cases. Only the 2 HS categories showed greater risk for hospitalization than the S/PCR- cases.
CONCLUSION: COVID-19 diagnostic groups differ according to clinical and laboratory characteristics, and the differences are associated with the 30-day prognosis.