[Retrospective clinical-causal evaluation of a positive PCR for SARS-CoV-2 in hospitalised patients across the age spectrum in a primary care hospital].

Introduction: It is often discussed that a positive PCR for SARS-CoV-2 in hospitalized patients may not be causally linked to the hospital stay, but no scientific data are available from Germany. Therefore, we analyzed to what extent a positive PCR test could be assessed as causal or secondary to admission according to clinical criteria in a tertiary care hospital of the first 4 months of 2022.

Methods: SARS-CoV-2-positive patients of RoMed-Klinikum Rosenheim/Bavaria from 01/01/2022 to 30/04/2022 were included. Patients were divided into a group with COVID-19 as direct reason for admission (CAW), and a group, in which this did not apply according to a comprehensive clinical assessment (nCAW). Patients with no clear allocation to these groups were counted separately. Categorization was based on a multilevel procedure and performed by an internist experienced in COVD-19 (M.H.). It included all available clinical, radiological, and laboratory findings as well as treatment decisions.

Results: 647 cases were included (age 10 days to 101 years, median 68 years; 49.5% women), including 13 patients in two admissions with positive PCR. 45.3% (n=293) were attributable to the group with COVID as the reason for admission, 48.8% (n=316) were not, no clear decision could be made in 35 patients, 3 patients were transferred from other clinics for isolation. In infants (up to 1 year), a positive PCR test was more frequently categorized as causative than in older patients. Leading symptoms of classification were found to be fatigue/fatigue, fever/chills, and cough on admission. Febrile convulsions accounted for the reason for admission in 10 cases of children (age 1.1-7.6 years). Length of stay did not differ significantly between groups (median (quartiles) 5 (2; 10) days for CAW, 5 (2; 12) for nCAW), nor did in-hospital mortality and median age of deceased or survivors.

Discussion: A retrospective analysis of all clinical data revealed that positive SARS-CoV-2 PCR played a major and - according to clinical criteria - causative role for admission and hospitalization in nearly 50% of cases, whereas it was an incidental finding in just under 50%. These results confirm data from other countries and demonstrate that the role of a positive SARS-CoV-2 PCR test for hospitalization can only be answered by a comprehensive and elaborate analysis of individual data.