All patients consulting at the emergency department of our hospital from the 1st of March till the 14th of May, with symptoms suggestive of COVID-19 disease that required hospital admission and for which laboratory diagnosis was performed in our institution were retrospectively included in a database. In all patients a RT-PCR test on nasopharyngeal/throat swab was performed at the time of admission. If the initial nasopharyngeal swab was found to be negative, a second nasopharyngeal and additional anal swab were analyzed. If still negative, a bronchoalveolar lavage (BAL) was performed. Patients with repetitive negative molecular testing for SARS-CoV-2 but high clinical, epidemiological and/or radiological suspicion of COVID-19 disease were subjected to serological testing using COVID-19 IgG/IgM rapid test (Prima Professional®). Among this retrospective cohort of hospitalized patients clinically treated for COVID-19 disease, we calculated the number of patients that ultimately had a RT-PCR confirmed diagnosis. As such, an estimation of the added diagnostic value of SARS-CoV-2 serology in this cohort could be calculated.