Materials and methods
One hundred fifty-five Covid-19 patients were included in this study. A confirmed case with COVID-19 was defined as a positive result to real-time reverse-transcriptase polymerase-chain-reaction (RT-PCR) assay for nasal and pharyngeal swab specimens [15]. Written informed consent was obtained from all the patients that participated in this study, and the local ethics committee of Bulent Ecevit University, Faculty of Medicine approved the study. Patients with Covid-19 were grouped according to the severity of the disease. Clinical characteristics of patients are shown in Table 1. COVID-19 severity is classified as follows; Mild type: Outpatients, the clinical symptoms are mild, with no abnormal radiological findings, Moderate type: Hospitalized for persistent fever or pneumonia or mild respiratory distress or present pneumonia on chest CT, Severe type: The disease is classified as severe if one of the following conditions is met: