Background and Aim: The new Coronavirus Disease 2019 (COVID-19) outbreak initiated from China in late December 2019, has posed a great global health threat. Since patients with high blood pressure, diabetes, and cardiovascular diseases are at high risk of COVID-19, this study aims to investigate the prevalence, severity, clinical manifestations, and mortality rate in COVID-19 patients with underlying diseases compared to those without underlying diseases. Methods & Materials: This study was performed on 1408 patients with COVID-19 admitted to Golestan, Hajar, Khanevadeh and Besat hospitals in Tehran, Iran. Required data including disease prevalence, severity, clinical manifestations and mortality rate in patients with and without underlying diseases were collected and then analyzed using statistical tests in SPSS software, considering a significance level of P<0.05. Ethical Considerations: This study was approved by the AJA University of Medical Sciences (Code: IR.AJAUMS.REC.1399.091). Ethical principles have been observed in accordance with the guidelines of the National Ethics Committee and the COPE regulations. Results: Patients were 912 men (64.8%) and 496 women (35.2%) aged 18-98 years (Mean age= 57.8 years). Results reported that 27% of patients were intubated and 21.9% were died. Blood oxygen level in 53.7% of patients was less than 93 mg/dL; 36.1% had a history of hypertension, 24.1% had a history of diabetes, and 21.7% had a history of cardiovascular disease. Conclusion: The severity, clinical manifestations, and mortality rate of COVID-19 patients with cardiovascular disease, diabetes and hypertension are significantly different compared to those without underlying diseases.

Background and Aim: Since late 2019, with the emergence of a new type of coronavirus that causes a new respiratory disease called COVID-19, there have been many concerns about the spread of this disease and how to deal with it. Due to the ability of the virus to be transmitted rapidly, diagnosing the infected individuals in the early stages for isolating them is critical. This study aims to evaluate the reliability of Computed Tomography (CT) scan in diagnosing COVID-19. Methods & Materials: Participants were 212 patients admitted to hospital with confirmed diagnosis of COVID-19. Demographic information, medical history, symptoms, and the chest CT scan results were collected and analyzed. Finally, the power of CT scans in the diagnosis of this disease was compared with the Real-Time Polymerase Chain Reaction (RT-PCR) molecular test. Ethical Considerations: This study received ethical approval from the ethics committee of AJA University of Medical Sciences (Code: IR.AJAUMS.REC.1399.091). Results: The sensitivity of CT scan in the diagnosis of COVID-19 was relatively high, but its false-positive results were also high. Conclusion: CT scan is a relatively sensitive method for diagnosing COVID-19, but caution should be made due to its high false-positive results which can lead to increased financial burden on the health system.