Background: There is a great need to make a rapid differential clinical diagnosis of COVID-19 among respiratory disease patients and determining the prevalence rate of these diseases among the COVID-19 population. Method: Approximately 522 patients with allergic rhinitis, asthma, COPD, and COVID-19 were analyzed for demographic and clinical features. Radiological features were analyzed only for COVID-19 patients. Results: COPD and asthma were more common among COVID-19 patients than allergic rhinitis. All chest CT scans of COVID-19 patients showed bilateral ground-glass opacity. Fever, dry cough, diarrhea, loss of sense of smell and taste, shortness of breath, and blue lips were significantly higher in all COVID-19 patients compared to COPD, asthma, and allergic rhinitis patients. Conclusion: The presence of clinical symptoms such as fever, dry cough, diarrhea, loss of sense of smell and taste, shortness of breath, and blue lips in COVID-19 patients, can be used for differential diagnosis between COVID-19 patients and other respiratory diseases. Then, the diagnosis can be confirmed by chest CT scan for COVID-19 patients without the need for a nasopharyngeal swab or PCR test, especially in epidemic countries. Allergic rhinitis patients are the least exposed to COVID-19 infection among other respiratory disease patients.

Objectives: The treatment of COVID-19 infection remains a challenge because till now, there is no approved therapy for it. This study aimed to estimate the difference in the therapeutic efficacy and safety between remdesivir as monotherapy and its use in combination with lopinavir/ritonavir provided with standard supportive care. Methods: This is a prospective randomized cohort study included 1043 adult patients with confirmed moderate and severe COVID-19 infection. Treatment of all patients followed Egyptian Ministry of Health COVID-19 protocol as the first group received IV remdesivir 200 mg on day 1, followed by 100 mg once daily, for 5 days while the second group received lopinavir/ritonavir 400/100 mg twice daily, for 5 days with the same remdesivir regimen in the first group. All laboratory and clinical parameters were assessed before and after treatment duration. Results: There was no significant difference related to improvement parameters such as laboratory data and improvement time between the two groups. On the other hand, hepatotoxicity of the second group (combination) was significantly higher compared with that of the first one. The elevation on liver enzymes was affected by the severity of the disease, the severe cases showed a high enzyme elevation rate. Conclusion: Remdesivir as monotherapy and its use in combination with lopinavir/ritonavir is effective in the management of moderate COVID 19 subjects than severe cases. The combination of remdesivir with lopinavir/ritonavir is not recommended due to the increased hepatotoxicity effect.