Tehran University of Medical Sciences Acta Medica Iranica 0044-6025 61 6 2023 10 04 375 377 Jalal Karimi Department of Infectious Diseases, School of Medicine, Fasa University of Medical Sciences, Fasa, Iran. Zahra Pourmontaseri Department of Infectious Diseases, School of Medicine, Fasa University of Medical Sciences, Fasa, Iran Hojatolah Najafi Department of Health in Disasters and Emergencies, School of Management and Medical Informatics, Shiraz University of Medical Sciences, Shiraz, Iran Milad Ahmadi Marzaleh Department of Health in Disasters and Emergencies, School of Management and Medical Informatics, Shiraz University of Medical Sciences, Shiraz, Iran. Zahra Rahimi Asl Department of Medical Education, Fasa University of Medical Sciences, Fasa, Iran 2021 05 23 2023 01 27 Introduction: The COVID-19 has recently become pandemic. Early diagnosis and the transmission chain cutting off are critical keys to control this disease and stop its spread. In this case report, the significance of proper and on-time diagnosis is discussed. Misdiagnosis of COVID-19 may lead to delay in early diagnosis of the disease. Case Presentation: A 78-year-old man with chief complaint of dark stool and constipation was admitted. Based on the preliminary complaints of the patient, the emergency medical specialist transferred him to the internal caregiving service, but according to radiological findings and his positive Real time PCR test, COVID-19 was final diagnosis. Conclusion: Healthcare planners and policymakers should prepare precise clinical guidelines that are compatible with domestic conditions of the country to improve the ability of health care providers for diagnosing patients with COVID-19 to promote controlling this condition. https://acta.tums.ac.ir/index.php/acta/article/view/9420 https://acta.tums.ac.ir/index.php/acta/article/download/9420/5803