Tehran University of Medical Sciences Acta Medica Iranica 0044-6025 59 1 2021 02 14 4 14 Masoumeh Mohamadi Department of Dermatology, Rasool Akram Medical Complex, Iran University of Medical Sciences, Tehran, Iran Nima Fattahi Non-Communicable Diseases Research Center, Endocrinology and Metabolism Population Sciences Institute, Tehran University of Medical Sciences, Tehran, Iran. Azadeh Goodarzi Department of Dermatology, Rasul Akram Hospital, Iran University of Medical Sciences (IUMS), Tehran, Iran Mahtab Alizadeh-Khoei Department of Clinical Gerontology & Geriatric, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran. AND Ziaeian Hospital, Tehran University of Medical Sciences, Tehran, Iran. Shahnaz Miri Department of Neurology, MedStar Georgetown University Medical Center, Washington, D.C., United States Hamidreza Hekmat Department of Cardiology, Ziaeian Hospital, Tehran University of Medical Sciences, Tehran, Iran. Mohammad Bodaghabadi Department of Geriatric Medicine, Ziaeian Hospital, Tehran University of Medical Sciences, Tehran, Iran Farahnaz Nikkhah Department of Rasool Akram Medical Complex Clinical Research Development Center (RCRDC), Iran University of Medical Sciences, Tehran, Iran. 2020 07 10 2020 10 23 In the Coronavirus disease 2019 (COVID-19) pandemic, underlying diseases such as cardiovascular disease, respiratory illness, liver and kidney disease or malignancies, have a critical prognostic role for these patients. Due to the increased risk of mortality in patients with established or new-onset comorbidities, we decided to conduct a study to further investigate the possible comorbidities and treatment recommendations of COVID-19. All articles published by March 25, 2020, on the new coronavirus infection were reviewed and for cutaneous manifestation as a new emerging concern, by April 25, 2020. ScienceDirect, Google Scholar, Scopus, PubMed databases were searched, and keywords such as "COVID-19", "2019-nCoV", "Coronavirus2019", "SARS-CoV-2”, and "comorbidity" have been used. The most important comorbidity in elderly patients with confirmedCOVID-19 was cardiovascular disease, followed by diabetes and chronic respiratory disease, respectively, and on the other hand, COVID-19 itself could cause acute heart, lung, liver, kidney, and skin disease. Also, the prevalence of underlying diseases in dead patients or patients with severe COVID-19 is higher than the others. Considering treatment, drug interactions, and careful drug adjustment based on hepatic and renal metabolism are essential. The results of this study showed that the mortality rate and ICU admission in people with the underlying disease is higher than in other people. Also, we must pay attention to the possible multi-organ damages and comorbidities for the protection and successful treatment of COVID-19. There are some comorbidities like primary cutaneous manifestations that may have diagnostic or prognostic values in the COVID-19 course. https://acta.tums.ac.ir/index.php/acta/article/view/8618