Archivio Italiano di Urologia e Andrologia 2021; 93, 4 460 ORIGINAL PAPER No conflict of interest declared. pelvic ganglia to smooth muscles and the endothelial cells of the corpora cavernosa (4). Low testosterone levels are associated with decreased libido, ED, decreased energy, depressive symptoms, and fatigue (5). Changes in testos- terone levels after COVID-19 may not only increase the severity of ED but also cause ED alone (6). The relationship between COVID-19 and testosterone is based on contracting the disease, the severity of the dis- ease and progression of the disease. COVID-19 makes use of Transmembrane protease serine 2 (TMPRSS2) to pene- trate into the host cell and androgen receptors are tran- scription supportive for TMPRSS2. The higher the testos- terone level, the easier it is for COVID-19 to penetrate into the host via this mechanism (7). Besides, TMPRSS2 is up-regulated in prostate cancer where it supports tumor progression, thus these patients may have a higher risk of SARS-CoV-2 infection. TMPRSS2 inhibitors may be useful for the treatment or prevention of COVID-19 (8). On the contrary, some other studies have reported that low testosterone levels are associated with acute res- piratory distress syndrome (ARDS) by increasing proin- flammatory cytokines and they intensify COVID-19 infection in elderly men (9). ED which is caused by COVID-19 appears to be associat- ed with both vascular endothelial damage and reduction in testosterone level. Even though the studies in the last year mostly focused on primary disease due to the pan- demic, In some studies, COVID-19 and its effects on sex- ual life have begun to be revealed and suggestions are made in terms of sexual health, especially through andrology associations (10), but the results on effects of COVID-19 infection on the male reproductive system are currently insufficient as they are based on a small number of patients and therefore are often contradictory (11). Our study aimed to figure out the factors which may play a role in the development of ED in our patients with COVID-19 and the effect of testosterone level on the prognosis of COVID-19. MATERIALS AND METHODS Study design and patients Our study has been designed after being approved by the Republic of Turkey Ministry of Health and the local ethics committee (Ethical committe approval number: 1303/27.01.2021) and 210 patients who were admitted Objective: We aimed to investigate the rela- tionship between COVID-19 and Erectile Dysfunction (ED) and the effect of serum testosterone level on the disease prognosis. Methods: Between April-December 2020, 70 patients who were admitted with a complaint of ED after having COVID-19 and whose serum testosterone level was checked for varicocele, pre- mature ejaculation, and infertility reasons before COVID-19. The patients filled the International Index of Erectile Function (IIEF-5) and their testosterone level was checked. The question- naire was arranged to assess the first month before COVID-19 and after COVID-19. Testosterone levels of the patients before and after COVID-19 were compared. The relationship between testosterone levels and hospitalization in the intensive care was evaluated. Results: It was revealed that testosterone levels and IIEF-5 scores after COVID-19 in all patients were statisticaly and significantly different compared to the period before COVID-19 (p < 0.05). Testosterone levels of patients in need of intensive care were significantly higher than those without any need of intensive care (p < 0.05). Conclusions: Our study has presented that COVID-19 may cause ED and high testosterone levels increase the rate of hospitalization in the intensive care by intensifying the disease. KEY WORDS: COVID-19; Erectile dysfunction; Testosterone. Submitted 18 September 2021; Accepted 9 October 2021 INTRODUCTION The global coronavirus disease (COVID-19) results in a cytokine storm that leads to the development of micro- thrombosis and diffuse intravascular coagulation (DIC) (1). Despite the fact that lungs are the organs which are pri- marily targeted in cytokine storm, the cardiovascular sys- tem is also affected. The autopsies which were performed showed that there were signs of endothelial damage, pul- monary embolism, bleeding at multiple levels including alveolar, microangiopathy, and vascular dysfunctions in the form of vasculitis (2). The relationship between Erectile Dysfunction (ED) and COVID-19 develops due to vasculogenic and hormonal causes which were caused by the primary disease. The vasculogenic damage and ED are also seen as predictors of a cardiovascular pathology which may be observed in patients in the future (3). Testosterone, which is the most important hormone in male erection, modulates almost every component involved in erectile function, from the Erectile dysfunction and testosterone levels prior to COVID-19 disease: What is the relationship? Kadir Karkin, Ergün Alma Department of Urology, Health Sciences University, Adana City Training and Research Hospital, Adana, Turkey. DOI: 10.4081/aiua.2021.4.460 Summary