Clinical Aspects of COVID-19 in Patients with Solid Organ Transplantation: A Systematic Review

Background Coronavirus disease 19 (COVID-19), is an infectious disease caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). This virus is causing a pandemic with more than 40 million proven infections worldwide. Aim In order to summarize the clinical characteristics of coronavirus disease-19 (COVID-19) in solid organ transplant (SOT) recipients, we conducted a systematic review of studies on COVID-19 in these patients. Methods The literature search was conducted repeatedly between March 16th and May 1st, 2020. We searched original papers, observational studies, case reports, and meta-analyses published between December 2019 and May 1st 2020 using two databases (PubMed, Google Scholar) with the search terms: [transplant OR immune suppression] AND [COVID-19 OR SARS-CoV-2]. Further inclusion criteria were publications in English, French, German and Italian and reference to humans. We also searched the reference lists of the studies encountered. Studies on non-solid organ transplantation were excluded, as well as animal and in vitro studies. Results From an initial search 37 potential articles were retrieved, of which 15 were excluded after full-text screening (not being case reports or case series), leaving 22 studies for inclusion. No further studies were identified from the bibliographies of the retrieved articles. Conclusion Between March 16th and May 1st, 2020, only 49 SOT recipients have been described in literature. Most of these patients survived, and had a fairly mild disease course. Based on the limited research data, no firm conclusions can be made concerning specific treatment of SOT recipients, but the current evidence suggests that immunosuppression, especially the calcineurin inhibitors, decreases the incidence and improves the outcome of symptomatic COVID-19, by preventing hyperinflammation (cytokine storm). Evidence based guidelines are urgently needed for this particular group of patients