*4.3. Secondary E*ff*ects of COVID-19 on SOT Patients*

In transplantation medicine, COVID-19 has had a noticeable negative influence both on the ambulatory and the hospitalized patients with SOT, with strong psychological effects and increased need for psychological support from transplant physicians, transplant psychiatrists and psychologists, in addition to the somatic effects. This negative influence may become even more obvious as time passes, and the missed follow-up appointments may potentially influence the course of the disease in the coming months. The total impact in this area will only be fully understood in the near future when studies address these issues.

In summary, although further research is urgently needed to give a clearer picture of the impact of SARS-CoV-2 and COVID-19 on the SOT community, the currently available limited data suggest a reduced immediate impact of COVID-19 in respect to severity of disease, most likely due to "protective" immunosuppression. Based on this preliminary observation, we expect a milder disease severity and probably a better outcome in patients with SOT in a population, because they are typically well aware of the risks of viral (and other) infections and thus practice prevention strategies more rigorously, due to knowledge they have acquired prior to the current coronavirus pandemic. In the absence of definitive medical treatment protocols, many treatments have been suggested. Although it is too early for results of large clinical trials, generally in the above-described case reports with COVID-19 stage IIA or IIB, MMF initially is stopped, tacrolimus is reduced, methylprednisolone iv is started, and empiric broad-spectrum antibiotics are given. Hydroxochloroquine or lopinavir-ritonavir/darunavir-cobicistat was given as off-label therapy in some patients. Intravenous gammaglobulins are an alternative treatment for patients at risk of infection-triggered rejection, in whom the immunosuppressive treatment cannot be escalated due to increased drug-related adverse events or fear of increased viral replication.

Whilst more definitive and clinically proven treatments are awaited, the above described treatments can be helpful in the short term and may be reassuring for the SOT community.

**Author Contributions:** All authors were equally involved in planning the study, collecting the information and drafting the manuscript and tables. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research received no external funding.

**Acknowledgments:** We would like to thank Rupert Taylor for the English editing help.

**Conflicts of Interest:** The authors declare no conflict of interest.
