Risk Factors for Mortality in Stable Kidney Transplant Patients Infected by SARS-CoV-2 in the South of Spain.

Background: The coronavirus disease 2019 (COVID-19) pandemic has especially affected kidney transplant (KT) recipients, who are more vulnerable than the general population because of their immunosuppressive status and added comorbidities. The purpose of this study was to determine risk factors related to infection and mortality from COVID-19 in KT recipients.

Methods: The study included 113 stable KT recipients who had polymerase chain reaction-confirmed COVID-19 infection between March 2020 and February 2021, from a total of 2150 KT recipients. Outcomes related to patient survival were analyzed.

Results: The mean (standard deviation) age of the patients was 56 (14) years; 62% (n = 70) were men. The median time between KT and infection was 88 months (interquartile range, 39-155 months); 90% (n = 102) were on tacrolimus therapy and 81% (n = 92) on mycophenolate mofetil. The clinical presentation was pneumonia (n = 57; 51%), fever (n = 61; 54%), cough (n = 62; 55%), dyspnea (n = 43; 38%), lymphopenia (n = 57; 50%), and gastrointestinal symptoms (n = 28; 25%). A total of 21% (n = 24) required intubation and intensive care unit admission, and 27 patients (25%) were asymptomatic. A total of 9% (n = 10) received hydroxychloroquine therapy plus azithromycin, 11% (n = 12) tocilizumab, 3.7% (n = 4) lopinavir/ritonavir, 49% (n = 55) steroids, 0.9% (n = 1) remdesivir, and 9.3% (n = 11) convalescent plasma. Immunosuppression was reduced in all symptomatic patients. Nineteen patients (17%) died. Cox univariate analysis showed that the factors significantly associated with death were patient age, presence of pneumonia or lymphopenia, and elevated C-reactive protein on admission.

Conclusions: Mortality in KT recipients with COVID-19 is very high, more than for the general population. Risk factors are patient age, presence of pneumonia or lymphopenia, and a higher C-reactive protein level at the time of diagnosis.