ABSTRACT
Background: There is still a lack of knowledge on host immune response and risk of reinfection, particularly in special groups, such as liver transplant recipients. Immunosuppressive agents are known to interfere with T- and/or B-lymphocytes, which are required to mount an adequate serologic response. Therefore, we aim to investigate the antibody response to SARS-CoV-2 in liver transplant (LT) recipients after COVID-19. Methods: We conducted a prospective multicenter casecontrol study analyzing antibodies against the nucleocapsidprotein and spike protein of SARS-CoV-2 in LT recipients with confirmed SARS-CoV-2 infection (COVID-LT) compared to immunocompetent patients (COVID-immunocompetent) and liver transplant patients without COVID-19 symptoms (non-COVID LT). Serum samples were collected from all the participants included in the study. In the COVID-LT cohort, as well as in the COVID-immunocompetent cohort, the samples were drawn between 4-8 weeks after the detection of the SARS-CoV-2 infection. Results: Overall, 35 LT recipients were included in the COVID-LT cohort. Male gender was most prevalent (25 recipients, 71.4%) and mean age was 56.7±13.9 years. 35 and 70 subjects fulfilling the matching criteria were assigned to the COVID-immunocompetent and non-COVID LT cohort, respectively. We showed that LT recipients, despite the use of immunosuppressive drugs and less symptoms, mounted a detectable anti-nucleocapsid antibody titer in 80% of the cases, although the level was significantly lower in comparison to the level detected in the COVID-immunocompetent cohort (3.73 vs. 7.36, p<0.001). When analyzing the anti-spike-protein antibody response, no difference in positivity rates was found between the COVIDLT and the COVID-immunocompetent cohorts (97.1% vs. 100%, p=0.314). Considering the non-COVID LT group, we found that cross-reactivity with other coronavirus species is irrelevant for these assays (only one positivity for the antinucleocapsid and two for the anti-spike). Conclusion: Our findings suggest that the humoral response of LT recipients is only slightly lower than expected compared with that of COVID-19 immunocompetent controls. Anti-nucleocapsid antibodies, although specific for SARS-CoV-2 when tested alone, may erroneously lead to an underestimation of the immune response in this population. Testing for anti-spike antibodies adds sensitivity. Altogether, routine antibody testing against separate SARS-CoV-2 antigens shows that LT patients are capable of mounting an adequate antibody response against SARS-CoV-2.
ABSTRACT
Background: In December 2019, a new contagious disease, named COVID-19 caused by a novel coronavirus (SARSCov- 2) emerged in Wuhan City, China Since February 2020 this disease has also spread to Italy Bergamo, where one of the most active liver transplant (LT) Italian center is located, has been one of the most affected cities by COVID-19 This study aimed to evaluate the impact of COVID-19 in liver transplant patients Methods: From April 1st, 2020, to May 15th, 2020, 660 adult liver transplant recipients were contacted by phone by the medical staff of the Transplant Center at the ASST-Papa Giovanni XXIII-Bergamo The presence of COVID-19 symptoms (fever, cough, dyspnea, asthenia, dysgeusia, anosmia, gastrointestinal complaints and/or myalgia) and contact at risk were investigated Results of RX chest, SARS-Cov-2 nose-swab and hospitalizations, when occurred, were recorded in symptomatic patients Results: Seventy-seven patients (11 7%) reported symptoms related to SARS-Cov-2 infection;patients were primarily males (72 7%), with a median age of 62 9 years (IQR 57 1-69 0) and a median time from LT of 73 6 months (IQR 36 5-135 8) A chest x-rays was performed in 25/77 symptomatic patients (32 5%) and in 17/25 (68 0%) an interstitial pneumonia was found;swabs were performed in 21/77 patients (27 3%) and 17 of them (81 0%) resulted positive Among symptomatic patients, all reported at least two symptoms and in 14 (18 2%) five symptoms were present. Three patients (3.9%) had been hospitalized for transplant-related reasons and 11 patients needed hospitalization because of COVID-19 (14 9%) All hospitalized patients were treated with antibiotics;high dose steroids were added to 8 patients and antiviral therapy (lopinavir/ritonavir) to 4 patients Nine patients (11 7%) needed oxygen therapy One patient died for non-COVID-19 related condition, 2 patients died for COVID-19 (2/76;2 6%) Mortality in hospitalized patients was 21 4% (3/14), COVIDrelated mortality-rate was 15 4% (2/13) and both patients died within one month after LT Conclusion: COVID-19 can affect liver transplant patients, however, in our experience, both the need for hospitalization and deaths do not exceed those observed among the general population.