SARS-CoV-2 vaccine alleviates disease burden and severity in liver transplant recipients even with low antibody titers.

BACKGROUND AND AIMS: We retrospectively assessed the clinical Pfizer's mRNA SARS-CoV-2 BNT162b2 vaccination outcomes and the serologic impact on liver transplant (LT) recipients. PATIENTS AND METHODS: One hundred and sixty-seven LT cases followed between March 1, 2020 and September 25, 2021, and were stratified into two groups: (1) 37 LT recipients after SARS-CoV-2 infection before vaccine era and (2) 130 LT recipients vaccinated with 2 doses without earlier SARS-CoV-2 exposure. Serum SARS-CoV-2 spike immunoglobulins (anti-S) were assessed 7 days following vaccination (Liaison assay). RESULTS: In addition to the 37 nonvaccinated cases (22.2% of total group) who experienced SARS-CoV-2 infection (34 symptomatic and 3 asymptomatic), another 8 vaccinated symptomatic recipients (4.8%) were infected (5 from the third and three from the fourth waves). Three of the 45 infected cases died (6.7%) before the vaccine program. Vaccinated group: of the 130 LT vaccinated recipients, 8 (6.2%) got infected postvaccination (added to the infected group) and were defined as clinical vaccine failure; 38 (29.2%) were serological vaccine failure (total failure 35.4%), and 64.6% cases were serological vaccine responders (anti-S≥19 AU/mL). Longer post-LT interval and lower consumption of immunosuppressants (steroids, FK506, and mycophenolate mofetil) correlated with favorable SARS-CoV-2 vaccine response. Mammalian target of rapamycin inhibitors improved vaccine outcomes associated with lower FK506 dosages and serum levels. Patients with anti-S levels <100 AU/mL risked losing serologic response or being infected with SARS-CoV-2. A booster dose achieved an effective serologic response in a third of failures and most responders, securing better and possibly longer protection. CONCLUSION: Pfizer's BNT162b2 vaccine seems to lessen SARS-CoV-2 morbidity and mortality of LT recipients even with weak serological immunogenicity. Switching mycophenolate mofetil to mammalian target of rapamycin inhibitors might be effective before boosters in vaccine failure cases. A booster vaccine should be considered for nonresponders and low-responders after the second dose.

Advanced Liver Fibrosis Correlates With Impaired Efficacy of Pfizer-BioNTech COVID-19 Vaccine in Medical Employees.

The Pfizer-BioNTech coronavirus disease 2019 (COVID-19) vaccine has been offered to nonallergic ≥16-year-old Israeli adults since December 19, 2020. Data regarding factors associated with vaccine ineffectiveness are limited. The aim of this study is to assess the impact of hepatic fibrosis on the efficacy of the BioNTech vaccine. Serum severe acute respiratory syndrome coronavirus 2 spike immunoglobulins (S IgG) obtained at least 7 days following vaccination completion was correlated with the prevaccine calculated Fibrosis-4 (FIB-4) score among 719 employees in the Hadassah Medical Center, Jerusalem. Positive vaccine response (S IgG levels ≥ 19 AU/mL) was found in 708 of 719 individuals (98.5%). Vaccine failure (S IgG levels < 19) was found in 11 (1.5%); of these, 7 were immunosuppressed. Mean FIB-4 available in 501 of 708 vaccine responders was 1.13 ± 0.66, mean age 51.4 ± 12.4 years (29.3% males), and mean S IgG titers 239.7 ± 86.1 AU/mL. Similar to the general population, 70.5% had normal FIB-4 (<1.3), 26.8% undetermined FIB-4 (1.3-2.67), and 2.7% advanced FIB-4 (>2.67). When divided into response subgroups, 158 of 501 individuals (30.1%) with IgG titers 19-100 AU/mL had a mean FIB-4 of 1.48 ± 0.82; 198 (39.5%) with IgG titers 101-200 AU/mL had mean FIB-4 of 1.22 ± 0.76; 83 (16.6%) with titers 201-300 AU/mL had mean FIB-4 of 1.04 ± 0.48; 38 (7.6%) individuals with IgG titers 301-400 AU/ml had a mean FIB-4 of 1.08 ± 0.63; and 121 (24.2%) with IgG titers >400 AU/mL had mean FIB-4 of 1.18 ± 0.87. Increased FIB-4, age, and male gender significantly correlated with lower postvaccine IgG titers (P < 0.001). FIB-4 results were confirmed using FibroScan data displaying advanced fibrosis impact on weakened COVID-19 vaccine response. Conclusion: Immune suppression, older age, male gender, and advanced chronic liver disease are risk factors for lower vaccine response. The FIB-4 provides a simple tool to prioritize candidates for third-dose vaccine booster.

Impact of tozinameran (BNT162b2) mRNA vaccine on kidney transplant and chronic dialysis patients: 3-5 months follow-up.

BACKGROUND: Determining the humoral immunogenicity of tozinameran (BNT162b2) in patients requiring chronic renal replacement therapy, and its impact on COVID-19 morbidity several months after vaccination, may guide risk assessment and changes in vaccination policy. METHODS: In a prospective post-vaccination cohort study with up to 5 months follow-up we studied outpatient dialysis and kidney transplant patients and respective healthcare teams. Outcomes were anti S1/S2 antibody responses to vaccine or infection, and infection rate during follow-up. RESULTS: One hundred seventy-five dialysis patients (40% women, 65 ± 15 years), 252 kidney transplant patients (33% women, 54 ± 14 years) and 71 controls (65% women, 44 ± 14 years) were followed. Three months or longer after vaccination we detected anti S1/S2 IgG antibodies in 79% of dialysis patients, 42% of transplant recipients and 100% of controls, whereas respective rates after infection were 94%, 69% and 100%. Predictors of non-response were older age, diabetes, history of cancer, lower lymphocyte count and lower vitamin-D levels. Factors associated with lower antibody levels in dialysis patients were modality (hemodialysis vs peritoneal) and high serum ferritin levels. In transplant patients, hypertension and higher calcineurin or mTOR inhibitor drug levels were linked with lower antibody response. Vaccination was associated with fewer subsequent infections (HR 0.23, p < 0.05). Moreover, higher antibody levels (particularly above 59 AU/ml) were associated with fewer events, with a HR 0.41 for each unit increased in log10titer (p < 0.05). CONCLUSIONS: Dialysis patients, and more strikingly kidney transplant recipients, mounted reduced antibody response to COVID-19 mRNA vaccination. Lesser humoral response was associated with more infections. Measures to identify and protect non-responsive patients are required.

Prognosis and Treatment of Liver Transplant Recipients in the COVID-19 Era: A Literature Review.

Liver transplantation during the COVID-19 pandemic is challenging. Both donor and recipient issues can be influenced by the risks attributed to the pandemic. Allocation policy may need to be modified and criteria may be influenced by local infection rates and availability of medical facilities. Modifying immunosuppression (IS) protocols is controversial and is not evidence-based. In this study, we review the published literature on liver transplant recipients who were infected with COVID-19. A literature review was performed using PubMed, ScienceDirect, and WHO databases to identify relevant English-language articles published up to May 20, 2020. Fifteen articles reported 120 liver transplant recipients who were infected with COVID-19. Only 10 papers with 22 patients reported full encounter characteristics. Four papers reported 23, 17, 13, and 6 patients, respectively, but with minimal data. One paper reported the authors' own 39 patients' characteristics and demographics. The mean age was 58.2 years with 66% males. The most commonly reported presentations in descending order were fever (91%), cough (36.7%), shortness of breath (SOB) (31.8%), and diarrhea (31.8%). Liver transplant patients infected with COVID-19 were maintained on Tac (79%), mycophenolate (MMF) (48.4%), and Prednisone (29.6%) and were managed by reducing MMF in 14.3% of patients and reducing Tac in 14.3% of patients; 28.6% of patients needed ICU admission, 13.6% of patients had died, and the reported general population COVID-19 mortality rate was 3.4%. The clinical presentation of COVID-19 in liver transplant recipients may be different from the general population, with higher rates of severe disease, complications, and mortality.

Practical recommendations for kidney transplantation in the COVID-19 pandemic.

Kidney transplantation at the time of a global viral pandemic has become challenging in many aspects. Firstly, we must reassess deceased donor safety (for the recipient) especially in communities with a relatively high incidence of coronavirus disease 19 (COVID-19). With respect to elective live donors, if one decides to do them at all, similar considerations must be made that may impose undue hardship on the donor. Recipient selection is also problematic since there is clear evidence of a much higher morbidity and mortality from COVID-19 for patients older than 60 and those with comorbidities such as hypertension, diabetes, obesity and lung disease. Unfortunately, many, if not most of dialysis patients fit that mold. We may and indeed must reassess our allocation policies, but this must be done based on data rather than conjecture. Follow-up routines must be re-engineered to minimize patient travel and exposure. Reliance on technology and telemedicine is paramount. Making this technology available to patients is extremely important. Modifying or changing immunosuppression protocols is controversial and not based on clinical studies. Nevertheless, we should reassess the need for induction therapy across the board for ordinary patients and the more liberal use of mammalian target of rapamycin inhibitors in transplant patients with proven infection.

Kidney Transplantation in the Times of COVID-19 - A Literature Review.

Kidney transplantation at the time of the COVID-19 pandemic is challenging. Modifying the immunosuppression protocols is controversial and not evidence based. In this study, we aim to review the published literature of kidney transplant recipients who encountered COVID-19. A literature review was performed using PubMed, ScienceDirect, and World Health Organization databases to identify relevant English-language articles published up to May 7, 2020. There were 24 articles that reported 129 kidney transplant recipients who encountered COVID-19. The age mean was 54.2 years with 73.7% as males. The most commonly reported presentations in order were fever (82.3%), cough (58%), shortness of breath (33.2%), and fatigue (30.7%). Acute kidney injury was observed in 34.1% of patients. Kidney transplant patients encountered COVID-19 were maintained on tacrolimus (Tac, 92%), mycophenolate mofetil (MMF, 78.8%), and prednisone (Pred, 77%) and were manage by holding MMF in 79.1% of patients and holding Tac in 34.4% of patients. In all, 20% of patients needed Intensive Care Unit (ICU) admission and 24.6% of patients required mechanical ventilation. In all, 18.8% of patients had died compared to the reported general population COVID-19 mortality of 3.4%. The clinical presentation of COVID-19 in kidney transplant recipients may be different from the general population with a higher rate of severe disease, complications including renal failure, and mortality.