RESUMO
Background: SARS-CoV-2 vaccine responses that could harbor potential risks to chronic liver diseased patients. Aims: To assess immune response following Pfizer's SARS-CoV-2 vaccine in patients with different liver fibrosis severities of nonalcoholic fatty liver disease (NAFLD). Methods: Clinical and histological (NAS-score and fibrosis stage) characteristics of NAFLD patients before vaccine were correlated with serologic vaccine responses of two doses of the BNT162b2. Serum SARS-CoV-2 spike immunoglobulins (anti-S) were assessed on day seven following immunization (Liaison assay). Results: The mean-age of patients (n = 157) was 56.9 ± 13.2 years (46.5 % males). 94.8 % had a positive response (anti-S levels ≥ 19 AU/ml). The anti-S cutoff of 200 AU/ml used to separate strong vs. weak responses. A strong response (anti-S titers ≥ 200 AU/ml) was observed in 93/157 (59.2 %) patients with a mean-age of 53.1 ± 13.8 years (45.2 % males). A weak response (anti-S titers < 200 AU/ml) was observed in 64/157 (40.8 %) cases with a mean-age of 62.3 ± 10.2 years (p < 0.0001). The strong response subgroup had lower metabolic comorbidities, including glucose hemostasis, hypertension, and dyslipidemia (p < 0.04). Moreover, the strong response subgroup had fibrosis stages F0-F2 (75.3 % vs. 56.3 %) and lower rates of advanced stages F3-F4 (24.7 % vs. 43.8 %). The F0-F2 subgroups had significantly higher rates of strong responses than the F3-F4 stages. The anti-S ≥ 200 and anti-S ≥ 400 AU/ml response achieved in 66 % and 36.8 % of the F0-F2 population was significantly higher than the 45.1 % (p = 0.006) and 23.5 % (p = 0.05) in the F3-F4 population, respectively. The Fib-4 calculations and Fibroscan evaluations were consistent with histologic fibrosis assessment. Conclusion: Advanced liver fibrosis (assessed by histology, Fib-4, or Fibroscan) is a risk factor for lower response to Pfizer's BNT162b2 vaccine, and patients should be prioritized for the vaccine booster against SARS-CoV-2.
RESUMO
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.
