Immunization after kidney transplantation-what is necessary and what is safe? Nat Rev Nephrol. 2014;10:555-562. [PMID: 25072119 DOI: 10.1038/nrneph.2014.122]

Immunologic Response to SARS-CoV-2 Vaccination in Pediatric Kidney Transplant Recipients: A Systematic Review and Meta-Analysis

The pediatric population is at a lower risk of severe SARS-CoV-2 infection compared to adults. Nevertheless, immunosuppression in pediatric and adolescent kidney transplant recipients (KTRs) increases their hazard compared to the general population. This systematic review evaluates the efficacy of SARS-CoV-2 vaccines and determines the risk factors of no seroconversion in this population. PubMed-MEDLINE databases were searched for cohort studies. A meta-analysis was performed using fixed and random effect models. In total, seven studies including 254 patients were further analyzed. The random effect model demonstrated a 63% seroconversion rate (95% CI 0.5, 0.76) following a two-dose schedule, which increased to 85% (95% CI 0.76, 0.93) after the third dose administration. Seropositivity was lower in patients under mycophenolate mofetil compared to azathioprine (OR 0.09, 95% CI 0.02, 0.43). Rituximab administration decreased the seroconversion rate (OR 0.12, 95% CI 0.03, 0.43). The glomerular filtration rate (GFR) was 9.25 mL/min/1.73 m² lower (95% CI 16.37, 2.13) in patients with no seroconversion. The seroconversion rate was lower in vaccinated compared to infected patients (OR 0.13, 95% CI 0.02, 0.72). In conclusion, vaccination against SARS-CoV-2 in pediatric and adolescent KTRs elicits a humoral response, and a third dose is advised. Previous rituximab administration, antimetabolite therapy with mycophenolate mofetil and lower GFR reduce the likelihood for seroconversion.

Vaccination in patients with kidney failure: lessons from COVID-19

Infection is the second leading cause of death in patients with chronic kidney disease (CKD). Adequate humoral (antibody) and cellular (T cell-driven) immunity are required to minimize pathogen entry and promote pathogen clearance to enable infection control. Vaccination can generate cellular and humoral immunity against specific pathogens and is used to prevent many life-threatening infectious diseases. However, vaccination efficacy is diminished in patients with CKD. Premature ageing of the immune system and chronic systemic low-grade inflammation are the main causes of immune alteration in these patients. In the case of SARS-CoV-2 infection, COVID-19 can have considerable detrimental effects in patients with CKD, especially in those with kidney failure. COVID-19 prevention through successful vaccination is therefore paramount in this vulnerable population. Although patients receiving dialysis have seroconversion rates comparable to those of patients with normal kidney function, most kidney transplant recipients could not generate humoral immunity after two doses of the COVID-19 vaccine. Importantly, some patients who were not able to produce antibodies still had a detectable vaccine-specific T cell response, which might be sufficient to prevent severe COVID-19. Correlates of protection against SARS-CoV-2 have not been established for patients with kidney failure, but they are urgently needed to enable personalized vaccination regimens.

COVID-19 Infection and Response to Vaccination in Chronic Kidney Disease and Renal Transplantation: A Brief Presentation

Chronic kidney disease (CKD) is associated with phenotypic and functional changes in the immune system, followed by detrimental clinical consequences, such as severe infections and defective response to vaccination. Two years of the pandemic, due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), have undoubtedly changed the world; however, all efforts to confront infection and provide new generation vaccines tremendously improved our understanding of the mechanisms of the immune response against infections and after vaccination. Humoral and cellular responses to vaccines, including mRNA vaccines, are apparently affected in CKD patients, as elimination of recent thymic emigrant and naïve lymphocytes and regulatory T-cells, together with contraction of T-cell repertoire and homeostatic proliferation rate, which characterized CKD patients are responsible for impaired immune activation. Successful renal transplantation will restore some of these changes, although several epigenetic changes are irreversible and even accelerated by the induction of immunosuppression. Response to vaccination is definitely impaired among both CKD and RT patients. In the present review, we analyzed the differences in immune response after vaccination between these patients and healthy individuals and depicted specific parameters, such as alterations in the immune system, predisposing to this deficient response.

Pre-transplant donor HBV DNA+ and male recipient are independent risk factors for treatment failure in HBsAg+ donors to HBsAg- kidney transplant recipients

Background

In order to reduce the burden on organ shortage around the world, using potential infectious donor might be an option. However, scarce evidences have been published on kidney transplantation (KTx) from hepatitis B surface antigen (HBsAg) + donors to HBsAg- recipients [D (HBsAg+)/R(HBsAg-)] without hepatitis B virus (HBV) immunity. Here, we reported the results of D(HBsAg+/HBV DNA- or +)/R(HBsAg-) living KTx recipients with or without HBV immunity.

Methods

We retrospectively identified 83 D(HBsAg+)/R(HBsAg-) living KTx recipients, and 83 hepatitis B core antibody (HBcAb) + living donors to HBcAb- recipients [D(HBcAb+)/R(HBcAb-)] were used as control group by reviewing medical archives and propensity score matching. Treatment failure (defined as any HBV serology conversion, liver injury, graft loss, or recipient death) is the primary endpoint.

Results

Twenty-four donors (28.9%) were HBV DNA+, and 20 recipients had no HBV immunity in the D(HBsAg+)/R(HBsAg-) group pre-transplantation. HBV prophylaxis was applied in all D(HBsAg+)/R(HBsAg-) recipients, while none was applied in the D(HBcAb+)/R(HBcAb-) group. We observed a significant higher treatment failure in D(HBsAg+)/R(HBsAg-) than D(HBcAb+)/R(HBcAb-) group (21.7% vs. 10.8%, P < 0.001). Interestingly, no significant difference was found between groups on HBV seroconversion, liver and graft function, rejection, infection, graft loss, or death. However, 2/20 recipients without HBV immunity in the D(HBsAg+)/R(HBsAg-) group developed HBV DNA+ or HBsAg+, while none observed in the D(HBcAb+)/R(HBcAb-) group. HBV DNA+ donor and male recipient were significant risk factors for treatment failure.

Conclusion

D(HBsAg+)/R(HBsAg-) should be considered for living kidney transplantation, but with extra caution on donors with HBV DNA+ and male candidates.

Kidney Transplantation From Hepatitis B Surface Antigen (HBsAg)–Positive Living Donors to HBsAg-Negative Recipients: Clinical Outcomes at a High-Volume Center in China

Background

Data on kidney transplantation (KTx) from hepatitis B surface antigen (HBsAg)–positive (HBsAg+) donors to HBsAg-negative (HBsAg−) recipients [D(HBsAg+)/R(HBsAg-)] are limited. We aimed to report the outcomes of D(HBsAg+)/R(HBsAg−) KTx in recipients with or without hepatitis B surface antibody (HBsAb).

Methods

Eighty-three D(HBsAg+)/R(HBsAg−) living KTx cases were retrospectively identified. The 384 cases of KTx from hepatitis B core antibody–positive (HBcAb+) living donors to HBcAb-negative (HBcAb−) recipients [D(HBcAb+)/R(HBcAb−)] were used as the control group. The primary endpoint was posttransplant HBsAg status change from negative to postive (-− →+).

Results

Before KTx, 24 donors (28.9%) in the D(HBsAg+)/R(HBsAg−) group were hepatitis B virus (HBV) DNA positive, and 20 recipients were HBsAb−. All 83 D(HBsAg+)/R(HBsAg−) recipients received HBV prophylaxis, while no D(HBcAb+)/R(HBcAb−) recipients received prophylaxis. After a median follow-up of 36 months (range, 6–106) and 36 months (range, 4–107) for the D(HBsAg+)/R(HBsAg−) and D(HBcAb+)/R(HBcAb−) groups, respectively, 2 of 83 (2.41%) D(HBsAg+)/R(HBsAg−) recipients and 1 of 384 (0.26%) D(HBcAb+)/R(HBcAb−) became HBsAg+, accompanied by HBV DNA-positive (P = .083). The 3 recipients with HBsAg−→+ were exclusively HBsAb−/HBcAb− before KTx. Recipient deaths were more frequent in the D(HBsAg+)/R(HBsAg−) group (6.02% vs 1.04%, P = .011), while liver and graft function, rejection, infection, and graft loss were not significantly different. In univariate analyses, pretransplant HBsAb−/HBcAb− combination in the D(HBsAg+)/R(HBsAg−) recipients carried a significantly higher risk of HBsAg−→+, HBV DNA−→+, and death.

Conclusions

Living D(HBsAg+)/R(HBsAg−) KTx in HBsAb+ recipients provides excellent graft and patient survivals without HBV transmission. HBV transmission risks should be more balanced with respect to benefits of D(HBsAg+)/R(HBsAg−) KTx in HBsAb-/HBcAb− candidates.

Impact of Pharmacy-Initiated Interventions on Influenza Vaccination Rates in Pediatric Solid Organ Transplant Recipients

BACKGROUND

In solid organ transplant (SOT) recipients, influenza infection can lead to subsequent graft dysfunction and death. Vaccination is the most effective approach to preventing influenza infection; however, vaccination rates are low, and interventions to optimize vaccine coverage are needed. The purpose of this study was to evaluate if pharmacy-initiated screening and recommendations for influenza immunization improve the rate of vaccination in pediatric SOT recipients.

METHODS

We performed a retrospective pre-post chart review of all kidney, liver, and heart transplant recipients followed by Children's Healthcare of Atlanta/Emory University transplant services between September 1, 2011, and February 16, 2017. Influenza vaccination coverage and influenza rates before (2011-2013) and after (2014-2016) the implementation of pharmacy-driven vaccination in SOT recipients were assessed.

RESULTS

A total of 822 patients were included; 101 (13%) of these patients were diagnosed with influenza, and 40 (5%) were hospitalized secondarily during the study period. Vaccination coverage increased over time (144 [36%] patients vaccinated in 2011 vs 430 [74%] in 2016; P < .001). Influenza diagnosis rates decreased between the 2 eras (P = .006). The median time in which 50% of the population was vaccinated decreased over time from 163 days in 2012 to 94 days in 2016 (P < .001).

CONCLUSION

Within the constraints of the pre-post study design, we observed a significant increase in influenza vaccination rates after implementation of a transplant pharmacy-initiated screening and vaccination program. The number of patients diagnosed with influenza and the time to vaccination decreased after our pharmacy intervention. All efforts should be made to increase compliance with influenza vaccination; pharmacy-initiated interventions can improve protection against influenza infection in pediatric SOT recipients.

Vaccinations in kidney transplant recipients: Clearing the muddy waters

Vaccine preventable diseases account for a significant proportion of morbidity and mortality in transplant recipients and cause adverse outcomes to the patient and allograft. Patients should be screened for vaccination history at the time of pre-transplant evaluation and vaccinated at least four weeks prior to transplantation. For non-immune patients, dead-vaccines can be administered starting at six months post-transplant. Live attenuated vaccines are contraindicated after transplant due to concern for infectious complications from the vaccine and every effort should be made to vaccinate prior to transplant. Since transplant recipients are on life-long immunosuppression, these patients may have lower rates of serological conversion, lower mean antibody titers and waning of protective immunity over shorter period as compared to general population. Recommendations regarding booster dose in kidney transplant recipients with sub-optimal serological response are lacking. Travel plans should be part of routine post-transplant assessment and pre-travel vaccines and counseling should be provided. More studies are needed on vaccination schedules, serological response, need for booster doses and safety of live attenuated vaccines in this special population.

Current perspectives in assessing humoral immunity after measles vaccination

INTRODUCTION

Repeated measles outbreaks in countries with relatively high vaccine coverage are mainly due to failure to vaccinate and importation; however, cases in immunized individuals exist raising questions about suboptimal measles vaccine-induced humoral immunity and/or waning immunity in a low measles-exposure environment.

AREAS COVERED

The plaque reduction neutralization measurement of functional measles-specific antibodies correlates with protection is the gold standard in measles serology, but it does not assess cellular-immune or other parameters that may be associated with durable and/or protective immunity after vaccination. Additional correlates of protection and long-term immunity and new determinants/signatures of vaccine responsiveness such as specific CD46 and IFI44L genetic variants associated with neutralizing antibody titers after measles vaccination are under investigation. Current and future systems biology studies, coupled with new technology/assays and analytical approaches, will lead to an increasingly sophisticated understanding of measles vaccine-induced humoral immunity and will identify 'signatures' of protective and durable immune responses.

EXPERT OPINION

This will translate into the development of highly predictive assays of measles vaccine efficacy, effectiveness, and durability for prospective identification of potential low/non-responders and susceptible individuals who require additional vaccine doses. Such new advances may drive insights into the development of new/improved vaccine formulations and delivery systems.

Vaccination practices in End Stage Renal Failure and Renal Transplantation; Review of current guidelines and recommendations

Due to the increased burden of infectious complications following solid organ transplantation, vaccination against common pathogens is a hugely important area of discussion and application in clinical practice. Reduction in infectious complications will help to reduce morbidity and mortality post-transplantation. Immunisation history is invaluable in the work-up of potential recipients. Knowledge of the available vaccines and their use in transplant recipients, donors and healthcare providers is vital in the delivery of quality care to transplant recipients. This article will serve as an aide-memoire to transplant physicians and health care professionals involved in managing transplant recipients as it provides an overview of different types of vaccines, timing of vaccination, vaccines contraindicated post solid organ transplantation and travel vaccines.

Vaccination strategies in patients with solid organ transplant: evidences and future perspectives

Solid organ transplant recipients need emphases on immunization that result in certainly decrease the risk of vaccine preventable diseases. Organ transplant candidate should complete the recommended full vaccination schedule as early as possible during the courses of underlying disease because the patients with end stage liver or renal disease have reduced immune response to vaccine. Furthermore, live attenuated vaccines are generally contraindicated after transplantation. This review summarizes current information and the evidences regarding the efficacy and safety of immunization in adult solid organ transplant candidates and recipients.

Vaccine-preventable infection morbidity of patients with chronic kidney disease and cocoon vaccination strategies

Individuals with chronic kidney disease (CKD) are vulnerable to vaccine-preventable infections due to impaired immunity, immunosuppressive treatments and dialysis. Protection of CKD patients by vaccination is hampered by reduced efficacy of vaccines and safety concerns for transplant candidates or recipients. 'Cocooning' vaccination policies, targeting the protection of a vulnerable individual through immunization of close contacts, have recently been introduced for infants and, to a lesser degree, for high-risk groups of immunocompromised individuals. In this article, we discuss the potentiality of implementing cocoon strategies for the high-risk group of CKD patients and conclude that this not yet officially recommended policy can substantially contribute to protection against infection and motivate vaccination among families and healthcare workers.

Live virus vaccines in transplantation: friend or foe?

Solid organ and hematopoietic stem cell transplant recipients may be exposed to diseases which may be prevented through live attenuated virus vaccines (LAVV). Because of their immunosuppression, these diseases can lead to severe complications in transplant recipients. Despite increasing evidence regarding the safety and effectiveness of certain LAVV, these vaccines are still contraindicated for immunocompromised patients, such as transplant recipients. We review the available studies on LAVV, such as varicella zoster, measles-mumps-rubella, influenza, yellow fever, polio, and Japanese encephalitis vaccines in transplant patients. We discuss the current recommendations and the potential risks, as well as the expected benefits of LAVV immunization in this population.