Should We Vaccinate Our Kids (After Renal Transplant)?

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Working at a children's hospital with a busy renal transplant program, our goal is to get children caught up with any vaccinations they are eligible to receive before they receive a donor kidney. Children with CKD should be vaccinated according to the same CDC schedule as children without kidney disease. However, they may require boosters prior to renal transplantation for vaccines that don't induce as optimal an immunogenic response in CKD, particularly pneumococcus and hepatitis B.

What about after renal transplantation? Sometimes children are unable to complete a vaccine series due to age or because a new vaccine is brought to market after they receive their transplant, such as the HPV quadrivalent vaccine.  Live vaccines, such as MMRV and rotavirus, are generally contraindicated in immunocompromised patients due to risk of reactivation and life-threatening disease. But what about the safety and efficacy of inactivated vaccines?

Many recent studies on the efficacy and safety of post-transplant vaccination have focused on the inactivated influenza vaccine, since it is given annually and allows for easier monitoring. A survey of United Network for Organ Sharing (UNOS)-certified kidney transplant centers demonstrated an increase in influenza vaccination rates from 84% of responding centers in 1999 to 95% in 2009. The minority of transplant centers that continue to not routinely vaccinate post-transplant commonly cite a lack of immunogenicity and concerns of safety, particularly with the risk of causing acute rejection by inducing de novo production of anti-HLA antibodies.

Immunogenicity may be lower with certain vaccines, such as the influenzaHPV, or meningococcal vaccines, if given early after renal transplantation (usually within the first 3-6 months, especially if induction therapy is provided). In a Midwest Pediatric Nephrology Consortium study, the rate of seroconversion with the influenza vaccine was not significantly different between renal transplant recipients and controls. There was no difference in seroconversion based on type of immunosuppressive regimen (steroid-free vs. steroid-based), but antibody titers 8 weeks post-vaccination in both renal transplant groups were significantly lower than the control group. Furthermore, antibody titers in response to other vaccinations given after transplantation, such as that seen with pneumococcus, may decline more rapidly than in controls. Though immunogenicity of vaccines given after transplant may be suboptimal, the risk of serious morbidity and mortality is much higher in immunocompromised patients from the diseases these vaccines prevent.

Though there is concern that vaccination post-transplant can lead to acute rejection, there is limited evidence to support this. A Swiss study assessed the risk of de novo anti-HLA antibody production in two cohorts of adult kidney transplant recipients after receiving a triple injection of two doses of the H1N1 vaccine and the seasonal influenza vaccine. 17.3% of subjects in the first cohort (16 of 92) and 11.9% of subjects in the second cohort (7 of 59) had new anti-HLA antibodies detected 6 weeks after completion of the immunization series. In 6 month follow-up of 20 subjects from both cohorts who had developed anti-HLA antibodies, 13 developed donor-specific antibodies (DSA) and two had biopsy-proven episodes of kidney function decline that could have been attributed to anti-HLA antibodies (one had thrombotic microangiopathy, one had antibody-mediated rejection). Another study looking at H1N1 vaccination found only a 24-28% increase in seroprotection after vaccination between two cohorts, and while there were no clinical rejection episodes nearly 12% of the first cohort developed new anti-HLA antibodies. Other studies have shown opposing data, and current clinical practice guidelines on vaccination in solid organ transplant recipients advise that there is no proven link between vaccination and the risk of acute rejection.

How does your transplant center approach vaccination after renal transplantation?