Introduction: Due to an increased risk of infection after transplantation vaccinations should be administered before the procedure whenever feasible. The association between infection and autoimmunity among genetically predisposed individuals has been demonstrated. Some cases of de Novo occurrence of HLA antibodies following vaccination against influenza, pneumococcus, hepatitis B, and COVID-19have been documented. Many plausible pathways for the production of HLA antibodies (Abs) induced by vaccination have been proposed, such as encouraging T and B cells to respond to vaccination antigens that cross-react with HLA proteins, the release of cytokines that reactivate memory response, and the effect of vaccine adjuvants. We present the case of a girl with ESRD with transient HLA antibodies in temporal relation to vaccination.

Case: 5-year-old, female, diagnosed with autosomal recessive polycystic kidney disease, ESRD, mild liver fibrosis. No genetic study is available. Premature birth due to severe oligoamnios, with creatinine 0.9 mg/dl, metabolic acidosis, and arterial hypertension. She is in conservative treatment for ESRD until age 4 when she enters the continuous outpatient peritoneal dialysis program. No history of blood transfusions. In 2021, she receives the following vaccines, March: anti-influenza (annual dose), May: varicella vaccine (booster), May, June, and September: Hepatitis B vaccine (double dose) without seroconversion, thus the scheme was repeated in October and November. In October 2021, histocompatibility studies were carried out: HLA Typing (SSO-Luminex) A*02,30; B*44,51; DRB1*04,07; HLAAb screening with single Antigen Bead (SAB), Class I: B76 (MFI 1500–3000); Class II: DR4, DR7, DR9 (MFI 3001-5000). Note that anti-DR4 and DR7 antibodies appear to be autoantibodies (although there is no high-resolution typing available to confirm that the Abs are specific to self HLA antigens). The SAB was repeated after one month, using a different brand of reagents, obtaining identical results. After four months, in February 2022, a third serum sample was tested with SAB, this time with a negative result for HLA Abs.

Conclusion: Current clinical guidelines recommend vaccination of solid organ transplant candidates against various pathogens. The development of de novo antibodies against HLA after an external stimulus different from HLA antigens is possible. More studies are needed to better understand this post-vaccination phenomenon and its clinical implications.