ESPN 54th Annual Meeting

ESPN 2022


 
Response to mRNA vaccines for SARS-CoV-2 in young kidney transplant recipients.
LUIGI CIRILLO 1 ELISA BUTI 1 FRANCESCO CITERA 2 VITO TERLIZZI 3 FRANCESCA BECHERUCCI 1 CARMELA ERRICHIELLO 1 GIOVANNI TACCETTI 3 CHIARA AZZARI 2 PAOLA ROMAGNANI 1

1- NEPHROLOGY AND DIALYSIS DEPARTMET, MEYER CHILDRENS HOSPITAL, FLORENCE, IT
2- IMMUNOLOGY DEPARTMENT, MEYER CHILDRENS HOSPITAL, FLORENCE, IT
3- CYSTIC FIBROSIS DEPARTMENT, MEYER CHILDRENS HOSPITAL, FLORENCE, IT
 
Introduction:

Seroconversion after mRNA SARS-CoV-2 vaccination might be unsatisfactory in Kidney Transplant Recipients (KTRs), ranging in literature between 14-58% after the second dose; however most of the data are based on adult populations given the scarce evidence in the young population.

Material and methods:

Patients aged 16-24 years, renal transplant carriers and age-matched control group without immunosuppression, vaccinated with RNA vaccines; we performed quantitative ELISA assay to quantify IgG anti-spike, anti-capsid and neutralizing (RBD) IgG antibodies for SARS-Cov2; samples were drawn on the day of the second dose of vaccine, one month after and one month after the booster dose.

Results:

18 KTRs and 15 controls with a mean age of 19 years were enrolled. 16 KTRs in therapy with steroids, MMF and CNI; 1 with steroids, CNI; 1 with steroids, MPA and CNI. One patient with a previous diagnosis of COVID19 tested positive for anti-capsid.  At the first sampling 7/18 (39%) patients had seroconversion; at the second sampling 13/18 (72%); 11/12 (92%) at the third sample. KTRs neutralizing antibodies were reduced compared to controls after the second dose (p<0.05); antibody levels became equal only after the booster (p<0.05). This in fact produced a statistically significant increase of neutralizing antibodies compared to the second dose in KTRs (p<0.05). The higher quantitative response to the vaccine was observed in those who were in therapy with MPA or did not take antimetabolite, and have lower dose of MMF; a high response was also found in the patient who had had a previous infection. All patients who went adjunctive immunosuppressive treatments other than maintenance in the previous six months did not show seroconversion.

 

Conclusions:

These findings suggest that a third dose of SARS-CoV-2 mRNA vaccine improves the RBD-specific responses of transplant patients treated with immunosuppressive drugs.