ESPN 54th Annual Meeting

ESPN 2022


 
Low post vaccine antibody titers in children with idiopathic nephrotic syndrome treated with rituximab
CLAIRE HERBEZ REA 1 JULIE ALSUGUREN 1 CYRIELLE PARMENTIER 1 CLAIRE DOSSIER 2 OLIVIA BOYER 3 JULIEN HOGAN 2 JEAN-DANIEL DELBET 1 TIM ULINSKI 1

1- TROUSSEAU HOSPITAL
2- ROBERT DEBRE HOSPITAL
3- NECKER HOSPITAL
 
Introduction:

 

Infections remain a major complication in children with idiopathic nephrotic syndrome (INS). We report post-vaccination antibody (Ab) levels for hepatitis B, measles, diphtheria, tetanus and varicella in patients with steroid dependent INS treated with Rituximab (RTX).

Material and methods:

 

We carried out a retrospective study in the pediatric nephrology units of Trousseau, Necker and Robert Debre hospitals. All children with a diagnosis of INS treated with RTX were included. Post vaccine Ab titers and the following clinical and biological parameters were analyzed: age at diagnosis of INS, number of relapses before and after RTX, duration of INS, other immunosuppressive treatment, immunoglobulin levels, duration of B cell depletion, time between the last RTX dose and time interval between the last relapse and post-vaccination serologies. The primary endpoint was a positive antibody titer.

Results:

 

37 patients were included. The median age at INS diagnosis was 3.5 (2.5-6.3) years, the median duration of the INS was 9 (5.0-12.5) years, the median time between the last relapse and post-vaccination serology sampling was 17 (6.5-31) months, the median IgG level was 8.3 (6.6-10.4) g/L. 23/37 (62%) patients received calcineurin inhibitors during disease course, 25/37 (67%) received MMF, 15/37 (40%) received both and 24/37 (65%) received Levamisole. The median duration of B cell depletion was 7.5 (3.3-11.5) years and the time between the last RTX dose and vaccine serologies was 14 (6-29) months. The percentage of positive vaccine titers for hepatitis B, measles, diphtheria / tetanus and chickenpox were 35%, 62%, 48% and 32% respectively, all lower than in healthy children. When compared to INS patients on oral drugs without RTX, the percentages of positive titers were the same for hepatitis B and measles, but lower for diphteria/tetanus and varicella (85%-83%).

Conclusions:

 

INS patients treated with RTX had inadequate post-vaccination antibody titers, which did not correlate with any specific treatment modality.