Letter regarding “Minimal change disease relapse following SARS-CoV-2 mRNA vaccine”

To the editor:

We read with interest the report by Kervella et al. ¹ on a patient with minimal change disease who experienced a relapse of her nephrotic syndrome following severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mRNA vaccine.

We would like to report a similar observation. A 22-year-old adult male patient has been followed up in our department since 2019 for an idiopathic nephrotic syndrome due to minimal change disease. His disease proved to be corticosteroid dependent, and he had 3 relapses of his nephrotic syndrome, requiring prolonged corticosteroid treatment and tacrolimus administration. He experienced his third relapse in December 2020 (Figure 1 ) while receiving no corticosteroids, and during a phase of progressive tacrolimus withdrawal. Complete remission was achieved with increased corticosteroid dosage and tacrolimus reintroduction. Treatment with rituximab was decided but was delayed to allow anti–coronavirus disease 2019 (COVID-19) vaccination. The patient was advised to monitor proteinuria, using urinary dipsticks, more closely after vaccination.

Figure 1.

Evolution over time of the idiopathic nephrotic syndrome in a 22-year-old male patient who experienced a relapse of his nephrotic syndrome following anti–coronavirus disease 2019 (COVID-19) mRNA vaccine. SARS-CoV-2, severe acute respiratory syndrome coronavirus 2; U Alb/Cr, urinary albumin/creatinine.

Three days after receiving SARS-CoV-2 mRNA vaccine (BNT162b2; Pfizer), he presented with a severe nephrotic syndrome relapse (serum albumin, 23 g/L) and persistently normal kidney function (creatinine, 71 μmol/L) (Figure 1). He reported having experienced chills and low-grade fever in the 48 hours following vaccination and positive proteinuria (2+/3+) on dipsticks as early as 36 hours after the injection. Prednisone dosage was increased to 20 mg/d and subsequently to 60 mg/d, tacrolimus was maintained at 1 mg twice daily, but remission was not obtained until 17 days after treatment regimen modification. Subsequently, corticosteroid dosage was progressively decreased to 30 mg/d, and tacrolimus dosage was unchanged. The patient received his second vaccine dose 6 weeks after the first one, while still on immunosuppressive treatment. His urinary dipsticks became transiently faintly positive (+), but no nephrotic syndrome relapse occurred. The patient responded well to vaccination, with a positive SARS-CoV-2 serology (IgG, 95.5 U/ml) documented 7 weeks after the first vaccine injection.

Vaccination (notably, hepatitis B, influenza, measles, and rubella) is a recognized trigger for the relapse of idiopathic nephrotic syndrome,² and SARS-CoV-2 mRNA vaccine is probably to be added to the list of at-risk vaccines. Close monitoring using urinary dipsticks is mandatory after a SARS-CoV-2 mRNA vaccination in patients with idiopathic nephrotic syndrome for an early detection of relapse that may occur despite immunosuppression. Nevertheless, as with other vaccinations, the benefit of immune protection, most probably, outweighs the risk of relapse.