ABSTRACT
Introduction: Patients with systemic lupus erythematosus (SLE) are at increased risk of the Coronavirus disease 2019 (COVID-19), whereas vaccines against the COVID-19 increase type I interferon and may trigger SLE flares. Lupus nephritis (LN) is common in adolescents with SLE and usually more severe than in adults. The incidence and severity of renal flare among these patients following COVID-19 mRNA vaccination are limited. Method(s): Adolescents, aged 12-18 years, with SLE and ever biopsy-proven lupus nephritis who had renal remission were prospectively studied following the COVID-19 (BNT162b2) mRNA vaccination. Renal remission was defined as having stable renal function and normal urinalysis at recruitment. SLE disease activity index 2000 (SLEDAI-2K) scores during the last 3 months prior to the vaccination were reviewed, and compared to SLEDAI-2K scores at 1, and 3 months after two-dose primary series. Renal flare included new onset significant proteinuria, abnormal urine sediment, and/or significant increased serum creatinine. Result(s): 35 adolescents (female 88.6%), with mean age of 15.4 +/-1.6 years, were included. Median (IQR) duration of SLE was 41.4 (18.9, 70.4) months. LN included class II (2, 5.7%) class III (2, 5.7%), class IV (12, 34.3%) class V (7, 20.0%), and class III/IV + V (10, 28.6%). Median daily dose of prednisolone prior to vaccination was 5 (2.5, 5) mg. SLEDAI-2K scores at pre-vaccination, 1-, and 3-months post vaccination were not significantly different [2 (0.25,4), 2 (0, 4) and 2 (0, 4);p=0.06). Three (8.6%) patients had renal flare within 3 months post vaccination. One had mild microscopic hematuria and mild proteinuria but improved after increased prednisolone to 0.5 mg/kg/day. Two patients had severe renal flare with biopsy proven LN class IV (1 with class V and 1 with thrombotic microangiopathy). Moreover, one patient developed COVID-19 at 2 months post vaccination without renal flare. Conclusion(s): Within 3 months post COVID-19 mRNA vaccine in adolescents with remission of LN, incidence of renal flare was 8.6%. Renal flare could be severe and required increasing immunomodulatory treatment. Larger population and longer follow-up are needed. No conflict of interestCopyright © 2023