ABSTRACT
Introduction: In December 2020, mRNA COVID-19 vaccines (mCV) obtained marketing authorization for immunisation in COVID-19. A case of IgA nephropathy (IgAN) after COVID-19 mRNA vaccine was reported recently to our pharmacovigilance center (PV). The aim is to analyse cases of IgAN following mCV. Material and methods: We requested the cases in French PV Database with the MedDRA term (HLGT) "nephropathy" with mCV and cases summary contains "iga" AND "Nephropa%". We performed a review of the literature, (equation used: "Glomerulonephritis, IGA" [Mesh]) AND "COVID-19 Vaccines" [Mesh]). Cases with non-evocative chronology, pharmaceutical industry declaration and other identified cause were excluded. Results: Twenty cases were included and concerned 55% of women. Median aged was 39 years [13-63 years] including 2 pediatric patients [13 and 17 years]. Mean time to onset was 3.18 days [1-31d]. Concerned mCV was COMIRNATY® for 60% and SPIKEVAX® for the others. IgAN is observed after the 2nd dose for 16 cases (80%), 1st dose for 2 cases (10%), and both for 2 cases (10%). Sudden onset of macroscopic haematuria was the symptom that revealed the kidney disease for these patients and seven patients was also having acute kidney injury (35%). Among all the patient, 67% had an history of IgAN. Almost all cases resolved spontaneously except in six cases which needed corticoids or cyclophosphamide in one case. Discussion/Conclusion: Two third of cases occurred in patient with pre-existing IgAN, vaccine could also unmask a previously undiagnosed disease [1-2], and we noted two cases of positive rechallenge. The mechanism by which mCV may be associated with IgAN flares is unclear, but suggests it is mediated by a delayed-type hypersensitivity reaction. Vaccine risk seems lower than COVID-19 kidney injury and benefit/risk ratio remains favourable for vaccination [2].