C3 glomerulopathy is highly prevalent in French Polynesia

To compare the natural history of C3 glomerulopathy (C3G) to acute post-infectious glomerulonephritis (APIGN) in a cohort of patients with a relative homogeneity of environment conditions and genetic background. We retrospectively reviewed the characteristics of all patients with biopsy proven C3G or APIGN referred in 2013–2019 to the only renal unit in French Polynesia. Point prevalence of C3G is ∼23 cases per 100,000 inhabitants. A recurrent variation of CFI (p.Arg406His) was identified at the heterozygous state in 4/8 (50 %) patients with C3G but its pathogenicity remain elusive. Characteristics at presentation and kidney outcomes were roughly similar between C3G (n = 16) and APIGN (n = 20), excepted for the presence of humps on kidney biopsy. C3G is highly prevalent in French Polynesia suggesting specific genetic or environmental susceptibility factors. Systematic diagnosis workflow should be proposed to all patients with C3 predominant glomerulonephritis.