Rare Variants in Complement Gene in C3 Glomerulopathy and Immunoglobulin-Mediated Membranoproliferative GN

Copyright © 2023 by the American Society of Nephrology..

BACKGROUND: C3 glomerulopathy and idiopathic immunoglobulin-mediated membranoproliferative GN (Ig-MPGN) are rare complement-mediated kidney diseases. Inherited forms of C3 glomerulopathy/Ig-MPGN are rarely described.

METHODS: Three hundred ninety-eight patients with C3 glomerulopathy ( n =296) or Ig-MPGN ( n =102) from a national registry were screened for three complement genes: factor H ( CFH ), factor I ( CFI ), and C3 . Patients with rare variant (minor allele frequency <0.1%) were included. Epidemiologic, clinical, and immunologic data at diagnosis and kidney outcomes of patients were retrospectively collected.

RESULTS: Fifty-three different rare variants, including 30 (57%), 13 (24%), and ten (19%) in CFH , CFI , and C3 variants, were identified in 66/398 (17%) patients. Thirty-eight (72%) variants were classified as pathogenic, including 20/30 (66%) and 11/13 (84%) variants in CFH and CFI , respectively, impairing synthesis of factor H or factor I regulators. Fifteen of 53 (27%) variants were of unknown significance. At diagnosis, 69% of patients were adult (median age of 31 years). With the exception of biologic stigma of thrombotic microangiopathy, which was more frequent in patients with CFI variants (5/14 [36%] versus 1/37 [3%] and 0% in the CFH group and C3 group, respectively, P < 0.001), the clinical and histologic features were similar among the three variants groups. The kidney outcome was poor regardless of the age at onset and treatment received. Sixty-five percent (43/66) of patients with rare variant reach kidney failure after a median delay of 41 (19-104) months, compared with 28% (55/195) after a median delay of 34 (12-143) months in the nonvariant group. Among 36 patients who received a kidney transplant, 2-year recurrence was frequent, occurring in 39% (12/31), without difference between variant groups, and led to graft failure in three cases.

CONCLUSIONS: In our cohort, 17% of C3 glomerulopathy/Ig-MPGN cases were associated with rare variants in the CFH , CFI , or C3 genes. In most cases, a quantitative deficiency in factor H or factor I was identified. The presence of a rare variant was associated with poor kidney survival.

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Medienart:

E-Artikel

Erscheinungsjahr:

2023

Erschienen:

2023

Enthalten in:

Zur Gesamtaufnahme - volume:18

Enthalten in:

Clinical journal of the American Society of Nephrology : CJASN - 18(2023), 11 vom: 01. Nov., Seite 1435-1445

Sprache:

Englisch

Beteiligte Personen:

Meuleman, Marie Sophie [VerfasserIn]
Vieira-Martins, Paula [VerfasserIn]
El Sissy, Carine [VerfasserIn]
Audard, Vincent [VerfasserIn]
Baudouin, Véronique [VerfasserIn]
Bertrand, Dominique [VerfasserIn]
Bridoux, Frank [VerfasserIn]
Louillet, Férielle [VerfasserIn]
Dossier, Claire [VerfasserIn]
Esnault, Vincent [VerfasserIn]
Jourde-Chiche, Noémie [VerfasserIn]
Karras, Alexandre [VerfasserIn]
Morin, Marie-Pascale [VerfasserIn]
Provot, François [VerfasserIn]
Remy, Philippe [VerfasserIn]
Ribes, David [VerfasserIn]
Rousset-Rouviere, Caroline [VerfasserIn]
Servais, Aude [VerfasserIn]
Thervet, Eric [VerfasserIn]
Tricot, Leila [VerfasserIn]
Zaidan, Mohamad [VerfasserIn]
Wynckel, Alain [VerfasserIn]
Zuber, Julien [VerfasserIn]
Le Quintrec, Moglie [VerfasserIn]
Frémeaux-Bacchi, Véronique [VerfasserIn]
Chauvet, Sophie [VerfasserIn]

Links:

Volltext

Themen:

80295-65-4
9001-32-5
Complement C3
Complement Factor H
Fibrinogen
Immunoglobulins
Journal Article
Research Support, Non-U.S. Gov't

Anmerkungen:

Date Completed 09.11.2023

Date Revised 13.11.2023

published: Print-Electronic

Citation Status MEDLINE

doi:

10.2215/CJN.0000000000000252

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM361143354