Mitochondrial-associated nephropathies in adulthood ; Implication des mitochondriopathies dans les néphropathies de l'adulte

Background: mitochondrial functions integrate the regulation of reactive oxygen species, cell survival, apoptosis, and energy production. These functions are controlled by genes of both mitochondrial and nuclear DNA. Pathogenic variants affecting any of these are responsible for primary mitochondrial disorders (MIDs), that can be diagnosed during adulthood. The kidneys’ functions are highly dependent on mitochondrial respiration. However, the prevalence of MID-associated nephropathies (MIDANs) is unknown in the adult population. Methods: adults (≥16-years-old) with genetically diagnosed MID between 2000 and 2020 in our tertiary care academic center, were included in a retrospective observational study when they had a kidney disease (KD) evaluation. MIDANs were ascertained by KD occurring in MIDs. The phenotypic, biological, histopathological, and genotypic characteristics were recorded from the medical charts. Results: we included 80 MID-affected adults and ascertained MIDANs in 28/80 (35%). KDs were identified before the study for 14/18 (50%) of the adults with MIDAN. MIDANs were mostly tubulointerstitial nephritis (TIN) for 14/28 (50%), and glomerular disease (GD) for 9/28 (32.1%). MIDAN was independently associated with higher albumin level [odds ratio (OR), 0.79; 95% confidence interval (95%CI), 0.67–0.95], hypertension (OR, 4.23; 95%CI, 1.04-17.17), and vision abnormalities (OR, 0.17; 95%CI, 0.03–0.94). In contrast, the histopathological and genotypic characteristics were not associated with MIDANs. Conclusion: MIDANs are frequent and underestimated among adult MIDs. They are mostly represented by TIN or GD. Vision abnormalities, hypertension and albumin levels were independently associated with MIDANs. Our results pave the way for larger prospective studies investigating MIDANs prevalence among undetermined KD populations. ; Contexte : les mitochondries assurent la régulation des espèces réactives de l’oxygène, la survie cellulaire, l’apoptose et la production d’énergie. Ces fonctions sont contrôlées par ...