Mitochondrial Disease and the Kidney With a Special Focus on CoQ Deficiency.

Mitochondrial cytopathies include a heterogeneous group of diseases that are characterized by impaired oxidative phosphorylation, leading to multi-organ involvement and progressive clinical deterioration. Most mitochondrial cytopathies that cause kidney symptoms are characterized by tubular defects, but glomerular, tubulointerstitial, and cystic diseases have also been described. Mitochondrial cytopathies can result from mitochondrial or nuclear DNA mutations. Early recognition of defects in the coenzyme Q (CoQ) biosynthesis is important, as patients with primary CoQ deficiency may be responsive to treatment with oral CoQ supplementation, in contrast to most mitochondrial diseases. A literature search was conducted to investigate kidney involvement in genetic mitochondrial cytopathies and to identify mitochondrial and nuclear DNA mutations involved in mitochondrial kidney disease. Furthermore, we identified all reported cases to date with a CoQ deficiency with glomerular involvement, including 3 patients with variable renal phenotypes in our clinic. To date, 144 patients from 95 families with a primary CoQ deficiency and glomerular involvement have been described based on mutations in , , , , and . This review provides an overview of kidney involvement in genetic mitochondrial cytopathies with a special focus on CoQ deficiency.