Combined Alport Syndrome Type 3A and Mitochondrial Disease Presenting with a Thin Base Membrane and Overt Albuminuria.

Autosomal dominant Alport syndrome (ADAS), which leads to kidney dysfunction, is primarily associated with heterozygous mutations in COL4A3/4. Mitochondrial disease can also lead to kidney dysfunction. We report a rare case of a 29-year-old woman with ADAS and mitochondrial nephropathy, identified through a genetic analysis, revealing a novel in-frame deletion in COL4A3 and a mitochondrial m.3243A>G mutation. Kidney biopsy revealed basement membrane thinning and mitochondrial nephropathy. Treatment with taurine, arginine, and finerenone improved her proteinuria. This case highlights the complexity of diagnosing genetic kidney diseases and underscores the importance of next-generation sequencing in guiding personalized medicine for optimal and precise management.