NMR-based urinary biomarkers in pediatric primary mitochondrial disorders and chronic kidney disease: shared mitochondrial dysfunction, diverging biosignatures

Urinary metabolomic profiling by NMR revealed a distinct biosignature in pediatric PMD patients without renal involvement, characterized by elevated levels of tryptophan, HVA, and Krebs cycle intermediates, and diminished histidine. The divergent changes in tryptophan, histidine and HVA, suggest a mitochondria-specific metabolic phenotype in PMD. These findings support the use of urinary NMR metabolomics as a non-invasive tool for biomarker discovery in PMD and highlight the potential of integrated, multiparametric metabolic fingerprints for diagnostic refinement and patient stratification.