title: The Relationship between Mitochondrial Respiratory Chain Activities in Muscle and Metabolites in Plasma and Urine: A Retrospective Study.
abstract: The relationship between 114 cases with decreased enzymatic activities of mitochondrial respiratory chain (MRC) complexes I-V (C I-V) in muscle and metabolites in urine and plasma was retrospectively examined. Less than 35% disclosed abnormal plasma amino acids and acylcarnitines, with elevated alanine and low free carnitine or elevated C4-OH-carnitine as the most common findings, respectively. Abnormal urine organic acids (OA) were detected in 82% of all cases. In CI and CII defects, lactic acid (LA) in combination with other metabolites was the most common finding. 3-Methylglutaconic (3MGA) acid was more frequent in CIV and CV, while Tyrosine metabolites, mainly 4-hydroxyphenyllactate, were common in CI and IV defects. Ketones were present in all groups but more prominent in combined deficiencies. There was a significant strong correlation between elevated urinary LA and plasma lactate but none between urine Tyrosine metabolites and plasma Tyrosine or urinary LA and plasma Alanine. All except one of 14 cases showed elevated FGF21, but correlation with urine OA was weak. Although this study is limited, we conclude that urine organic acid test in combination with plasma FGF21 determination are valuable tools in the diagnosis of mitochondrial diseases.
authors.affiliation: Monique and Jacques Roboh Department of Genetic Research, Hadassah-Hebrew University Medical Center, P.O. Box 12000, 91120 Jerusalem, Israel. korin@hadassah.org.il.|Metabolic Laboratory, Department of Genetics and Metabolic Diseases, Hadassah-Hebrew University Medical Center, P.O. Box 12000, 91120 Jerusalem, Israel. korin@hadassah.org.il.
authors.forename: Corinne
authors.initials: C
authors.lastname: Alban
authors.affiliation: Metabolic Laboratory, Department of Genetics and Metabolic Diseases, Hadassah-Hebrew University Medical Center, P.O. Box 12000, 91120 Jerusalem, Israel. fatalelena@yahoo.com.
authors.forename: Elena
authors.initials: E
authors.lastname: Fatale
authors.affiliation: Metabolic Laboratory, Department of Genetics and Metabolic Diseases, Hadassah-Hebrew University Medical Center, P.O. Box 12000, 91120 Jerusalem, Israel. abedg@hadassah.org.il.
authors.forename: Abed
authors.initials: A
authors.lastname: Joulani
authors.affiliation: Metabolic Laboratory, Department of Genetics and Metabolic Diseases, Hadassah-Hebrew University Medical Center, P.O. Box 12000, 91120 Jerusalem, Israel. ilin@hadassah.org.il.
authors.forename: Polina
authors.initials: P
authors.lastname: Ilin
authors.affiliation: Monique and Jacques Roboh Department of Genetic Research, Hadassah-Hebrew University Medical Center, P.O. Box 12000, 91120 Jerusalem, Israel. annsr@hadassah.org.il.|Metabolic Laboratory, Department of Genetics and Metabolic Diseases, Hadassah-Hebrew University Medical Center, P.O. Box 12000, 91120 Jerusalem, Israel. annsr@hadassah.org.il.
authors.forename: Ann
authors.initials: A
authors.lastname: Saada
keywords: FGF21; mitochondrial disease; mitochondrial respiratory chain; plasma amino acids; plasma carnitines; urine organic acid