Periodic Paralysis in a Child With Thermosensitive Mitochondrial Trifunctional Protein Deficiency.

Mitochondrial trifunctional protein (MTP) deficiency is a fatty acid oxidation disorder associated with a spectrum of phenotypes. Patients with high residual enzyme activity tend to have milder phenotypes, and recently, fever-induced episodic myopathy was reported in association with a thermosensitive form of MTP deficiency. We report a 10-year-old male with recurrent episodes of acute flaccid paralysis involving upper and lower extremities in association with bulbar muscle weakness in the context of febrile illness, a phenotype reminiscent of recurrent periodic paralysis.

Thermo-sensitive mitochondrial trifunctional protein deficiency presenting with episodic myopathy.

Mitochondrial trifunctional protein (MTP) is involved in long-chain fatty acid β-oxidation (lcFAO). Deficiency of one or more of the enzyme activities as catalyzed by MTP causes generalized MTP deficiency (MTPD), long-chain hydroxyacyl-CoA dehydrogenase deficiency (LCHADD), or long-chain ketoacyl-CoA thiolase deficiency (LCKATD). When genetic variants result in thermo-sensitive enzymes, increased body temperature (e.

Characterization of L-aminocarnitine, an inhibitor of fatty acid oxidation.

The pathogenesis of hypoketotic hypoglycemia and cardiomyopathy in patients with fatty acid oxidation (FAO) disorders is still poorly understood. In vitro studies are hampered by the lack of natural mutants to asses the effect of FAO inhibition. In addition, only a few inhibitors of FAO are known.

An improved enzyme assay for carnitine palmitoyl transferase I in fibroblasts using tandem mass spectrometry.

Carnitine palmitoyl transferase I (CPTI), which converts acyl-CoA and carnitine into acyl-carnitine and free CoASH, is the rate limiting enzyme of hepatic mitochondrial beta-oxidation. CPTI-deficiency is a severe disorder characterized by Reye-like attacks with hypoketotic hypoglycemia, hepatomegaly, elevated liver enzymes and hyperammonemia. We developed a simple tandem-MS-based assay to measure CPTI activity in human fibroblasts.