L-Carnitine Improves Skeletal Muscle Fat Oxidation in Primary Carnitine Deficiency.

Context: Primary carnitine deficiency (PCD) is an inborn error of fatty acid metabolism. Patients with PCD are risk for sudden heart failure upon fasting or illness if they are not treated with daily l-carnitine.

Objective: To investigate energy metabolism during exercise in patients with PCD with and without l-carnitine treatment.

Is L-Carnitine Supplementation Beneficial in 3-Methylcrotonyl-CoA Carboxylase Deficiency?

Background: 3-Methylcrotonyl-CoA carboxylase deficiency (3-MCCd) is an autosomal recessive disorder in the catabolism of leucine. In the present study, we investigated the current and prior medical condition of patients with 3-MCCd in the Faroe Islands and their carnitine levels in blood, urine and muscle tissue with and without L-carnitine supplementation to evaluate the current treatment strategy of not recommending L-carnitine supplementation to Faroese 3-MCCd patients.

Methods: Blood and urine samples and muscle biopsies were collected from patients at inclusion and at 3 months.

Recurrent myoglobinuria and deranged acylcarnitines due to a mutation in the mtDNA MT-CO2 gene.

Mitochondrial myopathies commonly present with exercise intolerance typified by breathlessness and fatigue on exercise. In contrast, exercise-induced rhabdomyolysis and myoglobinuria occur rarely. We present a 43-year-old man with a lifelong history of exercise intolerance associated with myalgia and recurrent episodes of exercise-induced myoglobinuria.