Dietary management of long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency (LCHADD). A case report and survey.

Current dietary management of long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD; long-chain-(S)-3-hydroxyacyl-CoA:NAD+ oxido-reductase, EC 1.1.1.211) deficiency (LCHADD) is based on avoiding fasting, and minimizing energy production from long-chain fatty acids. We report the effects of various dietary manipulations on plasma and urinary laboratory values in a child with LCHADD. In our patient, a diet restricted to 9% of total energy from long-chain fatty acids and administration of 1.5 g medium-chain triglyceride oil per kg body weight normalized plasma acylcarnitine and lactate levels, but dicarboxylic acid excretion remained approximately ten times normal. Plasma docosahexaenoic acid (DHA, 22:6n-3) was consistently low over a 2-year period; DHA deficiency may be related to the development of pigmentary retinopathy seen in this patient population. We also conducted a survey of metabolic physicians who treat children with LCHADD to determine current dietary interventions employed and the effects of these interventions on symptoms of this disease. Survey results indicate that a diet low in long-chain fatty acids, supplemented with medium-chain triclyceride oil, decreased the incidence of hypoketotic hypoglycaemia, and improved hypotonia, hepatomegaly, cardiomyopathy, and lactic acidosis. However, dietary treatment did not appear to effect peripheral neuropathy, pigmentary retinopathy or myoglobinuria.