LCHAD

LCHAD : long-chain 3- hydroxyacyl-coenzyme A dehydrogenase ) deficiency is a rare condition that prevents the body from converting certain fats to energy, particularly during periods without food ( fasting ). Normally through a process called fatty acid oxidation, several enzymes work in a step-wise fashion to brakdown ( metabolize ) fats and convert them to energy. People with LCHAD have inadequate levels of an enzyme required for a step that metabolizes a group of fats called long-chain fatty acids.
Catalyzes the third step of mitochondrial oxidation of long chain fatty acids, converting long chain 3-hydroxyacyl0-CoA enters into the corresponding 3-ketoacyl-CoA esters. The LCHAD enzyme is part of the mitochondrial trifunctional protein ( MTP), which also narbors long-chain enoy-CoA hydratase and the long chain thiolase activity.
Diagnosis of LCHAD deficiency is suggested by demonstrating increased secretion of 3-hydroxydicarboxylic acids in urine by gas chromatography mass spectrometry, or by demonstrating accumulation of 3-hydroxyacyl carnitines as measured by tandem-mass-spectrometry in plasma. Confirmation of the diagnosis is possible by measuring LCHAD activity in lymphocytes, fibroblasts, muscle or liver biopsies, and by mutational analysis.

MEDICAL CARE

• If the patient present with acute hypoketotic hypoglycemia encephalophaty, the main goal is to secure sufficient energy intake by infusions of iv glucose.
• The management of affected patients is directed at the avoidance of fasting. Most patients also are provided with uncooked cornstarch and medium chain triglycerida ( MCT ) oil supplementation to further decrease exposure to fasting. Consider carnitine supplementation if any hypocarnitinemia is present, however, carnitine should not be used during acute decompensation.

LAB STUDIES

- Blood sugar and urine ketones

The hallmark biochemical feature is acute hypoketotic hypoglycemia. Collect urine ketones in the acute episode.

- Creatinine phosphokinase, ammonia, uric acid, liver enzymes, lactic acid.Durimg acute episodes, elevated levels of creatinine phosphokinase are observed.Hyperammonemia maybe observed in acute episodes. Elevation of liver trans inase also is observed. A high incidence of lactic acidemia accompanies the metabolic decompensation or acute episode.

- Plasma carnitine levels and acylcarnitine profile.Plasma carnitine levels are low