Long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD) is one of the constituants of mitochondrial trifunctional protein (see Mitochondrial trifunctional protein deficiency). The isolated deficiency of the LCHAD activity is an autosomal recessive inherited condition, marked with hypotonia, hypoketotic hypoglycemia during long fast or infections usually associated with hypertrophic cardiomyopathy before the age of 2. Most patients later develop retinopathy and peripheral neuropathy. Heterozygous mothers may develop a HELLP syndrome (haemolysis, elevated liver enzymes, low platelets) during the last trimester of pregnancy when fetus is affected. Mutation G1528C is very frequent (90% of mutant alleles) in LCHAD-deficient patients. The study of urinary organic acids and plasmatic acylcarnitines allows to suspect the diagnosis but cannot differentiate LCHAD deficiency from trifunctional protein deficiency. Diagnosis can only be affirmed by identifying the G1528C mutation or by measuring the enzymatic activity. Prenatal diagnosis is available and involves measuring the LCHAD activity and identifying the G1528C mutation in chorionic villi (directly or cultured) or in cultured amniocytes.
Last update: March 2004
- Dr Christine VIANEY-SABAN