3-Hydroxyacyl-Coa Dehydrogenase Deficiency

A number sign (#) is used with this entry because of evidence that 3-alpha-hydroxyacyl-CoA dehydrogenase deficiency is caused by compound heterozygous mutation in the HADH gene (601609) on chromosome 4q25.

Clinical Features

Tein et al. (1991) reported a 16-year-old girl with 3-hydroxyacyl-CoA dehydrogenase deficiency resulting in juvenile-onset recurrent myoglobinuria, hypoketotic hypoglycemic encephalopathy, and hypertrophic/dilated cardiomyopathy. Biochemical analysis showed that HADH enzyme activity was markedly decreased in skeletal muscle cells, whereas it was normal in fibroblasts.

Bennett et al. (1999) reported 3 unrelated patients with HADH deficiency resulting in sudden infant death. Clinically, there were variable features of hypotonia, hypoglycemia, hepatic steatosis, and hypoketotic dicarboxylic aciduria. Postmortem biochemical analysis showed residual liver HADH activity of 3.4%, 6.7%, and 11%; skeletal muscle activity was normal in all 3 patients.

Treacy et al. (2000) reported a case of HADH deficiency presenting as unexpected infant death.

O'Brien et al. (2000) reported a patient with HADH deficiency who presented at age 3 years with fulminant hepatic failure. Liver biopsy showed centrilobular necrosis and lipid accumulation. The patient received a living-related liver transplant and recovered.

Molecular Genetics

In a patient with HADH deficiency presenting as fulminant hepatic failure, O'Brien et al. (2000) identified compound heterozygosity for 2 mutations in the HADH gene (601609.0001; 601609.0002).

Nomenclature

Yang et al. (2005) stated that the enzyme encoded by the HADH gene had previously been referred to as 'SCHAD.' Accordingly, some cases of human metabolic disorders previously reported as 'SCHAD deficiency' are in fact cases of 'HADH deficiency.'