Hypotonia With Lactic Acidemia And Hyperammonemia

This syndrome is characterised by severe hypotonia, lactic academia and congenital hyperammonaemia.

Epidemiology

It has been described in three newborns born to consanguineous parents.

Clinical description

Ultrasound examination during the 36th week of pregnancy revealed generalised oedema. Hypertrophic cardiomyopathy and tubulopathy developed within the first week of life and the infants died within the first month. The activities of enzymes in the mitochondrial respiratory chain were reduced in the muscles of the patients.

Etiology

Mutations were identified in the MRPS22 gene, encoding a mitochondrial ribosomal protein.