Порушення метаболізму гліцину

Nonketotic hyperglycinemia (605899*)

Glycine cleavage enzyme system

Biochemical profile: Elevated plasma and cerebrospinal fluid glycine

Clinical features: In fetuses, severe hiccups

In neonatal form, severe hiccups, hypotonia, seizures, myoclonus, apnea, death

In infantile and episodic forms, seizures, intellectual disability, episodic delirium, chorea, vertical gaze palsy

In late-onset form, progressive spastic diplegia, optic atrophy, but no cognitive impairment or seizures

Treatment: No effective treatment; in some patients, temporary benefit from sodium benzoate and dextromethorphan

In some patients with specific mutations, benefit from cofactor therapy with pyridoxine (GLDC mutations) or folinic acid (AMT mutations)

P protein

H protein

T protein

L protein