Acute hydrocephalus in nonketotic hyperglycinemia

Abstract

We present four patients with typical neonatal onset non-ketotic hyperglycinemia (NKH) who developed hydrocephalus requiring shunting in early infancy. Brain imaging revealed acute hydrocephalus, a megacisterna magna or posterior fossa cyst, pronounced atrophy of the white matter, and an extremely thin corpus callosum in all. The three older patients had profound developmental disabilities. This suggests that the development of hydrocephalus in NKH is an additional poor prognostic sign.

Cranial Ultrasound in Metabolic Disorders Presenting in the Neonatal Period: Characteristic Features and Comparison with MR Imaging

“…Several studies have been performed on brain MR imaging and histologic findings in metabolic disorders presenting during the neonatal period, 3,4,21,24,[30][31][32][33][34][35][36][37][38][39][40][41][42][43][44][45][46][47][48][49] but cUS findings have only been described in individual case reports. [10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26] cUS has the advantage that it is readily available on neonatal units when infants are admitted.…”

Persistent NKH with transient or absent symptoms and a homozygous GLDC mutation

“…Survivors almost invariably have profound neurological sequelae. 1,5,6 A minority present atypically with later onset, less severe neurological manifestations and milder elevations of glycine levels and ratio. Transient NKH has been reported in a few patients with typical severe neonatal onset and characteristic electroencephalogram (EEG) and biochemical abnormalities that resolve by age 2 months, usually with complete clinical resolution.…”

“…3,4 are clinically similar autosomal recessive developmental disorders. Each is associated with congenital muscular dystrophy, ocular abnormalities, and neuronal migration defects that result from mutations in POMGnT1, 5 fukutin, 6 and POMT1, 7 respectively. Recent studies suggest that aberrant ␣-dystroglycan glycosylation underlies the pathogenesis of these disorders.…”

Clinical Reasoning: A 2-day-old baby girl with encephalopathy and burst suppression on EEG

“…5 Less common findings include retrocerebellar cysts with subsequent hydrocephalus. 6 A glycine peak on magnetic resonance spectroscopy is seen in the most severely affected infants and carries a poor prognosis.…”