PYRIDOXINE DEFICIENCY

 

PYRIDOXINE DEFICIENCY

 

DEFINITION:

A metabolic disorder inheritied as an autosomal recessive trait and characterized by neonatal seizures.

EPIDEMIOLOGY:

  • incidence: ?
  • age of onset:
    • in utero or soon after birth (seizures)
  • risk factors:
    • familial - autosomal recessive
      • chrom. #: ?2q31
      • gene: ?

PATHOGENESIS:

  • as pyridoxine (Vit B6) acts as a cofactor for glutamic acid decarboxylase, a deficiency in pyridoxine results in a relative deficency of GAD and thus interferes with the synthesis of GABA.

CLINICAL FEATURES:

1. Seizures

  • focal or multifocal clonic, myoclonic
  • may occur in utero or neonatally
  • seizures may progess to status
  • may be accompanied by meconium-staining, hypotonia, and other signs of fetal distress
  • mental deficiency if persistent seizures are left untreated

INVESTIGATIONS:

1. EEG

  • characterized by generalized spike, polyspike and burst-suppression patterns

2. Biochemical

  • plasma or CSF pyridoxal-5-phosphate

MANAGEMENT:

1. Antiepileptic Medications

  • seizures highly refractory

2. Pyridoxine

  • acute - seizure and EEG responds in minutes in 100 mg IV of pyridoxine
  • chronic - pyridoxine supplementation is needed for life
    • 2-30 mg/kg/day

 

 

 

Pediatric Database - PYRIDOXINE DEFICIENCY

Pediatric Organization - Pedbase [at] Gmail.com