Infantile hypophosphatasia without bone deformities presenting with severe pyridoxine-resistant seizures

Mol Genet Metab. 2014 Mar;111(3):404-407. doi: 10.1016/j.ymgme.2013.09.014. Epub 2013 Sep 26.

Abstract

An infant carrying a heterozygous c.43_46delACTA and a heterozygous c.668 G>A mutation in the ALPL gene with hypophosphatasia in the absence of bone deformities presented with therapy-resistant seizures. Pyridoxal phosphate was extremely high in CSF and plasma. Pyridoxine treatment had only a transient effect and the severe encephalopathy was fatal. Repeated brain MRIs showed progressive cerebral damage. The precise metabolic cause of the seizures remains unknown and pyridoxine treatment apparently does not cure the epilepsy.

Keywords: Alkaline phosphatase; Encephalopathy; Hypophosphatasia; Pyridoxine therapy; Therapy resistant seizures.

Publication types

  • Case Reports

MeSH terms

  • Alkaline Phosphatase / genetics
  • Drug Resistance
  • Epilepsy / complications
  • Epilepsy / mortality
  • Epilepsy / pathology*
  • Humans
  • Hypophosphatasia / blood
  • Hypophosphatasia / cerebrospinal fluid
  • Hypophosphatasia / genetics*
  • Hypophosphatasia / mortality
  • Hypophosphatasia / pathology*
  • Infant
  • Male
  • Pyridoxal Phosphate / blood
  • Pyridoxal Phosphate / cerebrospinal fluid
  • Pyridoxine / administration & dosage*
  • Seizures / genetics
  • Seizures / pathology

Substances

  • Pyridoxal Phosphate
  • Alkaline Phosphatase
  • Pyridoxine

Supplementary concepts

  • Hypophosphatasia, Infantile