Early-onset progressive encephalopathy associated with NAXE gene variants: a case report of a Turkish child

  • Faruk IncecıkEmail author
  • Serdar Ceylaner
Letter to the Editor


Early-onset progressive encephalopathy with brain edema and/or leukoencephalopathy (PEBEL) is an autosomal recessive severe neurometabolic disorder characterized by rapidly progressive neurologic deterioration associated with a febrile illness. PEBEL is a lethal encephalopathy caused by NAXE gene mutations [1, 2].

The nicotinamide adenine dinucleotides (NAD) and nicotinamide adenine dinucleotide phosphate (NADP) have essential roles in many cellular functions. NAD is involved in a series of catabolic reactions and in mitochondrial energy production, whereas NADP is a key component of numerous biosynthetic processes, as well as cellular antioxidant protection systems [3]. The nicotinamide ring within these cofactors is prone to hydration, forming NADHX or NADPHX, which can be present as R or S epimers and which can further degrade irreversibly to cyclic NAD(P)HX. NADHX can be slowly produced from NADH by GAPDH [4]. NAD(P)HX can also form spontaneously from the normal...



This study was not funded.

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Conflict of interest

The authors declare that there is no conflict of interest regarding this article.

Ethical approval

All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards.

Informed consent

Informed consent was obtained from all individual participants included in the study.


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Copyright information

© Belgian Neurological Society 2019

Authors and Affiliations

  1. 1.Department of Pediatric NeurologyCukurova University Faculty of MedicineAdanaTurkey
  2. 2.InterGen Genetic Research CentreAnkaraTurkey

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