Neuropediatrics 2015; 46 - FV02-11
DOI: 10.1055/s-0035-1550659

Acute Necrotizing Encephalopathy: Two Cases and the Detection of a New RANBP2 Mutation

K. Storch 1
  • 1Uniklinikum Dresden, Dresden, Germany

Introduction: The acute necrotizing encephalopathy, ANE1 (MIM 608033) is an autosomal dominant disorder with rapidly progressing encephalopathy after common viral infections. It is caused by mutations in the RANBP2 gene. The neuroradiological findings show multiple symmetric lesions in the thalami, pons, midbrain, and brain stem.

Case Report: We report about two cases of 1-year-old boys (P1 and P2) with RANBP2 mutation but different clinical outcome. P1 showed a severe encephalopathy with decrease in brain volume, dilatation of the ventricles, necrosis of the thalami, capsula externa, and brain stem seen on MRI. We found the most common p. T585M mutation in RANBP2 gene.

Over the course of time, the boy developed a spastic tetraparesis, epilepsy, and severe developmental delay. After 8 months, the MRI revealed a global decrease in brain volume, calcified necrosis of thalamus, pons, and capsula externa.

P2 presented with acute hemiparesis and progredient encephalopathy. He suffered from a gastrointestinal infection. The MRI revealed symmetric lesions in the pons. The diagnostic work-up included central pontine myelinolysis and Leigh disease. After 3 months, he was afflicted with status epilepticus during a subfebril infection.

The genetic analysis resulted in a novel heterozygous c. 2043G > C mutation in the RANBP2 gene. The patient received prednisolone (2 mg/kg/d) over a course of 6 days. The symptoms improved significantly, with persistence of a mild hemiparesis.

After 4 months, the MRI revealed pontine residues involving bilateral thalami and temporal lobe.

Conclusion: We want to promote recognition of RANBP2 mutation especially in recurrent or familial episodes of encephalopathy after common viral infections and with typical involvement in MRI. There is no causal therapy, so that symptomatic treatment and early recognition of major importance. Some case reports describe a better outcome after steroid therapy.

Keywords: RANBP2.