Dados do Trabalho

Título

SPASTIC ATAXIA 5 A RARE CAUSE OF DEVELOPMENTAL REGRESSION: A CASE REPORT

Apresentação do caso único

M.S.J.C, 2 years and 1 month old, male with a history of paroxysmal episodes that occurred when the child was one year and
one month old was admitted to the pediatric department for etiological investigation.
Paroxysmal episodes compatible with bilateral tonic epileptic seizures that began at 11 months
of age. The mother reported that, prior to the episodes, the child had achieved adequate
cephalic support and was able to sit without support, but after the onset of the condition, his
motor milestones regressed. In addition to her clinical condition, she was also suffering from
chronic malnutrition, requiring a nasoenteral tube for feeding.
Neurological assessment revealed irritability, convergent strabismus, slowed blinking on threat,
axial and appendicular hypotonia with hypoactive osteotendinous reflexes and an extended
cutaneous-plantar reflex. Neuroimaging tests, electroencephalogram and cerebrospinal fluid
analysis showed no alterations. A genetic investigation with an exome was requested, which showed a mutation
compatible with the diagnosis of Spastic Ataxia type 5, of autosomal recessive inheritance
(SPAX5).

Discussão

Spastic ataxia type 5 (SPAX5) is a very rare genetic disease. According to the literature, it has a
very low prevalence with less than one case for every 1,000,000 individuals.
This is a genetic disorder caused by mutations in the AFG3L2 gene. This gene is responsible
for the coding of mitochondrial proteases which are important in the quality control of proteins in
the mitochondrial inner membrane, participating in the regulation of ribosomal activity and in the
degradation of malformed proteins.

Comentários finais

The clinical picture compatible with the disease is of an early onset cerebellar ataxia associated
with spasticity, dystonic episodes and progressive myoclonic epilepsy.
Some reports in the literature also include clinical findings of oculomotor apraxia, progressive
dysarthria, dysphagia, motor degeneration and distal weakness with muscle atrophy. Our patient
in question has a different picture from those reported, due to onset with tonic seizures and
regression of neuropsychomotor development, which suggests that more studies are needed to
understand the completeness and phenotypic variability of the clinical manifestations associated
with spastic ataxia type 5.

Referências

Dosi C, Galatolo D, Rubegni A, Doccini S, Pasquariello R, Nesti C, Sicca F, Barghigiani M, Battini R, Tessa A, Santorelli FM. Expanding the clinical and genetic heterogeneity of SPAX5. Ann Clin Transl Neurol. 2020 Apr;7(4):595-601.

Palavras Chave

Spastic ataxia; EXOME; regression