Clinical spectrum of early onset cerebellar ataxia with retained tendon reflexes: an autosomal recessive ataxia not to be missed

Abstract

Autosomal recessive cerebellar ataxias are a heterogeneous group of neurological disorders. In 1981, a neurological entity comprised by early onset progressive cerebellar ataxia, dysarthria, pyramidal weakness of the limbs and retained or increased upper limb reflexes and knee jerks was described. This disorder is known as early onset cerebellar ataxia with retained tendon reflexes. In this article, we aimed to call attention for the diagnosis of early onset cerebellar ataxia with retained tendon reflexes as the second most common cause of autosomal recessive cerebellar ataxias, after Friedreich ataxia, and also to perform a clinical spectrum study of this syndrome. In this data, 12 patients from different families met all clinical features for early onset cerebellar ataxia with retained tendon reflexes. Dysarthria and cerebellar atrophy were the most common features in our sample. It is uncertain, however, whether early onset cerebellar ataxia with retained tendon reflexes is a homogeneous disease or a group of phenotypically similar syndromes represented by different genetic entities. Further molecular studies are required to provide definitive answers to the questions that remain regarding early onset cerebellar ataxia with retained tendon reflexes.

SYNE1 mutations cause autosomal‐recessive ataxia with retained reflexes in Brazilian patients

“…Misdiagnosis of early‐onset recessive ataxias with retained reflexes is not uncommon as different genes are known to underlie comparable conditions (e.g. FXN, SACS, SPG7, DDHD2, STUB1, PNPLA6 , and SYNE1 ) . Description of SYNE1 ataxia outside the French‐Canadian population is limited.…”

Milestones in Friedreich ataxia: more than a century and still learning

“…There are reports of FRDA with onset of symptoms in the sixth or seventh decades of life, and these cases may be misdiagnosed [11][12][13]. In late-onset phenotypes, the ataxia is usually mild, and some cases may present with retained reflexes (Friedreich ataxia with retained reflexes-FARR) [14][15][16].…”

Adult onset sporadic ataxias: a diagnostic challenge

“…Furthermore, storage diseases, such as Niemann-Pick type C disease, Tay-Sachs disease, Krabbe disease, and other forms of recessive ataxias, such as ataxia with ocular apraxia and ataxia-telangiectasia may rarely present with adult onset ataxia 2,36,55 . Finally, sporadic ataxia may be the clinical presentation of new mutations recently described in autosomal recessive ataxias with adult onset of symptoms, such as SYNE1 mutations 56 .…”