Clinical Guidance
To date, more than 400 individuals with GAA-FGF14-related ataxia have been identified [, , , , , , , , , , , , , , , ]. The following description of the phenotypic features associated with this condition is based on these reports . Table 2. GAA-FGF14-Related Ataxia: Frequency of Select Features
Feature | % of Persons w/Feature | Comment |
|---|
Gait | 95%-100% | — |
Upper limb | 44%-71% | — |
Episodic symptoms | 13%-80% | May be triggered by exercise/ physically demanding tasks, alcohol intake, or caffeine |
Cerebellar dysarthria | 12%-74% | — |
Cerebellar oculomotor signs | 80%-96% | Includes saccadic pursuit, dysmetric saccades, rebound nystagmus, gaze-evoked nystagmus, downbeat nystagmus, impaired visual fixation suppression of vestibuloocular reflex Nystagmus |
Horizontal gaze-evoked | 33%-67% | — |
Downbeat | 10%-67% | May be episodic; at disease onset may occur w/other cerebellar oculomotor signs in absence of other neurologic findings |
Diplopia, oscillopsia, visual blurring | 40%-68% | — |
Decreased vibration sense in distal lower extremities | 29%-57% | — |
Dysphagia | 14%-35% | — |
Vertigo or dizziness | 21%-67% | — |
Postural tremor of upper limbs | 10%-27% | — |
Vestibulopathy | 10%-75% | — |
Spasticity | 3%-21% | Generally mild GAA-FGF14-related ataxia is a mid to late adult-onset slowly progressive cerebellar syndrome with predominant gait involvement. Age of onset and clinical presentation can vary within the same family. The median age at onset is 60 years (range: 21 to 87 years) [, , , , , , ]. |
Source: GeneReviews — "GAA-FGF14-Related Ataxia"
