Table 3.
Main clinical features of patients with paroxysmal neurological manifestations (episodic ataxia, paroxysmal dyskinesia) harboring FGF14 mutation previously reported in the literature.
| Patient |
Choquet Patient 1 |
Choquet Patient 2 |
Choquet Patient 3 |
Amado Patient 1 & 2 |
Choi |
Coebergh patient 1 |
Schesny | Shimojima | |
|---|---|---|---|---|---|---|---|---|---|
| Chromosomal abnormality/FGF14 gene mutation |
NM_004115:c.211_212insA/p.(Ile71Asnfs*27) |
Deletion of 424 kb on chromosome 13q33.1 including FGF14 | NM_175929:c.31A>/p.(Thr11Ala) | Deletion of 202 kb on chromosome 13q33.1 including exons 1‐4 of FGF14 |
NM_175929:c.208+1G>A |
Translocation t(13;21)(q32;q22.3) disrupting FGF14 | |||
| Sex/age at last follow‐up (years) | M/31 | M/NK | F/NK | F/NK | M/46 | M/6 | M/twenties | M/6 | |
| Acute episodes | Episodic ataxia | Episodic ataxia | Episodic ataxia | Episodic ataxia | Episodic ataxia | Episodic ataxia | Episodic ataxia | Paroxysmal dyskinesia | |
| Age at onset | 26 years | NK | NK | Childhood | 39 years | Childhood | Twenties | 8 months | |
| Triggering factor | None | Fatigue exercise | NK | Fever | NK | Fever | High emotional stress levels, physical activity, certain body positions (e.g., bending forward), and caffeine intake | Crying | |
| Duration | NK | 20 min | NK | NK | Hours | NK | Min to hours | 5 min | |
| Frequency (or total number) | NK | 4 times per week | Rare | NK | NK | (3 episodes) | 4 times per month | Several per week | |
| Symptoms | Incoor‐dination, unsteady gait, vertical oscillopsy, dysarthria, headache | Dysarthria, unsteady gait, and diplopia | Vertigo dysatrhia | Ataxia | Dizziness, headache | Ataxia | Intense vertigo, dizziness, nausea, dysphagia, diplopia | Attacks of choreic movements | |
| Treatment | Acetazo‐lamide discontinued due to adverse effects | No | No | No | Response to acetazolamide | No | Improvement after acetazolamide | Valproic acid and phenobarbital non effective | |
| Other paroxysmal signs | Attacks of right upper limb dystonia | No | Head‐ache | No | No | No | No | Breath holding spells from 9 months | |
| Permanent symptoms | Yes | Yes | Yes | Yes | Yes | Yes | Yes | No | |
| Tremor | Yes (From age 29) | No | No | Yes | No | No | UL postural tremor | ||
| Nystagmus | Yes (From age 29) | Yes | Yes | Yes | Yes | Yes | Yes | ||
| Ataxia | Yes (From age 29) | No | No | Yes | No | Yes (From age 2) | Slight | ||
| Learning difficulties | NK | NK | NK | Yes | No | Yes | No | Yes (mental al disability) | |
| Psycho‐motor develop‐ment | NK | NK | NK | NK | Normal | Delayed | Delayed | Mental deficiency | |
NK, not known; UL, upper limb.