Table 1.
Patient demographics and clinical scores.
| # | Site | Sex | Mutation site | Age | Dev. delay | Epilepsy (Seizure type) | Current medication | Neurological features | Motor development | Language development | Neuropsychiatric features | GMFCS | MACS | CFCS |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | IT | m | c. 1702 + 1 G > C | 2 years 10 months | y | y (tonic, myoclonic, and monthly clusters) | None | Axial and distal hypotonia; tremor | Some steps with assistance | No | Autistic features; higher pain threshold | IV | IV | IV |
| 2 | IT | m | Deletion exon 4&5 | 5 years 6 months | y | y (focal, tonic, and no clear triggers) | TPM, PB, and CBD oil. CLB when needed | Hypotonia, dystonia; buccal dyspraxia, hyporeflexia | Not able to walk | No | Autistic features; lower pain threshold | V | V | V |
| 3 | IT | m | c. 704 G > A p. Arg235Gln |
8 years 3 months | y | y (seizure-free since 6 months) | None | Mild tremor, ataxia | Able to walk | No | Autistic features, bruxism | II | IV | IV |
| 4 | NL | m | c. 579–3 C > G | 10 years 6 months | y | n | n/a | Hypotonia; tremor after waking up | Stereotypies; very active | II | III | IV | ||
| 5 | NL | m | c. 620 A > G p. Asp207Gly |
6 years 3 months | y | n | n/a | Tremor | Able to walk | Diagnosed ASD; easily distracted | I | I | II | |
| 6 | NL | m | c. 1216 C > T p. Arg406Cys |
3 years 5 months | y | n | n/a | Hypotonia, ataxia, balance problems. Babinski sign, dysmetria | Unable to walk, | No | IV | n/a | IV | |
| 7 | NL | m | c. 847 G > A p. Glu283Lys |
7 years 6 months | y | y (tonic–clonic, focal, and tonic) | LTG | Dyspraxia, very moveable; tremor, ataxia | Able to walk with support, | Able to speak (correct grammar) | Autistic features, highly (sensory) sensitive; restless; loses concentration rapidly; regression after seizure clusters | I | II | III |
| 8 | NL | m | c. 227 T > C p. Leu76Pro |
3 years 4 months | y | n | n/a | Babinski sign, able to grab objects, | Autistic features | IV | n/a | V | ||
| 9 | DK | f | c.1651C > T p. Arg551Cys |
14 years | y | y (spasms, FIAS, tonic, and tonic–clonic) | CBZ, LEV, and VNS | Axial hypotonus, hypertonus | Unable to walk | No | Profound ID | V | V | V |
| 10 | DK | f | c.794 + 5G > A | 8 years | y | y (FIAS, tonic, and tonic–clonic) | RFM, LTG, CLB, and VNS | Ataxia, poor coordination, hypotonia, oral dyspraxia | Able to walk | No | Autistic features | II | IV | III |
| 11 | DK | f | c.1387G > T p.Glu463* | 14 years | y | y | PER, VPA, CLB, and VNS | n/a | Able to walk | n/a | n/a | n/a | ||
| 12 | DK | m | c.1437-6_1559delinsAT | 10 years | y | y (spasms, FIAS, clonic, tonic-myoclonic, tonic–clonic, and SE) | CLB, LAC, and VNS | Spastic tetraparesis, hypotonia, dyskinesia | Unable to walk | No | Severe/profound ID | V | V | V |
| 13 | DK | m | c.795-2A > T | 11 years | y | y (tonic and atonic) | PER, LAC, CLB, and RFM | Ataxia, poor coordination, dystonia, hypertonus | Able to walk | No | Autistic features, moderate–severe ID | II | IV | III |
| 14 | DK | f | c.1061G > A p. Cys354Tyr |
13 years | y | y (currently seizure-free) | None | n/a | n/a | n/a | n/a | n/a | n/a | n/a |
IT: Italy. NL: The Netherlands. DK: Denmark. Dev. delay: Developmental delay. GMFCS: Gross Motor Function Classification System. MACS: Manual Ability Classification System. CFCS: Communication Function Classification System. ASD: Autism spectrum disorder. CBD: Cannabidiol. CLB: clobazam. CBZ: carbamazepine. LAC: lacosamide. LEV: levetiracetam. LTG: lamotrigine. PB: phenobarbital. PER: perampanel. RFM: rufinamide. TPM: topiramate. VNS: Vagus nerve stimulation. VPA: valproic acid. Age in the table reflects the age at the time of the EEG recording.