Table 7.
Treatment outcomes of patients with early-onset epileptic encephalopathies
| N of patients | Gene mutation | Response to carbamazepine N (%) |
Response to lidocaine N (%) |
Response to phenytoin N (%) |
Response to other AEDS N (%) |
Maintenance | Side effects | Follow-up |
|---|---|---|---|---|---|---|---|---|
| 66 | KCNQ2 | 40 (61%) Carbamazepine |
4 (6%) lidocaine |
7 (10%) phenytoin |
13 (20%) combination of drugs, including Na-channel blockers | 44 (66%) carbamazepine | 1 methemoglobinemia (on lidocaine) | Follow-up: from 3 months to 10 years. Normal development for BFNE; severe developmental delay in KCNQ2 encephalopathy |
| 6 | KCNQ3 |
1 (16%) oxcarbazepine (20 mg/kg) |
/ | / | 2 (33%) levetiracetam (70–85 mg/kg) |
1 (16%) oxcarbazepine 2 (33%) levetiracetam |
None reported | Normal up to 4 years |
| 1 | KCNT1 | / | / | 0 (0%) |
No response to phenobarbital, lamotrigine, or benzodiazepines. 1 (100%) levetiracetam 10–30 mg/kg |
levetiracetam 30 mg/kg/day | None reported | Seizure decrease (still 1 episode/day) at 14 months |
| 1 | SCN2A | / | / | 1 (100%) phenytoin 20 mg/kg | / | carbamazepine 30 mg/kg | None reported | Severe developmental delay at 2 years |
| 1 | SCN1A | / | / | / | 1 (100%) valproate 50 mg/kg | valproate 50 mg/kg | N/A | Severe developmental delay at 3 years |
| 1 | SCN8A | 0 (0%) oxcarbazepine 80 mg/kg | 0 (0%) phenytoin 20 mg/kg | Seizure reduction on a combination of oxcarbazepine, phenytoin, and lamotrigine | phenytoin, oxcarbazepine, phenobarbital, lamotrigine | N/A | Daily seizures at 6 months |