Objective:

We describe an infant with SSDAHD complicated by refractory status epilepticus in the setting of COVID.  

Background:

Succinate semi-aldehyde dehydrogenase deficiency (SSADHD) is a gamma-amino butyric acid degradation defect. It is associated with seizures in 50% of patients. Various types of seizures including myoclonic, tonic-clonic, absence seizures and status epilepticus have been reported. Accumulation and persistently elevated levels of GABA can lead to downregulation of GABA receptors, resulting in decreased inhibitory tone and increased seizure susceptibility.

Design/Methods:

Medical chart and literature review.

Results:

An 11-month-old female with SSADHD was admitted with COVID-19 infection. On day 9, she developed facial twitching, right arm jerking, and rightward eye deviation. EEG confirmed focal status epilepticus. Despite treatment with lorazepam, levetiracetam, fosphenytoin, and phenobarbital, seizures persisted, evolving into refractory status epilepticus. Ketamine infusion was started and escalated to 100 mcg/kg/min without resolution. Pentobarbital was then initiated and titrated to 5 mg/kg/hr, achieving burst suppression and seizure cessation approximately 36 hours after onset. Both anesthetic infusions were weaned over 20 days, during which levetiracetam, topiramate, clobazam, perampanel, and phenobarbital were uptitrated. At discharge, seizures were well controlled, and the patient had returned near her neurological baseline. At one-year follow-up, phenobarbital was weaned, and the remaining antiseizure medications were continued with adequate seizure control. 

Conclusions:

Epilepsy is a recognized feature of SSADHD, though its pathophysiology and optimal management remain poorly defined. Seizure type, frequency, and treatment response are highly variable, making therapy challenging. Status epilepticus in this setting presents unique therapeutic challenges, as many conventional antiseizure agents may exacerbate GABAergic imbalance; thus, management must balance seizure control while avoiding agents that impair GABA metabolism. There are no evidence-based, standardized protocols for managing seizures in SSADHD or many other metabolic epilepsies. This case underscores the complexity of treating metabolic epilepsies and the ongoing need for targeted, mechanism-based therapies.