Table 1.

Clinical Synopsis of Children With the Homozygous Boricua FRRS1L Variant.

Case no.	Age (y)	Sex (F/M)	Regression (Y/N)	Movement disorder	Seizure onset (mo)	Dysphagia	Respiratory	Seizure semiology	EEG	Brain MRI/CT	CMA results	Current AEDs	Past AEDs
1	14	F	Y	Choreiform	25	Gastrostomy tube	Aspiration pneumonia	Epileptic spasms and tonic seizure	Hypsarrhythmia, then slow spike and wave	Normal at onset, later atrophy	N/A	CBL, LTG LVT, CBDa	ACTH, ZNS, VGB, VPA, RUF, TPM, KD
2	3	F	Y	Choreiform	19	Gastrostomy tube	CPAP	Focal and generalized clonic	Hypsarrhythmia	Trace lactate MRS	N/A	TPM, VGB, CBDa	Pred, GBT, PHB
3	2	M	Y	Choreiform, dystonia		Gastrostomy tube	Recurrent aspiration	Focal, epileptic spasms	Hypsarrhythmia	Cerebellar atrophy, thin CC	N/A	LVT, TPM CBL	N/A
4	2	M	Y	Choreiform	3	Pending evaluation	Room air	Epileptic spams, focal clonic	Hypsarrhythmia	Chronic bleed at R caudothalamic groove	N/A	LVT	VGB, ACTH, CNZ
5	3	M	Y	None	22	Gastrostomy tube	Room air	Focal and generalized clonic	Slow, disorganized background, continuous epileptiform discharges	Normal MRI brain at 10 months, Normal F/U MRI brain at 21 months	Normal	RUF, LVT, KD, CBDa	N/A
6	4	M	Y	Choreiform	18	Fed orally, modified texture	Room air	Generalized tonicclonic	Hypsarrhythmia	Normal MRI at 2yo, no F/U imaging	Normal	VPA	ACTH, VGB
7	4	F	Y	Choreiform	24	Gastrostomy tube	Chronic respiratory failure	Generalized tonicclonic, myoclonic	Hypsarrhythmia	Enlarged subarachnoid spaces at age 1 y, no F/U MRI	Duplication 7q36.2	VPA, CBL, TPM	LAC
8	16	M	Y	Choreiform	8	Gastrostomy tube	Tracheostomy	Generalized tonicclonic	Hypsarrhythmia, then slow spike and wave	Normal at 3 mo, cerebellar atrophy at age 5 y	Normal	CBDa, CBL, LVT, PHT	LTG, PHT, LVT, CNZ, KD
9	28	M	Y	Choreiform	<12	Gastrostomy tube	Tracheostomy	Generalized tonicclonic	Slow spike and wave	Cortical and cerebellar atrophy at age 8 y, worsen by age 12 y	Normal	CBDa	LTG, KD
10	2	F	Y	Choreiform	13	Gastrostomy tube	Nocturnal CPAP	Myoclonic	Hypsarrhythmia	Normal CT brain at 2yo, no F/U imaging	Not tested	CBDa, VPA, LVT, CBL	TPM
11	Deceased at 8	F	Y	Choreiform	12	Gastrostomy tube	Tracheostomy	Myoclonic	Hypsarrhythmia	Normal at age 1-4 y, no F/U imaging	N/A	N/A	LVT, TPM, CBL
12	4	F	Y	Choreiform, myoclonus	26	Fed orally, modified texture	Normal PSG	Secondary generalized tonicclonic, generalized tonic	2-3-Hz rhythmic delta with superimposed multifocal spike discharges	Normal, (MRS GABA/glu peak at 2.3 ppm and trace lactate)	N/A	LVT	None
13	13	M	Y	Choreiform	24	Gastrostomy tube	Difficulty clearing secretions, aspiration	Epileptic spasms	Hypsarrhythmia, then slow spike and wave	Normal MRI brain at 21 mo, no F/U imaging	Normal	TPM, LVT	N/A
14	25	F	N	None	18	Gastrostomy tube	Difficulty clearing secretions	Myoclonic	N/A	Brain atrophy	N/A	LVT, KD	LTG, VNS
15	1	M	N	None	24	Gastrostomy tube	N/A	Generalized tonicclonic myoclonus	Multifocal sharp waves	Normal MRI brain at 7 months, no F/U imaging	Not tested	TPM	N/A

Abbreviations: ACTH, adrenocorticotrophic hormone; AED, antiepileptic drug; CBD, cannabidiol; CBL, clobazam; CC, corpus callosum; CMA, chromosomal microarray; CNZ, clonazepam; CPAP, continuous positive airway pressure; CT, computed tomography; EEG, electroencephalogram; F/U, follow-up; GABA, γ-aminobutyric acid; GBT, gabapentin; glu, glutamate; KD, ketogenic diet; LAC, lacosamide; LTG, lamotrigine; LVT, levetiracetam; MRI, magnetic resonance imaging; MRS, magnetic resonance spectroscopy; N, no; N/A, not available; PHB, phenobarbital; PHT, phenytoin; Pred, prednisone; ppm, parts per million; PSG, polysomnography; R, right; RUF, rufinamide; TPM, topiramate; VGB, vigabatrin; VNS, vagal nerve stimulator; VPA, valproate; Y, yes; ZNS, zonisamide.

^aFood and Drug Administration (FDA)–approved cannabidiol.