Stroke-like episodes, peri-episodic seizures, and MELAS mutations

• Published in: European journal of paediatric neurology 2016-11, Vol.20 (6), p.824-829
• Main Authors: Finsterer, Josef, Wakil, Salma Majid
• Format: Article
• Language: English
• Subjects: Aged; Anticonvulsants - therapeutic use; Arginine - genetics; Brain; Cerebrum; Diet, Ketogenic - methods; DNA, Mitochondrial - genetics; Electroencephalography; Encephalopathy; Female; Humans; Male; MELAS Syndrome - diet therapy; MELAS Syndrome - drug therapy; MELAS Syndrome - genetics; Middle Aged; Mitochondrial DNA; Mutation; Seizures - diet therapy; Seizures - drug therapy; Seizures - genetics; Stroke; Stroke - diet therapy; Stroke - drug therapy; Stroke - genetics
• ISSN: 1090-3798; 1532-2130
• DOI: 10.1016/j.ejpn.2016.08.002

Stroke-like episodes (SLEs) are a hallmark of various mitochondrial disorders, in particular MELAS syndrome. SLEs manifest with vasogenic oedema (DWI and ADC hyperintensity) or partial cytotoxic oedema (DWI hyperintensity, ADC hypointensity) in the acute and subacute stage, and with gyriform T1-hyperintensity (cortical necrosis) in the chronic stage. SLEs must be clearly distinguished from ischaemic stroke, since management of these two entities is different. SLEs may go along with or without seizures or epileptiform discharges on EEG. However, in MELAS syndrome seizures may also occur in the absence of SLEs. Focal and generalised seizures have been reported but it is currently unknown if the one or the other prevail. SLEs with and without seizures may respond to NO-precursors l-arginine, succinate, or citrulline. As a supportive measure a ketogenic diet should be initiated. Seizures prior to or during a SLE or paroxysmal EEG-activity during a SLE should be initially treated with antiepileptic drugs (AEDs) with low mitochondrion-toxicity. Only in case these AEDs are ineffective, AEDs with higher mitochondrion-toxicity should be added. All patients with SLEs need to have an EEG recorded irrespective if they have manifesting seizures or not. There are no mtDNA or nDNA mutations which predispose for SLEs with seizures. •Stroke-like episodes (SLEs) in syndromic and non-syndromic mitochondrial disorders (MIDs) may be associated with seizures.•SLEs may be triggered by seizures, why patients with a SLE or paroxysmal activity on EEG should receive antiepileptic drugs (AEDs).•Peri-episodic seizures during SLEs should be treated with AEDs with low mitochondrion-toxic potential and a ketogenic diet.•Nitric-oxide precursors such as l-arginine, citrulline, or succinate may have a beneficial effect also on peri-episodic seizures during a SLE.