A case report of late-onset MELAS with paroxysmal sympathetic hyperactivity syndrome / 中华神经科杂志

ABSTRACT

Paroxysmal sympathetic hyperactivity (PSH) is a syndrome characterized by paroxysmal tachycardia, increased blood pressure, tachypnea, hyperthermia, profuse sweating, abnormal posture or dystonia. It occurs in diseases such as moderate to severe brain injury, cerebral hypoxia, hydrocephalus, brain tumor and encephalitis. At present, the etiology and pathogenesis are still unclear, and it is easy to be misdiagnosed as epilepsy clinically. This article reports a 43-year-old male patient with late-onset mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes (MELAS) confirmed by genetic testing. During hospitalization, he suddenly developed episodic involuntary limb movements, profuse sweating, tachycardia, and arterial hypertension. He was initially diagnosed with symptomatic epilepsy, but long-term electroencephalogram monitoring showed no synchronized discharge, and he was given antiepileptic drugs. The treatment was also ineffective. Brain magnetic resonance imaging revealed a new lesion in the left insular and insular operculum. Dexmedetomidine, baclofen, and gabapentin were given to suppress sympathetic nerve excitability. Drugs were effective, so the diagnosis was corrected to PSH. There is no report of MELAS complicated with PSH in the previous literature. It is speculated that it may be related to the low clinical cognition of PSH. In this case, new lesions in the insula and insular operculum appeared during the onset of PSH, suggesting that may be related to the pathogenesis of PSH.