Manifestation of Intracranial Lesions at High Altitude: Case Report and Review of the Literature.

Speidel, Victor, Jan Christoph Purrucker, and Katarína Klobučníková. Manifestation of intracranial lesions at high altitude: case report and review of the literature. High Alt Med Biol. 22:87-89, 2021.-A 32-year-old man trekked to the South Everest Base Camp (5,364 m) in Nepal. On the last day of the ascent, he noticed some dysesthesia in his right leg and descended by helicopter. He suffered a generalized seizure shortly after his descent, followed by right-sided hemiparesis and speech arrest. Without the possibility of cerebral imaging, the patient was given dexamethasone intravenously who showed a marked improvement and regained the ability to speak. Magnetic resonance imaging later revealed a lesion in the left frontotemporal region with compression of brain parenchyma and minimal paralesional edema. A meningioma was later surgically resected. Although seizures are a common first manifestation of meningioma, we argue that the exposure to high altitude may have contributed to his symptoms, either by increasing the peritumoral edema by pathophysiology similar to high-altitude cerebral edema (HACE) or lowering the seizure threshold otherwise. This case shows a before unknown pre-existing condition becoming symptomatic at high altitude and illustrates the necessity for careful and immediate evaluation of every patient with new onset of unexplained focal neurological deficits or seizures at high altitude in addition to unspecific neurological symptoms commonly associated with HACE such as headaches, dizziness, lightheadedness, or ataxia.