Supplementary Material for: Severe Exertional Heat Stroke with Intestinal Edema and Concurrent Hippocampal Abnormal Signals and Lacunar Infarction: A Case Report

Background
Heat stroke is a life-threatening condition characterized by hyperthermia and central nervous system (CNS) dysfunction, and often leads to multiorgan damage. Both intestinal and neurological complications have been individually reported in severe cases of exertional heat stroke (EHS); however, their concurrent presentation is rare.
Case Presentation
We hereby report the case of a 48-year-old man with a history of untreated hypertension, who collapsed when working outdoors in hot and humid weather. He was brought in a comatose condition with hypotension and a core body temperature of 40.6°C. Initial whole-body computed tomography revealed intestinal edema. Brain computed tomography indicated no abnormalities; however, magnetic resonance imaging on Day 3 revealed diffusion-weighted imaging (DWI) hyperintensities in the bilateral hippocampi and right putamen, consistent with hippocampal ischemia and lacunar infarction. Cognitive assessments using the Mini-Mental State Examination (MMSE), Frontal Assessment Battery (FAB), and Trail Making Test (TMT) identified persistent memory impairment and executive dysfunction. These findings correlated with the magnetic resonance imaging (MRI) report and corroborated the hippocampal and frontal-subcortical involvement. The putaminal infarct was attributed to microvascular vulnerability intensified by dehydration and hypercoagulability.
Conclusion
This is the first reported case of EHS presenting with concurrent intestinal edema, hippocampal abnormalities, and lacunar infarction. Early systemic and neurological imaging, along with detailed neuropsychological assessment, are crucial for identifying the extent of CNS injury. Intestinal edema on early CT imaging may serve as a radiological marker of systemic endothelial injury and potential CNS involvement in severe EHS, thereby alerting clinicians to the possibility of intracranial complications.