Abstract
Heat-related illness (HRI) represents a growing public health challenge in the context of global warming. Ranging from mild symptoms such as heat cramps to life-threatening heatstroke, HRI requires prompt recognition and appropriate management to reduce morbidity and mortality. The diagnosis of HRI is primarily based on clinical symptoms but is supported by laboratory evaluation, especially in severe cases. Heatstroke, the most critical form, is defined by core body temperature ≥ 40°C and central nervous system dysfunction. In addition to conventional laboratory markers, recent advances in molecular biology have identified several biomarkers, such as heat shock proteins, HMGB1 (High Mobility Group Box 1), and mitochondrial DNA, which may improve early and accurate detection and prognostication. This review summarizes the diagnostic approach to HRI, highlighting key clinical findings, laboratory assessments, and emerging molecular markers.