Misleading Serum Procalcitonin Elevation in Heatstroke

A healthy 44-year-old man, with a typical presentation of exertional heatstroke, presented with an increase in serum procalcitonin (PCT) levels. Suspecting a coexisting infection, the emergency physician started empirical antibiotic treatment and obtained samples for culture. The antibiotic treatment was stopped immediately after ward admission due to lack of signs of infection. The patient recovered completely after several days of rehydrating therapy and cultures remained negative for bacterial growth. PCT elevation is typically found with heatstroke, but this association is rarely found in daily practice due to the futility of PCT testing in this situation. Increased serum PCT levels in the context of heatstroke must not lead to an unsupported alternative diagnosis and useless investigations, tests and treatment. LEARNING POINTS: Elevated serum procalcitonin (PCT) levels are typical in heatstroke, although the association of PCT with heatstroke is rarely noted in clinical practice. A typical heatstroke scenario is enough to explain the increase in procalcitonin levels, and must not lead to inappropriate alternative diagnoses, investigations and treatments.