The mechanism of hypophosphatemia in acute heat stroke.

Severe heat stroke may be associated with hypophosphatemia and hypocalcemia. Hypophosphatemia is generally observed within hours after onset, but hypocalcemia usually occurs on the second or third day, and after hypophosphatemia has undergone spontaneous correction. A young man displayed respiratory alkalosis during the course of severe heat stroke. The hypophosphatemia abated spontaneously as metabolic acidosis and acute renal failure supervened. Hypocalcemia became prominent and was more severe than that ascribable to uremia. Hypocalcemia was probably the result of calcium phosphate and calcium carbonate deposition in injured skeletal muscle.