PTH and Sepsis: The link between hypocalcemia and sepsis or endotoxemia is not completely understood, but low parathyroid hormone concentrations due to damage to the parathyroid gland or suppression of the gland by cytokines, reduced vitamin D synthesis, sequestration of calcium within the gastrointestinal tract, and calcium chelation with L-lactate are discussed (86, 90, 93–96).