Introduction: Hypocalcemia is a common and poorly understood finding in critically ill patients. The current
study was designed to assess the association of ionized calcium, vitamin D, phosphorus and Parathyroid hormone levels in
a cohort of patients with and without kidney dysfunction admitted for sepsis or non-infectious causes.
Methods: Prospective cohort clinical and biochemical study.
Results: We confirmed that hypocalcemia and hypovitaminosis D are a common finding in critically ill patients.
Parathyroid hormone levels significantly rise in septic shock. In the recovery phase, however, despite persistent
hypocalcemia, Parathyroid hormone levels abruptly decrease in patients with kidney dysfunction, but not in patients with
normal renal function.
Conclusions: The systemic inflammatory response syndrome probably leads to inappropriately high Parathyroid hormone
levels during septic shock. In the recovery phase, Parathyroid hormone levels decrease, but calcium levels remain low,
displaying evidence that the parathyroid is not responding as expected.
Since Parathyroid hormone receptors and calcium-sensing receptors have been described in immune cells and other cell
types, we propose that these effects may have a plethora of other deleterious effects, with important implications to the
pathogenesis of septic shock.