Hypercalcitoninemia, hypocalcemia, and toxic shock syndrome

Toxic shock syndrome is a multisystem illness frequently complicated by hypocalcemia. The etiology of the hypocalcemia, which may be severe, is not well understood. We report two cases of fatal toxic shock syndrome accompanied by severe hypocalcemia; each patient also had an inappropriately elevated serum calcitonin level, which in one case was as high as 179,000 pg/mL. Hypercalcitoninemia may be a cause of the low serum calcium levels as well as of certain clinical manifestations of toxic shock syndrome.