DOI: 10.1373/clinchem.2016.261024 

A critical value for total calcium was reported on a 68-year-old female patient who was admitted to the emergency department 15 h prior. The patient’s laboratory results were significant for a serum total calcium of 16.8 (8.4 –10.3) mg/dL, which was verified by replicate analysis, and her free calcium concentration of 2.25 (1.12–1.32) mmol/L. The patient’s serum phosphate was low at 0.5 (2.7– 4.5) mg/dL, and her parathyroid hormone (PTH)2 was also suppressed at 6 (15– 65) pg/mL.