A patient has a total calcium of 7.6 mg per deciliter and an albumin of 2.0 g per deciliter. How should this result be interpreted?
1True hypocalcemia requiring immediate intravenous calcium replacement and monitoring
2The total calcium is decreased because of the low albumin, and the corrected value is near normal✓ 정답
3The result indicates primary hyperparathyroidism and further parathyroid hormone testing is needed
4The specimen must be recollected because the value is not interpretable
해설
A large fraction of calcium circulates bound to albumin, so a low albumin lowers the total calcium even when the physiologically active ionized calcium is normal. Adding approximately 0.8 mg/dL to the total calcium for every 1 g/dL decrease in albumin brings the value near normal. Do not diagnose hypocalcemia without this correction.