Department of Surgery, University of Pittsburgh, PA.
Department of Surgery, University of Pittsburgh, PA; Division of Endocrine Surgery, University of Pittsburgh, PA.
Surgery. 2022 Jan;171(1):17-22. doi: 10.1016/j.surg.2021.04.055. Epub 2021 Jul 27.
Primary hyperparathyroidism and familial hypocalciuric hypercalcemia have similar biochemical profiles, and calcium-to-creatinine-clearance ratio helps distinguish the two. Additionally, 24-hour urine calcium >400 mg/day indicates surgery and guidelines recommend obtaining 24-hour urine calcium preoperatively. Our aim was to assess how 24-hour urine calcium altered care in the evaluation of suspected primary hyperparathyroidism.
Consecutive patients assessed for primary hyperparathyroidism from 2018 to 2020 were reviewed. Primary hyperparathyroidism was diagnosed by 2016 American Association of Endocrine Surgeons Parathyroidectomy Guidelines criteria. 24-hour urine calcium-directed change in care was defined as familial hypocalciuric hypercalcemia diagnosis, surgical deferment for additional testing, or 24-hour urine calcium >400 mg/day as the sole surgical indication.
Of 613 patients, 565 (92%) completed 24-hour urine calcium and 477 (84%) had concurrent biochemical testing to calculate calcium-to-creatinine-clearance ratio. 24-hour urine calcium was <100 mg/day in 9% (49/565) and calcium-to-creatinine-clearance ratio was <0.01 in 17% (82/477). No patient had confirmed familial hypocalciuric hypercalcemia, although 1 had a CASR variant of undetermined significance. When calcium-to-creatinine-clearance ratio was <0.01, familial hypocalciuric hypercalcemia was excluded by 24-hour urine calcium >100 mg/day (56%), prior normal calcium (16%), renal insufficiency (11%), absence of familial hypercalcemia (3%), normal repeat 24-hour urine calcium (10%), or interfering diuretic (1%). 24-hour urine calcium-directed change in care occurred in 25 (4%), including 4 (1%) who had genetic testing. Four-gland hyperplasia was more common with calcium-to-creatinine-clearance ratio <0.01 (17% vs calcium-to-creatinine-clearance ratio ≥ 0.01, 4%, P < .001), but surgical failure rates were equivalent (P = .24).
24-hour urine calcium compliance was high, and results affected management in 4%, including productive identification of hypercalciuria as the sole surgical indication in 2 patients. When calcium-to-creatinine-clearance ratio <0.01, clinical assessment was sufficient to exclude familial hypocalciuric hypercalcemia and only 1% required genetic testing. 24-hour urine calcium should be ordered judiciously during primary hyperparathyroidism assessment.
原发性甲状旁腺功能亢进症和家族性低钙血症性高钙血症的生化表现相似，钙与肌酐清除率比值有助于区分两者。此外，24 小时尿钙>400mg/天提示手术，指南建议术前获得 24 小时尿钙。我们的目的是评估 24 小时尿钙如何改变原发性甲状旁腺功能亢进症评估中的治疗方法。
回顾了 2018 年至 2020 年连续评估原发性甲状旁腺功能亢进症的患者。原发性甲状旁腺功能亢进症的诊断符合 2016 年美国内分泌外科学会甲状旁腺切除术指南标准。24 小时尿钙指导的治疗方法改变定义为家族性低钙血症性高钙血症诊断、为进一步检查推迟手术或仅 24 小时尿钙>400mg/天作为唯一手术指征。
613 例患者中，565 例（92%）完成了 24 小时尿钙检查，477 例（84%）同时进行了生化检查以计算钙与肌酐清除率比值。9%（49/565）的患者 24 小时尿钙<100mg/天，17%（82/477）的患者钙与肌酐清除率比值<0.01。虽然 1 例患者存在 CASR 意义未明的变异，但无患者确诊为家族性低钙血症性高钙血症。当钙与肌酐清除率比值<0.01 时，通过 24 小时尿钙>100mg/天（56%）、既往正常钙（16%）、肾功能不全（11%）、无家族性高钙血症（3%）、正常重复 24 小时尿钙（10%）或干扰性利尿剂（1%）排除家族性低钙血症性高钙血症。25 例（4%）患者的治疗方法发生了 24 小时尿钙指导的改变，包括 4 例（1%）患者进行了基因检测。钙与肌酐清除率比值<0.01 时，四腺增生更为常见（17%比钙与肌酐清除率比值≥0.01，4%，P<0.001），但手术失败率相当（P=0.24）。
24 小时尿钙的依从性较高，结果影响了 4%患者的治疗，包括 2 例患者仅通过高钙尿症作为唯一手术指征进行了有效的识别。当钙与肌酐清除率比值<0.01 时，临床评估足以排除家族性低钙血症性高钙血症，仅 1%的患者需要基因检测。在原发性甲状旁腺功能亢进症评估期间，应慎重进行 24 小时尿钙检查。
