Davidson Peiris Emma, Wusirika Raghav
Department of Medicine, Oregon Health and Science University, Portland, Oregon, USA.
Division of Nephrology and Hypertension, Department of Medicine, Oregon Health and Science University, Portland, Oregon, USA.
Case Rep Nephrol Dial. 2017 Dec 18;7(3):167-171. doi: 10.1159/000485243. eCollection 2017 Sep-Dec.
CYP24A1 is an enzyme that inactivates vitamin D. Loss-of-function mutations in this enzyme are rare but have been linked with idiopathic infantile hypercalcemia as well as adult-onset nephrocalcinosis and nephrolithiasis. Genetic testing for this mutation should be considered in the presence of calciuria, elevated serum calcium, elevated 1,25-dihydroxyvitamin D, and suppressed parathyroid hormone. We present a case with these lab findings as well as an elevated 25-hydroxyvitamin D/24,25-dihydroxyvitamin D ratio in whom compound heterozygous CYP24A1 mutations were found. His hypercalciuria resolved and 1,25-vitamin D level improved with ketoconazole treatment. We suggest that it is clinically important to identify patients with this phenotype as testing and treatment options are available which could reduce progression to chronic kidney disease in this population.
CYP24A1是一种使维生素D失活的酶。该酶的功能丧失突变很少见，但与特发性婴儿高钙血症以及成人期肾钙质沉着症和肾结石有关。在存在高钙尿症、血清钙升高、1,25-二羟基维生素D升高和甲状旁腺激素受抑制的情况下，应考虑对这种突变进行基因检测。我们报告了一例具有这些实验室检查结果以及25-羟基维生素D/24,25-二羟基维生素D比值升高的病例，在该病例中发现了复合杂合性CYP24A1突变。酮康唑治疗后，他的高钙尿症得到缓解，1,25-维生素D水平有所改善。我们认为，识别具有这种表型的患者具有重要临床意义，因为有检测和治疗方案可供选择，这可能会减少该人群发展为慢性肾病的进程。
