Theodoropoulos D S, Shawker T H, Heinrichs C, Gahl W A
Human Genetics Branch, NICHD, National Institutes of Health, Bethesda, Maryland 20892, USA.
Pediatr Nephrol. 1995 Aug;9(4):412-8. doi: 10.1007/BF00866713.
Children with nephropathic cystinosis excrete large amounts of calcium and phosphate due to renal tubular Fanconi syndrome, and also receive substantial supplements of phosphate and alkalinizing agents. Since these constitute risk factors for nephrocalcinosis, we evaluated 41 children age 2 months to 15 years with nephropathic cystinosis and good renal function by performing retroperitoneal ultrasound examinations in a blinded fashion. We also retrospectively analyzed parameters of calcium and phosphate metabolism representing 216 person-years of data on these children. Fifteen children had no evidence of medullary nephrocalcinosis, while 18 had mild nephrocalcinosis, and 8 severe nephrocalcinosis; 5 had renal stones. Mean urine calcium and phosphate concentrations increased from 1.47 mM and 5.30 mM, respectively, in children without nephrocalcinosis to 1.60 mM and 5.69 mM in children with mild nephrocalcinosis to 1.66 mM and 6.19 mM in children with severe nephrocalcinosis. Mean urine pH ranged from 7.5 to 8.1. The mean (+/- SD) age of the 26 patients with nephrocalcinosis was 9.4 +/- 3.8 years compared with 5.1 +/- 3.8 years for those without nephrocalcinosis (P < 0.005). Serum calcium, phosphate, vitamin D, and parathyroid hormone did not correlate with frequency or degree of nephrocalcinosis. We conclude that nephrocalcinosis frequently accompanies nephropathic cystinosis, can be detected by ultrasound examination, and might be managed by reducing oral replacement of phosphate, calcium, vitamin D, and citrate. Consideration should be given to truncating phosphate replacement once bone growth ceases.
患有肾病型胱氨酸病的儿童由于肾小管性范科尼综合征会排泄大量钙和磷，并且还会大量补充磷和碱化剂。由于这些因素构成了肾钙质沉着症的风险因素，我们以盲法对41名年龄在2个月至15岁、患有肾病型胱氨酸病且肾功能良好的儿童进行了腹膜后超声检查。我们还回顾性分析了代表这些儿童216人年数据的钙和磷代谢参数。15名儿童没有髓质肾钙质沉着症的证据，18名有轻度肾钙质沉着症，8名有重度肾钙质沉着症；5名有肾结石。无肾钙质沉着症儿童的尿钙和磷平均浓度分别为1.47 mM和5.30 mM，轻度肾钙质沉着症儿童为1.60 mM和5.69 mM，重度肾钙质沉着症儿童为1.66 mM和6.19 mM。尿pH平均值在7.5至8.1之间。26名有肾钙质沉着症患者的平均（±标准差）年龄为9.4±3.8岁，而无肾钙质沉着症患者为5.1±3.8岁（P<0.005）。血清钙、磷、维生素D和甲状旁腺激素与肾钙质沉着症的频率或程度无关。我们得出结论，肾钙质沉着症常伴随肾病型胱氨酸病出现，可通过超声检查检测到，并且可通过减少磷、钙、维生素D和柠檬酸盐的口服补充来处理。一旦骨骼生长停止，应考虑停止补充磷。
