Aladjem M, Barr J, Lahat E, Bistritzer T
Department of Pediatrics, Assaf Harofeh Medical Center, Zerifin, Israel.
Pediatrics. 1996 Feb;97(2):216-9.
In previous studies, the oral calcium loading and deprivation test has been used to distinguish between children with renal (fasting) hypercalciuria (RH) and absorptive hypercalciuria (AH).
We evaluated the long-term clinical course of 30 children with idiopathic hypercalciuria and investigated the influence of urinary sodium excretion, as a reflection of its intake, on urinary calcium excretion.
Thirty normocalcemic, normophosphatemic children (21 boys and 9 girls) with urinary calcium to creatinine ratios greater than 0.57 mmol/L/mmol/L ( > 0.21 mg/dL/mg/dL on the three consecutive examinations participated in this study. They were divided according to their responses to calcium deprivation and loading into AH (16 patients) and RH (14 patients).
When restudied 3 to 7 years later, 6 of the 16 children with AH were normocalciuric and three demonstrated characteristics compatible with RH. The remaining seven patients maintained their initial AH pattern. Of the 14 children with RH, four were normocalciuric and four demonstrated AH. The remaining six children maintained their initial RH pattern. A significant positive correlation was observed between urine sodium and calcium excretion in children with AH or RH. Children who were normocalciuric at the second study had significantly lower values of urine sodium excretion when compared with those in whom hypercalciuria persisted.
We suggest that AH and RH constitute a continuum. The change in characteristics observed during the second study suggests that any attempt to divide these patients into two physiologically distinct subtypes may be artificial. The main factor influencing urinary excretion of calcium in our patients seemed to be sodium intake.
在以往的研究中，口服钙负荷及剥夺试验已被用于区分患有肾性（空腹）高钙尿症（RH）和吸收性高钙尿症（AH）的儿童。
我们评估了30例特发性高钙尿症患儿的长期临床病程，并研究了反映钠摄入量的尿钠排泄对尿钙排泄的影响。
30例血钙正常、血磷正常且尿钙与肌酐比值大于0.57 mmol/L/mmol/L（连续三次检查均>0.21 mg/dL/mg/dL）的儿童（21名男孩和9名女孩）参与了本研究。根据他们对钙剥夺和负荷的反应，将他们分为AH组（16例患者）和RH组（14例患者）。
3至7年后再次研究时，16例AH患儿中有6例尿钙正常，3例表现出与RH相符的特征。其余7例患者维持其初始AH模式。14例RH患儿中，4例尿钙正常，4例表现为AH。其余6例患儿维持其初始RH模式。在AH或RH患儿中，尿钠与钙排泄之间存在显著正相关。与高钙尿症持续存在的患儿相比，第二次研究时尿钙正常的患儿尿钠排泄值显著更低。
我们认为AH和RH构成一个连续统一体。第二次研究期间观察到的特征变化表明，将这些患者分为两种生理上不同亚型的任何尝试可能是人为的。在我们的患者中，影响尿钙排泄的主要因素似乎是钠摄入量。
