Renal calculus is a common disease with complex etiology and high recurrence rate. Recent studies have revealed that gene mutations may lead to metabolic defects which are associated with the formation of renal calculus, and single gene mutation is involved in relative high proportion of renal calculus. Gene mutations cause changes in enzyme function, metabolic pathway, ion transport, and receptor sensitivity, causing defects in oxalic acid metabolism, cystine metabolism, calcium ion metabolism, or purine metabolism, which may lead to the formation of renal calculus. The hereditary conditions associated with renal calculus include primary hyperoxaluria, cystinuria, Dent disease, familial hypomagnesemia with hypercalciuria and nephrocalcinosis, Bartter syndrome, primary distal renal tubular acidosis, infant hypercalcemia, hereditary hypophosphatemic rickets with hypercalciuria, adenine phosphoribosyltransferase deficiency, hypoxanthine-guanine phosphoribosyltransferase deficiency, and hereditary xanthinuria. This article reviews the research progress on renal calculus associated with inborn error of metabolism, to provide reference for early screening, diagnosis, treatment, prevention and recurrence of renal calculus.
Infant ; Humans ; Hypercalciuria/genetics* ; Kidney Calculi/genetics* ; Urolithiasis/genetics* ; Nephrocalcinosis/genetics* ; Metabolism, Inborn Errors/genetics*

Idiopathic infantile hypercalcemia is characterized by hypercalcemia, dehydration, vomiting, and failure to thrive, and it is due to mutations in 24-hydroxylase (CYP24A1). Recently, mutations in sodium-phosphate cotransporter (SLC34A1) expressed in the kidney were discovered as an additional cause of idiopathic infantile hypercalcemia. This report describes a female infant admitted for evaluation of nephrocalcinosis. She presented with hypercalcemia, hypercalciuria, low intact parathyroid hormone level, and high 1,25-dihydroxyvitamin D3 level. Exome sequencing identified novel compound heterozygous mutations in SLC34A1 (c.1337G>A, c.1483C>T). The patient was treated with fluids for hydration, furosemide, a corticosteroid, and restriction of calcium/vitamin D intake. At the age of 7 months, the patient's calcium level was within the normal range, and hypercalciuria waxed and waned. Renal echogenicity improved on the follow-up ultrasonogram, and developmental delay was not noted. In cases of hypercalcemia with subsequent hypercalciuria, DNA analysis for SLC34A1 gene mutations and CYP24A1 gene mutations should be performed. Further studies are required to obtain long-term data on hypercalciuria and nephrocalcinosis.
Calcitriol ; Calcium ; Dehydration ; DNA ; Exome ; Failure to Thrive ; Female ; Follow-Up Studies ; Furosemide ; Humans ; Hypercalcemia ; Hypercalciuria ; Hypophosphatemia ; Infant ; Kidney ; Nephrocalcinosis ; Parathyroid Hormone ; Reference Values ; Sodium-Phosphate Cotransporter Proteins ; Ultrasonography ; Vitamin D ; Vitamin D3 24-Hydroxylase ; Vomiting

PURPOSE: Urinary calcium creatinine ratio (UCaCrR) is a reliable indicator for monitoring hypercalciuria following vitamin D supplementation. However, the reference range varies from region to region. Previous studies did not take vitamin D and parathyroid hormone status into account while evaluating UCaCrR. Hence, we undertook this study to establish the 95th percentile of UCaCrR as an indicator of hypercalciuria in North Indian children and adolescents. METHODS: Four hundred seventy-three participants (boys 62.2%, girls 37.8%) with adequate dietary calcium intake, normal serum levels of 25-hydroxy-vitamin D (>20 ng/mL), and without secondary hyperparathyroidism following supplementation were selected for evaluation of UCaCrR. RESULTS: The mean age and body mass index of subjects were 11.2±2.6 years and 18.0±3.6 kg/m2, respectively. The 95th percentile of UCaCrR in the study population was 0.126. The mean, median, and 95th percentile of UCaCrR was significantly higher in prepubertal children (age ≤10 years) (0.0586±0.0374, median=0.0548, 95th percentile=0.136) compared to those >10 years old (0.0503±0.0363, median=0.0407, 95th percentile=0.123, P=0.02). No significant difference in UCaCrR was observed between genders and different weight categories. CONCLUSIONS: UCaCrR of 0.13 defines the cutoff value for hypercalciuria in North Indian children and adolescents with adequate dietary intake of calcium and sufficient serum vitamin D levels.
Adolescent ; Body Mass Index ; Calcium ; Calcium, Dietary ; Child ; Creatinine ; Female ; Humans ; Hypercalciuria ; Hyperparathyroidism, Secondary ; Parathyroid Hormone ; Reference Values ; Vitamin D

PURPOSE: It is well known that obesity is related to vitamin D deficiency (VDD). We investigated the response to vitamin D replacement in normal-weight and overweight children. METHODS: This was a prospective study including 62 Korean children with VDD. VDD was defined as a serum 25-hydroxycholecalciferol (25(OH)D) concentration <20 ng/mL. Overweight was defined as a body mass index (BMI)≥the 85th percentile (n=21), and normal weight as a BMI between the 5th and 84th percentiles (n=41). All participants received vitamin D3 supplementation (2,000 IU/day) for 8 weeks. The serum levels of 25(OH)D, PTH and biochemical parameters were measured before and after treatment. RESULTS: The mean age was 10.0±1.4 years in normal-weight children and 10.0±2.1 years in overweight children (P=0.93). After 8 weeks of treatment, 61.9% of normal-weight children and 47.6% of overweight children achieved vitamin D sufficiency (P =0.30). The mean serum 25(OH)D levels after vitamin D replacement were 33.8±7.6 ng/mL and 30.3±6.6 ng/mL in normal-weight and overweight children, respectively (P =0.10). The mean calcium/creatinine ratios after treatment were 0.09±0.07 and 0.08±0.06 in the normal-weight and overweight groups, respectively, and no hypercalciuria was found. In multiple regression analysis, the response to vitamin D replacement was influenced by the BMI (β=-1.0, P=0.03) and sex (β=-4.0, P=0.04). CONCLUSIONS: Eight weeks of vitamin D replacement (2,000 IU/day) is sufficient to overcome vitamin D deficiency in normal-weight and overweight children without any complications.
Body Mass Index ; Calcifediol ; Child ; Cholecalciferol ; Humans ; Hypercalciuria ; Obesity ; Overweight ; Prospective Studies ; Vitamin D Deficiency ; Vitamin D ; Vitamins

PURPOSE: The association between hypercalciuria and febrile convulsion is controversial. The present study aimed to investigate the statistical association between hypercalciuria and childhood febrile convulsions. METHODS: Overall, 160 children aged 6 months to 5 years, including 80 children with febrile convulsion and 80 febrile children without convulsion (comparison group), were recruited. All laboratory tests, including 24-hour urine calcium, were undertaken in an academic clinical laboratory. RESULTS: Forty-five children of the febrile convulsion group (60%) and 30 of the comparison group (40%) had hypercalciuria. There was a significant difference between the 2 groups (P=0.02). CONCLUSION: Our results indicated that there is a statistical association between convulsion and hypercalciuria in children. Since we found this association with a cross-sectional assessment, further studies, especially prospective and controlled designs, are needed.
Calcium ; Child* ; Humans ; Hypercalciuria* ; Prospective Studies ; Seizures ; Seizures, Febrile*

Autosomal-dominant hypocalcemia with hypercalciuria (ADHH) is a genetic disease characterized by hypoparathyroidism with hypercalciuria. Most patients with ADHH have calcium-sensing receptor (CaSR) gene mutations. The CaSR gene controls parathyroid secretions, and mutations in this gene can be detected via changes in serum calcium level. The activating mutation of the CaSR gene results in familial or sporadic ADHH. Most activating mutations of the CaSR gene are reportedly de novo missense mutations. This is the first case report of a novel activating variant of the CaSR gene in a neonate with congenital hypoparathyroidism with hypomagnesemia and hypercalciuria. We also report the 3-month follow-up management of the patient.
Calcium ; Follow-Up Studies ; Humans ; Hypercalciuria ; Hypocalcemia ; Hypoparathyroidism* ; Infant, Newborn* ; Mutation, Missense ; Receptors, Calcium-Sensing

BACKGROUND: Increasing evidence supports interplay between aldosterone and parathyroid hormone (PTH), which may aggravate cardiovascular complications in various heart diseases. Negative structural cardiovascular remodeling by primary aldosteronism (PA) is also suspected to be associated with changes in calcium levels. However, to date, few clinical studies have examined how changes in calcium and PTH levels influence cardiovascular outcomes in PA patients. Therefore, we investigated the impact of altered calcium homeostasis caused by excessive aldosterone on cardiovascular parameters in patients with PA. METHODS: Forty-two patients (mean age 48.8±10.9 years; 1:1, male:female) whose plasma aldosterone concentration/plasma renin activity ratio was more than 30 were selected among those who had visited Severance Hospital from 2010 to 2014. All patients underwent adrenal venous sampling with complete access to both adrenal veins. RESULTS: The prevalence of unilateral adrenal adenoma (54.8%) was similar to that of bilateral adrenal hyperplasia. Mean serum corrected calcium level was 8.9±0.3 mg/dL (range, 8.3 to 9.9). The corrected calcium level had a negative linear correlation with left ventricular end-diastolic diameter (LVEDD, ρ=−0.424, P=0.031). Moreover, multivariable regression analysis showed that the corrected calcium level was marginally associated with the LVEDD and corrected QT (QTc) interval (β=−0.366, P=0.068 and β=−0.252, P=0.070, respectively). CONCLUSION: Aldosterone-mediated hypercalciuria and subsequent hypocalcemia may be partly involved in the development of cardiac remodeling as well as a prolonged QTc interval, in subjects with PA, thereby triggering deleterious effects on target organs additively.
Adenoma ; Aldosterone ; Calcium* ; Heart Diseases ; Homeostasis ; Humans ; Hyperaldosteronism* ; Hypercalciuria ; Hyperplasia ; Hypocalcemia ; Metabolism* ; Parathyroid Hormone ; Plasma ; Prevalence ; Renin ; Veins

The incidence of kidney stones is common in the United States and treatments for them are very costly. This review article provides information about epidemiology, mechanism, diagnosis, and pathophysiology of kidney stone formation, and methods for the evaluation of stone risks for new and follow-up patients. Adequate evaluation and management can prevent recurrence of stones. Kidney stone prevention should be individualized in both its medical and dietary management, keeping in mind the specific risks involved for each type of stones. Recognition of these risk factors and development of long-term management strategies for dealing with them are the most effective ways to prevent recurrence of kidney stones.
Calcium Oxalate ; Diagnosis ; Epidemiology ; Humans ; Hypercalciuria ; Hyperoxaluria ; Incidence ; Kidney Calculi* ; Kidney* ; Nephrolithiasis ; Recurrence ; Risk Factors ; United States

Type I (distal) renal tubular acidosis (RTA) is a disorder associated with the failure to excrete hydrogen ions from the distal renal tubule. It is characterized by hyperchloremic metabolic acidosis, an abnormal increase in urine pH, reduced urinary excretion of ammonium and bicarbonate ions, and mild deterioration in renal function. Hypercalciuria is common in distal RTA because of bone resorption, which increases as a buffer against metabolic acidosis. This can result in intractable rickets. We describe a case of distal RTA with nephrocalcinosis during follow-up of rickets in a patient who presented with clinical manifestations of short stature, failure to thrive, recurrent vomiting, dehydration, and irritability.
Acidosis ; Acidosis, Renal Tubular* ; Bicarbonates ; Bone Resorption ; Dehydration ; Failure to Thrive ; Follow-Up Studies ; Humans ; Hydrogen-Ion Concentration ; Hypercalciuria ; Kidney Tubules, Distal ; Nephrocalcinosis ; Protons ; Quaternary Ammonium Compounds ; Rickets* ; Vomiting

BACKGROUND: Hypercalciuria is one of the most common causes of unexplained isolated hematuria. The diagnostic methods for hypercalciuria have not yet been standardized. The aim of this study was to assess whether random urinary calcium/creatinine ratio could be used as a screening tool for hypercalciuria in children with hematuria. METHODS: This prospective study included 264 children with primary hematuria for whom both random and 24 hr urinary evaluations were performed. Pearson correlation and ROC curve were used to assess the correlations. A multiple linear regression model was used to analyze effects of age, weight, height, body mass index, and body surface area on random urinary calcium/creatinine ratio. RESULTS: There was a moderately strong correlation between random urinary calcium/creatinine ratio and 24 hr urinary calcium excretion (r=0.584, P<0.001). The most appropriate cutoff value of random urinary calcium/creatinine ratio for the estimation of hypercalciuria was 0.075 mg/mg (sensitivity, 77.8%; specificity, 64.3%; area under the curve, 0.778). Body mass index and 24 hr urinary calcium excretion significantly affected random urinary calcium/creatinine ratio with a low coefficient of determination (r2=0.380, P<0.001). CONCLUSIONS: Random urinary calcium/creatinine ratio is not suitable for screening hypercalciuria in children with hematuria. Twenty-four hour urinary analysis should be performed to diagnose hypercalciuria in children with hematuria.
Adolescent ; Area Under Curve ; Body Mass Index ; Calcium/*urine ; Child ; Child, Preschool ; Creatinine/*urine ; Female ; Hematuria/*complications ; Humans ; Hypercalciuria/*complications/*diagnosis ; Linear Models ; Male ; Prospective Studies ; ROC Curve ; Sensitivity and Specificity