• Childhood Kidney Diseases
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• v.26 no.1
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• pp.63-67
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• 2022

Nephrocalcinosis often occurs in infants and is caused by excessive calcium or vitamin D supplementation, neonatal primary hyperparathyroidism, and genetic disorders. Idiopathic infantile hypercalcemia (IIH), a rare cause of nephrocalcinosis, results from genetic defects in CYP24A1 or SLC34A1. Mutations in CYP24A1, which encodes 25-hydroxyvitamin D 24-hydroxylase, disrupt active vitamin D degradation. IIH clinically manifests as failure to thrive and hypercalcemia within the first year of life and usually remits spontaneously. Herein, we present a case of IIH wih CYP24A1 mutations. An 11-month-old girl visited our hospital with incidental hypercalcemia. She showed failure to thrive, and her oral intake had decreased over time since the age of 6 months. Her initial serum parathyroid hormone level was low, 25-OH vitamin D and 1,25(OH)₂ vitamin D levels were normal, and renal ultrasonography showed bilateral nephrocalcinosis. Whole-exome sequencing revealed compound heterozygous variants in CYP24A1 (NM_000782.4:c.376C>T [p.Pro126Ser] and c.1310C>A [p.Pro437His]). Although her hypercalcemia and poor oral intake spontaneously resolved in approximately 8 months, we suggested that her nephrocalcinosis and renal function be regularly checked in consideration of potential asymptomatic renal damage. Hypercalcemia caused by IIH should be suspected in infants with severe nephrocalcinosis, especially when presenting with failure to thrive.

• Childhood Kidney Diseases
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• v.7 no.2
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• pp.234-238
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• 2003

Fanconi syndrome is a generalized functional disorder of the proximal tubule of the kidney and is characterized by aminoaciduria, glycosuria, hyperphosphaturia, dehydration, rickets, and growth failure. Nephrocalcinosis and hypercalciuria are rare manifestations of Fanconi syndrome. There is no case report of Fanconi syndrome complicated with nephrocalcinosis and hypercalciuria in Korea. A 6-year-old boy presented with genu valgum and waddling gaits for about 3 years. There was no family history of renal disease and his physical examination was normal except for genu valgum and corrected cleft lip and palate. Laboratory investigations showed generalized aminoaciduria, glycosuria, hyperphosphaturia, hypercalciuria, and low-molecular weight proteinuria including ${\beta}$-microglobulin. Serum 25-OH vitamin $D_3$ was within the normal range, and $1,25-(OH)_2$ vitamin $D_3$ was elevated. Bilateral renal medullary hyperechogenicity was demonstrated by ultrasonography. Analysis of the CLCN5 gene revealed no mutation. Here we describe a boy with Fanconi syndrome complicated with nophrocalcinosis and discuss the differential diagnosis.

• Childhood Kidney Diseases
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• v.6 no.2
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• pp.259-265
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• 2002

Bartter syndrome is a rare disorder characterized by the association of hypokalemic hypochloremic metabolic alkalosis, hyperreninemia, hyperaldosteronemia, short stature and nephrocalcinosis. This disorder presents with hyperplasia of juxtaglomerular apparatus on renal biopsy. We experienced a case of late-onset Bartter syndrome with nephrocalcinosis in a 9-year-old boy, whose chief pictures were muscle weakness, short stature, persistent sterile pyuria and microscopic hematuria. We report this case with a brief review of related literatures.

• Journal of Yeungnam Medical Science
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• v.31 no.1
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• pp.21-24
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• 2014

Clinical presentation of Bartter syndrome is similar to surrepitious vomiting or use of diuretics. Therefore, precise differential diagnosis of Bartter syndrome is crucial. We report a case of medullary nephrocalcinosis (MNC) induced by furosemide mimicking Bartter syndrome. A 55-year-old female patient visited our hospital with renal dysfunction on basis of hypokalemia and metabolic alkalosis. She had no history of hypertension or drug use except allopurinol and atorvastatin. She did not complain of nausea or vomiting on presentation and the serum magnesium level was normal. We performed ultrasonography, that showed MNC. For these reasons, we suspected Bartter syndrome and corrected the electrolyte imbalance. During outpatient follow up, we found that the patient had been taking 400 mg of furosemide daily for 30 years. We could diagnose furosemide induced MNC, and recommended to her to reduce the amount of furosemide.

• Journal of the korean academy of Pediatric Dentistry
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• v.47 no.3
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• pp.344-351
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• 2020

Amelogenesis imperfecta (AI) occurs either in isolation or in association with other dental abnormalities and systemic disorder. A rare syndrome associating AI with nephrocalcinosis was named as Enamel Renal Syndrome (ERS; OMIM #204690). This syndrome is characterized by severe enamel hypoplasia, failed tooth eruption, intra pulpal calcifications, enlarged gingiva, and nephrocalcinosis. Nephrocalcinosis is a condition where calcium salts are deposited in renal tissue, and this may lead to critical kidney complications. This rare syndrome shows pathognomonic oral characteristics that are easily detectable at an early age, which proceeds the onset of renal involvement. Pediatric dentists are the first oral health practitioners whom ERS patients will meet at early age. The role of pediatric dentists is critically important for early diagnosis and referral of patients to both nephrologists for renal assessment and geneticists for identification of causative mutation and diagnosis. Early detection of renal involvement may provide chances to prevent further undesired renal complications.

• Childhood Kidney Diseases
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• v.6 no.2
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• pp.266-271
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• 2002

There are several diseases characterized by neurologic abnormalities and renal disease. Joubert syndrome is one of them. Joubert syndrome Is a relatively rare autosomal recessive syndrome. The most significant and constant neurologic finding is hypoplasia of the cerebellar vermis. Joubert syndrome is associated with hypotonia, retinal dystrophy, abnormal eye movement, delayed development, abnormal respiratory pattern (neonatal episodic tachypnea or apnea) and nephronophthisis. We report a boy with Joubert syndrome associated with nephrocalcinosis and agenesis of the cerebellar vermis. This patient had also abnormal eye movement, hypotonia, abnormal respiratory pattern, delayed development and chronic renal failure.

• Journal of Nutrition and Health
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• v.33 no.2
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• pp.147-157
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• 2000

This study examined the effects of excess intake of calcium (Ca) and iron (Fe) supplement on bone loss, nephrocalcinosis and renal function in osteoporotic model rats. Seven-week-old female rats were first fed a Ca-deficient diet for four weeks after ovariectomy operation, and then one of nine experimental diets for additional eight weeks, containing three levels of Ca, normal (0.5%) or high (1.5%) or excess (2.5%) and three levels of Fe, normal (35ppm) or high (210ppm) or excess (350ppm). The osteoporotic model rats showed a remarkable increase in body weight, serum alkaline phosphatase (ALP) and decrease in breaking force, Ca, P, Mg contents of femur. Serum Ca concentration was not significantly affected by dietary Ca and Fe levles. Liver Ca content increased in rats fed a high-and excess-Ca diet. Kidney Ca content and microscopic Ca deposition remarkably increased in osteoporotic model rats compared to control group, and showed a tendency to decrease in rats fed a excess-Ca diet. Breaking force of femur increased with increasing dietary Ca levels, but Ca, P contents of femur and serum ALP were not significantly affected by dietary Ca and Fe levels. Serum total protein decreased in rats fed a excess-Ca diet, BUN increased in rats fed a excess-Ca diet, while serum uric acid and creatinine were not significantly affected by dietary Ca levels. Urinary creatinine, GFR increased in rats fed a high-and excess-Ca, diet, and GFR was highest in rats fed a excess-Ca/excess-Fe diet. These results suggest that excess intake of Ca may increase breaking force of femur, but not increase mineral contents of femur, and decrease kidney function. Furthermore, excess intake of Fe and Ca concurrently may aggravate kidney function leading to potential health problems in ovariectomized osteoporotic model rats.

• Childhood Kidney Diseases
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• v.8 no.1
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• pp.57-62
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• 2004

Schinzel-Giedion syndrome is a rare, distinct dysmorphic syndrome characterized by congenital hydronephrosis, skeletal dysplasia, and severe developmental retardation, likely to be inherited as an autosomal recessive trait, but not yet confirmed. This syndrome is characterized by coarse facial features such as midfacial retraction, bulging forehead, short nose with anteverted nostrils, low-set malformed ears, protruding large tongue, and hypertelorism. Skeletal and limb defects, choanal stenosis, simian creases, hypospadias, microphallus, hypertrichosis, and intractable seizures are the frequently associated clinical findings. Urogenital involvement is a major component of the syndrome, and this problem sometimes is associated with nephrocalcinosis and urinary tract infection in the clinical course of the disease. We report a 22 month-old girl with Schinzel-Giedion syndrome complicated by medullary nephrocalcinosis and urinary tract infection due to Klebsiella pneumoniae. This patient had also been suffering from postnatal growth deficiency, intractable seizure, spastic tetraplegia, delayed development and severe mental retardation.

• Childhood Kidney Diseases
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• v.26 no.2
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• pp.80-85
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• 2022

Purpose: To determine the prevalence, clinical manifestations, and outcomes of renal involvements in pediatric Alagille syndrome (ALGS). Methods: A total of 21 patients diagnosed with ALGS at age under 18 years who visited Samsung Medical Center from March 1999 to March 2022 were enrolled. ALGS was diagnosed either by clinical manifestations, targeted JAG1 sequencing, and/or liver biopsy. Medical records including sex, age, renal manifestations, urinalysis, serum creatinine, JAG1 sequencing, and ultrasonography were retrospectively reviewed. Results: The male to female ratio was 9:12. The mean age of patients at confirmative diagnosis of ALGS was 18.4 months. Sanger sequencing was performed for 17 patients. Sixteen of 21 patients (76.1%) showed JAG1 mutations. Renal involvement was found in 10 patients (47.6%). The most common type of anomaly was renal dysplasia (40%). One patient having renal dysplasia was pathologically confirmed with glomerular lipid deposition. Two patients (20%) manifested nephrocalcinosis/nephrolithiasis. Among eight renal-involved patients who survived, four (50%) progressed to chronic kidney disease stage 3. Two of these chronic kidney disease patients were diagnosed with hepatorenal syndrome. The other four patients had renal functions preserved, including two without any interventions and two who underwent urological interventions. Conclusions: The current study revealed a high prevalence of renal involvement in Korean pediatric ALGS with diverse phenotypes.

• Childhood Kidney Diseases
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• v.9 no.2
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• pp.255-262
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• 2005

Battler and Bartter-like syndromes, which include classic Bartter syndrome(type III), neonatat Bartter syndrome(type I, II or IV) and Gitelman syndrome, are autosomal - recessively inherited renal tubular disorders characterized b)r hypokalemic metabolic alkalosis, salt wasting and normal to low blood pressure. Neonatal Bartter syndrome is characterized by intrauterine polyhydramnios, premature delivery, life-threatening episodes of fever and dehydration, subsequent failure to thrive, and severe hypercalciuria with nephrocalcinosis and osteopenia. It is caused by mutations in NKCC2(type I), ROMK(type II) or BSND(type IV) genes. If diagnosed and treated early, the progression to renal failure can be prevented and catch-up growth and normal development are achieved. We report here a 6 month-old infant with neonatal Bartter syndrome who presented with hypokalemic metabolic alkalosis, polyhydramnios and premature delivery, persistent high fever and dehydration, failure to thrive, hypercalciuria, and nephrocalcinosis. He received indomethacin and potassium chloride per os and show ed catch-up growth and normal developmental profile at 19 months of age. (J Korean Soc Pediatr Nephrol 2005;9:255-262)