Nephrocalcinosis in children who received high-dose vitamin D.

BACKGROUND: Vitamin D supplements are readily available as over-the-counter preparations. However, although rare, cases of vitamin D overdose still occur and are associated with nephrocalcinosis and life-threatening hypercalcemia. Errors in manufacturing of nutritional supplements may be a cause of vitamin D intoxication in children. This study aimed to identify factors associated with vitamin D overdose-related nephrocalcinosis in children due to manufacturing errors in supplements. METHODS: This retrospective study reviewed medical charts of pediatric patients with non-registered supplement-related vitamin D overdose at a tertiary referral hospital between 2006 and 2011. Clinical and laboratory characteristics of patients with or without nephrocalcinosis were evaluated. Receiver operating characteristics curve and area under the receiver operating characteristics curve were used to determine the most predictive value of each characteristic. RESULTS: A total of 44 patients (males: 29; age: 7-62 months) were included. Age ≤ 16.5 months, body weight ≤ 10.25 kg, body height ≤ 78.5 cm, body surface area (BSA) ≤ 0.475 m2, 25-hydroxyvitamin D3 ≥ 143 ng/mL, and calcium ≥ 10.65 mg/dL were predictive of developing nephrocalcinosis with a sensitivity and specificity of > 60%. Univariant analysis revealed that BSA was the most significant anthropometric prognostic factor (odds ratio: 12.09; 95% confidence interval: 2.61-55.72; P = 0.001). CONCLUSIONS: Children with smaller BSAs were more vulnerable to high-dose vitamin D3-related nephrocalcinosis. Physicians and parents should be aware of the potential adverse effects of vitamin D overdose in children. A higher resolution version of the Graphical abstract is available as Supplementary information.

Segmental multicystic dysplastic kidney in children: clinical presentation, imaging finding, management, and outcome.

PURPOSE: The aim of the study was to assess the presentation, imaging findings, management, and outcome of segmental multicystic dysplastic kidney (MCDK) in children. MATERIALS AND METHODS: Six patients with segmental MCDK were diagnosed and observed at our hospital. We reviewed the medical records to collect data on initial symptoms, results of imaging studies, associated urinary tract anomalies, operation, and outcome. RESULTS: Three patients had abnormal prenatal ultrasound and were diagnosed by further postnatal imaging; they were asymptomatic after birth. The other 3 children presented with a renal mass, recurrent urinary tract infection, or urinary incontinence. Five patients had associated ipsilateral or contralateral urinary tract abnormalities, including vesicoureteral reflux, ureterocele, duplex collecting system, ureteropelvic junction stenosis, and ectopic ureter. Lower tract reconstruction was performed in 3, and open biopsy was done in 1 child. None underwent partial or total nephrectomy, and all had involution of the cysts for a mean of 40 months. CONCLUSIONS: Most of the cases occur in the upper pole of a duplex kidney and often involute spontaneously without significant complication. The clinical presentation and imaging findings depend on the associated anomalies and complications. Although the latter may require surgery to resolve, segmental MCDK itself rarely requires resection.

Kimura disease in a patient with renal allograft failure secondary to chronic rejection.

Recent studies suggest that CD4(+ )T helper 2 (Th2) cell proliferation and overexpression of Th2 cytokines may play an important role in the development of Kimura disease. Chronic rejection of a renal allograft by the indirect allo recognition pathway is also induced by Th2 cytokines. We report a 12-year-old boy who had presented with nephrotic syndrome 10 years previously. He was found to have focal segmental glomerulosclerosis, which was attributed to vesicoureteral reflux, and he underwent renal transplantation at the age of 5 years. Allograft dysfunction secondary to chronic rejection was noted by 2 years post transplant, after which continuous ambulatory peritoneal dialysis was instituted. After discontinuation of immunosuppressive therapy, he progressively developed peripheral eosinophilia and eczema, followed by cervical lymphadenopathy and then epitrochlear lymphadenopathy. Kimura disease was diagnosed on lymph node biopsy. Our patient demonstrated that Kimura disease can occur after renal allograft failure secondary to chronic rejection. Both disorders involve the Th2-dominant immune response, according to previous observations.