Nephrocalcinosis among children at king hussein medical center: Causes and outcome.

Nephrocalcinosis (NC) is defined as deposition of calcium crystals in the renal parenchyma and tubules. This is a retrospective review of all the data of 63 children presented to Pediatric Nephrology Clinic at King Hussein Medical Center (KHMC) over a 15-year period with bilateral NC. We determine their causes, clinical presentation and evaluate their growth and renal function during their follow-up. Thirty-five (55.5%) cases were males and 28 (44.5%) were females. The median (range) age at presentation was four (2-192) months. The most common leading cause to NC was hereditary tubulopathy in 48% followed by hyperoxaluria in 35%. The cause of NC remained unknown in 3% and Vitamin D excess accounts for 5% of the cases. The most presenting symptom was a failure to thrive (68%) and the second most common symptom was abdominal pain and recurrent urinary tract infection was found in 40%, polyuria and polydipsia were found in 32% of cases, and 16% of cases were diagnosed incidentally. At a median follow-up of 38 (14-200) months, estimated glomerular filtration rate had decreased from 84.0 (42-110) mL/min per 1.73 m2 body surface area to 68.2 (10-110) mL/min/1.73 m2 body surface (P = 0.001). This study illustrated the need for a national registry of rare renal diseases to help understand the causes of these conditions in our populations and provide support to affected patients and their families.

The clinical pattern of primary hyperoxaluria in pediatric patient at Queen Rania Abdulla Children Hospital.

INTRODUCTION: Hyperoxaluria is a metabolic disorder that can lead to end stage renal disease (ESRD). It can be either inherited or acquired. Primary hyperoxaluria (PHO) is more common and characterized by an excessive production of oxalate leading to recurrent urolithiasis and progressive nephrocalcinosis. Due to the high rate of consanguineous marriage in Jordan this disease is commonly diagnosed in pediatric nephrology clinics. We aimed to demonstrate the clinical pattern and progression to ESRD in pediatric patients with hyperoxaluria at Queen Rania Abdulla Children Hospital. METHODS: Medical records of all patients followed up in the pediatric nephrology clinic with the diagnosis of PHO during the period between September 2007 and March 2013 were reviewed. RESULTS: There were 70 patients with the diagnosis of PHO, 52.9% were males. The median age at presentation was 3 years ± 3 months with the youngest child being two months old. Diagnosis was made in the first year of life in 15.7% of patients. The most common presenting symptom was hematuria, while 14% of patients were asymptomatic and detected by family screening after the diagnosis of an index case. At the time of initial presentation, 15.7% of patients had ESRD and 25% had impaired renal function. Kidney stones were found in 57% of cases and nephrocalcinosis was found in 37%. CONCLUSION: High index of suspicion is needed to diagnose PHO in children presenting with kidney stone or unexplained hematuria. Twenty-four hour urine collection for oxalate are required to make the proper diagnosis. Family screening, when appropriate, is indicated for early detection of PHO.

Hypercalcemia, hypercalciuria and nephrocalcinosis in a breast-fed term newborn: a rare presentation.

Although hypercalcemia and hypercalciuria are known to occur in breast-fed pre-term infants, to the best of our knowledge, it has never been reported in a term baby previously. We report a term male baby who was followed-up during pregnancy for having bright kidneys, but a follow-up renal ultrasound (US) after birth had revealed normal scan. Laboratory investigations revealed normal serum calcium (Ca), phosphorous (PO4) and alkaline phosphatase (ALP). The baby was being fed by breast milk. Follow-up US two months later showed early nephrocalcinosis along with hypercalcemia and hypercalciuria; by the age of three months, nephrocalcinosis was more extensive and the serum Ca level was more than 12 mg/L with hypercalciuria. Parathyroid hormone (PTH), phosphorous (PO4), ALP and thyroid function tests were all normal. Antenatal history revealed a hypothyroid mother who was maintained on L-thyroxin, calcium and vitamin D supplement during pregnancy. Her blood tests showed normal serum Ca, low PO4 and elevated PTH. The baby was diagnosed to have hypercalciuria and hypercalcemia secondary to maternal hypophosphatemia (maternal vitamin D deficiency). Breast feeding was stopped and the baby was started on formula, whereby he showed remarkable improvement both for his blood chemistry as well as his hypercalciuria.