Metabolic evaluation of children with recurrent nephrolithiasis

This study was conducted to define the underlying metabolic causes of recurrent renal stones in children at Alexandria, Egypt Out of 52 children with renal stones referred to Alexandria University Hospitals during the one year period of the study; 20 were recurrent [38.5%]. Their age ranged between one and 14 years. Mean age of onset was 3.5 +/- 3 years. Recurrence rate was one to three episodes over a mean period of 2.5 +/- 2 years. Before enrolment in the study, cases were subjected to one or more settings of stone surgery and/or ESWL. Thorough clinical, imaging and metabolic evaluation was done to all cases. Chemical analysis and infrared spectroscopy of all available stones were done. The results of the study revealed that stone recurrence was due to metabolic errors in 80% of the cases while the remaining 20% were idiopathic with no evidence of underlying metabolic diseases. Hypercalciuria was detected in 40% of cases. It was associated with distal renal tubular acidosis [RTA-l] in 62.5% and due to idiopathic renal leak [IH] in 37.5%. Cystinuria was present in 20% of cases, hyperuricosuria due to GSD-I in 10% and primary hyperoxaluria in another 10%. Hypocitraturia was found in 55% of cases. Hydronephrosis and recurrent UTIs were detected in 40% and 55% of cases respectively. All children with recurrent renal stones should undergo thorough metabolic evaluation to detect underlying etiology. Different etiological factors may coexist in the same patient; but underlying metabolic defects are the commonest in children with recurrent nephrolithiasis; [80%] in the current work. Early diagnosis and treatment of such metabolic errors will prevent or decrease the morbidity caused by recurrence, and will save these children from hazards of repeated stone surgery or ESWL

Renal ultrasonography in neonates

Ultrasound [US] is a safe and accurate imaging method in the evaluation of urinary tract and its anomalies in neonates. It is helpful in establishing correct diagnosis in the majority of cases and facilitates precise measurement of kidney length. We conducted this work to study the prevalence and types of renal anomalies in Egyptian neonates and to identify their normal renal length. Our study was conducted on 500 Egyptian neonates, at Alexandria University Maternity and Children's Hospitals. Ultrasonographic examination and measurement of both kidneys were done in all neonates. Abnormal renal ultrasonographic findings were found in 15 neonates, with a prevalence of 3%. The abnormalities encountered were severe bilateral hydronephrosis in 8 cases [1.6%], moderate bilateral hydronephrosis in 3 cases [0.6%]. Horseshoe kidney, bilateral hyperechoic renal medulla, polycystic kidney disease [ARPKD], and unilateral renal tumor were detected in equal frequencies of 0.2% each. Further evaluation of the cases with severe hydronephrosis revealed: posterior urethral valve [PUV] in 5 cases, bilateral primary vesicouretral reflux [VUR] in 2 cases, bilateral pelviureteric junction obstruction [PUJO] in one case. Cases with moderate hydronephrosis resolved on follow-up. Sonographic renal appearance in normal neonates was different from that seen in older children. They showed a pattern of increased corticomedullary differentiation with markedly sonolucent medullary pyramids. The mean renal length in normal newborns was 4.7 +/- 0.7cm. There was a positive correlation between renal length and each of body length and weight than with age and head circumference. The high prevalence of renal anomalies in Egyptian neonates justifies early postnatal renal US examination of all neonates; especially those who had abnormal antenatal ultrasonographic findings. Early diagnosis of such anomalies will lead to proper early management and prevention of chronic renal failure