Percutaneous nephrolithotomy of kidney stones

Percutaneous nephrolithotomy is used for the surgical treatment of kidney stones. Most kidney stones in children are caused by infections. Boys are more common than girls, with the highest incidence between 2 and 3 years old. The most common pathogenic organisms are Proteus or E. coli that break down urea. The stones formed by Proteus repeatedly in the urine are soft and contain a large amount of biological matrix, often X-ray transparent stones. The stone composition contains magnesium ammonium phosphate (struvite) and small amounts of calcium phosphate (apatite), oxalate, carbonate, and urate. These components can attach freely or in a wide range to the pyelopenic system, and sometimes they can be complicated by pyelema, perirenal abscess, or progressive pyelonephritis. Fewer metabolic stones in children. Hypercalcemia can be idiopathic or caused by excessive vitamin D or hypophosphatemia, usually causing renal calcium deposits. Hyperparathyroidism is rare in children. The definition of hypercalciuria is that the 24h urine calcium is above 4mg / kg, and the urine calcium / creatinine ratio is> 0.25. Hypercalciuria also occurs in some children with stone infections, especially when they have excess milk. Phosphateuria can cause renal tubular acidosis, hypercalciuria and recurrent urinary stones. In addition to renal calcium, hyperoxaluria can also produce renal calcium and recurrent oxalate stones. It is more likely to occur if the urinary tract is obstructed. Uric acid stones often occur in children with leukemia, often due to calcium deposition, opaque on X-ray films, but low density. Xanthine and dihydroadenine stones are light-transmitting stones.