Cystinuria is an inherited defect of the renal tubules, caused by a decrease in renal tubular reabsorption of cystine and an increase in urinary levels, often with cystine stone formation in the urinary tract. Cystinuria is autosomal recessive and urinary cystine secretion can also be increased in heterozygotes, but stones are rarely formed. Reabsorption of the dibasic amino acids (lysine, arginine, ornithine) is also affected, but does not cause symptoms because they share a transport channel with cystine, in addition to a separate transport system. They are also more soluble in urine than cystine and thus do not cause crystallization and stone formation. Their absorption (including cystine) in the small intestine is also reduced. Pediatric polycystic tubular dysfunction syndrome Polycystic tubular dysfunction syndrome, Fanconi II syndrome, also known as de Toni-Debre-Fanconi syndrome, renal diabetic dwarf combined with hypophosphatemic rickets, osteomalacia-renal diabetic-amino aciduria-hyperphosphaturia syndrome, rickets nephrotic osteomalacia glycine phosphatiduria diabetic syndrome , bone-nephrotic syndrome, familial juvenile nephrotic syndrome, Lignac syndrome, Lignac-Fanconi syndrome, Fanconi-Toni-Deber syndrome, etc. Bladder stones Bladder stones are stones that form in the bladder and it can be divided into primary and secondary bladder stones. The former refers to stones formed in the bladder, mostly due to malnutrition, mostly in children, with the continuous development of China’s economy, children’s bladder stones are now on the decline; the latter refers to bladder stones formed from the upper urinary tract or secondary to lower urinary tract obstruction, infection, foreign body in the bladder or neurogenic bladder, etc. In economically developed areas, bladder stones mainly occur in older men, and most suffer from prostatic hyperplasia or urethral stricture, while in poor areas, they are more common in children and less common in women.