Computed tomography or ultrasound may be used instead for imaging.Urine odor in cystinuria has a smell of rotten eggs due to the increase in cystine. Genetics
Cystinuria is an autosomal recessive disease, which means that the defective gene responsible for the disease is located on an autosome, and two copies of the defective gene (one inherited from each parent) are required in order to be born with the disease. The parents of an individual with an autosomal recessive disease both carry one copy of the defective gene, but usually do not experience any signs or symptoms of the disease. Although signs and symptoms are rare, there are some directly and indirectly associated with cystinuria. These sign and symptoms consist of 1) hematuria- blood in the urine, 2) flank pain – pain in the side due to kidney pain, 3) renal colic – intense, cramping pain due to stones in the urinary tract, 4) obstructive uropathy- urinary tract disease due to obstruction, and 5) urinary tract infections. Cause
Cystinuria is caused by mutations in the SLC3A1 and SLC7A9 genes. These defects prevent proper reabsorption of basic, or positively charged, amino acids: cystine,  lysine, ornithine, arginine. Under normal circumstances, this protein allows certain amino acids, including cystine, to be reabsorbed into the blood from the filtered fluid that will become urine. Mutations in either of these genes disrupt the ability of this transporter protein to reabsorb these amino acids, allowing them to become concentrated in the urine.
Crossed dystopia (syn.unilateral fusion cross fused renal ectopia) is a rare form of renal ectopia where both kidneys are on the same side of the spine. In many cases, the two kidneys are fused together, yet retain their own vessels and ureters. The ureter of the lower kidney crosses the midline to enter the bladder on the contralateral side. Both renal pelves can lie one above each other medial to the renal parenchyma (unilateral long kidney) or the pelvis of the crossed kidney faces laterally (unilateral "S" shaped kidney). Urogram is diagnostic. The anomaly can be diagnosed through ultrasound or urography, but surgical intervention is only necessary if there are other complications, such as tumors or pyelonephritis. == References ==