Clinical feature: 

Definition: This disease is characterized by kidney stone fomation due to increased renal excretion of the amino acid cystein. The stones are made of cystine.

Pathogenesis: The filtered amino acid could not be reabsorbed adequately because of a defect in the transporter of dibasic amino acids.

Epidemiology: The Cystinurie is one of the most frequent hereditary diseases.The frequency is indicated in our population as 1:7000.

Diagnostics: 

Strategy: The Cystinuria can be mesured in quantitatively. Kidney stones should be investigated. If there something indicates for cystinuria a genetic test can be performed.

Literature: 

Schmidt C et al. (2003) Genetic variations of the SLC7A9 gene: allele distribution of 13 polymorphic sites in German cystinuria patients and controls.
de Sanctis L et al. (2001) Cystinuria phenotyping by oral lysine and arginine loading.
Rosenberg LE et al. (1966) Cystinuria: biochemical evidence for three genetically distinct diseases.