SLC3A1 and cystinuria: In our cystinuria patient, the BUN (mmol/L), creatinine (Cre; μmol/L), and UA (μmol/L) levels were all higher than the average values found in other studies (Table 2), we suspect that this may be related to the variant type of SLC3A1 gene in the patient, as frameshift variants lead to more severe phenotypes than missense ones; after traditional treatments, including extracorporeal shock wave lithotripsy, alkalize urine and Oral medication treatment, these serum values normalized.