Kanchana TangnararatchakitWatcharin AriyaprakaiWiwat Tapaneya-OlarnVorasuk ShotelersukThanom PetchthongMahidol UniversityChulalongkorn University2018-07-242018-07-242002-11-01Journal of the Medical Association of Thailand. Vol.85, No.SUPPL. 4 (2002)012522082-s2.0-0036881430https://repository.li.mahidol.ac.th/handle/123456789/20325This paper presents the case report of a 4-year and 6-month old girl with cystinuria. She clinically presented with recurrent radiopaque renal stones since the age of 3 years. She received 2 subsequent operations of pyelolithotomy combined with ureterolithotomy at the age of 3 years 6 months, and pyelolithotomy alone at the age of 5 years. She was initially diagnosed as having cystinuria by the presence of hexagonal plate crystals in her acidified urine and positive for the urinary cyanide-nitroprusside test. The diagnosis was confirmed by urinary amino acid analysis using quantitative ion-exchange chromatography which revealed increased amounts of cystine and dibasic amino acids of lysine and omithine. In spite of maintaining a high fluid intake and alkalinizing urine by giving potassium citrate after the first operation, recurrent renal stones were found. Therefore, after the second operation, D-penicillamine was additionally introduced. During the 18-month follow-up, although there were recurrent renal stones, the rate of stone formation was slower. To the authors' knowledge, this is the first case report in Thailand.Mahidol UniversityMedicineArticleSCOPUS