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Cystine Calculi
Aka: Cystine Calculi, Cystine Stone, Cystine Nephrolithiasis, Cystinuria
- See Also
- Nephrolithiasis
- Pathophysiology
- Disorder of dibasic amino acid transport
- Results in decreased renal cystine resorption
- Cystine dissolves poorly at normal Urine pH
- Calculi form at cystine concentration >250 mg/day
- Autosomal recessive inheritance
- Only homozygote patients form Cystine Stones
- Types
- Pure Cystine Stones
- Mixed cystine and calcium oxalate
- Management
- General
- Diuresis: reduce cystine <300 mg/L
- Alkalinize urine (especially if Urine pH is low, acidic)
- Maintain Urine pH >5.5 (6.5 - 7.0 preferred)
- Potassium Citrate 10-20 mEq orally three times daily with meals
- Calcium Citrate 500 mg, two tablets daily with meals
- Protocol
- Tiopronin (Thiola) and
- Increase fluid intake to maximize urine output
- Other management
- Penecillamine
- Chemolysis (Tham-E, Acetylcysteine)
- Extracorporeal Shock Wave Lithotripsy (ESWL)
- References
- Mobley (Feb 1999) Hospital Medicine, p. 21-38
- Goldfarb (1999) Am Fam Physician 60(8): 2269-76
- Houshiar (1996) Postgrad Med 100(4): 131-8
- Frassetto (2011) Am Fam Physician 84(11): 1234-42
- Pietrow (2006) Am fam Physician 74(1): 86-94
- Preminger (2007) J Urol 178(6): 2418-34
- Portis (2001) Am Fam Physician 63(7):1329-38
- Segura (1997) J Urol 158:1915-21
- Teichman (2004) N Engl J Med 350:684-93
- Trivedi (1996) Postgrad Med, 100(6): 63-78