Update in Diagnosis and Management
Cystine stones are only seen in patients with cystinuria, a genetic disorder in which transporters in the proximal tubular which reabsorbed filtered amino acids are not functioning normally. Although urinary levels of other dibasic amino acids are also high, the patients develop cystine stones because cystine is not very soluble in urine.
The mainstay of treatment is forced diuresis by drinking copious amounts of fluids. Low sodium and protein intake can marginally reduce urinary cystine excretion, and cystine is somewhat more soluble in alkaline urine. D-penicillamine and thiola are 2 drugs which can complex cystine to increase its solubility. However, both have potential side effects so are reserved for patients that fail other more conservative measures.
Jump to section:
- Kidney Stones
- Why do Kidney Stones Form?
- Genetics and Environment
- Not All Stones are Created Equal: Stone Analysis is Very Helpful
- Laboratory Evaluation
- Supersaturation Index
- Components of the Urinary Supersaturation Profile
- Uses of Urinary Supersaturation
- Common Features Increase Urinary Supersaturation in Patients with Idiopathic Calcium Oxalate Nephrolithiasis
- "Conservative" Dietary Recommendations for Calcium Oxalate Stone Formers
- Causes of Hypercalciuria
- Genetic Hypercalciuria
- Genetic Hypercalciuria: Treatment
- What is Oxalate?
- Hyperoxaluria: What is the Relevant Concentration?
- Oxalate Balance on a Typical Western Diet
- Enteric Hyperoxaluria is Caused by Fat Malabsorption
- Control of Urinary Citrate: Largely Due to Systemic Acid Base Balance
- Treatments for Enteric Hyperoxaluria
- Low Urinary Citrate
- Hyperuricosuria is a Risk Factor for Calcium Oxalate Stones
- Uric Acid is Very Insoluble at Low pH
- Calcium Phosphate is Very Insoluble at High pH!
- Cystine Stones
- Struvite stones