Question

Which stone secretes amino acids?

Answer 1

Cystine stones are a specific type of kidney stone that form as a result of a genetic condition called cystinuria. This condition leads to the excessive excretion of the amino acid cystine in the urine. Cystine is a sulfur-containing amino acid that is normally found in the body’s proteins. However, in individuals with cystinuria, the kidneys fail to reabsorb cystine efficiently, leading to an increased concentration of cystine in the urine.

As the concentration of cystine increases, it can exceed its solubility limit, causing cystine to form crystals in the kidneys, which can eventually grow into stones. These cystine stones are typically hard, yellowish stones that can cause severe pain and blockage in the urinary tract.

Key points about Cystine Stones:
- Cystine stones are primarily composed of cystine, an amino acid that forms crystals in the urine.
- The condition that leads to cystine stone formation is called cystinuria, which is inherited genetically.
- Cystinuria causes the kidneys to excrete excess cystine into the urine, where it can crystallize and form stones.
- These stones are typically formed when the cystine concentration in urine exceeds its solubility limit.
- Cystine stones are more likely to occur in individuals with a family history of cystinuria.

Treatment for Cystine Stones:
Treatment for cystine stones typically involves increasing fluid intake to dilute the urine, which helps prevent cystine from crystallizing. Medications such as potassium citrate may also be prescribed to alkalinize the urine and increase the solubility of cystine. In some cases, surgical intervention may be required to remove large stones that cause blockage or pain.