Cystinuria is a disease that is inherited and causes stones. These stones are made up of cysteine. This forms in the kidneys, bladder, and ureters. To develop Cystinuria, the patient must acquired genetic defect from both the parents. The defect in the gene causes cystine to get accumulated inside the kidneys. The main functions of the kidneys are as follows:
- Reabsorbing essential minerals and proteins back into the body.
- Filtering the blood to remove toxic waste.
- Producing urine to excrete waste from the body.
The amino acid cysteine forms stones in the kidneys instead of flowing back to the bloodstream. Many treatments can help in the prevention of these diseases. People often wonder what cystine is; in that case, they should know that it can be serious if not treated on time. In this article, we shall study Cystinuria, its causes, and treatment methods that can help the patients prevent this disease.
Symptoms Of Cystinuria
Cystinuria is a lifelong condition that occurs first in young adults. The cystine crystals can recur many times. Some of the main symptoms of Cystinuria include:
- Blood in urine
- Abnormal pain inside and the back
- Pain near pelvis and abdomen
What Causes Cystinuria
Defects in the genes cause Cystinuria. These defects are also known as mutations. In the case of Cystinuria, the genes give instructions to the body to make transporter proteins found in the kidneys, and this particular protein controls over reabsorption of amino acids. Cystine crystals in urine give tremendous pain to the patients.
Amino acids are formed when the proteins are broken down. They are used for performing a variety of bodily functions. They are important to the body and are not considered waste. So when these amino acids enter the kidneys, they are reabsorbed in the bloodstream. People suffering from Cystinuria have mutations that interfere with the ability of the transporter proteins to reabsorb amino acids. Patients who have cysteine in urine should take special care of themselves.
One of the amino acids, cystine, is not very soluble in urine. If these are not reabsorbed, they can accumulate inside the kidney and form crystals or cystine stones. These hard stones get stuck in the kidneys, bladder, and ureters. It can cause unbearable pain.
Risks For Cystinuria
A person can get Cystinuria only when parents have specific genes causing these diseases, and inheritance also causes Cystinuria. This particular type of disease occurs in about 1 in every 10,000 people worldwide. Cystine stones can be very dangerous for health if they are not treated correctly.
Diagnosis Of Cystinuria
A person goes for diagnosis of Cystinuria only when they experience any kidney stones episode. They undergo an examination which is made to check whether the stones are made out of cystine or not. Genetic testing is rarely done. There are several methods through which Cystinuria can be diagnosed. Additional Cystinuria diagnostic testing includes the following:
1.24 Hour Urine Collection
The patient is asked to collect their urine in a container over an entire day. The urine is then sent to the laboratory for analysis. This analysis determines the making up of the stones and other factors.
2. Abdominal CT Scan
An abdominal CT scan is a type of cystinuria diagnostic testing that uses x-rays to create images of the structures found inside the abdomen. They look for stones that are present in the kidney.
Urinalysis is the urine examination in the laboratory, which involves looking at the color and physical description of the urine. The entire urinalysis procedure is done by viewing the urine under a microscope and conducting a chemical examination to detect certain substances such as cystine.
Complications Of Cystinuria
Cystinuria can be extremely painful and can lead to serious complications if it is not treated appropriately. Some severe complications of different Cystinuria types include the following:
- Kidney or bladder damage from a stone.
- Urinary tract Infections
- Kidney Infections
- Ureteral obstruction ( it is a blockage in the ureter, the tube which drains urine from the kidneys into the bladder.
Medication And Surgery Of Cystinuria
Every disease, whether acute or chronic, requires proper medication. In case of Cystinuria, medications commonly known as chelating agents help in dissolving cystine crystals.
In the case of Cystinuria, D-penicillamine and alpha-mercapto propionylglycine are the most common medicines. D-penicillamine is the most effective medicine for the treatment of such a disease. The doctor can also prescribe pain medication for controlling the pain when the stone passes through the bladder or whenever the patient experiences any Cystinuria symptoms.
Under any condition, if the doctor sees that the stones are very large and painful, they might need to remove them surgically. Surgical procedures like extracorporeal shock wave lithotripsy, percutaneous nephrolithotomy, ureteroscopy and leaser lithotripsy are commonly used for curing Cystinuria.
The Bottom Line
Cystinuria is a disease that cannot be prevented if both parents carry genetic defects. The stones of Cystinuria are found in young adults under the age of 40. However, drinking adequate amounts of water and reducing salt intake can help prevent the formation of stones.
Dr. Saurabh Bhargava | Senior Consultant – Robotic Surgery, Urology | Mazumdar Shaw Medical Center, Bommasandra, Bangalore