Cystinuria affects 1 in 7,000 people in the United States, making it one of the most common genetic kidney diseases [1]. It often starts in childhood and can lead to kidney complications [1]. Here’s what to know.
What Is Cystinuria?
Cystinuria is a genetic or inherited condition that causes problems reabsorbing cystine in the kidneys and overexcretion of an amino acid called cystine into the urine [1]. Cystine levels become abnormally high, leading to undissolved cystine crystals in the urine and cystine kidney stones [2].
Changes in the SLC3A1 and SLC7A9 genes are responsible for cystinuria, which is an autosomal recessive disease [2]. You must have two copies of these gene changes to develop the condition, one from each parent [2]. The condition typically starts in childhood or young adulthood, between; ages 10 and 30 [2].
Symptoms of Cystinuria
Cystinuria only causes symptoms if you have a stone. These symptoms are much like those of other stones, including [3]:
- Sharp pain in your lower back, side, or belly
- Blood in your urine
- Nausea
- Vomiting
- Pain in your groin or pelvis
You may have jagged stones and urinary gravel or yellow-brown hexagon crystals [2]
Diagnosis of Cystinuria
The most common diagnosis tool is urine tests — such as urinalysis using urine test strips — and a microscope exam of urine and stones. Your doctor might also do a 24-hour urine test to check cystine levels, a kidney ultrasound to confirm stones, and genetic testing [1].
Treatment of Cystinuria
Treatment starts with lifestyle changes that help prevent stones from forming. If stones form despite these habits, you may need medication. Self-care habits include [3]:
- Drinking lots of water
- Eating more fruits and vegetables and less meat
- Eating a low-salt diet
Medications can help make your urine less acidic or stop stones from forming [1]. These include [1]:
- Sodium bicarbonate
- Alpha-lipoic acid
- Acetazolamide
- Thiol-based drugs
- Penicillamine
- ACE inhibitors
In some cases, you may need shock wave therapy to dissolve stones or surgery to remove them [1].
Complications of Cystinuria
Cystinuria leads to frequent stones, which, unfortunately, can cause complications. The average patient makes one stone every one to two years and has one surgery every three years [1]. By middle age, the average patient has had seven surgeries [1].
Cystinuria has a high risk of causing kidney damage or failure, as high as 70% [1] .Between 20% and 40% of patients also have other abnormal urine chemical levels that can cause different kidney stones [1]. Frequent stones and blockages can also lead to a higher risk of urinary tract infections (UTIs), kidney infections, and kidney damage [4].
Managing Cystinuria With UTI Home Tests
You can often prevent stones from forming by tracking your urine pH and changing your diet and fluid intake [1]. The goal is to aim for a urinary pH of 7.5, and if your levels are too low, you can drink mineral water or citrus juices to raise your pH [1].
You can also use urine pH test strips to monitor urinary pH. Additionally, UTI home tests or UTI test strips can be used to watch for signs of UTIs, blood, and protein that may mean you have a blockage or infection [1].
Track Your Urinary Health With Diagnox
Cystinuria is a long-term condition that requires daily management [1]. Diagnox UTI test strips or multi-parameter tests help you monitor your urine to make smart decisions about your health and habits.
