Urinary lithiasis is characterized by the presence of calculi or stones inside the kidneys or urinary tract (ureters, bladder). Kidney stones are composed of substances normally found in urine, but, for various reasons, they have aggregated to form solid fragments whose sizes can vary from a few millimeters to several centimeters.
What are they?
"Infectious lithiasis" is a term used to refer to stones associated with chronic urinary tract infection. The most common infectious lithiasis types are magnesium ammonium phosphate (struvite) and carboapatite. The most frequently associated bacteria are urease-producing bacteria.
These stones can form for two reasons: first, due to the presence of pathogenic bacteria which, through their urease activity, change environmental conditions and promote the crystallization of substances present in the urine. The second possible pathway for formation is from an existing stone that becomes infected.
Struvite stones usually grow rapidly. Within a few months, they can branch out and spread throughout the kidney cavities, forming a staghorn calculus.1
How are they treated?
Infectious lithiasis is characterized by three elements during diagnosis:
- The presence of urease-positive bacteria in the urine
- A urinary pH greater than 6.8 (alkaline pH)
- The presence of struvite crystals in the urine
Treatment requires complete removal of the stone, generally surgically, to avoid leaving fragments that could form another stone, eradication of the urinary infection through short- or long-term antibiotic treatment, and correction of risk factors (acidifying urinary pH with L-methionine, balancing the diet, recurrent urinary infections, etc.).2
How to avoid or prevent them?
1. Drink enough fluids
As we have mentioned before, do not forget that the most important thing to prevent stones is to drink large amounts of fluid daily (preferably water) to dilute substances that can crystallize and form new stones. We will know it's enough when the color of our urine is almost transparent.
2. Maintain a balanced diet3,4
- Dietary sodium restriction is important as it is associated with a reduction in urinary calcium excretion. To reduce sodium, it is necessary to follow a diet that reduces foods containing a lot of salt, such as canned foods, packaged foods, fast foods, condiments, dressings, and cured meats and cold cuts.
- Having too little calcium in your diet can increase oxalate levels and cause kidney stones. Make sure you get an appropriate amount of calcium for your age (between 1000 and 1200 milligrams daily). Ideally, get calcium from milk or other dairy products, along with 800 to 1,000 international units (IU) of vitamin D to help your body absorb calcium.
- Eat plenty of fruits and vegetables. It is recommended to eat at least 5 to 9 servings of fruits and vegetables a day for everyone. Eating fruits and vegetables provides potassium, fiber, magnesium, antioxidants, phytate, and citrate. These elements are known to help prevent stones from forming.
- If your doctor thinks your diet is increasing your risk of stones, they will tell you to eat less meat. This includes fish, seafood, poultry, pork, lamb, and game meat. You may be asked to eat animal protein only once a day or less, and to eat smaller portions.
3. Keep urinary pH in the appropriate range and use aids to inhibit crystallization
Remember the importance of maintaining your urinary pH within appropriate ranges (5.5-6.2) and aiding crystal inhibition thanks to products recommended by urologists and formulated with phytate and L-methionine ingredients.
