Urine contains a large number of different chemicals. Under some circumstances, these chemicals may solidify into salt crystals. This is called crystalluria.
Crystals can be found in the urine of healthy individuals. They may be caused by minor issues like a slight excess of protein or vitamin C. Many types of urine crystals are relatively harmless.
In some cases, however, urine crystals can be indicators of a more serious underlying condition. Symptoms that would indicate a more serious condition could include:
- severe abdominal pain
- blood in the urine
Read on to learn more about the different types of crystals and how they’re treated.
There are a number of different types of urine crystals.
Uric acid crystals can be different types of shapes: barrel, plate-like, or diamond. They’re typically orange-brown or yellow in color. They can be found in normal urine when caused by a protein-rich diet, which increases uric acid in the urine. They can also be caused by kidney stones, gout, chemotherapy, or tumor lysis syndrome.
Symptoms of kidney stones include severe abdominal, flank, or groin pain; nausea; and blood in the urine. Symptoms of gout can include burning pain, stiffness, and swelling in a joint.
Treatment depends on the underlying condition, but staying hydrated is one of the best ways to treat the crystals themselves. Check out these water-rich foods that can help you stay hydrated.
Calcium oxalate crystals are shaped like dumbbells or envelopes. They’re colorless and can be found in healthy urine.
Calcium oxalate crystals are heavily associated with kidney stones, which can form when too much oxalate (found in foods like spinach) is in the system. Kidney stone symptoms include severe groin or abdominal pain, nausea, fever, and difficulty passing urine. These natural remedies can help you fight kidney stones at home.
In some cases, calcium oxalate crystals can be caused by the ingestion of ethylene glycol, which is toxic and is an essential ingredient in antifreeze formulations. Exposure to this compound can cause symptoms such as:
- throat and lung irritation
- central nervous system problems
- renal failure
Your doctor may recommend dietary changes to reduce oxalate in your diet and increase hydration. They’ll also likely recommend that you reduce salty foods.
Hippuric acid crystals are rare. They may be either yellow-brown or clear, and they often resemble needle-like prisms or plates. Hippuric acid crystals are often found clustered together.
While they are sometimes caused by an acidic urine pH, hippuric acid crystals can also occur in healthy urine.
Magnesium ammonium phosphate (struvite)
Magnesium ammonium phosphate crystals are often colorless, rectangular prisms. They can be found in healthy urine, but they typically coincide with a urinary tract infection (UTI). Other symptoms of UTIs include:
- cloudy urine
- frequent, intense urge to urinate
- lower back pain
If a UTI is causing these crystals, your doctor will prescribe you antibiotics to clear up the infection.
Calcium phosphate crystals are large, round discs with smooth surfaces. They’re often a light brown color. Crystals of calcium phosphate — which is a supplement you can take to get more calcium — are also frequently associated with kidney stones.
Bilirubin is made when the healthy destruction of red blood cells occurs. It’s passed through the liver.
Bilirubin crystals have a needle-like, granular appearance and are often very small and yellow in color. High levels of bilirubin or bilirubin crystals in your urine could indicate liver disease or poor liver function. Other symptoms may include nausea, pain, vomiting, jaundice, and fever.
Treatment depends on the underlying cause. Medications may be used to change the amount of protein that’s absorbed in the diet, especially in cases of cirrhosis.
Calcium phosphate crystals are colorless and may appear as star-like or needle-like, though they may also form plates. They may show up alone or in clusters. They often appear in alkaline urine, though they can be found in normal urine.
In rare cases, calcium phosphate crystals could by caused by hypoparathyroidism. Symptoms of this include tingling in the hands and muscle cramping.
Treatment may include drinking more water, getting more calcium, and taking vitamin D supplements.
These crystals are brown spheres with spiky thorns. They almost resemble small bugs. They’re often found in alkaline urine, but they can also be seen in normal urine.
Sometimes, ammonium biurate crystals only appear because the urine sample is old or has been poorly preserved. Because of this, recollecting the urine sample may be advised if these crystals appear.
Cholesterol crystals are often clear and shaped like long rectangles, with a notch cut out at the corner. They’re most likely to appear after the urine sample has been refrigerated.
Cholesterol crystals can be found in both neutral and acid urine. They may be caused by renal tubular disease, which can lead to renal failure if left untreated.
Treatment may involve alkali therapy to help treat chronic metabolic conditions, like renal tubular disease.
Cystine is an amino acid, and it can cause urine crystals and kidney stones. Kidney stones caused by cystine acid are typically larger than most other kidney stones. It’s a rare condition, and often genetic.
The condition that causes cystine to bind together and form the crystals is called cystinuria. The crystals, when found in urine, are often shaped like hexagons and may be colorless. Symptoms may include blood in the urine, nausea and vomiting, and pain in the groin or back.
Your doctor may prescribe chelating medications which help to dissolve the crystals.
These crystals are yellow-brown disks with concentric rings like a tree trunk. Leucine crystals are typically not found in healthy urine. They’re found in acidic urine. They’re typically a symptom of severe liver disease. Other symptoms may include abdominal swelling, vomiting, nausea, disorientation, and malaise.
Treatment involves improving liver function and health immediately. This will include medications to reduce the risk of bleeding and reduce swelling caused by excess fluid.
Tyrosine crystals are colorless and needle-like. They’re often found in acidic urine, and they may be caused by metabolic disorders like liver disease or tyrosinemia. Symptoms of tyrosinemia include difficulty gaining weight, fever, diarrhea, bloody stools, and vomiting.
Treatment includes exercising, eating a healthy diet, and taking medications that may be able to treat high blood pressure, high cholesterol, and diabetes.
Indinavir is a medication used to treat HIV. It can cause the formation of crystals in the urine. Indinavir crystals may resemble starbursts, rectangular plates, or fans. Other symptoms of indinavir crystals may include back or flank pain.
If your doctor suspects that you have urine crystals, they’ll likely first order a urinalysis. In some cases, your doctor may run a urinalysis as part of your wellness visit or annual checkup, even if you don’t have other complaints.
For the urinalysis test, you’ll be asked to provide a urine sample. The lab technician reviewing the sample will first observe it for any color or cloudiness that may indicate an infection. Bilirubin can turn urine a dark tea color, for example. Blood may be evident to the naked eye. They’ll then use a dipstick to test for components within the urine. The technician will finally examine the sample under a microscope, where they can actually see the crystals if any have formed.
Depending on what your doctor finds, they may order additional tests. If they find bilirubin in your urine, for example, they may order blood work or an ultrasound to evaluate your liver health. If urine crystals indicate high cholesterol, they’ll order a blood test to evaluate your current cholesterol levels.
Urine crystals that aren’t caused by underlying conditions like liver disease or genetic conditions can often be prevented. In some cases, even crystalluria triggered by genetic causes can be reduced with lifestyle or diet changes.
The most effective way to prevent urine crystals is to drink more water and stay hydrated. This helps dilute the chemical concentrations in the urine, preventing crystals from forming.
You can also make certain changes in your diet. Your doctor can help you determine what changes to make based on the type of crystals that you have. They may recommend cutting back on protein, for example, or reducing foods high in oxalate (as is the case for calcium oxalate crystals). Avoiding salty foods can also help prevent a number of different urine crystals, so eliminating processed foods can be beneficial.
In many instances, urine crystals are highly treatable with lifestyle and diet changes. In some cases, medication may be required to treat underlying conditions.
If you experience any changes in your urine, make an appointment to see your doctor. Knowing exactly what type of crystals are forming will help you and your doctor to understand what’s causing the issue and how to treat it.