Crystals in Urine

Urine is one of the body’s ways of excreting waste products. It contains many chemicals and some of them are in the form of solid particles, particularly crystals.

Some crystals are normally present in the urine while others could indicate an abnormality. Presence of crystals in the urine is called crystalluria. ^{(1, 2)}

Crystals in urine : Symptoms

Presence of crystals in urine is difficult to identify using bare eyes. You should check the color of urine. If the color changes than the usual, then it could indicate crystals in urine. To correctly identify the presence of crystals, a urine test or urinalysis should be done. ^{(1, 2)}

 

Image 1 : A chart with images of crystals normally found in the urine as well as those abnormally found in urine.
Picture Source : www.microbiologyinfo.com

Picture 2 : A chart of crystals found in urine with acidic pH and urine with alkaline pH.
Photo Source : www.medical-labs.net

What causes crystals in urine?

Crystals in the urine are formed when the urine’s pH level become alkaline or more acidic. Various factors could lead to the development of crystals in urine. They include the following:

• Dehydration – If you do not have enough water in your body, the urine content will not be thoroughly diluted. It could result to the formation of crystals and eventually, kidney stones.
• Change in urine pH – Urine is normally acidic. However, if it gets too acidic there is a possibility of calcium oxalate crystal formation. If it gets too alkaline, calcium phosphate crystals will most likely develop.
• Diet – High in protein and oxalate diet could lead to formation of crystals in the urine. It could possibly lead to kidney stones too.
• Urinary Tract Infection (UTI) – Frequent urinary tract infection could alter the pH level of urine. Over time, it could lead to crystal formation in the urine. ^{(2, 3,4)}

Types of Urine Crystals

Crystals that are normal in urine

Uric acid crystals urine

Uric acid is the by-product of protein digestion. It looks like a diamond or barrel and its colors are usually yellow to orange brown. Uric acid crystals are normally present in urine, but too many uric acid crystals could indicate gout, kidney stones, uric acid nephropathy, and urate nephrolithiasis.

People receiving chemotherapy drugs also have the tendency to have uric acid crystals in the urine. Uric acid crystals forms in acidic urine.

Calcium oxalate crystals in urine

What does it mean to have calcium oxalate crystals in urine? It could indicate that the patient is suffering from nephrolithiasis and acute renal failure. Although, calcium oxalate crystals is present in the urine of people with high dietary oxalate ingestion and too much intake of vitamin C.

It is found in acidic urine. Calcium oxalate crystals are available in two forms: monohydrate and dihydrate. Monohydrate form looks like a picket fence while the dihydrate form looks like an envelope.

Triple phosphate crystals in urine

They are also called struvite crystals. They are colorless and look like rectangular prisms. They are usually found in urine with neutral to alkaline pH.

It is just normal to have triple phosphate crystals in the urine, but too many of them could indicate that you are suffering from urinary tract infection. Triple phosphate crystals are made up of magnesium ammonium phosphate.

Hippuric acid Crystals

They can be found on neutral, slightly alkaline, and acidic urine. They look like prisms, needle-like shape, or plates.

Calcium carbonate crystals

They look like large spheroids with radial striations. Calcium carbonate in smaller size has a round to ovoid shape. The color is usually colorless to yellow brown. There will be a significant change in urine color. The urine is brownish tinge, especially if the calcium carbonate crystals go out of control.

Calcium phosphate crystals in urine

They are colorless crystals, which look like rosettes, prisms, or blunt ended needles. They are commonly found in urine with neutral to alkaline pH.

Ammonium biurate crystals

They are commonly found in alkaline urine and appear brown or yellow brown spherical bodies. They look like throny apples because of their irregular protrusions.

Amorphous phosphate crystals

They can be a mixture of urates, xanthine, or phosphates. They are very small and can only be visualized at high magnification. They are commonly found in acidic urine and yellow to brownish in color. A small amount of amorphous phosphate crystals can be mistaken with bacterial cocci. To distinguish the two, a gram-staining should be performed. ^{(3, 4, 5, 6,7)}

Crystals not commonly found in urine

Bilirubin crystals in urine

The crystals are formed from conjugated bilirubin. They are yellow in color and look like needle. They are very tiny and can only be viewed at high magnification. They are commonly found in the urine of canine, but of no clinical significance. They can also be seen in patients with hepatic disorders.

Cholesterol crystals

They are usually found in acidic urine and is associated with nephrotic syndrome. Cholesterol crystals are typically colorless and look like rectangular plates with a notch in the corners.

Leucine crystals

This is usually found in the urine of people with impairment of amino acid metabolism, especially in people with liver disease. The leucine crystals are yellowish to brownish sphere. They have concentric circles with striations.

Tyrosine crystals

They are commonly found in urine with neutral to acidic pH. They look like colorless to yellow fined needles. They are commonly found in the urine of people with liver-related disease.

Cystine crystals in urine

They are present in acidic urine. Those people with cystine crystals in the urine could be suffering from proximal tubular defect in reabsorption of amino acid. Cystine crystals look like colorless plate, flat, and hexagonal-like shape.

Sulfanomide Crystals

Presence of this type of crystal does not indicate any pathological condition. However, it could be linked with drug administration. They are usually brown in color and look like flat needles. ^(6,8,9)

For substance-related crystals in the urine such as methamphetamine, a crystal meth urine test is ordered. This is to identify whether or not the person used methamphetamine, which is an illegal drug.

How long does crystal methamphetamine stay in your urine?

Well, it primarily depends on the ingestion route. Smoking crystal meth could take three to five days before it leaves the whole body. Snorting would take around four days to be completely excreted from the body.

On the other hand, if meth is taken intravenously, it would take around 72 hours before it will be cleared in your urine. ⁽¹⁰⁾

Also see : Cloudy Urine

References:

1. www.livestrong.com
2. diseasespictures.com
3. www.microbiologyinfo.com
4. byebyedoctor.com
5. laboratoryinfo.com
6. www.kidney.org
7. www.tandurust.com
8. https://academic.oup.com
9. www.webmd.com
10. www.belmarrahealth.com