Urine contains dissolved substances (solutes), or waste products. These solutes can solidify forming crystals in the urine if the urine pH becomes increasingly acidic or basic and the concentration of dissolved substances increases.

According to Lab Tests Online, crystals are identified by their shape, color, and by the urine pH. Physicians consider crystals “normal” if they come from solutes usually found in urine.

If the crystals come from solutes that are not normally found in urine, then physicians consider them “abnormal.” Abnormal crystals may indicate an abnormal metabolic process.

Cystine crystals

Cystine crystals appear as flat hexagons in urine. The opaque cystine stones appear on x-rays; they occur in patients who have a genetic disorder in kidney and intestinal transport of amino acids, including cystine. Since cystine is insoluble, it accumulates in the urine forming stones.

Treatment includes drinking fluids to increase the urine pH (alkalinization) and administration of drugs to make cystine more soluble.

Oxalate Crystals

Oxalate crystals appear envelope-shaped in urine. Low-calcium diets can increase the absorption of oxalate due to less calcium binding in the intestine. So, people on low-calcium diets present a risk for developing oxalate crystals.

Treatment includes eating a diet low in oxalate. Note: spinach, nuts and chocolate are high in oxalate.

Triple Phosphate crystals

Triple phosphate crystals are shaped like a coffin lid, and consist of magnesium, ammonium and phosphate. They result from alkaline urine and with bacteria that causes urinary tract Infections.

Harrison’s Principles of Internal Medicine, says that triple phosphate crystals form struvite (infection) stones, which are shaped like a stag’s horn (branched). Treatment includes the surgical removal of the kidney stones and eradicating any infection with antibiotics.