What is the reason for high crystallinity in urine routine test

If the urine routine shows high crystals, we should pay attention to understanding the causes, because we all know that high urine crystals can be physiological or pathological, so of course we need to pay attention to scientific solutions for different causes. The most common physiological causes are calcium oxalate crystals, or uric acid crystals and non-crystalline urate, so we must have a scientific understanding of these symptoms.

1. Cause of crystallization

Whether crystals precipitate in urine depends on factors such as the solubility of these substances in urine, pH, temperature and colloid state. When the factors that promote and inhibit the precipitation of crystals and the factors that cause excessive urine drinking and maintain a stable dynamic balance are unbalanced, crystal precipitation can be seen. Crystals in urine can include both physiological and pathological types.

2. Physiological

1. Calcium oxalate crystals: colorless square glittering octahedron or envelope-like, with two diagonal lines crossing each other, sometimes rhombus-shaped, occasionally dumbbell-shaped or pie-shaped, similar to red blood cells, crystals are soluble in hydrochloric acid but insoluble in acetic acid and sodium hydroxide. If fresh urine contains a large amount of calcium oxalate crystals accompanied by red blood cells, and there are symptoms of kidney or bladder irritation, it is usually a sign of kidney or bladder stones.

2. Uric acid crystals: yellow or dark brown in color, with shapes of rhombus, dumbbell, butterfly or irregular. Uric acid crystals dissolve in sodium hydroxide solution but are insoluble in acetic acid or hydrochloric acid. Adding ammonia water to dissolve them will form ammonium urate crystals. The increased uric acid concentration in the urine causes a large amount of uric acid to precipitate in the renal tubules and interstitium, which can produce hyperuricemia nephropathy and uric acid stones, causing renal tubular obstruction and tubulointerstitial lesions. Hyperuricemia can also be seen in cases of tubular reabsorption disorder, which can cause renal failure. High uric acid can also be seen in acute gout, acute fever in children, chronic interstitial nephritis, etc.

3. Non-crystalline urate: It is mainly a mixture of sodium urate, potassium urate and calcium urate. It appears as a yellow non-crystalline granular precipitate. It is colorless in light urine and easily precipitates in low temperature, concentrated urine or highly acidic urine.

4. Hippuric acid crystals: often appear in the shape of colored needles, plates, rhombuses or diamonds. This crystal is a normal component of the urine of humans and herbivores, and its content in herbivores' urine is higher. It is composed of benzoic acid and glycine.