What urine findings are characteristic of nephrolithiasis?

The presence of hematuria and certain crystals in urine is characteristic of nephrolithiasis, or kidney stones. When stones form in the urinary tract, they can cause irritation and damage to the lining of the urinary tract, leading to blood in the urine (hematuria). This is often accompanied by the presence of specific crystals, such as calcium oxalate or struvite, depending on the type of stone. Identifying these crystals can help in diagnosing the exact type of kidney stone and guiding treatment options.

In contrast, increased urine output and high bilirubin levels are not typically associated with nephrolithiasis; these findings might suggest different conditions, such as liver dysfunction or hemolysis. Low specific gravity and proteinuria may be indicative of other renal conditions, such as glomerulonephritis. Presence of glucose and ketones in urine suggests diabetes mellitus or starvation rather than kidney stones. Thus, the combination of hematuria and specific crystals is the hallmark finding that directly relates to nephrolithiasis.