Hematuria is either the microscopic or the macroscopic presence of blood in the urineGross Hematuria
Gross hematuria is suspected because of red or brown urine. The color change does not necessarily reflect the degree of blood loss as little as 1 mL of blood per liter
The initial step in the evaluation of patients with red urine is centrifugation of the specimen to see if the red color is in
Hematuria is responsible for the red colour if the red color is seen only in the urine sediment, with the supernatant being clear.
If the supernatant is red, then the supernatant should be tested for heme with a urine dipstick. A red supernatant that is negative for heme is a rare finding that can be seen in several conditions, including porphyria, the use of the bladder analgesic phenazopyridine, and the ingestion of beets in susceptible subjects.
A red supernatant that is positive for heme is due to myoglobinuria or hemoglobinuria.
Beeturia refers to the presence of red urine after the ingestion of beets. It occurs in approximately 14 percent of people and is due to the excretion of the reddish pigment betalaine (betanin). Beeturia appears to be more common in the following conditions:
Uncorrected Iron deficiency
Achlorhydria due to pernicious anemia
Concurrent ingestion of oxalate-containing foods (spinach, oysters)
Microscopic hematuria may be discovered by accident when blood (either red blood cells or hemoglobin) is found on a urinalysis or dipstick done for other purposes. Hematuria is commonly defined as the presence of more than 2 RBCs per high powered field in a spun urine sediment.
Hematuria may be a symptom of an underlying disease, some of which are life threatening or treatable. The most common causes are inflammation or infection of the prostate or bladder. Kidney stones, malignancy, and glomerular diseases account for most of the remaining cases. Benign prostatic hyperplasia (BPH) is not a significant cause of hematuria. Symptoms of BPH should not dissuade the clinician from pursuing further evaluation.