Final answer:
To distinguish hematuria from hemoglobinuria in a urine sample, one can centrifuge the sample or allow it to settle. Red blood cells in hematuria will form a sediment at the bottom, while the supernatant in hemoglobinuria will remain colored due to the dissolved hemoglobin.
Step-by-step explanation:
Distinguishing Hematuria from Hemoglobinuria
To distinguish between hematuria and hemoglobinuria in a fresh urine sample, one can rely on centrifuging the sample or simply letting it settle. Hematuria, which is the presence of red blood cells (RBC) in the urine, can occur in conditions such as nephritis, kidney trauma, tuberculosis of the kidney, and kidney stones. Hemoglobinuria, on the other hand, is characterized by the presence of free haemoglobin in the urine, which can result from conditions like malaria, kala-azar, and typhoid.
When urine is centrifuged, the RBCs in cases of hematuria will settle at the bottom, forming a sediment. If the supernatant fluid remains clear, this suggests that the cloudiness was due to RBCs. In contrast, if the urine colour remains red or brown after centrifugation, this indicates hemoglobinuria, as the haemoglobin being dissolved in the urine does not form sediment.
There should normally be no blood in the urine, and urinalysis is a critical tool to diagnose renal diseases. The color of urine is a key factor in urinalysis and is significantly influenced by the breakdown of red blood cells that produce a compound called urochrome. A variety of factors can alter the color of urine, including certain foods, liver diseases, and dehydration, which could lead to misinterpretation of results if not taken into account.