Urine studies, such as urinalysis and urine osmolality, can indicate urinary tract infection (UTI) and other disorders.
Urinalysis is performed on a urine specimen of at least 10 ml, urinalysis can indicate urinary or systemic disorders, warranting further investigation.
• Collect a random urine specimen, preferably the first-voided morning specimen. Send the specimen to the laboratory immediately.
• Refrigerate the specimen if analysis will be delayed longer than 1 hour.
Urine osmolality Study:
Urine osmolality evaluates the diluting and concentrating ability of the kidneys. It may aid in the differential diagnosis of polyuria, oliguria, or syndrome of inappropriate antidiuretic hormone secretion. To gather more information about the patient’s renal function, compare the urine specific gravity with urine osmolality.
• Obtain a random urine specimen.
• Keep in mind that urine osmolality typically ranges from 50 to 1,400 mOsm/kg, with the average being 300 to 800 mOsm/kg.
Urine Color Study:
The color of the urine is the easiest way to determine someone’s hydration status. Surprisingly, it can indicate other aspects of health as well.
Yellow-Amber: Normal urine varies from very clear yellow to a darker amber color. Generally speaking, the less hydrated you are – the more concentrated your urine is with nitrogenous waste and electrolytes – thus darker urine. The more hydrated you are, the more dilute it is, leading to clear yellow urine. The first void of the morning is typically darker and more concentrated – this is normal. However, darker urine throughout the day should prompt an increased need to drink water.
Red: When we see red urine – we typically think of blood. And that may be the case in many different situations such as kidney stones (nephrolithiasis), UTIs, or glomerular damage. As little as 1mL of blood can cause a color-change, and the presence of red urine does not automatically mean large amounts of blood. Rhabdomyolysis can also cause myoglobin in the urine which has a red-brown appearance as well. However, there are various other factors which can cause red urine including certain foods such as Beets, Blackberries, and rhubarb; as well as different medications such as Propofol, Chlorpromazine, or Ex-Lax.
Orange-Red: You may see a neon orange-red from the antibiotic Rifampin used in the treatment of TB, or phenazopyridine (pyridium) used to treat bladder burning and discomfort during a UTI.
Other crazy colors: Other foods, drugs, and disease processes can turn urine every color of the rainbow. Certain UTIs can cause Green or purple urine, Fava beans can cause brown urine, amitriptyline or IV promethazine can cause blue urine. While these are very interesting, they are also super uncommon and you probably don’t need to commit them to memory.
Urinalysis Lab Study:
Urinalysis is analysis of a urine specimen to determine characteristics, such as:
• presence of red blood cells (RBCs)
• presence of white blood cells
• presence of casts or bacteria
• specific gravity and pH
• physical properties, such as clarity, color, and odor.