Urine color
Normally, urine specimens may appear pale yellow (also known as straw) to amber in color. Urochrome is the substance that provides the traditional yellow color observed in urine.
Urochrome is a pigment that is released continuously as a product of hemoglobin breakdown and normal metabolism. Because the amount of urochrome is consistent, the intensity of the yellow color in the specimen will vary with the patient’s hydration status. Urine specimens that are more concentrated (such as the first morning void specimen) will have a darker yellow color than those that are obtained later in the day, as the patient becomes more hydrated.
The terms used to describe the color of urine may vary slightly among laboratories but it is important that they are standardized within each facility. such as
( pale yellow , yellow, dark yellow, and amber )
It is also important to evaluate urine color on a well-mixed specimen in a clear container so that the true color can be evaluated.
Image shows various colors of urine specimens
A noticeable change in urine color may be caused by
a pathological condition. However, certain foods, vitamins, or medications may also cause an abnormal color.
Table lists potential causes for various urine colorsThe most commonly encountered abnormal colors and their significance are listed here
Dark yellow to amber
Although these colors are technically within the normal range, sometimes urine wil appear dark yellow or amber when bilirubin is present in the specimen. This may indicate liver dysfunction,such as in hepatitis, or other conditions that lead to increased red blood cell destruction. Recent strenuous exercise may also cause urine to appear dark yellow.
Orange
Urine may also appear orange when bilirubin levels are elevated in the specimen. However, a more common cause of bright orange urine is the presence of Pyridium (phenazopyridine), a medication used to treat recurrent urinary tract infections. This medication produces a potent orange pigment that will interfere with many of the testing procedures included in a urinalysis.
Red to brown
The presence of red blood cells (hematuria) in the urine specimen may cause it to appear pink, red, or even brown. Urinary tract infections or renal dysfunction may allow red blood cells to enter the urinary tract. The presence of hemoglobin from increased red blood cell lysis elsewhere in the body also leads to red urine specimens, although the urine is clearer than it is when intact red blood cells are present. Myoglobinis a by-product of muscle destruction, and elevated levels may also cause the urine to appear reddish in color. Many medications, fresh beets, and fresh blackberries may also contribute to a red urine specimen.
Blue or green
Urinary tract infections caused by Pseudomonas bacterial genus may cause the patient’s urine to appear green in color. Various medications may also cause a green or blue hue
Fluorescence
Multivitamins may cause the urine to “fluoresce,” although the urine color may be normal.
Brown or black
Hemoglobin may turn brown in acidic urine that has been left standing for an extended period of time. Brown or black urine may be evident for patients that have melanoma. This is caused by the presence of melanin and melanogen in the specimen.
You can see Urine Clarity from here
Urine Clarity
