COLOR
Normal Varies from almost colorless; straw or light yellow (low SG, increased volume) to dark yellow, yellow-orange, or amber
Pigments in Urine a. Urochrome – product of endogenous metabolism; increases in urine at room temperature
b. Uroerythrin – pink pigment seen in refrigerated urine due to precipitation of amorphous urates
c. Urobilin – oxidation product of urobilinogen; imparts an orange-brown color to urine
Variations a. Colorless / pale yellow – recent fluid consumption, polyuria DI, DM, alcohol consumption
b. Dark-yellow – concentrated specimen
c. Orange-red / reddish brown – urobilin
d. Amber / orange – bilirubin, acriflavine, phenazopyridine, nitrofurantoin, phenindione
e. Yellow-green / yellow-brown – bilirubin-biliverdin
f. Blue / green – pseudomonas infection, amitriptyline, methocarbamol, clorets, indican, methylene blue
g. Pink / red – intact RBCs, hemoglobin, myoglobin, porphyrins, beets, menstrual contamination
h. Brown / black – methemoglobin, homogentisic acid, melanin, phenol derivative, argyrols, methyldopa, levodopa, metronidazole
ODOR
Normal Faint aromatic, due to volatile acids; becomes ammoniacal as the specimen stands
Variations a. Ammoniacal (freshly voided) – UTI, (Proteous and other urease-producing bacteria)
b. Mousy – PKU
c. Rancid – Tyrosinuria
d. Sweaty feet – Isovaleric academia
e. Maple syrup / caramel-like – MSUD
f. Rotting fish – Trimethyl aminuria
g. Sulfur odor – cysteine disorders
h. Fecaloid – recto-vesicular fistula
i. Fruity / sweet – diabetes ketoacidosis (acetone or diacetic acid)
j. Cabbage / hops – methionine malabsorption
k. Mercaptan – ingestion of asparagus, garlic and eggs
l. Bleach - contamination
TRANSPARENCY
Normal Clear – no visible particulates, transparent
Variations a. Hazy – few particles, print easily seen through urine
b. Cloudy – many particulates, print blurred through urine
c. Turbid – print cannot be seen through urine
d. Milky – may precipitate or be clotted
NUBECULA
Faint, whitish cloud formed from mucus, cells, bacteria, and alkaline salts in old urine.
Non-pathologic causes of Turbidity Pathologic Causes of Turbidity
Epithelial Cells Red blood cells – 500/mm3
Normal crystal White blood cells- 200/mm3
Bacteria (old urine) Bacteria, yeasts
Semen, prostatic fluid Non-squamous epithelial cells
Fecal contamination Abnormal crystals, casts
Mucus Lymph fluid/chyle
Radiographic contrast media Lipids
h. Vaginal creams, talcum powder Fecal matter