Physical Examination

• Required urine volume for routine urinalysis: 10 to 15 mL, but collection of a larger volume is encouraged to ensure sufficient urine for additional or repeat testing
• Smaller volumes of urine (<12 mL), hinder performance of the microscopic examination when the urinalysis is performed manually and can limit the chemical tests performed
• Urine container capacity for routine urinalysis: 50 mL
• Types of examinations under urine urinalysis

  • Physical Examination
  • Chemical Examination
  • Microscopic Examination
• Average volume of urine for routine urinalysis: 12 mL
• Required volume range of urine for routine urinalysis: 10-15 mL
• Urine container capacity for drug testing: 60 mL
• Required volume of urine for drug testing: 30-45 mL
• Physical urinalysis


  Observation of these characteristics provides preliminary information concerning disorders, such as glomerular bleeding, liver disease, inborn errors of metabolism, and urinary tract infection
• Measurement of specific gravity aids in the evaluation of renal tubular function
• Urine color


  Serves as an indicator of how well hydrated a person is; it gives a rough estimate of urine concentration
• If a person keeps on drinking water, they will have a colorless to pale yellow urine
• Color variation may be due to normal metabolic functions, physical activity, ingested materials, or pathologic conditions
• Normal urine color common description

  • Pale yellow
  • Yellow
  • Dark yellow
  • Amber
• Urochrome


  A product of endogenous metabolism, and under normal conditions, the body produces it at a constant rate. Amount produced is dependent on the body's metabolic state. Increased in thyroid conditions, fasting states, fever and long standing at room temperature. Major pigment of urine.
• Uroerythrin


  In refrigerated specimen resulting in the precipitation of amorphous urates in an acid urine (pink sediments/ brick-red dust). Attached to the urates, producing a pink color to the sediment.
• Urobilin


  Oxidation product of urobilinogen (colorless). Imparts an orange-brown color to urine that is not fresh.
• Urine Color and Clarity Procedure

  • Evaluate an adequate volume of specimen
  • Use a well-mixed specimen
  • View the urine through a clear container
  • View the urine against a white background using adequate room lighting
  • Maintain adequate room lighting
  • Evaluate a consistent volume of urine
  • Determine the urine color
• Abnormal urine color


  • Red, red brown
  • Dark yellow/ Amber/ Orange
  • Pink/ Brown
  • Blue/ Green
• Causes of colorless to pale yellow urine

  • Recent fluid consumption (inc. alcohol)
  • Polyuria
  • Diabetes insipidus
  • Diabetes mellitus
• Causes of dark yellow, amber, yellow brown urine

  • Mepacrine (yellow) (anti-malarial drug)
  • Riboflavin (bright yellow) (Vit. B2)
  • Concentrated specimen (inc. urochrome)
  • Bilirubin (has yellow foam)
  • Urobilin
  • Acriflavine (anticoagulant)
  • Nitrofurantoin (antibiotic for UTI)
• Causes of orange, orange-red urine

  • Phenazopyridine (Pyridium) (for UTI, has a yellow foam that is sometimes mistaken as bilirubin)
  • Phenindione
  • Carotene
  • Warfarin (coumadin) (anticoagulant)
  • Rifampin (antibiotic for TB)
• Causes of dark yellow-green, yellow brown urine

  • Bilirubin oxidized to biliverdin
• Urine foam


  Foam is not reported in routine urinalysis but it can serve as a preliminary or supportive evidence for physical examination of urine.
• Yellow foam


  Bilirubin (conjugated) - Bilirubin 2. Bilirubin 1 is conjugated with albumin and once it passes through the glomerulus it will not be filtered because albumin is big thus it will not be excreted in the urine. Phenazopyridine (brand name: pyridium) - yellow foam, bright-orange urine
• White, stable foam


  Concentrated urine, Presence of protein
• Phenazopyridine


  Thick, orange pigment not only obscures the natural color of the specimen but also interferes with chemical tests that are based on color reactions. Specimens containing phenazopyridine produce a yellow foam when shaken, which could be mistaken for bilirubin.
• Causes of pink/brown urine

  • Presence of blood
  • Glomerular bleeding
  • RBCs in urine; red and cloudy
  • Hemoglobin and Myoglobin; red urine & (+) for blood chemical test
• Hemoglobinuria and myoglobinuria


  May be possible by examining the patient's plasma. Fresh urine containing myoglobin frequently exhibits a more reddish-brown color than does urine containing hemoglobin.
• Nonpathologic causes of red urine


  • Menstrual contamination
  • Ingestion of highly pigmented foods and/or medications
  • Ingestion of blackberries can produce a red color in acidic urine
  • Medications: Rifampin, Phenolphthalein, Phenindione, and Phenothiazines
• Causes of red to brown, brown, dark brown, black urine

  • Phenol derivatives
  • Levodopa
  • Methyldopa
  • Metronidazole (for parasitic infection)
  • Hemogentisic Acid (Alkaptunuria)
  • Melanin (Melanoma)
• Causes of green, blue, blue-green urine

  • Pseudomonas
  • Clorets (breath deodorizer)
  • Phenol derivatives
  • Indicans (or purple) (catheter)
  • Azure A
  • Methylene blue
  • Amitriptyline
• Melanin


  Oxidation product of the colorless pigment melanogen, which is produced in excess when a malignant melanoma is present.
• Causes of pink, red urine

  • RBCs
  • Hemoglobin
  • Myoglobin – red to brown
  • Menstruation
  • Beets
  • Blackberries
  • Phenolsolfonpthalein
  • Phenidione
  • Phenothiazines
  • Senna – laxative
• Hematuria, hemoglobinuria, myoglobinuria


  Hematuria - Intact RBC in urine, urine is cloudy pink to red. Hemoglobinuria - Urine is clear red. Myoglobinuria - Examine the plasma of the patient, myoglobin is easily cleared in plasma (reddish-pink plasma)
• Causes of red or brown urine

  • Myoglobin (25 mg/dL) – can only be observed if the myoglobin conc. is greater than or equal to 25 mg/dL
• Port wine or red purple urine

  Porphyrins (clin. sig., porphyria). Porphyria, an inherited dxs in which a person do not have a specific enzymes that are needed to synthesize the heme. If there's no enzyme, it cannot proceed to heme synthesis and porphyrin will appear in urine.
• Homogentisic acid


  A metabolite of phenylalanine, imparts a black color to alkaline urine from patients with the inborn error of metabolism, called alkaptonuria.
• Medications which produces brown/black urine

  • Levodopa
  • Methyldopa
  • Phenol derivatives
  • Metronidazole (for parasitic infection)
• Causes of blue/green urine

  • Bacterial infections (urinary tract infection by Pseudomonas aeruginosa and intestinal tract infections, resulting in increased urinary indicant) indoxyl potassium sulfate
  • Ingestion of breath deodorizers (Clorets)
  • Methocarbamol (Robaxin), methylene blue, amitriptyline (Elavil)
  • Phenol derivatives found in certain IV medications