04. Physical and Macroscopic Examination of Urine Part 1

600-2000 mL

Normal Urine Volume for 24 hours?

1200-1500 mL

Average volume excreted by an individual?

1:2 to 1:3

Night : Day Ratio

More urine is excreted during the day

oliguria

Abnormal Urine Volume

• Decrease in the urine output

  • < 1 mL/Kg in infants

  • < 0.5 mL/Kg in children

400 mL/day

Abnormal Urine Volume : Oliguria

• Less than _____ in adults

This can be due to;

• Dehydration (vomiting, diarrhea, perspiration, or severe burns.

• Calculus or tumor of the kidney

anuria

Abnormal Urine Volume

• Cessation of urine flow

This can be due to;

• Serious damage to the kidneys

• Decrease in the flow of blood to the kidneys

• Obstruction due to stones or carcinomas

• Toxic agents

nocturia

Abnormal Urine Volume

• Increase in the nocturnal excretion of urine

More urine in the night

polyuria

Abnormal Urine Volume

• increase in daily urine volume

  • 2.5 - 3 mL/Kg/day in children

2.5 L/day

Abnormal Urine Volume: Polyuria

• Greater than ____ in adults

This can be due to;

• diabetes mellitus and diabetes insipidus (Read Notes)

• diuretics, caffeine, or alcohol

• Increased fluid intake

• nervousness

white

Urine color, examine the specimen under a good light source, looking down through the container against a _______ background

urochrome

• Yellow pigment of normal urine

• Product of endogenous metabolism excreted at a constant rate

Primary urine pigment.

Darker urine = concentrated meaning urochrome is elevated.

Pale yellow = urochrome is decreased.

uroethryn

• Pink pigment

• Attaches to amorphous urates

  • Urates can be seen in ACIDIC urine (Pink)

  • Amorphous phosphates can be seen in ALKALINE urine (White)

• Most evident in refrigerated specimen

urobilin

• Oxidation product of urobilinogen

• Orange-brown color imparted to urine that is not fresh

For the metabolism of bilirubin, check notes!

Pale yellow

Laboratory Correlation of Urine Color

• Polyuria or diabetes insipidus

• Diabetes mellitus

• Dilute random specimen

Dark yellow

Laboratory Correlation of Urine Color

• Concentrated specimen

• B complex vitamins

• Dehydration

• Bilirubin

• Acriflavine (Board exam recall)

• Nitrofurantoin (Medication for UTI)

Bubbling:

• When urine is shaken and white bubbles appear that persist long = Proteins/Albumin Present

• When urine is shaken and Yellow foam appear = Bilirubin (Not confirmatory)

Orange-yellow

Laboratory Correlation of Urine Color

• Phenazopyridine (Medication for UTI)

• Phenindione

• Sulfasalazine

yellow-green

Laboratory Correlation of Urine Color

• Bilirubin oxidized to biliverdin

Green

Laboratory Correlation of Urine Color

• Pseudomonas Infection

• Asparagus

Blue-green

Laboratory Correlation of Urine Color

• Amitriptyline

• Methocarbamol

• Clorets

• Indican

• Methylene blue

• Phenol (Board exam recall) (When oxidized)

• Propofol

• Familial hypercalcemia (Blue-diaper syndrome)

• Indomethacin

pink or red

Laboratory Correlation of Urine Color

• RBCs

• Hemoglobin

• Myoglobin

• Beets

• Rifampin (TB medication) (Recall)

• Menstrual contamination

If we see clumps of RBCs in urine specimen = Hematuria

• But this could also indicate the presence of hemoglobin or myoglobin.

How to differentiate?

• Clarity

  • Turbid/Hazy: Hematuria

  • Clear: Hemoglobinuria/Myoglobinuria

How to differentiate Hemoglobinuria and Myoglobinuria?

• Plasma

  • Red: Hemoglobinuria

  • Normal Color : Myoglobinuria

port wine

Laboratory Correlation of Urine Color

• Porphyrins

red brown

Laboratory Correlation of Urine Color

• RBCs oxidized to methemoglobin

  • Especially if our urine pH is acidic

• Myoglobin

brown black

Laboratory Correlation of Urine Color

• Homogentisic acid (alkaptonuria)

• Malignant melanoma melanin or melanogen

• Phenol derivatives

• Argyrol

• Methyldopa or levodopa

• Metronidazole

• Chloroquine and primaquine

• Methocarbamol

• Fava beans, rhubarb, or aloe

mixed

• Clarity, is a general term for transparency or turbidity

• It is determined by examining _____ specimen while holding it in front of a light source

• Should correspond to the amount of material observed microscopically.

Clear

Urine Clarity

• No visible particulates, transparent

Hazy

Urine Clarity

• Few particulates, print easily seen through urine

Cloudy

Urine Clarity

• Many particulates, print blurred through urine

Turbid

Urine Clarity

• Print cannot be seen through urine

Milky

Urine Clarity

• May precipitate or be clotted

Nubecula

Urine Clarity

• Clear urine has cloud formation, that is usually caused by WBC, epithelial cells and mucus threads that are clumped to each other.

non pathologic

Causes of Urine Turbidity

• Squamous epithelial cells (seen in female)

• Mucus (seen in female)

• Amorphous phosphates, carbonates, urates

• Semen, spermatozoa

• Fecal contamination

• Radiographic contrast media

• Talcum powder

• Vaginal creams

pathologic

Causes of Urine Turbidity

• RBCs

• WBCs

• Bacteria

• Yeast

• Trichomonads

• Non-squamous epithelial cells

• Abnormal crystals

• Lymph Fluid

• Lipids

acidic urine

Correlations on Turbidity

• Amorphous Urates

• Radiographic contrast media

alkaline urine

Correlations on Turbidity

• Amorphous phosphates

• Carbonates

soluble at 60 C

Correlations on Turbidity

• Amorphous urates

• Uric acid crystals

soluble in dilute acetic acid

Correlations on Turbidity

• RBCs

• Amorphous phosphates, carbonates

insoluble in dilute acetic acid

Correlations on Turbidity

• WBCs, bacteria, yeast and spermatozoa

soluble in ether

Correlations on Turbidity

• Lipids, lymphatic fluid, chyle