ppt t3

• Gross/Physical Examination of Urine


  Macroscopic parameters in urinalysis
• Color


  Pigments that provide the yellow, pink, orange-brown, blue/green, red/pink/brown, and brown/black colors of urine
• Color and Clarity Procedure


  1. Color

  2. Clarity

  3. Specific gravity

  4. Volume

  5. Odor
• Normal urine color


  • Varies from almost colorless, straw or light yellow to dark yellow, yellow-orange or amber
• Pathologic causes of urine color

  • Colorless/Pale Yellow
  • Dark Yellow/Amber/Orange
  • Blue/Green
  • Red/Pink/Brown
  • Brown/Black
• Nonpathologic causes of urine color


  • Colorless/Pale Yellow
  • Dark Yellow/Amber/Orange
  • Blue/Green
  • Red/Pink/Brown
  • Brown/Black
• Bilirubin


  Early indication of liver disease, presence or absence used in determining cause of clinical jaundice
• Urobilin


  Similar to bilirubin in appearance, but shaking the urine specimen -> no yellow foam
• Phenazopyridine (Pyridium)


  Drug commonly used for UTI, thick orange pigment that obscures natural color and interferes with chemical tests based on color reactions
• Pathologic causes of blue/green urine

  • Pseudomonas
  • Biliverdin
  • Indicanuria
• Nonpathologic causes of blue/green urine


  • Amitriptyline
  • Methocarbamol
  • Clorets
  • Methylene blue
  • Phenol derivatives
• Pathologic causes of red/pink/brown urine


  • Intact RBCs
  • Hemoglobin
  • Myoglobin
  • Porphyrin
• Nonpathologic causes of red/pink/brown urine

  • Menstruation
  • Rifampin
  • Phenolphthalein
  • Phenindione
  • Beets
  • Blackberries
• Porphyrias


  Disorder of porphyrin metabolism, failure to inherit the gene that produces an enzyme needed in the metabolic pathway
• Pathologic causes of brown/black urine


  • Homogentisic acid (Alkaptonuria)
  • Melanin (Malignant melanoma)
  • Methemoglobin
• Nonpathologic causes of brown/black urine


  • Argyrol
  • Levodopa
  • Methyldopa
  • Metronidazole
  • Phenol derivatives
• Alkaptonuria


  Inborn error of metabolism, failure to inherit homogentisic acid oxidase
• Melanuria


  Overproliferation of melanocytes ->malignant melanoma
• Methemoglobin


  Acidic urine, oxidation of hemoglobin to brown methemoglobin
• Clarity


  The transparency or turbidity of a urine specimen
• Pathologic causes of turbidity

  • Bacteria
  • WBCs
  • RBCs
  • Lymph fluid
  • Yeast
  • Lipids
  • Abnormal crystals
  • Nonsquamous epithelial cells
• Nonpathologic causes of turbidity


  • Mucus
  • Fecal contamination
  • Amorphous phosphates, carbonates, urates
  • Radiographic contrast media
  • Semen, spermatozoa
  • Talcum powder
  • Squamous epithelial cells
  • Vaginal creams
• Specimens that are allowed to stand will develop turbidity that is nonpathologic, due to improper preservation and bacterial growth
• Amorphous urates produce a precipitate in refrigerated acidic urine that resembles pink brick dust due to the presence of uroerythrin, and dissolve if warmed to 60'C
• Amorphous phosphates and carbonates produce a white precipitate in refrigerated urine with an alkaline pH, and dissolve if acetic acid is added
• Specific Gravity


  Reabsorption is often the first renal function to be impaired, the kidney's ability to concentrate the glomerular filtrate by selectively reabsorbing essential chemicals and water from the glomerular filtrate
• Causes of hyposthenuric urine


  • Diabetes insipidus
  • Pyelonephritis and glomerulonephritis
• Causes of high specific gravity urine

  • Excess water loss/dehydration
  • Adrenal insufficiency
  • Hepatic disease
  • Congestive heart failure
• pH


  Dissolve if acetic acid is added
• Laboratory Correlations in Turbidity

  • Clear urine is not always normal
  • Questionable causes of urine turbidity can be confirmed by chemical tests
  • The amount of turbidity should correspond with the amount of material observed under the microscope
  • Clarity and chemical tests for RBCs, WBCs, bacteria, protein determine necessity for microscopic examination
• Formative Test 03


  20XX
• Specific Gravity


  The density of a solution compared with the density of a similar volume of distilled water at a similar temperature
• Significance of Specific Gravity


  • Reabsorption is often the first renal function to be impaired
  • The kidney's ability to concentrate the glomerular filtrate by selectively reabsorbing essential chemicals and water from the glomerular filtrate is evaluated by measuring the SG of the spx
  • Detects possible dehydration or abnormalities in ADH
• Specific Gravity


  • Hyposthenuric
  • Isosthenuric
  • Hypersthenuric
• Hyposthenuric


  Causes: Diabetes insipidus (loss of concentrating ability), Pyelonephritis and glomerulonephritis
• Isosthenuric


  Causes: Excess water loss/ dehydration, Adrenal insufficiency, Hepatic disease, Congestive heart failure
• Hypersthenuric


  Causes: Severe renal damage
• SG of glomerular ultrafiltrate: 1.010
• Normal Random SG: 1.002-1.035 (Ave. 1.015-1.030)
• Normal 24-hr SG: 1.015-1.025