Urinalysis Flashcards
Falconi Syndrome
Affects kidneys
Excessive excretion of glucose, amino acids, phosphate, etc into urine
Uremia
Kidneys fail to properly filter waste products from blood
Homogentisic acid
- Causes brown/black urine
- Maple syrup urine disease (MSUD)/alkaptonuria
Polyuria caused by
> 2500 ml/day
- Diabetes mellitus/insipidus
- Diuretics
- Caffeine
- Alcohol
- Excessive fluid intake
Oliguria caused by
<400 mg/dl
- Dehydration from: v/d, burns, perspiration
Nocturia caused by
Increased volume at night
- Renal disease
- Pregnancy
- Enlarged prostate
Anuria caused by
No urine output
- Kidney damage
- Decreased blood flow to kidneys
Major functional unit of the kidney
Nephron (composed of glomerulus & renal tubules)
Glomerulus function
Filters water, glucose, electrolytes, amino acids, urea, uric acid, creatinine, and ammonia
Urea
Metabolic waste product produced in the liver
Protein —> urea (breakdown of protein)
What urine sample collection method(s) should you use for culture?
Suprapubic aspiration and midstream clean catch
What urine sample method should you use for screening tests?
First morning (most concentrated)
What is increased when you leave urine at RT for a prolonged time?
Turbidity, pH, nitrite
What is decreased when you leave urine at RT for a prolonged time?
Glucose, ketones, bilirubin, urobilinogen, cells (WBC & RBC) and casts (lysis)
Porphyrin - urine color?
Port wine
Black/brown urine color caused by?
Homogentisic acid, melanin, metHgb
Yellow/amber/orange urine caused by?
- Bilirubin
- Urobilin
- Biliverdin (yellow-green)
- Vitamin C
Green/blue urine caused by?
- Pseudomonas
- Chlorophyll
- Indican
Red urine caused by?
- Hgb
- RBC
- myoglobin (from muscle)
Diabetes mellitus vs diabetes insipidus
- SG increased in DM, decreased in DI
- Glucose and ketones increased in DM, normal in DI
- Decreased insulin in DM, decreased ADH in DI
What is an antidiuretic hormone?
Regulates water balance (kidneys retain water, reducing urine production)
So low ADH = too much urine output (diabetes insipidus = low ADH = needing to urinate a lot)
Ascorbic acid causes false (-) in:
- Glucose
- Blood
- Bilirubin
- Nitrite
Bleach causes a false (+) in:
- Glucose
- Blood
- Leukocytes
Glomerulonephritis
Inflamed glomerulus
- RBC casts
Nephrotic Syndrome
Kidneys not functioning properly (damaged), lets protein in
(+++) protein
Lipid droplets, oval fat bodies
Pyelonephritis
Kidneys infected with bacteria
- leukocyte esterase, nitrite
- WBC casts
End stage renal disease
Gradual loss of kidney function
- Specific gravity fixed at 1.010
- ALL casts, especially broad waxy casts
Renal calculi (kidney stones)
- Calcium oxalate and cystine crystals
Lower UTI
- leukocyte esterase, RBC, nitrite
- NO casts or RTE because it’s below the kidneys
Abnormal acidic crystals
- Leucine, tyrosine, cystine, cholesterol, bilirubin
Creatinine clearance formula
(U x V) / P
U = urine creatinine conc
V = volume of urine
P = plasma creatinine conc
