Intro To Urinalysis Flashcards
This substance causes absorption of Na from the lumen of the collecting duct
Aldosterone
This substance indirectly stimulates the production of aldosterone
Renin
ADH is produced by ______
Hypothalamus
This substance is responsible for making the collecting duct more permeable to passive water movement out of the lumen by inserting aquaporins
ADH
Urine is an ultrafiltrate of the _____
Plasma
The outer cortex of the kidney is the location of what 3 things?
Location of glomeruli (where filtration occurs), proximal convoluted tubules, and distal convoluted tubules
What is located inside the medulla?
Renal pyramid (loops of henle inside this) and sinus (with minor calyces that merge to form the major calyx)
Basic functional unit of the kidney
Nephron
Responsible for production of the filtrate; located at the proximal end of the proximal tubule
Glomerulus
The filtrate initially collects in _______ ______ due to hydrostatic differences between the lumen of the adder end arteriole and Bowman’s space
Bowman’s Space
After urine leaves the glomerulus it has approximately the same specific gravity as _______; this is known as _______
Plasma ; isothenuria
What is the specific gravity of plasma?
1.010
Significantly reduces the volume of water in the filtrate by reabsorbing approximately 2/3; Na, Cl, Glucose, and Amino Acids are absorbed from filtrate; removes unfiltered proteins or drugs out of blood; secretes H
Proximal convoluted tubule
This tissue surrounds the Loops of Henle in the medullary of the kidney; hypertonic to the filtrate
Medullary interstitium
In this area water moves out of the lumen, it is permeable to urea, and impermeable to Na and Cl
Descending limb of Loops of Henle
In this area Na and Cl are actively moved out of the lumen, it is impermeable to water, and permeable to urea
Ascending limb of the Loops of Henle
In the presence of aldosterone, Na is actively transported out of the lumen (water follows) in what area of the nephron?
Distal convoluted tubule
This determines the final concentration of urine
Collecting duct
JGA senses decreases in ____\______ ______ and releases renin which stimulates the production of angiotensin II which in turn stimulates the adrenal cortex to secrete aldosterone
Na\Blood Volume
Aldosterone actively increases _____ ______ from the lumen of the distal convoluted tubule and collecting duct and thus ______ pulls water out of the lumen. _______ is secreted into the lumen.
Na absorption; passively; potassium
_______ in the heart sense a drop in blood pressure, increase in plasma osmolality, and/or exposure to aldosterone
Baroreceptors
The ______ synthesizes ADH which is transported to the pituitary gland for storage before it is released into the bloodstream
hypothalamus
ADH causes changes in the epithelium of the _____ ______ _____ and _____ ______ that enhance the passive flow of water out of the lumen
distal convoluted tubule and collecting duct
Patient with decreased blood pressure will compensate by doing what?
Producing more aldosterone
List the three primary pigments found in urine
Urochrome, urobilin, and uroerythrin
this is the primary source of yellow coloration and is produced at a constant rate
Urochrome
this is an orange-brown colored pigment formed by the oxidation of urobilinogen; common in old urines
urobilin
this is a pink pigment that attaches to urates in the urine and gives amorphous urates a pinkish hue
uroerythrin
Yellow foam in urine is most commonly due to what?
bilirubin and drugs such as pyridium
this is a drug used to reduce discomfort in UTIs, causes very orange urine obscuring chemical testing
pyridium
What 3 things are reported on urine containing pyridium?
Color, clarity, and specific gravity (by refractometer)
Fresh and intact RBCs cause urine color to be what?
Pink—>Red
How does Hemoglobin and myoglobin appear in urine?
urine is clear, reagent strip positive for blood
_____ in the urine is often accompanied by a reddish plasma
hemoglobin
_______ in the urine is often accompanied by a clear plasma because it is cleared from the blood quicker
myoglobin
accumulation of uroporphyrin causing port wine colored urine, color may be red but the strip may read negative
porphyria cutanea tarda
accumulation of coproporphrinogen, red or colorless urine with fluorescence
lead poisoning
Brown, Dark Brown, or Black urine can be caused by what 3 things?
Melanuria (melanin in urine), Alkaptonuria (homogenistic acid), medications
Green or yellow/green urine is caused by what?
biliverdin (an oxidized form of bilirubin), bacterial infections (pseudomonas), or medications
What does normal urine clarity look like?
clear
List some non-pathogenic states of urine clarity
amorphous phosphates, carbonates, and urates precipitate out during refrigeration; squamous epithelial cells from an improper collection; improper storage allowing for excessive bacteria growth; contamination with sperm, talcum powder, vaginal creams, radiographic contrast, fat or chyle
List some pathologic states from cloudy urine
bacteria, yeast, fungi, red blood cells, white blood cells, trichomonas, fecal contamination
a ratio between the density of urine and the density of distilled water at the same temperature; a measure of the kidney’s ability to maintain the body’s water and chemical balance through reabsorption
specific gravity
Specific gravity measures the amount of ______ _______
dissolved solids
What is the chemical that is primarily responsible for urine coloration?
urochrome
Principle: ratio of the velocity of light through air is compared to the velocity of light through a solution
Refractometer
How do you correct the specific gravity in a refractometer for glucose?
for every gram of glucose/dL subtract 0.004
How do you correct the specific gravity in a refractometer for protein?
for every gram of protein/dL, subtract 0.003
How can the concentration of glucose and protein be determined?
by the reagent strip
Why does using centrifuged or uncentrifuged urine not affect the specific gravity when using a refractometer?
because we are measuring dissolved substances
