post lab discussion: exp 9 Flashcards
functions of the kidney
❑ excretion of wastes in the form of urine
❑ regulation of blood volume and pressure through the production of urine
❑ regulation of concentration of major ions in the body
❑ regulation of extracellular fluid pH
❑ regulation of red blood cell synthesis through hormonal control with the hormone erythropoietin
❑ regulation of vitamin D synthesis
what is the purpose of urinalysis
provides many useful information about various diseases and
conditions
- generally easily available and relatively inexpensive simple test
why is called “a poor man’s kidney biopsy”
[bcs it can provide a lot of information about kidney health and other internal conditions without needing an expensive or invasive procedure like a kidney biopsy.]
because of the plethora (a lot) of
information that can be obtained about the health of the kidney or other internal diseases
how much of urine should be collected
30 to 60 mL clean catch or the midstream urine collection (should be freshly collected)
- sample should be taken to the laboratory for analysis, typically within one hour of collection
what happens if transportation to the lab could take more than one hour
sample may be refrigerated
what are the different types of examinations in urinalysis
o Physical examination
o Chemical examination
- the urine sample is tested for the presence of certain chemical substituents
o Microscopic examination
- we are not registered to these
substances that are not normally present in urine
- serum proteins
- glucose
- ketones
- bicarbonate ions
- oxalate ions
what are the composition of urine
❑ mostly water with 5% dissolved substances:
* ammonia and organic compounds (urea, uric acid)
* proteins from pathogens and drugs
* ions (H, Na, K, Ca, Cl, PO4, SO4)
physical characteristics
odor/ smell -
color -
clarity -
pH -
odor/ smell - odorless or can be slightly pungent
color - typically light yellow
clarity - no cloudiness
pH - usually acidic (pH 6) but can range from 4.5 to 8.0
color of urine:
dark urine -
red urine -
orange or tea-colored -
tea-colored -
dark urine - dehydrated
red urine - hematuria (red blood present in urine)/ menstruation
orange or tea-colored - muscle breakdown
tea-colored - liver disease
*certain medication may also change the color of the urine
clarity of urine:
cloudy -
very foamy -
cloudy - infection
very foamy - large amts of proteins in the urine (proteinuria)
what are some substances that cause cloudiness in urine but are not considered unhealthy
mucus
sperm and prostatic fluid (men)
cells from the skin
normal urine crystals
contaminants like body lotions and powders
what substances that causes cloudiness in the urine that requires attention
RBCs
WBCs
bacteria
what is the role of kidneys
maintain acid-base balance of the body
in the production of acids/ bases,
it is high in pH in urine -
it is low in pH in urine -
it is high in pH in urine - alkalosis
it is low in pH in urine - acidosis
true or false:
ingestion of acidic/ basic foods does not directly affect urine pH
false - it directly affects
what test tests for
protein -
sugar -
protein - biuret test
sugar - benedict’s test
what are the reagents used for
protein -
sugar -
ketone -
bicarbonate test -
chlorine -
ammonia -
protein - NaOH, CuSO4
sugar - benedict’s reagent (CuSO4 in citrate and carbonate)
ketone - 1:1 mixture of glacial acetic acid and 10% sodium nitroprusside
bicarbonate test - H2SO4
chlorine - HNO3, nitric aid and AgNO3, silver nitrate
ammonia - NaOH, sodium hydroxide
what are the standards for each tests
protein -
sugar -
ketone -
bicarbonate test -
chlorine -
ammonia -
protein - albumin
sugar - glucose
ketone - acetone
bicarbonate test - sodium bicarbonate
chlorine - sodium chloride
ammonia -
what are the positive result for each tests
protein -
sugar -
ketone -
bicarbonate test -
chlorine -
ammonia -
protein -
copper ions in the biuret reagent forms a violet/ blue violet-colored complex with the protein’s peptide bond [complexation]
sugar -
brick red-ppt [redox]
ketone -
+ pinkish
++ red ring
+++ deep purple ring
bicarbonate test -
formation of gas bubbles
chlorine -
formation of whit ppt
ammonia - litmus paper color change (R → B)
what is the reference table for the conc. of proteins (biuret test)
index cards
which test will serve as our
- positive control
- negative control
- positive control
standard - negative control
distilled water
what is the normal result for protein
no protein or very small amt of protein in the urine (micro daw)
elevated urine protein
proteinuria
why do healthy people have temporary or persistent proteinuria
stress
exercise
fever
aspirin therapy
exposure to cold
what happens if the patient repeat testing for urinalysis but shoes that there is still elevated urine protein (proteinuria)
it may a sign of kidney disease (small amt. of urine albumin upon onset of kidney dysfunction)
or it may be associated w many other disease or conditions - will require follow up tests
what s the follow up test if protein is detected in the urine
urine albumin test
- more sensitive test for small amt of proteins
- routinely used to screen people w chronic conditions that put them at risk for kidney disease (diabetes/ hypertension)
what is the reference table for the conc. of sugars (benedict’s test)
index card
what is the normal result for sugar
no glycose in the urine
presence of glucose bcs of either excessive high glucose lvl i blood or a reduction in the “renal threshold”
glucosuria
*reduction in the “renal threshold” - at a certain blood glucose lvl, kidneys begin to eliminate glucose into the urine to decrease blood conc.
*the threshold conc. is reduce and glucose enters the urine sooner, at a lower blood glucose conc.
[Normal situation: The kidneys filter blood and return almost all the sugar back into the body, so no sugar ends up in the urine.
When the sugar is too high: If blood sugar levels go above a certain point (the “renal threshold”), the kidneys can’t reabsorb all of it. The extra sugar spills into the urine to lower the sugar level in the blood.]
what causes glucosuria
hormonal disorders
liver disease
medication
pregnancy
true or false:
fasting blood glucose may be performed to further identify the specific cause
true
(for example, )
what are the ketone bodies
acetoacetate
B-hydroxybutyrate
acetone
*these are intermediate products of fat metabolism
*produced when glucose is depleted as an energy source
(when u r on a low/ zero carbs diet = possible that ketone bodies can detect in the urine)
Sodium nitroprusside (SNP) chemical formula
Na2[Fe(CN)5NO] * 2H2O
(strong oxidizing agent)
the product when SNP reacts with ketone bodies
to form a reddish to purple ring
what is the normal result for ketone bodies
no ketones in urine
presence of high levels of ketones in urine
ketonuria
what causes ketonuria
strenuous exercise
exposure to cold
frequent/ prolonged vomiting
several diseases in digestive system that increases fat metabolism
for the test for ketone bodies, what is the indication when a person has diabetes
early indication of insufficient insulin
- With insufficient insulin, glucose cannot be properly processed and instead, fat is metabolized
- results to build-up of ketones in blood (ketosis) then progressing to ketoacidosis
this results to build-up of ketones in blood
ketosis then progressing to ketoacidosis [a dangerous condition where the blood becomes too acidic, and the kidneys try to get rid of the extra ketones (and glucose) by dumping them into the urine.]
excess ketones and glucose dumped into the urine by the kidneys to eliminate from the body
Diabetic ketoacidosis (DKA)
– usually seen in persons with uncontrolled Type 1 diabetes
equation of carbonate and bicarbonate formation
carbonate:
CO3^2- + 2H+ —> CO2 +H2O
bicarbonate:
HCO3- + H+ —> CO2 + H2O
what can you tell if the bicarbonate levels are higher/lower than normal
it is suggestive of the body’s trouble in maintaining its acid-base balance
what can you infer when
o Highly alkaline blood or tissues =
o Acidic blood or tissues =
o Highly alkaline blood or tissues = significant presence of bicarbonate in urine (alkaline urine)
o Acidic blood or tissues = bicarbonate in the blood = absence of bicarbonate in urine (acidic urine)
what happens of you have
high bicarbonate levels:
low bicarbonate levels:
high bicarbonate levels:
body is having trouble removing carbon dioxide (CO2), either because of problems with the lungs or kidneys.
low bicarbonate levels:
kidney problems, respiratory issues, or conditions where the body is losing too much bicarbonate (like chronic diarrhea or diabetic ketoacidosis)
Common causes of low bicarbonate
Addison’s disease (a problem with the adrenal glands)
Chronic diarrhea
Diabetic ketoacidosis (DKA)
Metabolic acidosis (when the body produces too much acid)
Respiratory alkalosis (too much CO2 is removed, often from hyperventilation)
Shock
Kidney disease
Methanol poisoning
Aspirin overdose
what is the white ppt in the test for chlorine
white ppt is the silver chloride
what are the functions of chloride
o helps keep the balance of amount of fluid inside and outside of the cells
o helps maintain proper blood volume, blood pressure, and pH of the body fluids
*one of the most important electrolytes
true or false;
chloride in urine is not normal
false - it is normal
it is from the salt in the diet
chloride
* it is absorbed by the intestines and excess chloride leaves the body through the urine
why is the chloride test done
The test is often done if you have symptoms like:
Muscle twitching or spasms
Breathing problems
Weakness or confusion
what can the chloride test show
- Kidney or adrenal gland problems: Chloride levels can indicate if there are issues with these organs.
- High blood pH (metabolic alkalosis): If your blood is too alkaline (basic), it might be due to:
- Electrolyte loss from prolonged vomiting or diarrhea
- Excessive loss of sodium or consuming too much baking soda (which contains sodium bicarbonate)
what are the test for ammonia
- Checking liver function: The liver normally helps get rid of ammonia, so if the liver isn’t working well, ammonia levels can rise. This test is done when there are symptoms like:
- Confusion
- Excessive sleepiness
- Coma
- Hand tremors - Monitoring liver disease: It’s used to check how well treatments are working for severe liver disease like cirrhosis.
- Diagnosing Reye’s syndrome: In children, high ammonia levels can help diagnose Reye’s syndrome, a rare condition that can damage the liver and brain.
- Predicting outcomes in liver failure: The test helps doctors understand the prognosis (outlook) for people with acute liver failure.
Monitoring nutrition: It can also be used to check ammonia levels in people who are receiving high-calorie IV nutrition.
how to prepare the test for ammonia
o Do not eat, drink anything other than water, or smoke for 8 hours before having ammonia blood test
o Avoid strenuous exercise just prior to having the test
