Complete Metabolic Panel (CMP) Flashcards
CMP is ___ in frequency of utilization after the CBC
2nd
CMP is most common way to diagnose
diabetes
–when you see high glucose reading, you should evaluate this patient because they may be a diabetic
CMP is also useful to monitor for side effects or ______ from meds or the effect of chronic medical conditions on the ____ +_____
toxicities
kidney +liver
most providers think of labs in a certain order. which are the 2 first?
CBC, CMP
When you think of CMP you primarily think of ____ disease and ____ abnormalities
GI disease
electrolyte abnormalities
if pt is feeling weak/run down, etc. order a
get a CBC and CMP.
If someone is on a med that has a side effect of liver toxicity
Ex: give pt lamocil for toe fungus but it can have harsh side effect on liver/liver toxicity, you should monitor their liver through a
CMP
Components of the Complete/Comprehensive Metabolic Panel
15 things
The baby bunny always crawls around and continues along a perfect calm green sunny cottage
Total Protein BUN Bilirubin ALT Creatinine AST albumin CO2 alkaline phosphatase anion gap potassium Calcium glucose sodium chloride
When looking at electrolyte fan and abnormalities we look at
Sodium, Potassium, Chloride, CO2, Anion Gap, Calcium
When looking at renal fxn we look at
BUN, creatinine
When looking at liver fxn we look at
bilirubin, alkaline phosphatase, AST, ALT, (commonly referred to as LFTs)
When looking at proteins we look at
albumin, total protein
When we monitor diabetes we look at
glucose level
tells you 1 important thing: is pt diabetic or not?
When would we want to know someones electrolyte status?
heart condition, High BP pts, dehydration from intense sports maybe
How do We measure bilirubin in babies
we can see babies with jaundice –> put under heat lamp to decrease jaundice
frequent reasons that Geng orders CMPs
–> In evaluation of abdominal pain to check for elevated liver enzymes, renal dysfunction
For GI tract problems/kidney disease
–> To evaluate for abnormalities of glucose levels in diabetes
–>To evaluate potassium and renal function in the treatment of hypertension
Or just when treating HTN in general
–> To evaluate for liver dysfunction or liver toxicities with medication
Normal Sodium
136-142mEg/L
Normal Potassium
3.5-5 mEg/L
normal glucose
70-110mg/dL
normal BUN
8-23md/dL
normal creatinine
men 0.7-1.3
women 0.6-1.1
mg/dL
bilirubin
0.3-1.2mg/dL
Looking at fluids:
1) Intravascular/Plasma
2) Intracellular
3) Interstitial
what is predominantly in each ?
1) intravascular/plasma =what’s floating in vessels= predominantly Na+ (and also Cl- to balance it out )
2) Intracellular= mostly K+–big player here
3) interstitial fluid= similar to plasma Na+ and Cl- to balance it
Sodium is a predominant cation in the _____ fluid
therefore it is a major determinant of
plasma and interstitial which together= extracellular
osmolality=tonicity which drives sodium reguation
the body maintains sodium homeostasis by
regulating water intake or excretion in the kidneys
So inside cell predominantly _____ and outside cell predominantly _____
K+
Na+
Regulation of Na+ can occur through multiple hormones, including _____ and _____ but Na+ is primarily regulated by _______
aldosterone, naturietic
primary= ADH= ANTI-DIURETIC HORMONE
ADH is produced in the ____ and released by the
hypothalamus
pituitary
ADH is also known as
vasopression
ADH fxns
increases renal free water reabsorption–> so more water reabsorbed, less peeing/diuresis
How to reduce osmolality?
Increase renal free water reabsorption in kidneys
what ADH does
What detects increased osmotic pressure? and what does it mean if it is increased?
osmoreceptors in pituitary
it means too much sodium
this means that BP will go up to increase blood volume/pressure
as plasma water decreases (dehydration), what happens?
you want to CONSERVE WATER
1) so sodium osmolality increases,
2) ADH is secreted to stop you from peeing, and
3) collecting renal tubule reabsorbs more water
increasing ADH _____ diuresis
decreases
as plasma water INCREASES, (hydrated) what happens?
you can get rid of water
1) so sodium and osmolality decrease (dilution)
2) body compensates by decreasing ADH secretion (can pee normally)
3) collecting renal tubule becomes impermeable so water is NOT reabsorbed
Decreasing ADH
pee more
body is very good at homeostasis between sodium intake and ADH so hypernatremia doesn’t occur very often but when it does, it occurs in
unreplaced water loss: specific situations
1) elderly pos who have impaired mental faculties and have diminished thirst stimulation
2) patients not given free access to water or given saline solns (too much of it)
Hyponatremia
can be caused by
1) dietary/nutritional intake (kind of rare to not get enough Na+–but could be from GI issues/diarrhea)
2) thiazide diuretics–make you pee a lot and sodium goes out with the water(chlorthalidone/hydrochlorthalidone)
3) renal insufficiency- not kidney failure, but not working and too much water/Na+ is leaving
Which is more common, hyponatremia or hypernatremia?
hyponatremia
When a patient has hyponatremia, think of
medications, such as diuretics
Thiazides increase water permeability and water reabsorption with an effect that is independent of ADH
Bob is a 35 year old man with a history of hypertension. Four years ago, he was placed on a thiazide-type diuretic, Chlorthalidone 25 mg at dose of 1 daily. Recently, his physician advised him that his BP was still not adequately controlled and he was thinking of placing Bob on a second hypertension medication. Bob was not happy to hear this, so he promised his physician that he would begin an exercise regimen and change his diet. Bob went on a crash diet of chicken, white rice and water. He avoided all fruits and vegetables to He has been exercising in the summer heat without drinking water. Bob is brought into the ER with sudden cardiac arrest
What electrolyte abnormality may have contributed to his event?
Chlorthalidone and Hydrochlorothiazide are two very common thiazide type diuretics that are used 1st line to treat HTN. The most common side effect that you might see is hypokalemia.
Bob also failed to eat any potassium when he changed his diet.
What happened here? he decreased his K+ in what he eats and he’s on chlorthalidone which drops K+ anyways
When K+ went dangerously low (heart muscle contractility) caused heart to stop contracting
As part of the CMP, the glucose level is one of the more ______ values that you will commonly use
It is a direct measurement of the quantity of _______
Glucose levels are a direct result of feedback mechanisms and are controlled by
important
glucose in serum
glucagon and insulin
insulin and is secreted when glucose levels go up (it decreases blood glucose)
glucagon is secreted when glucose levels are low (it increases blood glucose)
what secretes insulin?
cells in the Islet of Langerhans in the pancreas
does Serum glucose need to be measured when patient has been fasting?
Many factors can increase glucose levels
such as
no it can be measured fasting or non-fasting
Stress, pregnancy, glucose-containing IV fluids
Medications (↑ or ↓)
reasons for increased glucose
1) diabetes
2) acute stress response (-body needs energy (fight or flight) so it needs glucose
Running from a tiger– need glucose )
3) pancreatitis (because pancreas gets inflamed and releases more glucose)
4) corticosteroid therapy –so for diabetics this can be hard to take
normal fasting glucose
70-110
Patients who have hypothyroidism have impaired hormonal responses to_____ They also have impaired ability to produce adequate _________
low glucose levels and inadequately respond when glucose levels are low. (low growth hormone and cortisol response).
glucose/gluconeogenesis
Karen is a 15 year old girl who presents to your family practice office with her mother, Linda. Linda states that Karen has been experiencing frequent bouts of dizziness over the last 3 weeks which are worse in the morning, but can happen at any time during the day. Karen feels tired, clammy and sometimes close to passing out frequently with the dizzy spells. She has no other neurologic symptoms, takes no medications, has no significant family history of cardiac disease, and her physical exam is unremarkable except you notice that she is wearing baggy clothes and refused to be weighed in at your office. After you coax her to the scale, you record her height at 5’6” and weight as 90 lbs.
1) What electrolyte abnormality could be causing her symptoms?
2) What other test(s) might you order?
3) What might you recommend?
1) -K+, glucose
- could also be an eating disorder
- one of the things you see a lot: young women in teens that are not eating as well as they should and they come in and feel tired/dizzy/syncopy. Ask them if they ate anything before feeling this? If they didn’t eat breakfast sugar could be low
2) - nutritional marker= prealbumin serum protein test
- -quick measure of nutritional status
3) tracking what she eats, eating at least 3x a day—eat every few hours
BUN
The ______ is the main filtering structure of the kidney
Glomerular filtration rate=
glomerulus
number of milliliters of body fluid cleared by the kidneys per unit of time = mL/minute
BUN
Urea formation occurs primarily in the _______ as a result of :
liver
the catabolism of protein into amino acids → free ammonia is formed in process
Ammonia molecules then combine to form urea, which is filtered by the glomerulus
so when you think urea, think protein
BUN
Approximately 50% of urea is reabsorbed in renal tubule and rest is excreted in urine
BUN therefore reflects the metabolic functioning of the
liver and excretory function of the kidneys
tells us about both liver and fxn of kidneys
Is BUN is the best reflector of kidney fxn alone?
no –it also tells you about liver fxn.–it is not specific to just kidneys. it is affected by fxn of kidney
Increased BUN can be due to
1) High protein diets
2) GI bleed (Digested blood is a source of urea and also patient may have decreased perfusion to kidneys due to bleeding)
3)dehydration
(increased protein of some kind)
If pt comes in with suspected GI bleed what tests do you run/what do you look for?
1) CBC (looking at hGB and HCT)
2) CMP (looking at BUN because blood is a source of protein that you are ingesting during a bleed)
Decreased BUN can be due to
1) low protein diets
2) starvation
3) over-hydration
(low protein in some way)
Creatinine- Better test to determine ____
why?
decreased kidney fxn (than BUN)
why? –> Creatinine is not affected by the function of the liver, unlike BUN and therefore we use it much more accurately to estimate how the kidneys are working!
Creatinine is byproduct of
Creatinine is filtered by the
Creatinine is Secreted by the kidneys at a
catabolism of creatine phosphate (which is involved in the contraction of skeletal muscles)
–Creatine phosphate breaks down into cretatinine
glomerulus of the kidney
at a constant rate (not metabolized or reabsorbed)
Creatinine is another marker of ___ functioning and is used with the BUN to obtain information about
renal
functioning of kidneys and the glomerular filtration rate
creatinine is Excreted entirely by the ____ and not affected by:
by the kidneys and NOT AFFECTED BY LIVER FUNCTION
Generally, creatinine levels are constant in the absence of disease and with stable muscle mass and consistent dietary intake
Production is dependent on ____therefore children and weaker people tend to have lower creatinine.
muscle mass
Do increases in creatinine tend to occur earlier or later in renal disease
later because some of the creatinine secreted is secreted by the renal tubules (as much as 10-20%)
Once you start to see someone’s creatinine go up, they have probably had a renal disease for awhile
Let’s say you have PKD and you’re 18 and you just start forming cysts on kidneys, early on in this disease, your Creatinine is probably normal
Once you see a creatinine “bump” in a pt, they’ve had the disease for awhile
So high creatinine means kidneys are not functioning well
A doubling in serum creatinine generally reflects a ___% decrease in the glomerular filtration rate
So if creatinine goes from 1 to 2, the pt has had___% less filtering going on
50%
50%
what can increase serum creatinine ?
1) disorders of renal dysfxn
2) urinary tract obstruction (ex: kidney stone can cause you to not get rid of urine which damages kidney which will affect creatinine)
3) diabetic nephropathy
4) rhabdomyolysis
5) gigantism/acromegaly (pic of giant)
ex: tumor on right side blocking off right ureter
Another ex: men with prostate cancer
what causes a decrease in creatinine?
debilitation
decreased muscle mass
Where is Calcium more abundant, ECF or ICF?
and is involved in:
ECF (than ICF)
Muscle contraction
Cardiac function
Neural transmission
Clotting cascade
Calcium exists in body in three forms:
1) protein bound- mostly bound to albumin, (but also to alpha, beta 1&2, gamma globin)
2) complexed-
3) ionized- “free” - active form (most metabolically active
% of calcium in each form
1) protein bound 40%
2) complexed 12%
3) ionized 48%
How is the homeostasis of calcium regulated?
through 1 of 2 mechanisms
1) PTH secreted by parathyroid in response to decreased calcium (it tells kidneys: “reabsorb calcium!!–keep it in the system!!”
it brings calcium from bone to blood stream
2) calcitonin -secreted by thyroid in response to increased calcium. it says “tone it down! there’s too much calcium!!”–it pushes calcium from blood stream to bone, causing kidneys to increase secretin of Ca2+)
If patient has elevated calcium, this doesn’t give us enough info to come up with a diagnosis so we need to order other tests like:
1) Ionized calcium…this test is unaffected by albumin (protein) levels (whereas in just a calcium test, if albumin is off–it can falsely affect your calcium level so this is why we order an ionized calcium because its more honest)
2) PTH (paraythyroid hormone) because that’s where calcium is secreted
3) Check albumin level, especially in malnourished patients (included in CMP)
High Ca2+ 2 main reasons:
1) Increased parathyroid (hyperparathyroidism)
2) cancer/malignancy
malignancy = second most common cause of hypercalcemia!!!
Bone metastasis- calcium is release from bone
Cancer can produce a PTH-like substance
causes of Increased calcium
1) hyperparathyrodism
2) cancer/malignancy/tumor
3) Vitamin D intoxication
4) acromegaly
causes of decreased calcium
1) hypoparathyroidism
2) Vit D deficiency (Vitamin D promotes the absorption of calcium)
3) hypoalbuminemia
4) malabsorption
Bilirubin is formed from the breakdown of ______ and is a component of _____.
This occurs in the_____ (mostly) and ____ system
RBCs, bile
spleen, reticuloendothelial system
(this system is part of our immune system that is composed of phagocytic cells and exists in multiple tissues)
When RBCs are broken down, they form ____+____ molecules
heme + globin molecules
Heme is catabolized and forms ____, which then becomes _____
This form of bilirubin is known as unconjugated bilirubin
biliverdin, bilirubin
Unconjugated bilirubin goes to liver where it gets conjugated with _____ to become _______
glycuronide
conjugated bilirubin
Bilirubin is therefore used as a measure of
liver function.
In order to determine the cause of the elevated bilirubin, we need to measure: .
Therefore, total bilirubin =
direct and indirect bilirubin as part of the total bilirubin
direct + indirect
Direct vs. Indirect bilirubin
indirect= unconjugated Direct= conjugated
Depending on where the defect occurs in the bilirubin pathway, either ____ or ______ can result
1) indirect (unconjugated) hyperbilirubinemia 2) direct (conjugated) hyperbilirubinemia
For example, if the defect occurs prior to conjugation with glycuronide, then ____ results
unconjugated hyperbilirubinemia
If a CMP is drawn and bilirubin is high we need to figure out if it s conjugated or nonconjugated. what’s the problem:
the problem:
On CMP it just says total bilirubin it doesn’t break it down for you into direct/indirect
So if you have pt with high bilirubin level (after doing CMP)—now you want to break it down to figure out which type of bilirubin it is and where defect is happening to create an increased bilirubin
____ occurs when bilirubin levels are too high.
jaundice
Jaundice can occur when total serum bilirubin exceeds ______
2.5 mg/dL
whereas normal bilirubin is 0.3-1.9
In newborns, their liver may not have adequate levels of _____ therefore
conjugating enzymes
bilirubin remains unconjugated
Unconjugated bilirubin has ability to________
what can result?
pass through blood-brain barrier
and if levels of unconjugated bilirubin are too high ( (>15 mg/dL is critical!)) mental retardation and encephalopathy can result
Causes of indirect (unconjugated) hyperbilirubinemia
1) Hepatocellular dysfunction
-Hepatitis- dysfxn of liver/inflammatin of liver
-Cirrhosis
Neonatal hyperbilirubinemia
2) Any disease process that increases RBC destruction
-Transfusion reaction
-Sickle cell anemia
-Hemolytic anemia
3) Many medications
** Not conjugating because liver is not functioning the way it needs to (hepatocellular dysfxn)
Causes of direct (conjugated) hyperbilirubinemia
1) Gallstones
2) Obstruction of extrahepatic ducts by tumor or other cause
3) Liver metastases (obstruction)
Liver is fine, however you may have something (ex: tumor) that blocks the flow of bile to the intestines (ex: tumor of gall bladder/gall stones)
High conjugated bilirubin– flow of bile is obstructed
Indirect Unconjugated Bilirubin normally is what percent of total bilirubin
if >85%, the causes could be from
70-85%
liver injury, RBC hemolysis, medications
Conjugated(direct) Bilirubin is what percent of total bilirubin?
if direct bilirubin > 50% it is usually caused by
15-30% (normal <0.2)
obstructive cause
Steve Jobs was diagnosed with pancreatic cancer in 2004 and ultimately lost his battle with the disease in 2011. Let’s pretend that he visited you in the office for his annual physical in late 2003, complaining of weight loss, early satiety (feel full before you should normal feel full)—not satiated, back and hip pain and depression. During your exam, you noticed a yellow tone to his skin and eyes. What labs are most indicative of his condition?
a. Calcium = 8.4 mg/dL, TB = 1.0 mg/dL, IB = 0.8 mg/dL, DB = 0.2 mg/dL b. Calcium = 9.0 mg/dL, TB = 2.1 mg/dL, IB = 1.7 mg/dL, DB = 0.4 mg/dL c. Calcium = 11.1 mg/dL, TB = 2.2 mg/dL, IB = 1.0 mg/dL, DB= 1.2 mg/dL d. Calcium = 11.5 mg/dL, TB = 2.2 mg/dL, IB = 1.9 mg/dL, DB = 0.3 mg/dL
He has an obstructive process most likely.
Which of the following is an obstructive pattern?
Pay attention to his calcium as well
Answer is C, as direct bilirubin is 50% or more
Normal level for calcium= 8-10
Calcium may be high because of possible metastasis to bone
Narrow the answers down to C &D
Then we look at TD, they are both the same so look at IB and DB and see that we want the one with high DB because if he has a big tumor in pancreas, we’d see a lot of direct bilirubin
Serum protein reflects the
synthesis and maintenance of the total amount of protein in the circulation.
The main components of the serum proteins are:
Almost all of the proteins are synthesized in the ______ therefore,
Albumin: most abundant ≈ 60 %
Globulins: composed of α1, α2, β, and γ globulins
liver failure can impair protein synthesis, but this is usually a later finding.
______ can cause a decrease in serum proteins.
Malnutrition
In healthy kidney tissue, most filtered protein is ______ by the renal tubules.
However, In renal disease, the glomerulus becomes less able to filter proteins and overwhelms the ability of the renal tubules to reabsorb protein → which leads to a _______
Therefore, patients with low serum protein should have a _____ to check for protein in the urine
reabsorbed
loss of protein in urine.
urinalysis
Causes of Hyperproteinemia
1) dehydration (less water= increased concentration of proteins –kind of false increase)
2) malignancy (overproduction of immunoglobulins)
3) infection (overproduction of immunoglobulins)
Causes of hypoproteinemia
1) hepatic failure/disease
2) malnutrition states
3) malabsorption states
3) renal failure/disease
_____ is the most abundant of the proteins found in serum
It Represents approximately ____ of serum proteins
albumin
60%
Albumin is synthesized within the_____
liver
Functions of albumin:
1) Important regulator of osmotic balance between intravascular and interstitial spaces…albumin “pulls’ water into circulatory system
2) Act as transporter for drugs, bilirubin, calcium, thyroid hormones and other hormones or enzymes
Half life of albumin? Good/bad indicator of disease/nutrition status?
Has relatively long half-life of 12-18 days, so not always good indicator of disease
The long half-life of albumin makes it a poor indicator of nutrition status (prealbumin better)
It also is not the greatest indicator of liver disease either, and may not manifest until disease severe or later stages of disease
Diseases that cause damage to the kidneys, especially the glomerulus, impairs the kidney’s ability to reabsorb albumin, leading to
increased albumin in the urine
What causes hyperalbuminemia?
dehydration (higher concentration of albumin in relation to fluid)
Causes of Hypoalbuminemia?
1) malnutrition
2) pregnancy
3) hepatic disease/failure
4) renal damage/kidneys “spill” protein into urine lowering amount circulating
Liver enzyme tests/Liver function tests include;
Includes Alkaline Phosphatase (ALP), Aspartate Aminotransferase (AST), Alanine Aminotransferase (ALT)
(3 primary enzymes found in the liver that are markers of how our liver is doing)
Liver function tests abnormalities can be caused by:
Injury to hepatocytes from alcohol
Medications or toxicity
Fatty deposits in the liver
Viruses, such as hepatitis
Alkaline phosphatase (ALP)
specific? good marker?
What is it?
Why is it called alk phos?
not very specific, good marker but not the best
an enzyme that is widely distributed throughout the body and functions in growth and development of bones, teeth and many other tissues → essential for bone mineralization
since it functions better at higher pH levels
Alk phos is most important in detection of
bone and liver disorders
where is alk phos found in highest concentrations?
Liver
Biliary Tract
Bone
ALP liver disorders
1) ALP is present in _____ cells of the liver and biliary tract and is secreted into _____ which makes it a good marker for
2) liver disorders in which ALP is found to be high/increased
3) liver disorders in which ALP is found to be decreased
1) Kupffer, bile, for liver abnormalities
2) Increased in:
- Cirrhosis of the Liver
- Obstruction of the biliary tract
- Liver tumors
- Drugs that are toxic to liver
3) Decreased in malnutrition states
Alkaline phosphatase
Bony disorders
Because ALP is essential to _______, it is elevated in any condition (normal or pathologic) of
so Elevated in:
new bone growth
bone formation
increased in:
Cancers that metastasize to the bone
Primary cancer of the bone
Post-fracture
Hyperparathyroidism will increase alk phos
Growing children!
(Elevated in any situation of abnormal/new bone growth/formation)
AST=
what is it, and what is it used for?
enzyme found in?
Aspartate Aminotransferase
This is another liver enzyme that can be used in the evaluation of the patient’s liver status.
AST is an enzyme that is found in highly metabolic tissue within the body, such as heart, liver, skeletal muscle, but can be found in other tissues as well.
If damage occurs to any of these tissues, ______is released into the circulation and its level ______.
AST
increases
Cell inflammation, injury and death = increased / Any disease that causes cellular injury to the liver will usually result in an elevation in the
AST
AST levels can rise remarkably high, up to ___x their normal value.
AST elevated in: (what causes AST to go up)
20
1) Liver disease, such as hepatitis (virus or caused by toxin/drug)
2) Tumors involving the liver
3) Infectious mononucleosis
ALT=alanine aminotransferase
what is it/what is it used for?
In the jaundiced patient, elevation of the ALT points to the
ALT is found primarily in the ____, but can be found in smaller amounts in other tissue (heart, skeletal muscle)
This is another test used to identify liver disease.
liver as the source instead of RBC hemolysis.
liver
If liver damage occurs, ___ is released into circulation.
ALT
ALT is a test that is more specific to the ____
so if ALT is increased, think
liver
LIVER ABNORMALITY!
What are some issues that causes ALT to increase?
Hepatitis- major increase
Hepatotoxic drugs- moderate increase
Cirrhosis- moderate increase
Normal for both AST and ALT hovers around
**look for triples of this—that’s when you will have significant findings (sometimes even 2x elevation isn’t significant)
think:
30-40
“Bad Habits” first: Obesity, Alcohol
Toxicity: medication (Tylenol, for example)
Illness or injury to liver
AST:ALT ratio
when ratio >1 it means
when ratio < 1 it means
Ratio > 1 in:
alcoholic cirrhosis- but frequently > 2 “don’t make an ast out of yourself when you are drunk”
metastatic tumor of the liver.
Ratio < 1 in: (usually viruses)
Viral hepatitis
Mononucleosis
scaled down version of CMP=
and includes
does not include:
BMP
Includes:
4 to 5 electrolytes: Sodium, Potassium, Calcium, Carbon Dioxide, Chloride
2 tests of kidney function: BUN and Creatinine
1 test of Glucose
does not include;
liver fan tests
When would you order a BMP?
If you only need to know the renal status of your patient and are not concerned over their liver, you can just order a BMP (circumstances vary)
Labs outside of the BMP/CMP:
BUN: creatinine ratio
when do you need to calculate/when you do not?
If both the BUN and creatinine are normal, not necessary to calculate ratio
If 1 or both are up, then you have to calculate the ratio
Azotemia refers to
3 types
increase in nitrogen containing compounds in the blood
1) prerenal
2) intra renal
3) post renal
Pre-renal azotemia:
results from abnormalities in systemic circulation that decrease blood flow to the kidney
** problem is not with the kidneys–it is with getting blood TO the kidneys
Anything that happens in the circulation prior to the kidneys (decreasing blood flow to kidneys) (starving the kidney of blood)
Ex: stenotic vessels, embolism, sepsis, dehydration (not enough blood volume to kidneys), hemorrhage (losing blood so not enough blood flow to kidneys)
Intra-renal azotemia results from
abnormalities within the kidneys themselves
PKD, uncontrolled HTN,
Post-renal azotemia: results from
obstruction of collecting system of kidneys (outflow from kidneys is not working)
ex: Kidney stones, tumor that can block off ureter/renal calyces
Someone with impaired renal fxn (kidney issues or severe dehydration) –N goes up and creatinine can go up
therefore Azotemia happens when you have
renal disease or something stressing kidneys out
If we check a CMP on an old lady that has been laying on the floor for 2 days until someone found her (weak/tired, etc)
Get a CMP, if you see an abnormality in BUN or creatinine,
calculate ratio
By knowing what the BUN:creatinine ratio is, we can start guessing what’s wrong with her
Normal BUN/Creatinine Ratio:
10:1 to 20:1
If BUN:Cr ration is >orequalto20:1
causes
the problem is pre-perfusion/pre-renal issue
causes: volume depletion of any cause sepsis hypotension CHF
if BUN:Cr ratio is
the problem is inside the kidney/intra-renal
causes:
any disease affecting the renal parenchyma such as glomerulonephritis, PKD, etc
When looking at BUN: Cr ratio when dealing with post-renal issues what are the usual ratios and what does this look like?
why?
Early ratio: >orequalto 20:1
late ratio:
Causes of Post-Renal BUN:Cr issues
Urinary Tract obstruction
nephrolithiasis
metastatic disease
GGT Test
in CMP?
Infants have ____ x normal range
Enzyme that is present in many tissues, including kidneys, pancreas, liver, spleen, heart, brain and seminal vesicles EXCEPT IT IS NOT PRESENT IN:
IMPORTANCE:
nope
6-7x
BONE
importance
Alk phos determines if you have a problem with either bone or liver–so if you test high for Alk Phos, you don’t know which one it is, bone issue or liver issue?
If you see an elevated Alk Phos you can order a GGT test to differentiate between liver and kidney disease
Which do you order first? GGT or Alk Phos?
specific?
You first order Alk Phos, then if elevated you order GGT to rule out bone
(because if GGT is high, that means it has to be the liver that’s the issue)
Not absolutely specific, but can be helpful to move away from bony diagnosis with ↑Alk phos
Liver disease can increase GGT (things from liver that can incerase GGT)
Hepatitis Cirrhosis Alcoholic liver disease Liver cancer/ metastasis Multiple other causes as well, including medications, pancreatitis, prostate and breast cancer, smoking tobacco use, race (↑AAs)
