uranlysis

554 terms by shumaila 

Ready to study?
Start with Flashcards

Create a new folder

Advertisement Upgrade to remove ads

the urine which is found in the calyx of the kidney, empties into which structure of the kidney?

Renal pelvis

solute dissolved in solvent will

decrease vapor pressure

ADH regulates the final urine concentration by controlling.

tubular permeability

the largest source of error in creatine test is

improperly timed urine specimens.

glucose will appear in the urine when the

renal threshold for glucose is exceeded

substances that may interfere with measurements of urine and serum osmolarity include all of the following except:

sodium

which statement regarding the normal salt and water handling by the nephron is correct?

The ascending loop of henle

which hormone controls reabsorption of water in the distal tubules?

Ant-duretic hormone (ADH)

when the body is well hydrated:

ADH production is decreased and urine volume is increased

Renin is secreted by nephron is response

low systemic blood pressure

select the clearance test that can be used to measure glomerular function:

creatnine

which of the following mechanisms do not control the acid base balance in the body?

chloride ion

which of the following is not involved with the bicarbonate ions

regulates calcium tubular secretion

the function of the peritubular capillaries is

reabsorption and secretion

the jeffe reaction is used today to measure which of the following compounds?

creatinine

water reabsorption (without stimulation from hormones) occurs in what parts of the nephron?

both proximal convoluted tubules and distal convoluted tubules

filtration of large protein is prevented in the glomerulus by:

capillary pores

which of the following is not considered a cause of renal azotemia?

hemorrhage

calcualte the creatine clearance rate using the following date: serum creatine = 2.4mg/dl
urine creatinine = 105mg/dl urine volume = 1.4L/day surface area = 1.80m^2

41 ml/min

which tubules in impermeable to water?

Ascending loop of henle

the end product of purine metabolism

uric acid

which of the following is the end product of the protein metabolism and is synthesized in the liver from the ammonia and carbon dioxide?

urea

blood flow through the nephron in the following order ?

Afferent arteriole, glomerulus efferent arteriole, peritubular capillaries, vasa recta, peritubular capillaries

renal excretion is not involved in the elimination of:

normal by-products of fat metabolism

part of the nephron that contain the glomerulus is called?

bowman's capsule

what is the endocrine (hormone) gland attached to the kidney?

adrenal

the primary chemical affected by the renin angiotesin-aldosterone system is:

sodium

the small renal artery branch in the nephron, through the blood flows away from the glomerulas is known as?

Efferent arteriole

to provide an accurate measure of the renal blood flow, a test substance should be completely:

cleared on each contact with functional renal tissue

select the clearance test that can be used to measure renal blood flow

p-aminohippuric acid (PAH)

which of the following statement are correct about creatinine clearance is correct?

creatinine clearance is mainly determined by renal tubular function

in the nephron, where does the reabsorption of glucose takes place ?

proximal convoluted tubule

increased nitrogenous waste products in the blood is known as :

Azotemia

of the ultrafiltrate passing through the glomerulus what percentage is ultimately excreted as urine ?

1%

the hormone aldosterone is responsible for

sodium retention

diabetics frequently drink excessive amounts of fluids to quench their thirst. this symptom is called:

polydypsia

the specific gravity,but not to the osmolality?

protein

an unidentified fluid is received in the laboratory with a request to determine if the fluid is urine or another bod fluid. Using routine laboratory tests, what test would determine that the fluid is most probably urine?

urea and creatinine

if ammonia is not produced by the distal convoluted tubule, the urine PH will be :

basic

which of the following is the closest to the reference range for total urine output in a single day(ml/day)

500 to 1800

what is the differance btw osmolality and osmolarity?

osmolality is the concentration of an osmotic solution especially when measured in osmols or milliosmoles per 1000 grams of solvent. osmolarity is the concentration of an osmotic solution especially when measured in osmols or milliosmole per liters of solvent.

what is the formula for the manual calculations of osmolality?

1.86(NA)+(glu/19) + (BUN/2.8) = osmolality

name 3 substances that are elevated in the blood with renal disease?

BUN, Creatinine, uric acid

what is urea

the end product of protein matabolism. it is synthesized in the liver from ammonia and carbon dioxide.

why should tubes containing fluoride or citrate not be used when collecting blood for urea if analysis will be by the urease method?

flouride and citrate inhibit urease.

what is the formula for converting BUN t urea?

urea= BUN 60/28 or BUN 2.14

where is 98%of the bodies creatine located

in muscles

what is creatinine?

the anhydride of creatine . Creatinine is formed from creatine by splitting out water.

what reaction is used to measure creatinine?

the jeffe reaction using alkaline picrate. It is non-specific, but still clinically useful, method.

what is the reference range for creatinine?

.5-1.2 Mg/dl (44-196mmol/L)

what is the significance of BUN: creatinine ratio?

It helps determine the cause of an increased BUN. The normal ratio is approximately 10:1 to 20:1.
higher ratios are due to non-renal causes, such as high protein diet, increased rate of protein catabolism, or decreased renal blood flow.
with these conditions the BUN increases more than the creatinine.
with renal disease, the BUN and creatinine increases proportionally.

Calculate the BUN: creatinine ratio for a patient whose BUN is 45mg/dl and whose creatinine is 2.1 mg/dl

45/2.1 = 21.4

what is the estimated glomerular filtration rate (eGFR)?

A calculation value based on serum creatinine and the patient's age sex, and race. the national kidney disease education program encourages reporting eGFR along with serum creatinine because it is a more sensitive indicator of the kidney disease. At this time, the practice is not widely adopted.

what is uric acid?

the end product of purine metabolism. the purines are adenosine and guanine, components of nucleic acids.
uric acids is increased in gout, renal disease, and condition where there is high cellular turnover, such as leukemia.

what reagents is commonly used to measure uric acid

Uricase. the preservative sodium fluoride must not be used to collect the blood sample because it destroys uricase.

what may results from high levels of uric acid?

urate crystals may precipitation in joints and tissue.

why must the PH of urine for uric acid determination be adjusted 7.5-8?

to prevent precipitation of uric acid. uric acid precipitates at acid ph.

which of the following statements regarding urea is true?

urea is the major nitrogen-containing metabolite from the degradation of protein.

An increased serum level of which of the following analytes is most commonly associated with decrease GFR.

creatinine

which of the following test would best support the diagnosis of chronic renal failure?

increased BUN, increased creatinine

creatinine is a good substance to use for a clearance test because?

It's blood values are stable day to day

creatinine clearance is used to estimate?

Glomerular filtration rate

In gout, what analyte deposits in joints and other tissues?

Uric acid

what analyte is measured using the jeffe reaction?

creatinine

In the urea method, the enzymatic reaction of urease is inhibited when the blood for analysis is drawn in a tube containing which of the following anticoagulants?

sodium fluoride

A patient has the following values?
serum creatinine =2.0 mg/dl
urine creatinine =123mg/dl
24hour urine =1460mls
patient height=5ft 8in
patient weight=140lbs
calculate the creatinine clearance?

C=UV/P
123mg/dl*1460ml/24hr/60min/2.0mg/dl=62ml/min

the type of nephron responsible for renal concentration is the?

juxtaglomerular

the function of the pertitubular capillaries is?

reabsorption and secretion

blood flows through the nephron in the following order?

Afferant arteriole, pertitubular capillaries, vase recta, efferent arteriole.

filtration of protein is prevented in the glomerulus by:

capillary pores

renin is secreted by the nephron in response to:

low systemic blood pressure

the primary chemical affected by the renin angiotensin-aldosterone

sodium

secretion of renin is stimulated by?

macula dense cells

the hormone aldosterone is responsible for:

sodium retention

the fluid leaving the glomerulas has a specific gravity of :

1.010

All of the following are reabsorbed by active transport in the tubules except:

urea

which of the tubules is impermeable to water?

Ascending loop of henle

glucose will appear in the urine when the:

blood levels of glucose is 200 mg/dl
TM for glucose is reached
renal threshold for glucose is exceeded

the concentration mechanism takes place in the:

juxtaglomerular nephron

ADH regulates the final urine concentration by controlling

tubular permeability

when the body is dehydrated

ADH production is increased

bicarbonate ions filtered by the glomerulus are returned to the blood?

the proximal convoluted tubule
combined with hydrogen ions
by tubular secretion

If ammonia is not produced by the distal convoluted tubule, the urine PH will be:

basic

place the appropriate letter in front of the following clearance substances: A.exogenous
B. endogenous

exogenous=inulin
endogenous= creatinine
endogenous=cystatin C
exogenous=125^I-iothalmate

the largest source of error in creatinine clearance test is:

improperly timed urine specimens

given the following information, calculate the creatinine clearance
24 hour urine volume : 1000 ml; serum creatinine : 2.0 mg/dl; urine creatine 200 mg/dl

69ml/min

values for the creatinine clearance tests on children are corrected for :

body size

given the data serum creatinine: 1:1 mg/dl; age 50 years, and weight 72 kg the estimated creatinine clearance using the cockcroft-gault formula is :

82

variables that may be included in estimated creatinine clearance calculations include all of the following except:

urine creatinine

An advantage to using cystain C to monitor GFR is :

It does not require urine collection
it is not secreted by the tubules
it can be measured by immunoassay

solute dissolved in solvent will:

decrease vapor pressure

substances that may interfere with measurement of urine and serum osmolarity include all of the following except:

sodium

the normal serum osmolarity is :

275- 300 mosm

After controlled fluid intake, the urine to serum osmolarity ratio should be at least:

3:1

calculate the free water clearance from the following results: Urine volume in 6 hours: 720ml; urine osmolarity 225 mosm; plasma osmolarity :300 mosm

+0.5

to provide an accurate measure of renal blood flow, a test substance should be completely :

cleared on each content with functional renal tissue

given the following date calculate the effective renal plasma flow :
urine volume in 2 hours :240 ml;urine PAH: 150mg/dl; plasma PAH: 0.5 mg/dl

600ml/min

renal tubular acidosis can be caused by the:

inability to produce an acidic urine due to impaired production of ammonia

tests performed to detect renal tubular acidosis after administering an ammonium chloride load include all of the following except:

Arterial PH

A 44 year old man diagnosed with acute tubular necrosis has a blood level of 100 mg/dl. A 2+ urine glucose is also reported.
A. state the renal threshold for glucose.
B. what is the significance of the positive urine glucose and normal blood glucose?

A. 160 to 180 mg/dl
B. renal tubular reabsorption is impaired

A patient develops a sudden drop in blood pressure.
A. Diagram the reaction that takes place to ensure adequate blood pressure within the nephrons.
B. how do these reactions increase blood volume?
C. when blood pressure returns to normal, how does the kidney respond?

A. juxtaglomerular apparatus-> Macula densa > justaglomerular apparatus> Angiotensinogen > renin > angiotensin 1 > Angiotensin 2
B. vasodilation and constriction, increased sodium reabsorption, increased aldosterone and ADH Production.
C. production of renin deceases, and this reduces the actions of the renin-angiotensin -aldosterone system.

A physician would like to prescribe a nephrotoxic antibiotic for a 60 year old man weighing 80 kg. the patient has a serum creatinine level of 1.0mg/dl.
A. How can he physician determine whether it is safe to prescribe this medication before the patient leaves the office
B.can the medication be prescribed to this patient with a reasonable assurance of safety.
C. A creatinine clearance was also run on the patient with the following results: serum creatinine .9 mg/dl; urine creatinine ,190 mg/dl; 24 hour urine volume, 720 ml. should the patient continue to take the medication? justify your answer.

A. the physician can calculate the approximate creatinine clearance using the cockcroft-gault formula.
B. yes, the measured creatinine clearance is 80 ml/min a normal range for a male and female.
C. yes, the measured creatinine clearance is 86 ml/min normal for this patient.

A laboratory is obtaining erratic serum osmolarity results on a patient who is being monitored at 6 am, 12 pm, 6pm, and 12 am . osmolarities are not performed on the night shift; therefore , the midnight specimen is run at the same time as the 6 am specimen.
A. what two reasons could account for these discrepancies?
B. If the laboratory is using a freezing point osmometer, would these discrepancies still occur? why or why not?
C. if a friend was secretly bringing the patient a pint of whiskey every night , would this affect the results? explain your answer?

A.serum from the midnight specimen is not being separated from the clot and refrigerated in a timely manner.
B. yes, lactic acid effects both cryoscopic and vapor pressure osmolarity.
C. If the laboratory is using a cryoscopic osmometer, results will be effected by alcohol ingestion; vapor pressure results would not be affected and could be used as a comparison.

following overnight (6 pm to 8 am) fluid deprivation, the urine to serum osmolarity ratio in a patient who is exhibiting polyuria and polydipsia is 1:1 the ratio remains the same when a second specimen is tested at 10 am. vasopressin is then administered subcutaneously to the patient, and the fluid deprivation is continued until 2 pm, when another specimen is tested.
A. what disorder do these symptoms and initial laboratory results indicate?
B. if the urine to serum osmolarity ratio on the 2 pm specimen is 3:1, what is the underlying cause of the paient's disorder?
C. If the urine to serum osmolarity ratio on the 2 pm specimen remains 1:1, what is the underlying cause of the patient's disorder.

A. Diabetes insipidus
B. decreased production of ADH
C. lack of tubular response to ADH

The nephron is composed of how many parts?

5 basic parts

Define the term ultrafiltrate of plasma

ultrafiltrate of plasma is when the nephron forms a filtrate of protein free plasma. It occurs across the glomerular capilliaries passing through the three cellular layer which are the capillary wall membrane, the basement membrane, and the visceral epithelium of the bowmans capsule. which then results in a hydrostatic pressure within the capillary which pushes the water and solutes across the filtration membrane. (filtrate reflects the plasma except for large molecules and cells)

urea results form the breakdown of ?

Amino acids

the kidney is stimulated to produce a renin when.....

extracellular fluid decreases

when the body is dehydrated, the production of ADH is .........

increased

when sodium is filtered by the glomerulas with ____% being reabsorbed in the proximal tuble?

70%

which ion is freely filtered by the glomerulas and must be reabsorbed to maintain a proper PH?

bicarbonate ion

which of the following is not a main function of the kidneys?

regulation of hemoglobin

the descending loop of henely is _________ permeable to water.

freely

the ___________ is the final stage for concentrating or diluting the urine.

collecting duct

studies have shown that increase in _________ occur before an increase in creatinine in cases of acute renal failure.

cystain C

the serum osmolality reading of 289 mosmo/kg is considered .......

normal

in the______ method for determining creatinine concentration the resulting red orange complex known as __________ complex absorbs light in the 480 to 520 nm range.

jeffe, janovski

elevated levels of creatinine may be caused by __________

kidney infection
heart failure
enlarged prostate gland

blood urea nitrogen (BUN) results as a waste product from _______

protein metabolisms

post renal azotemia may result from _______

congestive heart failure

elevated levels of __________ may lead to a condition know as ________ which can lead to painful joints

uric acid and gout

acute glomerulonephritis sometimes occurs after infection of _________

group a streptococcus

massive protenuria (>3.5g/day ) is a hallmark for

nephrotic syndrome

A patient presents with protienuira, hematuria and casts. the patient serum has elevated levels of BUN, creatinine and phosporus; serum calcium is decrease. these symptoms are closely associated with....

Acute renal failure

the six main function of the kidney as follows?

urine formation
regulation of fluid and electrolyte to balance
excretion of waste products of protein metabolism
hormonal function
protein conservation

in the urine formation the nephron has functional units of the kidneys which contains 5 parts they are?

glomerulus, proximal convoluted tuble,loop of henley, distal convoluted tuble, collecting duct

in the glomerulus of the basement membrane why is it semi permeable

it filters everything except cells and large molecules.

the proximal tubule has both what?

functions of secretary and reabsorptive

the proximal secretes a variety of ?

organic acids and bases, as well as hydrogen, ammonium and drugs.

in the loop of henley the medulla interstitial fluid maintains a?

hyperosmotic environment

descending loop of henley is freely permeable to water B/C?

passive reabsorption of water in the osmotic gradient of the medulla

where is urine concentrated in the loop of henley?

bottom of the loop

what is it called when the descending loop of henley is relatively impermeable to water and actively reabsorbs chloride and passively reabsorbs sodium and urea this is called what?

diluting segment because of the loss of salt without water in the final urine.

the primary function of the convoluted tubule is to make?

fine adjustments to achieve acid base equilibrium and electrolyte balance.

what percents of the sodium, chloride and water has been reabsorbed of the urine filtrate?

95%

If the acid base equilibrium and electrolyte balance is responsive to aldosterone that is secreted by the adrenal cortex. what does this result in?

it results in a reabsorption of sodium and secretion of potassium and hydrogen of the distal convoluted tubule.

hydrogen secretion is involved in what regeneration of the distal convoluted tubule.

bicarbonate regeneration (acid base balance) and ammonium secretion.

what is the final site for concentrating urine or diluting the urine.

collecting duct.

the collecting duct is also under the influance of ?

the collecting duct is under the influence of aldosterone (sodium reabsorption) and another hormone called ADH (antidiuretic hormone)

ADH is produced by? and stimulated by in the collecting duct?

ADH is produced by the lower pituitary gland and is stimulated by increase blood osmolality or decrease blood volume.

In the presence of ADH water is ____________ in the collecting duct. In the absence of ADH water is?

In it's presence water is permeable in the collecting duct (reabsorbs) , and in its absence , water is impermeable (excreted)

steps in how the final urine flows.

the urine flows from the collecting duct (cortex) of the nephron to larger connecting ducts (medulla) which coalesce to form a central duct in the renal pyramids. these then drain through the papilla into the renal pelvis and finally into the ureters.

( collecting duct > medulla >central duct in the renal pyramids >papillla >renal pelvis >ureters

what are the cells in the afferent and efferent arterioles that produces renin? (IN the collecting duct)

Juxtaglomerular cells

what is renin?

it is a peptide hormone that initiates a hormonal cascade that ultimately produces Angiogenesis 2 .

define Angiogenesis 2

it stimulates the adrenal cortex to produce aldosterone

which function out of the 6 function is this?
the human kidney has the ability to produce highly concentrated or dilute urine, ranging from 50 mOsm/kg to 1200 mOsm/kg.

regulation of fluid and electrolyte balance.

with dehydration or low water reserves extremely concentrated urine is produced to?

converse(reversed) body water

when the body is over-hydrated, extremely dilute urine is produced to eliminate?

excess body water

what does increased blood osmolality or low blood volume initiate?

1. secretion of AHD which increases renal tubular reabsorption of water (collecting Duct)
2. thirst, which increases fluid intake and is under the regulation of the thirst center in the hypothalamus.

See More

Please allow access to your computer’s microphone to use Voice Recording.

Having trouble? Click here for help.

We can’t access your microphone!

Click the icon above to update your browser permissions above and try again

Example:

Reload the page to try again!

Reload

Press Cmd-0 to reset your zoom

Press Ctrl-0 to reset your zoom

It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.

Please upgrade Flash or install Chrome
to use Voice Recording.

For more help, see our troubleshooting page.

Your microphone is muted

For help fixing this issue, see this FAQ.

Star this term

You can study starred terms together

NEW! Voice Recording

Create Set