Exam 3 Flashcards
(149 cards)
1
Q
What solutes are used to monitor renal function
A
urea and creatinine
2
Q
What measurements are used to asses quantity of solutes in urine
A
SG and osmo
3
Q
What are the 3 most abundant solutes in urine
A
urea
chloride
sodium
4
Q
What are the 3 least abundant solutes in urine
A
Uric acid
glucose
albumin
5
Q
What is osmolality
A
the number of particles in a solution
6
Q
Urea ____ dissociate in solution
NaCl ___ dissociates in solution
Which one has the highest osmolality
A
urea does not
NaCl does
NaCl has twice the osmo than urea
7
Q
IF the osmo of the initial filtrate = the osmo of the plasma
A
isosmotic
8
Q
Ultrafiltrate in Bowman;s space has ___ solute composition as plasma, but lacks ___
A
the same
lacks albumin
9
Q
What is the osmolality of the ultrafiltrate in Bowman’s space and plasma
A
300 mOsm
10
Q
What determines the final osmo of urine
A
the distal tubules and collecting ducts
11
Q
If ADH is present, does osmo increase or decrease as water absorbed in the collecting ducts
A
increases
12
Q
What is the max osmo possible
What is the normal osmo
A
max- 1400
normal-275-900
13
Q
Where can urine be hypertonic
A
medullary interstitium
14
Q
What produces hypertonic urine
A
posterior pituitary releases ADH
15
Q
what is the normal urine to serum osmo ratio
A
1-3
16
Q
Urine osmo should be ___x the serum osmo
A
1 to 3 times
17
Q
What is polydipsia
A
intense thirst, brought on by diabetes
18
Q
ADH makes you pee ___ water, making urine ___ concentrated
A
less water
more concentrated
19
Q
What is specific gravity
A
ratio of mass of solutes to pure water
20
Q
What is the normal SG range
A
1.002 to 1.035
21
Q
How do large molecules affect the SG value
A
dramatically increases SG compared to small solutes
22
Q
What are some large molecules that can be present in urine
A
Glucose
23
Q
What can cause an extremely high SG
A
> 1.050
X ray dye or mannitol
DOES NOT AFFECT OSMO
24
Q
What is the difference between osmo and SG
A
osmo-# of solutes
SG- mass of solutes
both measurements of concentration of urine
25
What is the normal daily urine excretion
500-1800
26
How much urine do the kidneys secrete when a person is dehydrated? and excessively hydrated?
dehydrated- small volume
excessively hydrated-large volume
27
What are the 2 main causes of polyuria
water diuresis- low osmo >200, inadequate ADH secretion or inactive action of ADH
solute diuresis- > 300 , usually imbalance of glucose, urea, sodium
28
what is oliguria? and anuria
oliguria- decreased urine- <400
anuria- no urine excretion
29
Which is preferred? Osmo or Sg and why
Osmo- because its more accurate
except for HMW solutes
30
How is tubular concentration affected in chronic renal disease? What happens to SG and osmo?
causes inability to rebsorb and secrete solutes from ultrafiltrate
SG and osmo- same as initial ultrafiltrate in Bowman's space
causes polyuria and nocturia
31
What is a fluid deprivation test and what is its purpose
Deprive patient of fluids from 6pm to 8am
ADH administered at the end
To find causes of water diuresis, could be defective ADH or lack of a response to ADH
32
Match neurogenic or nephrogenic
-lack of ADH response
-defective ADH
neurogenic- defective ADH
nephrogenic- lack of ADH response
33
What does a positive response and a negative response to fluid deprivation test
positive- urine osmo high- this means the kidneys responded to the ADH, therefore the patient must not be producing enough ADH-neurogenic problem
negative- urine osmo low- this means the renal receptors for ADH must not be working, because there is no response when ADH is present- nephrogenic problem
34
What is osmolar clearance
What is free clearance
osmolar clearance- ratio of urine osmo to serum x urine volume
Free water clearance- additional water that exceeds bodily needs and is eliminated in the urine
35
When the total urine equal the osmolar clearance volume
urine is _____ with plasma
Ch20 is ___
urine osmo = serum osmo
isosmotic
CH2O is zero
36
When urine is dilute because of water diuresis
urine is _____
The CH2O is ____
urine is hypo-osmotic or hypotonic
Uosmo
37
When urine is concentrated due to dehydration
urine is ___
CH2O ___
urine is hyperosmotic
CH2O is negative
38
How does dehydration affect
Uosm
Sosm
V
Cosm
CH2O
Uosm- increases
Sosm- increases
V-decreases
Cosm- decreases
CH2O- decreases
39
Practice the formula for Osmolar clearance
Cosm = (Uosm/Sosm) x V
40
What units should creatinine clearance be in what other formulas have the same unit
mL per minute not hr
RBF
41
Practice the formula for renal clearance
C= U x V/ P
U=urine
P=plasma
42
What is GFR in general?
What is the measured GFR? and estimated?
glomerular filtration rate- the rate of plasma cleared by the glomeruli
measured- using clearance test
estimated- using equation or biomarkers
43
What is the normal reference range for GFR
What do the abnormal results mean
>60 normal
<60 kidney disease
< 15 kidney failure
44
What is inulin
not absorbed by GI tract, administered before and throughout the inulin clearance test
passes through glomerular filtration and is NOT reabsorbed
ideal substance for determining GFR, not practical for routine/ periodic GFR
45
What is the most frequently used test for routine assessment of GFR
creatinine clearance
46
How can more accurate creatinine testing be obtained
using 24 hr urine collection
47
What is creatinine
a biproduct of muscle metabolism
48
Is creatinine varied or constant in its production
should be steady, constant plasma and urine excretion rate
49
What influences creatinine production
muscle mass, can vary depending on age, gender and physical activity
50
What is the average persons body surface area, why is it used in calculations for creatinine clearance
1.73m^2
accounts for the differences in muscle mass in individuals
51
Practice the creatinine clearance calculation
C= ((U x V)/ P ) x (1.73/SA)
P= plasma
U=urine
SA= patient surface area
52
What can normal creatinine clearance be?
between 30 and 130
53
What special consideration must be kept in mind for creatinine clearance testing
-24 hr urine- to account for diurnal variation in GFR
-must be stored correctly to avoid bacteria proliferation which can breakdown creatinine
-must have the correct urine volume
54
When do we use estimated GFR
when serum creatinine test is done on patients older than 18
55
What is the reference range for creatinine clearance
88-137
56
What other markers can we use to determine GFR other than creatinine, name the advantages and disadvantages, are the absorbed?
Cystatin C- the same in every age group, muscle mass and gender, does not return to blood circulation, expensive
Beta 2 microglobulin- is reabsorbed completely, concentration is constant
57
As blood cystatin C levels increase, GFR ____
decreases
58
As tubular capacity to reabsorbe decreases, B2 microglobulin ____
increases in concentration in the urine
59
what is the purpose of screening for microalbuminuria
to monitor patients with diabetes, can detect early nephropathy
60
What can lead to proteinuria and what is the most important reason we look for it
changes in glomerular filtration barrier-> increased glomerular permeability-> proteinuria
to detect hyperglycemia- caused by too much albumin
61
What is RBF, practice the formula for it
Renal blood flow
Renal plasma flow
RBF= RPF / (1-HCT)
practice real problem on pg 63 ch 4
62
What is the most common test used to measure RPF
P-aminohippurate clearance test
63
What is the oral ammonium chloride test and what is it for
taken and breaks down into urea and HCL
kidneys excrete more titratable acid and ammonium salt, causing acidic urine
if acidic urine is not there- renal tubular acidosis-alkaline urine
64
What are the 4 types of renal diseases
glomerular
tubular
interstitial
vascular
65
What are the diseases that damage glomeruli
glomerulonephritides
glomerulonephritis
66
What is the primary mode of glomerular injury in glomerular disease
immune mediated response
antigen antibody complexes that get trapped in glomeruli
chemical and toxic substances produced by immune response
67
What are features that characterize nephritic syndrome
and nephrotic syndrome?
nephritic: hematuria, proteinuria, oliguria, azotemia, edema, hypertension (i, inflammation of gomeruli)
nephrotic: heavy proteinuria, hypoproteinemia, hyperlipidemia, lipiduria, generalized edema
68
What is azotemia
buildup of nitrogenous substances
69
What is the most common cause of nephritic syndrome
berger's disease
70
Gomerulonephritis that happens after strep throat in children
AGN, RPGN, MGN, MCD, FSGS, MPGN, IgA nephropathy, chronic glomerulonephritis
AGN
71
Glomerulonephritis that causes crescent shape in proximal tubule
FSGS, MCD , MGN, IgA nephropathy , RPGN, MPGN, ,chronic glomerulonephritis, AGN
RPGN
72
Glomerulonephritis that causes loss of foot processes, major cause of nephritic syndrome in adults
AGN, RPGN, MGN, MCD, FSGS, MPGN, IgA nephropathy, chronic glomerulonephritis
MGN
73
Which glomerulonephritis is characterized by complement activation causing glomerular damage, what specific part of the complement system is activated
AGN, RPGN, MGN, MCD, FSGS, MPGN, IgA nephropathy, chronic glomerulonephritis
MGN,
MAC us activated
74
Glomerular nephritis that is caused by dysfunstional T cells, most common cause of nephritic syndrome in children
AGN, RPGN, MGN, MCD, FSGS, MPGN, IgA nephropathy, chronic glomerulonephritis
MCD
75
Glomerulosclerosis that is characterized by the sclerosis of glomeruli, damage to podocytes
AGN, RPGN, MGN, MCD, FSGS, MPGN, IgA nephropathy, chronic glomerulonephritis
FSGS
76
Which gomerular disease can recur after renal translant
FSGS
77
What glomerulonephritis is mostly immune mediated, by leukocyte proliferation and thickening of glomerular basement membrane
AGN, RPGN, MGN, MCD, FSGS, MPGN, IgA nephropathy, chronic glomerulonephritis
MPGN
78
Which glomerular disease if one of the most prevalent types of glomerulonephritides in the world, activates alternative complement pathway
AGN, RPGN, MGN, MCD, FSGS, MPGN, IgA nephropathy, chronic glomerulonephritis
IgA Nepropathy
79
Which glomerulonephritis is characterized by renal failure
chronic glomerulonephritis
80
What are the systemic glomerular diseases, briefly describe them
systemic lupus erythematosus- SLE-immune system activates complement
amyloidosis- deposition of amyloid a pathologic protein, destroys glomeruli
Diabetes- ends in kidney disease, high blood sugar leads to blood flow issues
81
What is ATN, what are the 2 types
acute tubular necrosis
destruction of renal tubular epithelial cells
Ischemic- low bp (hypotension) , less filtering
Toxic ATN- exposure to toxic agents
82
50% of all ATN cases result from _____
surgical procedures
83
What are the effects of Ischemic ATN, and toxic?
Ischemic- sepsis, shock, trauma
Toxic- nephrotoxins
84
What do both ATN types show
casts
85
What disorders do not affect glomerular function, for the GFR looks normal
tubular dysfunction
86
What is Fanconi's syndrome
condition where proximal tubules have lost their function
AAs, glucose, water, phosphorous, potassium, calcium not reabsorbed, show up in pee
87
What is cystinosis and cystinuria
excretion of cystine, due to renal tubular dysfunction,
88
What is renal glucosuria
excretion of glucose in urine, normal blood glucose levels
decreased Tm for glucose
89
What is renal phosphaturia
hereditary, inability of distal tubules to reabsorb inorganic phosphorous
90
What is RTA
renal tubular acidosis- tubules are not secreting hydrogen ions correctly, causes alkalline urine when it should be acidic
91
What is tubulointerstitial disease
affect renal interstitium caused by infection, toxins, metabolic, vascular, irradiation, neoplasms, transplant rejection
92
What parts of the urinary system do lower UTIs affect
urethra, bladder, both
93
What is an infection of the bladder called
urethritis
94
What parts of the urinary tract are affected in an upper UTI
renal pelvis only can include interstitium
95
What is pyelitis
infection of the renal pelvis
96
What is pyelonephritis
infection of renal pelvis and interstitium
97
What is the pathogen that most commonly causes UTIs
E. coli
98
What differentiates lower from upper UTIs
no pathological casts- lower UTI
casts- upper UTI
99
What is acute pyelonephritis
bacterial infection in renal tubules, interstitium and renal pelvis
most common-bacteria move up from lower urinary tract
rare- bacteria get in from blood
100
What is chronic pyelonephritis
persistent inflammation of renal tissue with permanent scarring in renal calyces and pelvis
101
What is the most common cause of acute allograft rejection of a transplanted kidney
AIN acute interstitial nephritis
102
What are increased eosinophils characteristic of
acute interstitial nephritis AIN
103
What kind of UTI is acute pyelonephritis?
upper UTI
104
What characterizes ARF
decrease in GFR, azotemia, oliguria
105
What makes it so that ARF has a high mortality rate
oliguria can lead to anuria, causes necrosis and death
106
What are the 3 mechanisms that lead to ARF
prerenal-decrease in renal blood flow
renal- renal damage
postrenal- obstruction of urine flow
107
What is CRF characterized by
progressive loss of renal function, irreversible and intrinsic renal disease
108
What causes CRF
glomerulonephropathies mostly
109
What can CRF eventually progress to
end stage renal disease- dialysis or renal transplant to live
110
75% of renal calculi contain ____
calcium
111
What factors influence renal calculus
supersaturation of chemical salts in urine
optimal urinary pH
urinary stasis
nucleation or initial crystal formation
112
What are the pH changed with a patient that has calculi
isohyduria
113
What are staghorn stones
stones in the renal pelvis become large and extend into two or more calyces, always associated with upper UTI
114
What is the pain that is produced from kidney stones called
renal colic
115
What are the 3 types of aminoacidurias
overflow- increase in plasma levels of AAs
no threshold- increased AAs in blood and urine
renal-AAs not reabsorbed due to tubular defect
116
What is cystinosis
inherited lysosomal storage disease that results from intracellular deposition of cystine, causes cellular damage and function faulure
117
What type of cystinosis
most common and severe
causes Fanconi's syndrome
causes growth retardaton, polyuria....
Nephropathic cystinosis
118
What type of cystinosis
slower rate of progression, can cause kidney failure by early thirties
intermediate cystinosis
119
What type of cystinosis
manifests only in ocular impairment
ocular cystinosis
120
What is cystinuria
cystine crystals in urine,
121
What changes can you make in your diet to avoid cystinuria
change diet to alkalinize urine, hydration especially at night
122
What characterizes MSUD
maple syrup urine disease
Leu, Ile, Val in blood CSF and urine
123
What causes maple syrup odor in MSUD
ketoacids
124
What is PKU
phenylketouria (PKU) - excretion of phenylpyuvic acid and its metabolites
125
What is the classic cause of PKU
phenylalanine hydroxylase enzyme is deficient or defective
126
What disease is characterized by a mousy musty odor, patients with lighter skin, hair and eyes.
PKU
127
What is Alkaptonuria
large amounts of homogentisic acid HGA
decreased levels of homogentistic acid oxidase
128
What does HGA do
binds to collagen in connective tissues, causes abnormal dark blue or black tissue pigmentation
129
What disease is characterized with causing pigmented ears
Alkaptonuria
130
What is tyrosinuria
increased tyrosine in urine, rarely causes tyrosine crystals
131
What is melanuria
increased urinary excretion of melanin, black urine in extreme cases
132
ochronosis
pigmented ears, alkaptonuria
133
mousy smelling urine
PKU
134
Ketoacids in urine
Maple syrup urine disease
135
Hexagonal crystals in urine
cystineuria
136
homogentistic acid in urine
Alkaptenuria
137
What characterizes diabetes meillitus
hyperglycemia and glucosuria
138
Type 1 and type 2 diabetes
1- insulin dependant, juvenille
2- non insulin dependant, adult onset
139
What test results can we expect from a patient with diabetes mellitus
dilute urine
high SG
ketonuria
140
What are the classic symptoms of diabetes type 1
polyuria and polydipsia
141
What are the symptoms of type 2 diabetes
hyperglycemia, no insulin needed
142
What is galactosemia with galactosuria and its types
carbohydrate disorder
type 1- most common, GALT
type 2- deficiency of GALK, cataracts
type 3- deficiency of GALE
143
Neurogenic vs nephrogenic diabetes insipidus
neurogenic- release of ADH is reduced
nephrogenic- defective renal tubular response to ADH
144
What is characterized with bland tasting urine
diabetes insipidus
145
What test results can be expected from diabetes insipidus
polyuria, polydipsia
low SG
146
What are porphyrias
porphyrins- side products of heme production
porphyrias- disorder where there is an accumulation of porphyrins, or precursos of porphyrins
147
What lab findings can we expect from porphyrias
dark or purple urine if exposed to light
prophyrins in urine, blood and feces
148
What are the 2 types of porphyrias
hepatic or erythropoietic
149
What are the symptoms of porphyrias
neurologic- due to neurotoxic porphyrin precursors
photosensitivity- porphyrins absorb light, cause cutaneous burning sensation
