Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Renal :') > Renal Approach to Proteinuria and Polyuria > Flashcards

Renal Approach to Proteinuria and Polyuria Flashcards

1
Q

What are the three layers of the glomerular filtration barrier?

A

1) fenestrated capillary endothelium 2) Glomerular Basement membrane 3) Podocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what is the function of the fenestrated capillary endothelium?

A

keeps out cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what is the function of the glomerular basement membrane?

A

it keeps out large plasma proteins (eg albumin)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what is the function of the podocytes?

A

it keeps out large plasma proteins (eg albumin)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

so what things get through the glomerular filtration barrier?

A

low molecular weight proteins, solutes and small molecules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what are 2 examples of low molecular weight proteins that get through the glomerular filtration barrier?

A

beta-2 macroglobulin and light chains

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what happens to the low molecular weight proteins that get through the glomerular filtration barrier?

A

they get filtered and then reabsorbed in the proximal tubule

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what are some examples of solutes and small molecules that get through the glomerular filtration barrier?

A

Na, K, and glucose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What makes up normal urine protein?

A

low-molecular weight proteins that pass through glomerular filtration barrier and don’t get reabsorbed; also includes Tamm-Horsfall protein produced by the renal tubule

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what is the normal daily protein excretion (both protein and albumin)?

A

protein: less than 150; albumin: less than 30

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what are the three different types of proteinuria?

A

glomerular, overflow, and tubulointerstitial

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what occurs in glomerular proteinuria?

A

there is damage to the glomerular filtration barrier–> albuminuria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what occurs in overflow proteinuria?

A

the filtered low-molecular weight protein load is greater than the reabsorptive capacity of the kidney (eg. light chains in multiple myeloma)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what occurs in tubulointerstitial proteinuria?

A

tubular damage leading to impaired reabsorption of low-molecular weight proteins (eg acute tubular necrosis)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

there are four different tests that can be ordered to test for proteinuria; what are they?

A

urinalysis, spot urine albumin/creatinine ratio, spot urine protein/creatinine ratio, and 24 hour urine protein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what are the pros of urinalysis?

A

cheap and easy; can detect other urine abnormalities

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what are the cons of urinalysis?

A

it only detects albumin; low sensitivity (only detects >300 mg protein)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what are the pros of the spot urine albumin/creatinine ratio?

A

it can detect small amounts of albumin (this is important in recognizing early diabetic nephropathy)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what are the cons of the spot urine albumin/creatinine ratio?

A

it only detects albumin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what are the pros of the spot urine protein/creatinine ratio?

A

detects all proteins (albumin, light chains, beta-2-macroglobulin)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what are the cons of the spot urine protein/creatinine ratio?

A

it is not as well validated in diabetic nephropathy patients

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what is the gold standard test for measuring proteinuria? but what is the con to this test?

A

24 hour urine protein; it is inconvenient

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

if you have a patient with known diabetic nephropathy, what tool used for measuring proteinuria would be best to use?

A

spot urine albumin/creatine ratio

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

what might the findings be on a spot urine albumin/creatinine ratio test in a patient with a light chain nephropathy (due to multiple myeloma)?

A

it may falsely show “no protein”- YOU NEED A SPOT URINE PROTEIN/CREATININE RATIO TO DETECT LIGHT CHAIN PROTEINURIA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

what are two specific conditions that cause glomerular proteinuria?

A

nephrotic and nephritic syndrome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

how does the urine appear in cases of nephrotic syndrome?

A

frothy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

losing albumin in the urine creates other problems throughout the body such as what?

A

peripheral edema and periorbital edema

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

besides albumin, what is another protein that may be lost in cases of nephrotic syndrome?

A

antithrombin III

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

what happens if a patient loses antithrombin III in cases of nephrotic syndrome?

A

it is an anticoagulant- so if you lose it, you are going to create a hypercoagulable state which can create a higher risk for blood clots like DVTs, PEs, and renal vein thrombosis

30
Q

which specific diseases do we most commonly see a hypercoagulable state?

A

membranous nephroapthy

31
Q

what is the effect of nephrotic syndrome on the liver?

A

the liver tends to ramp up production of lipoproteins and this can lead to hyperlipidemia

32
Q

the edema seen in nephrotic syndrome can be contributed to two different theories- what are they?

A

low intravascular oncotic pressure (underfill theory) and renal sodium retention (overfill theory)

33
Q

what are the 5 main features of nephrotic syndrome?

A

proteinuria (>3.5/day), ede,a, hyperlipidemia, hypoalbuminemia, hypercoagulability

34
Q

how does hyperlipidemia present in cases of nephrotic syndrome?

A

fatty cases and Xanthelasmas

35
Q

What are 5 examples of nephrotic syndromes?

A

diabetic nephropathy, minimal change disorder, focal segmental slomerulosclerosis, membranous nephropathy, amyloidosis

36
Q

what is the most common cause of nephrotic syndrome in children?

A

minimal change disorder

37
Q

what is focal segmental glomerulosclerosis associated with?

A

HIV, heroin use, and chronic reflux

38
Q

what is associated with membranous nephropathy?

A

hep b, hep c, syphilis, solid tumors, and SLE

39
Q

if you suspect a patient has nephrotic syndrome, what should their workup be?

A

serum creatinine with eGFR, urinalysis with microscopy, urine albumin to creatinine ratio and urine protein to creatinine ratio; additional labs: HIV, hep b/c serologies, SPEP, lipid panel, A1c

40
Q

how do you manage nephrotic syndrome, specifically the proteinuria aspect?

A

blood pressure control, ACE/ARB may be renoprotective

41
Q

what are the 4 main features of nephritic syndrome?

A

heamturia, proteinuria (<3.5), new-onset hypertension, AKI/oliguria

42
Q

what are the three broad categories that nephritic syndromes can be grouped into?

A
  1. immune complex 2. anti-GBM 3. ANCA-associated
43
Q

how can the immune-complex associated nephritic syndromes further be broken down?

A

low complement levels and normal complement levels

44
Q

what are the causes of immune complex associated nephritic syndromes with low complement levels?

A

post-strep, SLE

45
Q

what are the causes of immune complex nephritic syndromes with normal complement levels?

A

IgA nephropathy

46
Q

how can SLE nephritis present?

A

with other systemic findings (butterfly rash, polyarticular arthritis); or it could present with rapidly progressive glomerulonephritis

47
Q

what is the most common nephritic syndrome?

A

IgA nephropathy

48
Q

what are the pulmonary-renal nephritic syndromes?

A

anti-glomerular basement membrane (anti-GBM), GPA, MPA, and EGPA

49
Q

how does GPA present?

A

upper respiratory symptoms (saddle nose deformity, chronic sinusitis), lower respiratory symptoms (hemoptysis), renal symptoms (hematuria with severe AKI)

50
Q

what is microscopic polyangitis (MPA)?

A

think GPA without the upper respiratory symptoms

51
Q

how does EGPA present?

A

adult onset asthma, eosinophilia, palpable purpura, hematuria and AKI

52
Q

if you have a patient present with symptoms of a nephritic syndrome, what should their workup be?

A

serum creatinine with eGFR, urinalysis with microscopy, urine albumin to creatinine ratio and urine protein to creatinine ratio; additional labs: ANCA, anti-GBM, ANA, complements

53
Q

what is the urine sediment like in nephritic syndrome?

A

“active”: hematuria, dysmorphic RBCs, RBC casts, WBCs; non-nephrotic range proteinuria

54
Q

what is the urine sediment like in nephrotic syndrome?

A

“bland”: see heavy proteinuria but few cells

55
Q

what is the definition of polyuria?

A

production of more than 3 L of urine in 24 hours

56
Q

what are the 2 mechanisms in place to help the body regulate serum osmolality?

A

AND release and thirst

57
Q

how does ADH release work?

A

the hypothalamus has osmoreceptors that sense osmolality- ADH is going to go down the pituitary stalk and then travel to the kidneys where it binds to AVPR2

58
Q

what happens when ADH binds to AVPR2?

A

it causes aquaporins to move over to the apical surface of the cells, which allows water to move from the tubular lumen back into the blood

59
Q

what are the 4 causes of polyuria that we talked about?

A

osmotic diuresis, central diabetes insipidus, nephrogenic diabetes insipidus, primary polydipsia

60
Q

what is the mechanism of osmotic diuresis?

A

excess solute (glucose or mannitol) draws water into the renal tubules–> diuresis

61
Q

what is the mechanism of central diabetes insipidus?

A

lack of ADH–> inability to concentrate urine

62
Q

what is the mechanism of nephrogenic diabetes insipidus?

A

kidneys don’t respond to ADH

63
Q

what is the mechanism of primary polydipsia?

A

patient drinking excess H2O

64
Q

what are the key features of osmotic diuresis?

A

UA with glucosuria (if solute= glucose) and Uosm is >300

65
Q

what are 4 causes of central DI?

A

head trauma, brain tumor, congenital malformation, idiopathic

66
Q

what are the key features of central DI?

A

Uosm less than 300, urine osmolality does not increase with water deprivation, urine osmolality increases with administration of desmopressin (synthetic ADH)

67
Q

what is a common cause of nephrogenic DI?

A

medications such as lithium

68
Q

what are the key features of nephrogenic DI?

A

Uosm <300, urine osmolality does not increase with water deprivation, urine osmolality does not increase with the administration of desmopressin (synthetic ADH)

69
Q

does DI lead to hypernatremia?

A

if thirst mechanism is intact, then it won’t; patient compensates for ADH inactivity by drinking more water; if thirst mechanism is lost or patient lacks access to water, we can see hypernatremia

70
Q

what is primary polydipsia?

A

patient drinking excess water; commonly seen with psychiatric disorders including psychosis and OCD

71
Q

what are the key features associated primary polydipsia?

A

Uosm is less than 300, urine osmolality increases with overnight water deprivation

72
Q

how do you treat central diabetes insipidus?

A

drink more water; desmopressin

Renal :') (16 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions