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Flashcards in Renal USMLE Deck (167)
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1
Q

ureters pass _______ uterine artery and ______ ductus deferens (retroperitoneal)

A

UNDER,UNDER

mneu: water (ureters) UNDER the bridge (artery, ductus deferens).

2
Q

total body weight is ____% water

A

60

3
Q

total body water is ___ intracellular fluid

A

2/3

4
Q

total body water is 1/3 extracellular fluid what portion of this is plasma volume

A

1/4

5
Q

ICF=

A

TBW-ECF

6
Q

interstitial volume-

A

ECF-PV

7
Q

60-40-20 rule (% of body weight)

A

60% total body water
40% ICF
20% ECF

8
Q

plasma volume can be measured by this

A

radiolabeled albumin

9
Q

extracellular volume can be measured by this

A

inulin

10
Q

Cx=

A

UxV/P=volume of plama from which the substance is cleared completely per unit time

Cx=clearance of X
Ux=urine concentration of X
Px=Plasma concentration of X
V=urine flow rate

11
Q

if Cx < GFR, then there is net tubular ________ of X

A

resorption

12
Q

if Cx > GFR, then there is net tubular ________ of X

A

secretion

13
Q

if Cx = GFR, then ___________

A

no net secretion or reabsorption

14
Q

glomerular filtration barrier is responsible for filtration of plasma according to these 2 factors

A

size and net charge

15
Q

what is the glomerular filtration barrier composed of

A

1) fenestrated capillary endothelium (size barrier)
2) Fuse basement membrane with heparan sulfate (negative charge barrier)
3) epithelial layer consisting of podocyte foot processes

16
Q

what barrier of the glomerular filtration barrier is lost in nephrotic syndrome

A

charge barrier

17
Q

what are some symptoms of nephrotic syndrome

A

albuminuria, hypoproteinemia, generalized edema, and hyperlipidemia

18
Q

what is used to calculate GFR because it is freely filtered and is neither reabsorbed nor secreted

A

inulin

19
Q

creatinine clearance is an approximate measure of what

A

GFR

20
Q

GFR=

A

U(inulin)xV/P(inulin)=C(inulin)

21
Q

effective renal plasma flow (ERPF can be estimated using _____ because it is both filtered and actively secreted in the proximal tubule. All _____ entering the kidney is excreted.

A

PAH

22
Q

ERPF=

A

U(PAH)xV/P(PAH)=C(PAH)

23
Q

RBF=

A

RPF/1-Hct

24
Q

ERPF underestimates true RPF by how much?

A

~10%

25
Q

filtration fraction (FF)=

A

GFR/RPF

26
Q

what effect will afferent arteriole constriction have on
RPF:
GFR:
FF (GFR/RPF):

A

RPF:↓
GFR:↓
FF (GFR/RPF):NC

27
Q

what effect will efferent arteriole constriction have on
RPF:
GFR:
FF (GFR/RPF):

A

what effect will afferent arteriole constriction have on
RPF:↓
GFR:↑
FF (GFR/RPF):↑

28
Q

what effect will increased plasma protein concentration have on
RPF:
GFR:
FF (GFR/RPF):

A

RPF:NC
GFR:↓
FF (GFR/RPF):↓

29
Q

what effect will decreased plasma protein concentration have on
RPF:
GFR:
FF (GFR/RPF):

A

RPF: NC
GFR: ↑
FF (GFR/RPF):↑

30
Q

what effect will constriction of ureter have on
RPF:
GFR:
FF (GFR/RPF):

A

RPF: NC
GFR:↓
FF (GFR/RPF):↓

31
Q

free water clearance

C(H2O)=

A

V-C(osm)

V=urine flow rate

32
Q

glucose at a normal level is completely reabsorbed where

A

proximal tubula

33
Q

at plasma glucose of _____, glucosuria begins (threshold)

A

200mg/dL

34
Q

at plasma glucose level of ______, transport mechanism is saturated (Tm)

A

350 mg/dL

35
Q

amino acid resorption occurs by at least 3 distinct carrier systems, with competitive inhibition within each group. Secondary active transport occurs in the _________ and is saturable.

A

proximal tubule

36
Q

what effect will decreased plasma protein concentration have on
RPF:
GFR:
FF (GFR/RPF):

A

RPF: NC
GFR:↑
FF (GFR/RPF):↓

37
Q

what effect will constriction of ureter have on
RPF:
GFR:
FF (GFR/RPF):

A

RPF: NC
GFR:↓
FF (GFR/RPF):↓

38
Q

free water clearance

C(H2O)=

A

V-C(osm)

V=urine flow rate

39
Q

glucose at a normal level is completely reabsorbed where

A

proximal tubula

40
Q

at plasma glucose of _____, glucosuria begins (threshold)

A

200mg/dL

41
Q

this part of the nephron is called the “workhorse of the nephron”

A

early proximal convuluted tubule.

42
Q

the early proximal convuluted tubule resorbes all of these 2 things and most of these 3 things

A

all of glucose and amino acids

most of the bicarb, sodium, and water

43
Q

the early proximal convuluted tubule secretes this which will act as a buffer for secreted H+

A

ammonia

44
Q

this part of the nephron passively reabsorbs water via medullary hypertonicity (impermeable to sodium)

A

thin descending loop of Henly

45
Q

this part of the nephron actively reabsorbs Na+, K+, and Cl- and indirectly induces the reabsorption of Mg++ and Ca++. It is impermeable to H2O

A

Thick ascending loop of Henle

46
Q

the early distal convuluted tubule actively reabsorbs these 2 ions. Here reabsorbion of Ca++ is under the control of PTH

A

Na+, Cl-

47
Q

the collecting tubules resorb Na_ in exchange for secreting K+ or H+. This is regulated by this hormone

A

aldosterone

48
Q

in the collecting tubules resorption of water is regulated by this hormone

A

ADH (vasopressin)

49
Q

osmolarity of medulla can reach ______mOsm

A

1200

50
Q

this is released by the kidneys upon sensing decreased BP

A

renin

51
Q

renin cleaves angiotensinogen to this

A

ATN I (a decapeptide)

52
Q

ATN I is cleaved by this enzyme, primarily in the lung capillaries and elsewehere, to ATN II (an osctapeptide)

A

Angiotensin-converting enzyme (ACE)

53
Q

what are the actions of angiotensin II

A

1) potent vasoconstriction
2) release of aldosterone from the adrenal cortex
3) release of ADH from posterior pituitary
4) stimulates hypothalamus to increase thirst

54
Q

what is the overal purpose of ATN II

A

increase intravascular volume and BP

55
Q

this peptide released from atria may acti as a “check” on the renin-angiotensin system (e.g., in heart failure).

A

ANP

56
Q

these are modified smooth muscle cells of afferent arteriole

A

JG cells

57
Q

this is a Na+ sensor and part of the distal convoluted tubule

A

macula densa

58
Q

JG cells secrete this in resoponse to low renal blood pressure, low Na+ delivery to distal tubule, and increased sympathetic tone

A

renin

59
Q

what does the juxtaglomerular apparatus (JGA) consist of

A

JG cells and macula densa

60
Q

when the JG cells secrete renin what does this lead to

A

increase in ATN II and aldosterone

61
Q

JGA activates the renin-angiotensin system in defence of this

A

glomular filtration rate

62
Q

juxta means

A

close by

63
Q

Endocrine fxs of kidney: endothelial cells of peritubular capillaries secrete this in response to hypoxia

A

erythropoeietin

64
Q

Endocrine fxs of kidney: conversion of 25-OH vit D to ________ by 1alpha-hydroxylase, which is activated by PTH

A

1,25-(OH)2 vit D

65
Q

Endocrine fxs of kidney: JC cells secrete ____ in response to decrease renal arterial pressure and increase renal sympathetic discharge (B1 effect)

A

renin

66
Q

Endocrine fxs of kidney: secretion of _________ that vasodilate the afferent arterioles to increase GFR

A

prostaglandins

67
Q

this common class of drug can cause acute renal failure in high vasoconstrictive states by inhibiting the renal production of prostaglandins, which keep the afferent arterioles vasoldilated to maintain GFR

A

NSAIDs

68
Q

Hormones acting on the kidney:

This hormone is secreted in response to increased atrial pressure and causes increase GFR and increase Na+ excretion

A

atrial natriuretic factor (ANF)

69
Q

Hormones acting on the kidney: This hormone is secreted in response to decreased blood volume (via AT II) and increased plasma [K+]. It causes increased Na+ reabsorption, increase K+ secretion, increase H+ secretion

A

aldosterone

70
Q

Hormones acting on the kidney:

This hormone is secreted in response to low blood volume.

A

renin

71
Q

where is ATN I converted to ATN II by ACE

A

lung

72
Q

Hormones acting on the kidney:

This hormone causes efferent arteriole constriction which leads to increase GFR and increase Na+ and HCO3- reabsorption

A

Angiotensin II

73
Q

Hormones acting on the kidney:
This hormone is secreted in response to increase plasma osmolality and decreased blood volume. It binds to receptors on principal cells, causing increase number of water channels and increased H2O absorption

A

vasopressin/ADH

74
Q

Hormones acting on the kidney:
This hormone is secreted in response to low plasma [Ca++]. It causes increase [Ca++] reabsorption (DCT), decrease PO4— reabsorrption (PCT, 1,25 (OH)3 vit D production ->increase Ca_ and PO4— resorptioon

A

PTH

75
Q
Acid Base Physiology:
Metabolic acidosis=
pH:
Pco2:
[HCO3-]:
compensatory response:
A

pH:↓
Pco2:↓
[HCO3-]:↓*
Compensatory response: hyperventilation

76
Q
Acid Base Physiology:
Metabolic alkalosis=
pH:
Pco2:
[HCO3-]:
compensatory response:
A

pH:↑
Pco2:↑
[HCO3-]:↑*
Compensatory response: hypoventilation

77
Q
Acid Base Physiology:
respiratory alkalosis=
pH:
Pco2:
[HCO3-]:
compensatory response:
A

pH:↑
Pco2:↓*
[HCO3-]:↓
Compensatory response: renal [HCO3-] reabsorption

78
Q
Acid Base Physiology:
respiratory acidosis=
pH:
Pco2:
[HCO3-]:
compensatory response:
A

pH:↓
Pco2:↑*
[HCO3-]:↓
Compensatory response: renal [HCO3-] secretion

79
Q

what is the Henderson-Hasselbach equasion

pH=

A

pKa + log [HCO3-]/0.03 P(co2)

80
Q

acid base compensations: metabolic acidosis

A

winter’s formula:

Pco2=1.5 (HCO3-) + 8 +/- 2

81
Q

acid base compensations: metabolic alkalosis

A

pco2 ↑ O.7 per

1 HCO3-↑

82
Q

acid base compensations: respiratory acidosis

A

acute-↑1HCO3- per 10CO2↑

chronic-↑3.5HCO3- per 10CO2↑

83
Q

acid base compensations: respiratory alkalosis

A

acute-↓2HCO3- per 10CO2↓

chronic-↓5HCO3- per 10CO2↓

84
Q

this syndrome is due to a bilateral renal agenesis which leads to oligohydramnios. This results in limb deformities, facial deformities, and pulmonary hypoplasia

A

Potter’s syndrome

mneu: babies w/ Potter’s can’t “Pee” inutero

85
Q

what is the embryological malformation which leads to Potters syndrome

A

malformation of ureteric bud

86
Q

this occurs when the inferior poles of both kidneys fuse.

A

horseshoe kidney

87
Q

when a horshoe kidney ascends from the pelvis during fetal development the kidneys get trapped under this artery and remain low in the abdomen

A

inferior mesenteric

88
Q

RBC casts in urine what is your differential

A

glomerular inflammation (nephritic syndromes), ischemia, or malignant hypertension

89
Q

WBC casts in urine what is your differential

A

tubulointerstitial dz, acute pylonephritis, glomerular disorders

90
Q

granular casts in urine what is it

A

acute tubular necrosis

91
Q

waxy casts in urine what is it

A

advanced renal dz/CRF

92
Q

presence of these indicates that hematuria/pyruia is of renal origin

A

casts

93
Q

what type of blood cell do you see in the urine with bladder cancer

A

RBCs

94
Q

what type of blood cell do you see in the urine with acute cystitis

A

WBCs

95
Q

NephrItic syndrome is characterized by

A

I=inflammation

96
Q

what signs and symptoms will you see in nephritic syndrome

A

hematuria, hypertension, oliguria, azoemia

97
Q

give 6 examples of nephritic syndrome

A

1) acute poststreptococcal glomerulonephritis
2) rapidly progressive (crescentric) glomerulonepritis
3) Good pasture syndrome
4) membranoproliferative glomerulonepritis
5) IgA nephropathy (Berger’s dz)
6) Alport’s syndrome

98
Q

this nephritic syndrome is most frequently seen in children. It may present with peripheral and periorbital edema. On light microscope the glomeruli may appear enlarged and hypercellular. There is a “lumpy bumpy apprearance. Neutrophils are presence. Elecron microscopy shows subepithelial humps. Immunoflurescent shows a granular pattern. It resolves spontaneously.

A

Acute postreptococcal glomerulonephritis

99
Q

this nephritic syndrome has many causes it is characterized by a rapid course to renal failure. LM & IF shows crescent moon shape

A

rapidly progressive (crescentic glomerulonephritis

100
Q

this nephritic syndrome often presents with hemoptysis or hematuria. IF shows a linear pattern and anti-GBM antibodies

A

Goodpasture’s syndrome

101
Q

what type of hypersensitivity is goodpasture’s syndrome

A

type II

102
Q

this nephritic syndrome slowly progresesses to renal failure. EM shows subendothelial humps, “tram track.”

A

membranoproliferative glomerulonephritis

103
Q

this nephritic syndrome is often postinfectious. It is mild and IF and EM show mesangial deposits of IgA

A

IgA nephropathy (Berger’s dz)

104
Q

this nephritic syndrome is a collagin IV mutation. There is a split basement membrane. It is often manifested by nerve deafness and ocular disorders.

A

Alport’s syndrome

105
Q

NephrOtic syndrome is characterized by this

A

O=protinurea

106
Q

what are the signs and symptoms of nephrotic syndrome

A

massive protinuria, hypoalbuminemia, peripheral and periorbital edema, hyperlipidemia

107
Q

give 5 causes of nephrotic syndrome

A

1) membranous glomerulonephritis
2) minimal change dz (lipoid nephrosis)
3) focal segmental glomerular sclerosis
4) diabetic nephropathy
5) SLE

108
Q

this is a common cause of nephrotic syndrome in adults. LM: diffuse capillary and basement membrane thickening. IF: granular pattern. EM: “spike and dome”

A

membranous glomerulonephritis

109
Q

this is a common cause of nephrotic syndrome in children. LM: normal glomeruli. EM foot process effacement.

It responds well to steroids

A

minimal change dz (lipoid nephrosis)

110
Q

this type of nephrotic syndrome shows segmental sclerosis and hyalinosis under LM. It causes a more severe dz in HIV pts

A

Focal segmental glomerular sclerosis

111
Q

this nephrotic syndrome shows Kimmelsteil Wilson “wire loop” lesions and basement membrane thickening in light microscope

A

diabetic nephropathy

112
Q

this cause of nephrotic syndrome has 5 patterns of renal involvement. LM: in membranous glomerulonephritis pattern, wire-looped lesion with subendothelial deposits

A

SLE

113
Q

kidney stones can lead to severe complications such as

A

hydronephrosis and pyelonephritis

114
Q

this is the most common kidney stone (75-85%). They tend to recur.

A

calcium (calcium oxalate or calcium phosphate)

115
Q

Ca++ kidney stones are radio____

A

opaque

116
Q

what are some syndromes that can cause calcium kidney stones

A

Cancer, increase PTH, increase vit D, milk alkali syndrome.

117
Q

this is the 2nd most common kidney stone. It is caused by infection with urease-positive bugs (Proteus vulgaris, staphylococcus, Klebsiella). They can form Staghorn calculi that can be a nidus for UTIs

A

Ammonium magnesium Phosphate (struvite)

118
Q

Ammonium magnesium Phosphate (struvite) stones are radio_____

A

opaque

119
Q

this type of kidney stone has a strong associateion with hyperuricemia (e.g., gout). Often seen in dzz with increase cell turnovers, such as leukemia and myeloproliferative disorders

A

uric acid

120
Q

uric acid stones are radio____

A

lucent

121
Q

this type of kidney stone is most often secondary to cystinuria

A

cystine

122
Q

cystine stones are most often secondary to cystinuria and are radio______

A

faintly radiopaque

123
Q

this is the most common renal malignancy. It is most common in men ages 50-70. There is increased incidence with smoking and obesity. It manifests clinically with hematuria, palpable mass, secondary polycythemia, flank pain, fever, and weight loss.

A

renal cell carcinoma

124
Q

renal cell carcinoma is associated with this dz and gene deletion

A

von Hippel-Lindau and gene deletion in chromosome 3

125
Q

renal cell carcinoma originates in renal tubule cells and spreads to the polygonal clear cells. It invades the IVC and spreads thorugh this route

A

hematogenously.

126
Q

renal cell carcinoma is commonly associated with paraneoplastic syndromes. give some examples.

A

ectopic EPO, ACTH, PTHrP, and prolactin

127
Q

this is the most common renal malignancy of early childhood (ages 2-4). Presents with huge palpable flank mass, hemihypertrophy.

A

Wilms tumor

128
Q

Wilms tumor is associated with deletion of this tumor suppressior gene on this chromosome

A

WT1 on chromosome 11

129
Q

Wilms tumor can be part of WAGR complex. What is this

A

wilms’ tumor
Aniridia
GU malformation,
mental motor retardation

130
Q

this is the most common tumor of urinary tract system (can occur in renal calyces, renal pelvis, ureters, and bladder).

A

transitional cell caricinoma

131
Q

this is suggestive of bladder cancer

A

painless hematuria.

132
Q

transitional cell caricinoma is associated with problems in your Pee SACS (mneu). What does this mean

A
Phenacetin
Smoking
Aniline dyes
Cyclophosphamide
Schistosomiasis
133
Q

pt presents w/ fever and CVA tenderness. What do you suspect?

A

acute pyelonephritis

134
Q

what part of the kidney does acute pyelonephritis effect

A

affects cortex w/ relative sparing of glomeruli/vessels.

135
Q

what is pathognomonic for acute pyelonephritis

A

white cell casts in urine

136
Q

this conditon is characterized by coarse, asymmetric corticomedullary scarring.

A

chronic pyelonephritis

137
Q

chronic pyelonephritis looks like this tissue histologically

A

thyroid (thyroidization of kidney)

138
Q

In chronic pyelonephritis, tubules contain ______ casts

A

eosinophilic

139
Q

this is caused by an acute generalized infarction of the cortices of both kidneys. It is likely due to a combination of vasospasm and DIC. It is associated with obstetric castrophes (e.g., abruptio placentae) and septic shock

A

Diffuse cortical necrosis

140
Q

this is the most common cause of acute renal failure. It is reversible, but fatal if left untreated. It is associated with renal ischemia (e.g., shock), crush injury (myoglobinuria), toxins. Death most often occurs during the initial oliguric phase. Recovery is in 2-3 weeks.

A

acute tubular necrosis

141
Q

renal papillary necrosis is associated with four conditions

A

1) diabetes mellitus
2) acute pyelonephritis
3) chronic phenacetin use
4) sickle cell anemia

142
Q

this is associated with an abrupt decline in renal fx with increased creatinine and BUN over a period of several days

A

acute renal failure

143
Q

this type of acute renal failure is characterized by decreased RBF (e.g., hypotension) ->decreased GFR. Na+/H2O are retained by the kidney.

Labs:
Urine osmo: >500
Urine Na+: 20

A

prerenal failure

144
Q

this type of acute renal failure is generally due to acute tubular necrosis or ischemia/toxins. Patchy necrosis leads to debris obstructing tubule and fluid backflow across necrotic tubule -> decreased GFR. Urine has epithelial/granular casts.

Labs:
Urine osmo: 20
Fe(Na): >2%
BUN/Cr ratio:

A

intrinsic renal failure

145
Q
this type of acute renal failure is due to outflow obstruction (stones, BPH, neoplasia).  Develops only with bilateral obstruction 
Labs:
Urine osmo: 40
Fe(Na): >4%
BUN/Cr ratio: >15
A

Postrenal failure

146
Q

acute renal failure is often due to this

A

hypoxia

147
Q

chronic renal failure is often due to these two chronic dz

A

htn

dbts

148
Q

renal failure results in a failure to make urine and a failure to excrete this type of waste

A

nitrogenous

149
Q

this is a clinical sydrome marked by increase BUN and creatinine and associated symptoms

A

uremia

150
Q

renal failure can result in anemia. why?

A

failure of erythropoitetin production

151
Q

renal failure can result in renal osteodystrophy. why?

A

failure of active vit D production

152
Q

renal failure can result in cardiac arrhythmias. why?

A

hyperkalemia

153
Q

renal failure can result in metabolic acidosis. why?

A

decreased acid secretion and decrease generation of HCO3-

154
Q

renal failure can result in CHF and pulmonary edema. why?

A

Na+ and H2O excess

155
Q

what are some other things renal failure can result in?

A

uremic encephalopathy
chronic pyelonephritis
hypertension

156
Q

low serum Na+ results in

A

disorientation, stupor, coma

157
Q

high serum Na+ results in

A

neurologic: irritability, delirium, coma

158
Q

low serum Cl- is often secondary to this

A

metabolic alkalosis

159
Q

high serum Cl- is often secondary to this

A

non-anion gap acidosis

160
Q

low serum K+ results in

A

U waves on ECG, flattened T waves, arrhythmias, paralysis

161
Q

high serum K+ results in

A

peaked T waves, arrhytmias

162
Q

low serum Ca++ results in

A

tetany, neuromuscular irritability

163
Q

high serum Ca++ results in

A

delirium, renal stones, abdominal pain

164
Q

low serum Mg++ results in

A

neromuscular irritability, arrhythmias

165
Q

high serum Mg++ results in

A

delirium, decreased DTRs, cardiopulmonary arrest

166
Q

low serum PO4– results in

A

low-mineral ion product causes bone loss

167
Q

high serum PO4– results in

A

low-mineral ion product causes metastatic calcification, renal stones