Kidney, Urinary Tract and Electrolytes Flashcards
1
Q
subendothelial immune complex deposition is which pathology?
A
type I membranoproliferative glomerulonephritis
2
Q
what is bethanechol?
A
mAChR agonist used for acute neurogenic urinary retention
3
Q
pathophysiology of acute interstitial nephritis?
A
drug-induced hypersensitivity reaction involving the interstitium and tubules in the kidney, leads to AKI
4
Q
what molecules do you use to estimate GFR and RPF?
A
GFR = inulin, freely filtered and neither secreted nor resorbed
RPF = para-aminohippuric acid (PAH), combination of filtration and secretion means that all PAH entering the kidney is lost to the urine
5
Q
which disease predisposes to angiomyolipoma? what is this tumour?
A
tuberous sclerosis hamartoma of connective tissue
6
Q
2 classes of aetiology for acute tubular necrosis?
A
- nephrotoxic
- ischaemic –> consequence of prerenal AKI
7
Q
non-enzymatic glycosylation occurs preferentially at which site of the glomerulus in DM?
A
efferent arteriole leads to hyaline arteriolosclerosis, increased pressure in the glomerulus leading to hyperfiltration
8
Q
Minimal change disease histological findings? Immune fluorescence?
A
nil on light microscopy effacement of the podocyte foot processes on EM nil on IF
9
Q
what are the two main embryonic structues giving rise to kidey and what do they turn out to become?
A
- ureteric bud - ureters, calyx, pelvis, collecting ducts
- metanephric mesenchyme - glomerulus through DCT
10
Q
which diuretics lead to low urine Ca++
A
thiazides
11
Q
pathoG - muddy brown casts
A
acute tubular necrosis
12
Q
6 aetiologies of nephrotic sydnrome
A
- minimal change disease 2. focal segmental glomerulonephritis 3. membranous nephropathy 4. MPGN 5. diabetes mellitus 6. systemic amyloidosis
13
Q
what is the effect of ACE-I on glomerular filtration rate?
A
inhibit ACE, decrease AT II, prevent constriction of efferent arteriole
decreases GFR
14
Q
location of immune complex in membranoproliferative glomerulonephritis type 2 - ‘dense deposit disease’
associated condition
A
intramembranous
positive C3 nephritic factor (autoantibody), constituent conversion of C3, leading to nephritic syndrome
(lab finding = decreased circulating C3)
15
Q
a shrunken, cystic kidney suggests what pathology?
A
end-stage renal failure on dialysis
16
Q
association with horseshoe kidneys (2)
A
ureteropelvic junction obstruction and hydronephrosis
stones and infection
17
Q
focal segmental glomerular sclerosis disease association(s)
A
HIV, sickle cell disease, heroin abuse
18
Q
what is this?
underlying condition?
A
renal angiomyolipoma
associated with tuberous sclerosis
19
Q
nephrolithiasis shape = coffin lid, rectangular prism radio opaque
A
Magnesium ammonium phosphate (MAP)
20
Q
site of action of mannitol?
A
where the tubule is permeable to water freely
PCT and dLH
21
Q
in a woman, ureter passes infront of what artery and underneath what artery in the pelvis?
A
infront - internal iliac
behind - uterine (within uterosacral ligament)
22
Q
focal segmental glomerular sclerosis race association
A
Hispanic and African-American
23
Q
Churg-Strauss features (4)
A
- RPGN 2. asthma 3. eosinophilia 4. granulomatous inflammation
24
Q
nephrolithiasis shape = diamond or rhombus non radio opaque
A
urate
25
a heroin addict presents with nephrotic syndrome - what is the most likely pathology?
focal segmental glomerulonephritis
26
crystalisation of urate crystals occurs where in the nephron? why?
collecting ducts low pH
27
blood supply to the proximal ureters
blood supply to the distal ureteres
renal arteries
superior vesical arteries
28
spike and dome appearance on IF is suggestive of what pathology?
membranous nephropathy
29
patient with SLE develops nephritic syndrome. what is the most likely pathology?
diffuse proliferative glomerulonephritis which is one of the Rapidly Progressive Glomerulonephritides
30
RPGN IF findings = granular (2)
Immune complex mediated PSGN or diffuse proliferative glomerulonephritis
31
equation for filtration fraction?
FF = GFR/RPF
32
major complication of PSGN?
rapidly progressive glomerulonephritis - renal failure in weeks to months
33
metolazone is what?
thiazide diuretic
34
what is the normal handling of potassium along the nephron?
free filtration at the glomerulus, 70% isotonic resporption at PCT
20-25% resorption across NKCC in TALH
point of control = DCT and collecting duct
excretion through principal cells (Na/K ATPase), resorption in alpha-intercalated cells
increase excretion = high extracellular K+, aldosterone, alkalosis
35
nephrolithiasis shape = hexagon radio opaque
cystine
36
3 diseases associated with Wilms tumour
1. WAGR 2. Denys-Drash syndrome 3. Beckwith-Wiedemann syndrome
37
5 nephrotoxins that can cause acute tubular necrosis?
uric acid - tumour lysis syndrome
aminoglycosides
ethylene glycol (associated oxalate crystals in urine)
heavy metals - lead
myoglobin (crush injury)
38
what are the nephrotoxic effects of amphotericin B?
decreased GFR and direct toxicity to the epithelium
results in anaemia (decreased EPO), hypokalaemia/hypoMg++
39
asymptomatic with one hypertrophied kidney at birth?
congential solitary functioning kidney
40
EPO is produced by which cells?
renal peritubular interstitial cells
41
what is normal GFR?
125 mL/min
42
2 clinical features of renal papillary necrosis?
gross haematuria and flank pain
43
what is the final structure of the developing kidney to canalize?
uteropelvic junction - detected on USS as hydronephrosis
most common site of obstruction
44
what is the benefit of ARB over ACE-I?
does not give bradykinin symptoms
45
functional definition of nephrotic syndrome
\> 3.5 g/day protein in 24 hour urine collection
46
4 causes of renal papillary necrosis
1. analgesic abuse (aspirin or pheacetin) 2. diabetes mellitus 3. sickle cell disease (or trait) 4. severe, acute pyelonephritis
47
isolated haematuria & hearing loss suggest?
Alport syndrome (also ocular disturbance and X-linked inheritance pattern)
48
which diuretics lead to acidaemia?
1. carbonic anhydrase inhibitors (acteazolamide)
2. potassium sparing diuretics
**reduced secretion** of K+/H+ in DCT/CD; **hyperkalaemia** forces protons out of cells through K+/H+ antiporter
49
which diuretics cause an increase in urine potassium?
mostly loop and thiazide diuretics, hence hypoK+
50
what is the site of action of acetazolamine in the nephron?
PCT and dLH
51
which diuretics lead to alkalosis and what are the 3 mechanisms?
loop diuretics and thiazides
1. **contraction alkalosis** - total volume decrease, RAAS activation, Na+/H+ resorption in PCT, HCO3- follows, total body bicarb increases
2. loss of K+, **hypokalaemia** pulls K+ out of cells forcing H+ into cells out of plasma
3. **paradoxical aciduria** - hypokalaemia means H+ rather then K+ is secreted for Na+ resorption in DCT/CD across Na+/K+ transporter
52
RPGN IF findings = linear (1)
Goodpasture IgA bound in a line to GBM
53
prenatal hydronephrosis and thickened bladder wall suggests...?
posterior urethral valve
only in males, most common bladder outlet obstruction
54
patient with SLE develops nephrotic syndrome. what is the most likely pathology?
membranous nephropathy
55
4 blood findings with nephrotic syndrome
1. hypoalbuminaemia 2. hypogammaglobulinaemia 3. hypercholesterolaemia 4. hypercoagulability - selective loss of antithrombin III
56
subepithelial immune complex deposition is which pathology?
membranous nephropathy
57
renal blood flow = 1.0
GFR = 0.1
haematocrit = 0.5
what is the filtration fraction?
FF = GFR/RPF; _RPF = RBF \* (1 - Hct)_
FF = (0.1) / _(1.0 - 0.5)_ = **0.2**
58
bugs causing cystitis
E Coli (80%) Staph saprophyticus (young, sexually active women) Klebs pneumoniae Proteus - alkaline urine Enterococcus faecalis
59
what is the site and mechanism of action of potassium sparing diuretics?
DCT and collecting duct
Na+ channel blockers/reduce expression
60
where is the site of PTH action in the nephron? what channel and what is the net result?
_proximal CT_
inhibits NaPi cotransport, increasing PO43- excretion
_distal CT_
stimulates Na+/Ca++ exchange at the basolateral surface, increasing Ca++ resorption
61
how long following an episode of acute tubular necrosis does normal kidney function return?
3 weeks
62
location of immune complex in membranoproliferative glomerulonephritis type 1
associated condition
subendothelial
Hepatitis B & C
63
what's the formula for clearance of substance in the kidney?
clearance of 'x' = [x]urine \* (urine flow)/[x]plasma
urine flow usually in mL/min, just make sure units for concentration are equivalent
64
pathoG Kimmelstiel-Wilson
Diabetes mellitus sclerotic nodules formed in the glomerular mesangium
65
what are the adverse effects of potassium sparing diuretics?
hyperkalaemia
spironolactone = anti-androgen effects (gynaecomastia)
66
where does horseshoe kidney get stuck?
inferior mesenteric artery
67
pathoG - eosinophil in urine
acute interstitial nephritis
68
caudal end of mesonephric duct (mesoderm) produces what structure?
bladder trigone
where the rest of the bladder is endoderm
69
what are the metabolic effects of loop diuretics?
1. hypokalaemia
2. contraction alkalosis (activation of RAAS following contraction dumps H+ in exchange for Na+)
70
which kidney do you take in transplant donation and why?
left kidney b/c longer renal vein
71
membranous nephropathy is associated with which 4 conditions?
SLE HBV HCV solid tumours
72
what does mesonephros do?
interim kidney for 1st trimester then degenerates
forms part of male genital system
73
focal segmental glomerular sclerosis histological findings? EM/Immune fluorescence?
sclerosis (collagen deposition) of only a segment of the glomerulus (H&E)
effacement of the podocyte foot processes on EM
nil on IF
74
complications of duplex collecting system
viscoureteric reflux and ureteral obstruction (UTIs)
75
pathoG - white blood cell cast
pyelonephritis
76
RPGN IF findings = negative (3)
Wegener's granulomatosis (cANCA) microscopic polyangiitis (pANCA) Churg-Strauss syndrome (pANCA)
77
tumour lysis syndrome prophylaxis
1. adequate hydration (good GFR, less likely to build up toxins in tubule) 2. allopurinol - limit the conversion of amino acids to uric acid all in one go
78
the classic triad of RCC
haematuria palpable mass flank pain
79
what is the most common cause of nephrotic syndrome in otherwise healthy Caucasian adults?
membranous nephropathy
80
immune signalling mechanism leading to glomerular inflammation in nephritic syndrome
1. immune complex deposition
2. activation of complement C5a
3. activation attracts neutrophils (hypercellular on H&E)
4. neutrophils mediate inflammation and damage
81
a large, cystic kidney suggests what pathology?
polycystic kidney disease
82
what is the mechanism of acyclovir nephrotoxicity?
renal excretion
if concentration builds up in collecting duct then crystalisation and renal tubular damage will occur
prophylaxis with aggressive IV fluids
83
what is the site and mechanism of action for thiazide diuretics?
inhibit NaCl reabsorption in DCT
reduces Ca+ excretion
84
pathoG waxy casts
chronic pyelonephritis, chronic kidney disease, end-stage renal failure
85
what are the adverse effects of foscarnet and what are the mechanisms?
hypocalaemia and hypomagnesaemia
1. direct chelator of calcium
2. renal wasting of magnesium, decrease PTH, exacerbate hypoCa++
86
nephrolithiasis shape = octahedron radio opaque
calcium oxalate
87
pathoG subepithelial hump
post streptococcal glomerulonephritis
88
what are the adverse effects of loop diuretics?
## Footnote
*think: direct effect, metabolic disturbance, hypersensitivity*
ototoxicity
hypoK+/Mg++, metabolic alkalosis
sulfa allergy/interstitial nephritis
89
which drug therapy is best management to prevent development of renal failure in a diabetic?
ACE inhibitor
90
what is the effect of the sympathetic nervous system on RAAS?
sympathetic action on beta1-adrenoceptors on macula densa increases renin secretion
beta-blockers main action on *hypertension* is through decreasing RAAS
91
failure of the ureteric bud to induce proper differentiation of the metanephric mesenchyme results in what disease?
multicystic dysplastic kidney
92
gold standard for UTI diagnosis
\>100,000 colony forming units on urine culture
93
what embryonic tissue gives rise to the kidneys?
metanephros
94
brown, granular casts in the urine suggests what pathology?
acute tubular necrosis necrotic cells plug the tubule, casting into shape and obstructing flow, decreasing GFR. eventually pass through into the urine
95
chlorthialidone is what?
thiazide diuretic
96
when does pronephros degenerate?
by week 4
97
what is the site and mechanism of action of loop diuretics?
2 examples
thick ascending LH
inhibit NKCC cotransport, natriuresis.
increase excretion of Ca++ *'loops lose Ca++'*
furosemide, bumetanide, torsemide, ethacrynic acid (nonsulfa drug)
98
presence of 'M protein' refers to which organism? what is the clinical relevance?
group A beta-haemolytic streptococcus increases the chance of developing PSGN following skin or pharynx infection
99
what are the benefits and risks of using ethacrynic acid over furosemide?
cannot induce sulpha allergy
more ototoxic
100
pathoG red cell cast
nephritic syndrome glomerular bleeding
101
what are the histopathologic findings in membranous nephropathy?
light microscopy = thickened GBM EM = subepithelial immune complex deposit with 'spike & dome' appearance IF = granular deposits
102
biopsy - uniform, diffuse thickening of the basement membrane without an increase in cellularity suggests which pathology?
membranous glomerulopathy
103
what are the adverse effects of thiazide diuretics?
hypoK+/Na+ metabolic alkalosis
hyper**GLUC** -**g**lycaemia, **l**ipidaemia, **u**raemia, **c**alcaemia
104
triamterene is what?
Na+ channel blocker in cortical collecting duct, K+-sparing diuretic
same action as amiloride
105
acetazolamide causes alkalosis or acidosis?
reduces resorbtion of bicarb, so you lose total body HCO3-
Resulting in **acidosis**
106
decreased kidney perfusion causing pre-renal AKI affects which portion(s) of the nephron first?
proximal convoluted tubule and thick ascending limb of loop of henlé - both in renal medulla which has poor oxygen supply even in physiological conditions
107
glomerular sclerosis and hyalinosis would suggest which pathology?
diabetic nephropathy
108
intramembranous immune complex deposition is which pathology?
type II membranoproliferative glomerulonephritis
109
eplerenone is what?
aldosterone antagonist, K+-sparing diuretic
110
nonfunctional kidney consisting of cysts and connective tissue..
diagnosis?
mutlicystic dysplastic kidney
111
which diuretics lead to loss of Ca++
loop diuretics
112
renin is released by which cells in the kidney?
juxtaglomerular cells which are modified smooth muscle cells located around the wall of the afferent arteriole
