Renal Flashcards
1
Q
What is the proximal tubular fluid/plasma ultrafiltrate ratio?
A
Concentration of a substance in the proximal tubule/ initial concentration of the substance in Bowman’s Space.
Positive ratio: freely filtered, poorly resorbed
- PAH, Cr, inulin > urea
Net zero: Na, K (same as water)
Negative ratio: resorbed
- Glucose, amino acids > bicarb
2
Q
What species causes urinary schistosomiasis?
A
S. hematobium
- North Africa
- Sub-Saharan Africa
- Middle East
vs. S. mansoni and S. japonicum, which cause intestinal and hepatic schistosomiasis
3
Q
What are the symptoms of S. hematobium?
A
Causes urinary schistosomiasis
- Terminal hematuria
- Frequent urination
- Hydronephrosis
- Pyelonephritis
- SCC of bladder
4
Q
What enzyme converts pyruvate to acetyl coA?
A
Pyruvate dehydrogenase
Because this is an aerobic process (start of Kreb’s Cycle), deficiency causes:
- Metabolic acidosis
- High anion gap
- High plasma lactate
5
Q
What chronic condition are Kimmelstiel-Wilson nodules associated with?
A
Diabetes
KW Nodules are:
- In the peripheral mesangium
- Ovoid or spherical
- Lamellated in appearance
- Eosinophilic on H&E
- PAS +
6
Q
What is Henoch-Schonlein Disease?
A
- Skin: purpura
- GI: abdominal pain, vomit, intestinal bleeding, intussusspetion
- Renal: IgA Nephropathy
7
Q
What does Calcinuerin do?
A
Essential for activation of IL-2, which promotes growth/diff of T cells.
Immunosuppressants like cyclopsorine and tacrolimus work by inhibiting calcineurin.
8
Q
What is the role of eosinophils in parasitic defense?
A
- Parasite entering mucosa or bloodstream is coated by IgE and IgG.
- These Abs bind the Fc receptors on eosinophil cell surface.
- Triggers eosinophil degranulation and release of cytotoxic proteins (ex. major basic protein)
Antibody Dependent Cell Mediated Cytotoxicity (ADCC)
- Alsomacros, neutros, NK cells
9
Q
What are the findings of Conn’s Syndrome?
A
Aldo secreting tumor
- HTN from increased Na
- Met alkalsosis from lost H, K
- Decreased plasma renin
10
Q
What is the Rx for Conn’s Syndrome?
A
Spironolactone or eplerenone, aldo antagonists
11
Q
What is stress incontinence?
A
Lose urethral support
Intrabdominal pressure > urethral sphincter pressure
Sx: leaking with coughing, sneezing, laughing, lifting
12
Q
What is urge incontinence?
A
Detrusor overactivity
Sx: sudden overwhelming or frequent need to empty bladder
ex. MS
13
Q
What is overflow incontinence?
A
Impaired Detrusor contractility, bladder outlet obstruction
Sx: constant involuntary dribbling of urine, incomplete emptying
14
Q
In what part of the nephron does ADH work?
A
MEDULLARY portion of the collecting duct
- Increases water and urea reabsoprtion
- Creates maximally concentrated urine
15
Q
What is the treatment for recurrent Ca stones?
A
Saturation with citrate
Citrate binds free (ionized) calcium, preventing precipitation and facilitating excretion.
16
Q
What pathological process differentiates lower UTIs from pyelonephritis?
A
Anatomical or functional vesicoureteral reflux.
Urine flows back into the kidney
17
Q
What area of the nephron is impermeable to water regardless of serum ADH levels?
A
The ascending loop of Henle.
Reabsorption of electrolytes by the NA/K/2Cl transporter occurs in the TAL and contributes to the corticomedullary gradient.
18
Q
What type of kidney stone cannot be seen on xray?
A
Uric acid stones
- Radiolucent
Found in patients with:
- Gout
- Myeloproliferative disorders
- High protein diets
- Low fluid intake
- Lesch-Nyhan
19
Q
How does spironolactone affect H secretion?
A
Spironolactone is an aldo receptor inhibitor
- Aldo increases Na absorption, and thus H secretion from a-intercalated cells in the CD
- No aldo = no Na absorption, no H (or K) secretion
20
Q
Where in the kidney is the concentration of PAH the lowest?
A
Bowman’s Space
PAH is freely filtered an not reabsorbed, so the concentration will be lowest at the start (Bowman’s) and highest at the end of the nephron.
21
Q
How does losartan affect levels of:
- Renin
- ATI
- ATII
- Aldo
- Braydkinin
A
Losartan is an ARB.
- Renin: increase
- ATI: increase
- ATII: increase
- Aldo: decrease
- Bradykinin: no change
22
Q
How do you avoid acyclovir nephrotoxicity?
A
When acyclovir conc. in CD exceeds solubility, get crystallization, crystalluria, renal tubular damage.
Avoid with:
- Aggressive IV hydration
- Lower dosage
- Slow rate of IV infusion
23
Q
How does efferent arteriolar constriction affect GFR and FF?
A
GFR: increases
- Efferent constriction increases Ph glomerulus
- This increases GFR
- GFR depends on difference between hdyrostatic and oncotic pressures between glomerular capillaries and Bowman’s space
FF: increases
- FF = GFR/RPF
- Renal Plasma Flow is reduced by efferent constriction
- More GFR and less RPF = greater FF
24
Q
What is the most likely source of obstruction in fetal hydronephros?
A
Ureteropelvic Jx.
The ureteropelvic jx is the jx between the kidney and ureter.
- Last segment of the fetal ureter to canalize
- Most common site of obstruction
25
Calculate FF, given:
- RBF = 1
- GFR = .1
- Hct = .5
FF = GFR/RPF
```
RPF = RBF * (1-Hct)
RPF = (1)* (1-.5) = .5
```
FF = .1/.5 = .2
26
A diuretic causes increased serum Ca. What kind of drug is it and where does it work?
Thiazide diuretic.
- Distal Convoluted Tubule
- Works to block the Na/Cl symporter (apical)
- Less Na in means apically means more in basolaterally via Na/Ca exchanger
- More Ca back into serum
27
Baby is born with bilateral renal agenesis. What is the most likely cause of death?
Lung immaturity.
Swallowed amniotic fluid contributes to lung maturity in fetus.
Renal agenesis results in Potter's:
- Renal aplasia
- Oligohydramnios
- Characteristic facies
- Lung hypoplasia
28
How much K is reabsorbed at each part of the nephron?
Bowman's: freely filtered (100% remains)
PT: 65% reabsorbed (35% remains)
TAL: 25-30% reabsorbed (10% remains)
CD: 100+% secreted by principal cells (110%)
29
What is first dose hypotension?
Adverse effect when initiating ACE inhibitors. Risk factors:
- Hypovolemia secondary to diuretics
- Hyponatremia
- High renin or aldo
- Renal impairment
- Heart failure
30
Biopsy shows narrowed renal arterioles with arteriolar walls homogenously thickened and stained pink with H&E.
What is the underlying chronic condition?
This is hyaline arteriosclerosis from:
- Diabetes, or,
- NON malignant HTN
31
What kind of arteriosclerosis does malignant HTN produce?
Hyperplastic arteriosclerosis
| - Onion skin concentric thickening
32
Where in the nephron does most water reabsorption occur?
Proximal tubule
33
Calculate RBF given:
- Hct 50%
- Urine flow 1 ml/min
- PAH = 100 in urine, .2 in serum
RBF = PAH clearance/ (1-Hct)
PAH clearance = (urine PAH x urine flow rate)/ plasma PAH
= [(100 x 1)/.2} = 500
PAH = 500/ (1-.5) = 1000 ml/min
34
What is the most common cause of kidney stones?
Idiopathic hypercalicuria.
Other causes:
- Hyperoxaluria
- Hyperuricosuria
- Low urine vol
- Hypocitraturia
35
What type of immune response mediates hyperacute (minutes to hours) transplant rejection?
Preformed antibodies against graft in recipient's circulation
- Gross mottling and cyanosis
- Arterial fibrinoid necrosis & capillary thrombotic occlusion
36
What type of immune response mediates acute organ rejection?
Humoral response: Cd4 deposition, neutrophilic infiltrate, necrotizing vasculitis
Cellular: activation of naive immune cells
37
What type of immune response mediates chronic (months to years) organ rejection after transplant?
Chronic, low grade immune response refractory to immunosuppressants
- Vascular wall thickening and luminal narrowing
- Interstitial fibrosis
38
What type of glomerulonephritis is associated with antibodies against the PLA2R (phospholipase A2 receptor) found on podocytes?
Idiopathic membranous nephropathy
39
What type of immune response is associated with each stage of organ rejection?
Hyperacute
- Preformed host antibodies attack organ
Acute
- T cell sensitization against donor MHC (HLA) antigens
Chronic
- Long term, low grade immun response
40
How does the liver respond to proteinuria in minimal change disease?
Makes more lipoproteins because of the loss in albumin.
Increase in serum lipoproteins is followed by lipiduria.
41
The exchange of inductive signals between the ureteric bud and the metanephric blastema drives the diffierentiation of structures that form the mature kidney.
What does the ureteric bud give rise to?
- Collecting tubules & ducts
- Major & minor calyces
- Renal pelvis
- Ureters
42
The exchange of inductive signals between the ureteric bud and the metanephric blastema drives the diffierentiation of structures that form the mature kidney.
What does the metanephric blastema give rise to?
- Glomeruli
- Bowman's space
- Proximal tubules
- Loop of Henle
- Distal convoluted tubules
43
Which diuretic (part of a multi-drug treatment regimen) has been shown to improve overall survival in CHF?
Spironolactone, through inhibition of the neurohormonal effects of aldo, particularly on the heart.
It's possible the diuretic effects contributed little to the overall benefit.
44
How does Lithium cause nephrotox?
Antagonizes ADH in principal cells of the CD.
45
What is the pathogenesis of overflow incontinence?
Impaired detrusor contractility or bladder obstruction.
Diabetics with autonomic neuropathy affecting the detrusor muscle innervation >
Incomplete emptying (cannot sense full bladder) >
Overflow
46
Unintentional ureteral ligation is a risk of surgery to remove cervical cancer due to manipulation of the uterine artery.
What is a possible adverse result?
Hydronephrosis
- Kidney makes urine but it doesn't drain to the bladder
- Presents as palpable mass (kidney) on deep abdominal palpation
47
What are causes of hyperosmotic volume contraction?
DI or profuse sweating
increased Osm, decreased ICF, decreased ECF
48
Lipophilic drugs are eliminated (renally or hepatically)...
Hepatically
- Cross renal tubular membrane and re-enter tissue
- Enter hepatocytes and excreted through bile
49
No tubular reabsorption or secretion
| Filtered amount = excreted amount
Inulin and Mannitol
50
Net tubular reabsorption
| Filtered amount >> excreted amount
Glucose, Na, Urea
51
Net tubular secretion
| Filtered amount
PAH and Creatinine
52
Used to measure GFR
Inulin
53
Used to measure RPF
PAH
54
Horseshoe kidneys get trapped under what vessel?
IMA
55
NSAIDs cause injury to what parts of the kidney?
Papillary or Interstitial Necrosis (not glomerular or vascular)
56
Type of urinary incontinence:
Loss of urethral support
Leaking w laugh, cough, sneeze, lift
Stress incontinence
57
Type of urinary incontinence:
Detrusor overactivity
Sudden urge to empty bladder
Urge incontinence
58
Type of urinary incontinence:
Impaired detrusor contractility
Bladder outlet obstruction
Involuntary dribbling, incomplete emptying
Overflow incontinence
59
How does efferent constriction change:
- GFR
- RPF
- FF
Increases GFR
Decreases RPF
Increases FF (= GFR/RPF)
60
The Urachus is a remnant of what fetal structure?
Allantois, which connects bladder to yolk sac
61
Urine discharge from umbilicus in neonate indicates:
Persistent allantois (urachus)
62
Meconium discharge from umbilicus in neonate indicates:
Persistent yolk sac
63
Which rib is over the kidney?
12
64
Ethylene glycol produces what kind of crystals?
Oxalate crystals int he renal tubules + damage
| Anion gap acidosis, increased osmolar gap, crystals in urine
65
1st result of salicylate tox
Resp alk
66
2nd result of salicylate tox
Metab acid
67
Symptoms of salicylate tox:
Fever, tinnitus, tachypnea
68
Membranous Glomerulonephropathy is associated with what systemic diseases?
Diabetes
Lupus
Solid tumors
69
Membranous Glomerulonephropathy is associated with what drugs?
Gold
| Penicillamine
70
Membranous Glomerulopnephropathy is associated wtih what infetions?
Hep B, C
Malaria
Syph
71
What does Membranous Glomerulonephropathy look like on LM?
Uniform thickening of capillary wall of glomerulus
| Without increase in cellularity
72
What does Membranous Glomerulonephropathy look like on EM?
Spike and dome: IgG + C3
73
Kimmelstiel Wilson nodules indicate:
Diabetic Nephropathy
74
What is the MOA of sildelafil and tadalafil?
Phosphodiesterase inhibitors that promote erection by relaxing venous smooth muscle in corpora cavernosa
75
What is the most important prognostic factor in PSGN?
Age! Kids recover, but adults may progress to RPGN
76
How does ureteral constriction affect FF?
Decreased FF
Increased P in Bowman's Space >
Decreased GFR >
FF = GFR/RPF
77
What is the differential for metabolic alkalosis? (What is the Cl- in each?)
1. Vomiting/nasogastric suction (low Cl-)
2. Thiazide/loop diuretic (high Cl- while using, low after)
3. Hyperaldo (high Cl-)
78
What test do you order to differentiate types of metabolic alkalosis?
Urine Cl-
79
What are side effects of ACE-I?
Increased Ck
Hyperkalemia
COUGH
Rare: angioedema
80
What are the two embryological origins of the kidney?
Metanephric Mesoderm
| Ureteric Bud
81
What structures derive from the Ureteric Bud?
Collecting ducts
Minor/major calyces
Renal pelvis
Ureters
82
What structures derive from the Metanephric Mesoderm?
```
Glomeruli
Bowman's space
PT
Loop of Henle
DCT
```
83
Necrotizing vasculitis of upper and lower respiratory tract
Nasal ulcers, sinusitis, hemoptysis, RPGN
cANCA (MPO)
Wegner's
84
What is osteitis fibrosa cystica?
Result of end stage renal disease, in which you have secondary hyperparathyroidism that results in increased bone turnover and osteodystrophy
85
How does vasopressin affect urea?
Vasopressin increases permeability to water AND UREA at the luminal membrane of the CD
- Increased reabsorption, decreased clearance from plasma
86
Palpable purpura preceded by URT infection
Henoch Schonlein Purpura
87
Henoch Schonlein Purpura is associated with what immunoglobulin?
IgA
88
What systems does Henoch Schonlein Purpura affect?
GI: intermittent severe ab pain, bloody stool, diarrhea
Kidney: IgA nephropathy + mesangial proliferation
Joints: migratory arthralgia, arthritis in large joints
89
What is the formula for RBF?
RBF = PAH clearance/(1-Hct)
PAH clearance = (urine flow rate x urine [PAH]/) plasma [PAH]
90
What renal syndrome can present a few day after a URI?
IgA nephropathy
91
What renal syndrome can present a few weeks after a URI?
PSGN
92
What lysosomal storage disease can result in renal failure?
Fabry
93
What enzyme is deficient in Fabry's?
a-galactosidase A, leading to buildup of ceramide trihexoside
94
Lab values in DKA: (increase/decrease)
- Ketones
- Glucose
- Na
- K
Hyperketonemia
Hyperglycemia
HYPOnatremia
HYPERkalemia
95
Collapsing glomerulonephropathy is associated with what nephrotic syndrome?
FSGS
Affected segments show BM collapse, hyalinosis, increased matrix
96
Renal failure + toe gangrene + livedo reticularis after invasive vascular procedure indicates what kidney pathology?
Atherothrombolic renal disease
97
What is found in the kidney in atheroembolic kidney disease?
Cholesterol emboli obstructing renal arterioles (not intrinsic to kidney)
98
What adverse effect can occur on the first dose of ACE-I?
Hypotension
| - Renal impairment is a risk factor
99
What are 3 types of RPGN?
1. Goodpasture's
2. PSGN
3. Pauci-immune (ANCA)
All are crescentric!
100
Fever + maculopapular rash + eosinophilia + renal failure 1-3 weeks post rx with b-lactams indicates:
Acute Interstitial Nephrosis
101
Type of nephropathy associated wtih IgG4 Abs to PLA2 receptor
Idiopathic Membranous Nephropathy
102
Lab findings with Thiazides:
HYPER
- Calcemia
- Uricemia
- Glycemia
- Lipidemia
HYPO
- kalemia
- tension
103
Dehydration and:
- GFR
- RPF
- FF
GFR decreases a little (Because RAAS maintains some)
RPF decreases a lot
FF increases
104
What type of crystal composes a staghorn calculus?
Ammonium Magnesium Phosphate (struvite)
105
What bugs cause staghorn calculi?
Protease (+)
Proteus
Klebsiella
Staph aureus
106
Congenital renal anomaly that causes dilation of renal pelvis and minimal functionality
Congenital Ureteral Obstruction
- Increased risk of UTI
107
How does BPH cause renal failure?
Pressure backup into Bowman's space decreases GFR
108
Name that vasculitis:
```
Necrotizing granulomas
Sinusitis +/- perforated nasal septum
Hemoptysis, cough
Hematuria, RBCs
cANCA
```
Wegner's
109
Name that vasculitis:
```
Necrotizing granulomas
Sinusitis with eos
Asthma
Hematuria, RBCs
Peripheral neuropathy
pANCA
```
Churg-Strauss (EGPA)
110
Hemoptysis, cough
Hematuria, RBCs
pANCA
MPA
111
From where in the kidney does RCC originate?
PT
| - Clear cells
112
From where in the kidney does renal oncocytoma originate?
CD
| - Large, well diff cell with mitoses
113
From where in the kidney does a papillary tumor originate?
Renal pelvis
| - Urothelium + thin fibrotic stalk
114
Gross hematuria + acute colicky flank pain + passage of tissue fragments in urine:
Papillary Necrosis
115
How does mannitol cause pulmonary edema?
Osmotic diuresis >
Increased hydrostatic P in vasculature >
3rd spacing of fluid
116
In what condition is mannitol contraindicated?
CHF or previously established pulmonary edema
117
Densely immunostaining, protein containing cells adjacent to the glomerulus
J-G Apparatus
| - Renin synth, storage, secretion
118
What is IVC syndrome?
Compression of the IVC that may be acute or gradual (Ex. renal tumor)
Colateral compensation by abdominal wall vessels
Edema
119
Classic triad of flank pain, flank mass, and hematuria indicates:
Renal Cell Carcinoma
