Renal

Question 1

What is another name for post-streptococcal glomerulonephritis?

Answer 1

Acute proliferative glomerulonephritis

Question 2

How can one determine if pleural effusion in a pt is related to co-morbid nephrotic syndrome or an infection?

Answer 2

Nephrotic syndrome → transudate

Infection → exudate (elevated protein, LDH

Question 3

Excess production of aldosterone (i.e. Conn’s syndrome) leads to what GI and urinary findings?

Answer 3

constipation, polyuria

Question 4

What is the pronephros?

Answer 4

A transient collection of cells that disappears during the fourth week of development. It does NOT form the permanent kidney.

Question 5

In a patient with a severe UTI and bacteremia, what empiric therapy should be started? What kind of drugs should not be used?

Answer 5

IV ampicillin and gentamicin, ciprofloxacin, olfloxacin, or ceftriaxone (i.e. bactericidal agents that kill gram-negatives); do not use bacteriostatic agents such as tetracycline, erythromycin, and nitrofurantoin in severe cases

Question 6

What is a normal range for urine potassium? A high value can indicate abuse of what drug?

Answer 6

25-125 mEq/d; diuretics (e.g. an athlete trying to lose weight)

Question 7

What is an oncocytoma?

Answer 7

Oncocytoma is an uncommon epithelial tumor thought to arise from the intercalated cells of the collecting tubules.

Gross: Well-encapsulated tumors with a homogenous, tan or mahogany brown cut surface

Histologic: large eosinophilic cells w/ small round nuclei and prominent mitochondria

Question 8

What is bumetadine?

Answer 8

A loop diuretic

Question 9

What type of cells predominantly make up the DCT and what is one area of exception?

Answer 9

Most of the distal convoluted tubules is lined by simple cuboidal epithelium with a modest apical brush border of microvilli. The macula densa is a discoid patch of tall columnar cells in the wall of the distal convoluted tubule.

Question 10

What is the equation for plasma osmolality?

Answer 10

(total body osmoles - urine osmoles) / (TBW - urine volume)

Question 11

How do you calculate TBW?

Answer 11

weight (kg) x % of body composed of H2O (~60%)

Question 12

How do you calculate total body osmoles?

Answer 12

plasma osmolarity x TBW

Question 13

What is the most common form of the nephrotic syndrome?

Answer 13

FSGS (Kaplan)

Membranous (Firecracker)

Question 14

In organisms that colonize the urinary tract causing UTI, what is the most important pathogenic factor?

Answer 14

P-pilli (pyelonephritis-associated pilli): mediates attachment to urinary tract mucosa

Question 15

What category of drug is indomethacin? As such, what is its effect on the kidney?

Answer 15

NSAID - decreases prostaglandin synthesis → afferent arteriole constriction

Question 16

What effect do ACE inhibitors have in the treatment of patients with the nephrotic syndrome?

Answer 16

Improved symptoms, ↓ protein and lipid excretion, but ↑ plasma K+

Question 17

What class of drug is enalapril?

Answer 17

ACE inhibitor

Question 18

How can ECF volume be estimated?

Answer 18

Inulin: (amount administered - excreted)/ plasma [inulin]

Question 19

What effect can ACE inhibitors have in patients at risk for acute renal failure?

Answer 19

↓ ATII → ↓ efferent arteriole constriction → ↓ GFR → ↑ serum creatinine → ARF (especially if co-morbid with vascular dz s.a. athero)

Question 20

What effect does sickle cell disease have on the kidney?

Answer 20

sickle cell crisis affecting vasa recta of renal medulla → ischemia → patchy papillary necrosis

Question 21

The antibodies in Goodpasture syndrome can also affect which part of the eye?

Answer 21

lens (contains Type IV collagen)

Question 22

How does Wilms tumor present histologically?

Answer 22

Islands of stromal or epithelial cells which may organize into recognizable glomerular or tubular structures; may also contain muscle, bone, cartilage, fat, and fibrous tissue.

Question 23

As the plasma concentration of a secreted substance increases, how is clearance of the substance affected?

Answer 23

Clearance is maintained until saturation of secretory transporters leads to a decrease in clearance (clearance = urinary excretion/plasma conc. & both rise proportionally)

Question 24

What is tolterodine and what is it indicated for?

Answer 24

competitive muscarinic receptor antagonist used to treat urinary incontinence, urgency, and frequency

Question 25

What is a cause of hypernatremia (↑ osm) with a continued ADH-refractory polyuria?

Answer 25

T2DM

Question 26

What is the equation for anion gap?

Answer 26

[Na+] - ([Cl-] + [HCO3-])

Question 27

How can GFR be calculated from lab measurements of creatinine?

Answer 27

For creatinine, excretion rate = filtration rate (roughly)
Excretion rate = Ucr x V
Filtration rate = Pcr x GFR
GFR = Ucr x V / Pcr

Question 28

What dietary recommendations should be made for a patient with chronic renal failure?

Answer 28

High carb, moderate fat, low protein, low fluid intake

Question 29

Which drug class decreases Na+ reabsorption while decreasing K+ excretion?

Answer 29

ACE inhibitors through ↓ ATII → ↓ aldosterone and corresponding ↑K+

Question 30

In a patient with renal insufficiency, does FENa+ ↑ or ↓ ? How about K+?

Answer 30

It will initially increase to maintain normal plasma levels since GFR is ↓ until the patient becomes substantially oliguric

Question 31

Where is most water reabsorbed in the kidney?

Answer 31

60% in the proximal tubule

Question 32

What is the main side effect of cyclosporin?

Answer 32

nephrotoxicity – the mechanism is believed to include intense vasoconstriction → ↓ GFR; affects ppl >50 y.o. and transplant patients (6-8 wks post)

Question 33

What pathology does DIC cause in the kidney?

Answer 33

diffuse cortical necrosis

Question 34

Do loop diuretics lead to ↑ NaCl delivery to the macula densa? What is the result?

Answer 34

Yes, but the MD has the same NKCC transporter that furosemide acts on, so less NaCl is detected → ↑ renin secretion, efferent arteriole constriction, ↑ GFR

Question 35

Is mannitol contraindicated in oliguria?

Answer 35

No, it is contraindicated in aneuria

Question 36

Which diuretic class of drugs is contraindicated in crush injury patients with renal failure?

Answer 36

potassium sparing, s.a. spinonolactone and eplernone → hyperkalemia → arrhthmias → possible death

Question 37

What would happen to bicarb levels immediately after 2 minutes of not breathing?

Answer 37

slightly increase

Question 38

Is E. coli lactose fermenting?

Answer 38

yes

Question 39

What gram negative rod that causes UTIs is lactose non-fermenting?

Answer 39

P. aeruginosa

Question 40

How do you calculate renal plasma flow?

Answer 40

RPF = PAH clearance = urine [PAH]*urine flow rate / plasma [PAH]

Question 41

How do you calculate renal blood flow?

Answer 41

RBF = PAH clearance / 1 - hematocrit

Question 42

What are the 2 titratable acids that can be found in the urine in metabolic acidosis (e.g. DKA)?

Answer 42

NH4+, H2PO4-

Question 43

How body fluid volume affected in SIADH?

Answer 43

It transiently increases → ↑ ANP → ↑ sodium excretion → normal body fluid volume
(euvolemic hyponatremia)