Deck IX

Question 1

What is the typical clinical presentation of a patient with IgA nephropathy (or Berger disease)?

Answer 1

Typically affects children and young adults- patients usually present with painless hematuria 2-3 days following an upper respiratory tract infection. Hematuria typically lasts a few days and then returns sporadically every few months.

Question 2

What is seen on immunofluorescent microscopy in a patient with IgA nephropathy?

Answer 2

Prominent IgA deposits in the mesangium which appear like electron dense material.

Question 3

What is IgA nephropathy classified as when it is accompanied by extrarenal symptoms (i.e. abdominal pain, purpuric skin lesions, etc)?

Answer 3

Henoch-Schonlein purpura.

Question 4

What are the typical findings on light microscopy for a patient with poststreptococcal glomeurlonephritis?

Answer 4

Hypercellular glomeruli

Question 5

What presents on urinalysis of a patient with poststreptococcal glomeurlonephritis?

Answer 5

Hematuria, proteinuria, urine RBC casts

Question 6

What laboratory findings are consistent with a diagnosis of poststreptococcal glomeurlonephritis?

Answer 6

Elevated titers of anti-streptococcal antibodies (antistreptolysin O, anti DNase B, anti-cationic proteinase) cryoglobulins, and low C3 concentration.

Question 7

What is the function of Calcineurin?

Answer 7

Essential protein in the activation of IL-2 which promotes growth and differentiation of T cells.

Question 8

What is the mechanism of action of cyclosporine and tacrolimus in immunosuppression?

Answer 8

Inhibition of calcineurin activation.

Question 9

Where is renin synthesized?

Answer 9

Modified smooth muscle (juxtaglomerular) cells of the afferent glomerular arterioles.

Question 10

Renal toxicity associated with amphotericin B requires monitoring for what deficiencies?

Answer 10

Severe hypokalemia and hypomagnesemia

Question 11

Name three factors that promote salt crystalization in urine and two factors that reduce it.

Answer 11

Increased concentrations of calcium, phosphate, oxalate promote stone crystallization; increased citrate and high fluid intake help prevent calculi formation.

Question 12

Addition of what drug to a multidrug regimen to treat class III and IV heart failure patients has been shown to significantly reduce morbidity and mortality?

Answer 12

Spironolactone.

Question 13

What is Primase?

Answer 13

A DNA dependent RNA polymerase that incorporates short RNA primers into replicating DNA.

Question 14

ARBs generate what changes to circulating levels of renin, angiotensin I, angiotensin II, bradykinin, and aldosterone?

Answer 14

Increase renin, angiotensin I, angiotensin II (due to diminished negative feedback mechanisms); decreased aldosterone; no change in bradykinin.

Question 15

In renal dysfunction, hypokalemia and hypomagnesemia reflect what pathology to the kidneys?

Answer 15

Increased distal tubular membrane permeability.

Question 16

What action do ACE inhibitors have on renal arterioles?

Answer 16

ACE inhibitors promote efferent arteriolar dilation causing GFR reductions.

Question 17

What action does angiotensin II have on renal arterioles?

Answer 17

It preferentially constricts efferent arterioles.

Question 18

How do you calculate filtration fraction?

Answer 18

FF= GFR/RPF; GFR can be estimated by creatinine/ inulin clearance; RPF can be measured with PAH clearance.

Question 19

In what forms is acid excreted in the urine?

Answer 19

NH4+, H2PO4- and free H+.

Question 20

Under what conditions does a patient with metabolic acidosis likely also have a superimposed degree of respiratory acidosis and respiratory failure?

Answer 20

When the steady state PaCO2 is higher than what is given in Winter’s formula (PaCO2 = [1.5*HCO3-] +8 +/- 2)

Question 21

How does ureteral constriction or obstruction affect GFR and glomerular filtration fraction?

Answer 21

Acutely decreases both GFR and glomerular filtration fraction due the increased hydrostatic pressure proximal to the constriction.

Question 22

What is the difference between PAH and inulin in measuring GFR and RPF?

Answer 22

Inulin is freely filtered and is neither reabsorbed nor secreted by the renal tubules; PAH is freely filtered but is also secreted into the urine by an energy dependent organic acid transporter in the proximal tubule; PAH excreted is thus greater than the filtered load.

Question 23

Which hormones prevent lactation during pregnancy?

Answer 23

High levels of estrogen and progesterone.

Question 24

Where are neurophysins produced and released?

Answer 24

Produced in the paraventricular and supraoptic nuclei of the hypothalamus and are released from axon terminals in the posterior pituitary gland.

Question 25

What are neurophysins?

Answer 25

Proteins involved in the posttranslational processing of oxytocin and vasopressin.

Question 26

What are two possible treatments for paroxysmal supraventricular tachycardia?

Answer 26

Carotid sinus massage, valsalva maneuver

Question 27

How does carotid sinus massage alleviate symptoms of paroxysmal supraventricular tachycardia?

Answer 27

By increasing cardiac parasympathetic tone, it slows the heart rate by slowing conduction through the AV node. Slowed conduction in the AV node abolishes re-entrant circuits causing PSVT.

Question 28

What muscle feedback system maintains muscle force? What system maintains muscle length?

Answer 28

Force is monitored by the Golgi tendon system; the muscle spindle system maintains muscle length.

Question 29

To what stimuli are Golgi Tendon Organs sensitive?

Answer 29

Increases in muscle tension, not sensitive to passive stretch.

Question 30

How is Renal blood flow (RBF) calculated?

Answer 30

RBF= (PAH clearance)/ (1-Hematocrit)