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Flashcards in Renal Deck (9)
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1
Q

Chronic renal artery stenosis causing significant renal hypoperfusion will lead to hyperplasia of what structures?

A

Juxtaglomerular cells (modified smooth m. cells) of the afferent glomerular arteriole

2
Q

How to calculate the total filtration rate for a substance and the excretion rate?

A
  • F.R. = (Inulin clearance aka GFR) x (Plasma concentration of substance)
  • E.R = (Filtration Rate) - (Tubular Reabsorption rate of Substance)
3
Q

CKD leads to hyperphosphatemia which can induce hypocalcemia via what 2 mechanisms?

A
  • Phosphate binds free Ca2+ and precipitates in soft tissues
  • Triggers release of FGF-23 (bone), inhibits renal expression of 1-alpha hydroxylase, reducing production of calcitriol and intestinal Ca2+ absorption
4
Q

What is the most common cause of unilateral fetal hydronephrosis?

A

Inadequate canalization of the ureteropelvic junction

5
Q

Which parts of the kidney arise from the ureteric bud?

A
  • Collecting system of the kidney: including collecting tubules and ducts
  • Major and minor calyces
  • Renal pelvis
  • Ureters
6
Q

Which parts of the kidney arise from the metanephric blastema?

A
  • Glomeruli
  • Bowman’s space
  • Proximal tubules
  • Loop of Henle
  • Distal convoluted tubules
7
Q

What are the 2 most metabolically active segments of the nephron which are particularly vulnerable to acute tubular necrosis as a result of ischemia?

A
  • Terminal (straight) portion of proximal tubule
  • Thick ascending limb of the loop of Henle
8
Q

What is the effect of natriuretic peptides (ANP and BNP) on the kidney?

A
  • Promote afferent dilation and efferent constriction which increases GFR
  • Leads to increased Na+ and H2O excretion
9
Q

Which renal disease presents with painless hematuria within 5-7 days of a URI and then subsides temporarily, returning ever few months or with another URI?

A
  • IgA nephropathy (Berger disease)
  • Biopsy showing: mesangial hypercellularity and mesangial IgA deposition