Rx_2.15 (Renal) Flashcards Preview

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Flashcards in Rx_2.15 (Renal) Deck (14)
1

Strongest risk factor for bladder cancer (transitional cell carcinoma)

  • **exposure to aniline dyes
    • = synthetic dyes used in textile mills
  • smoking is a risk factor in extended exposures

2

Defect in transporter of neutral amino acids ==>

  • Dx = "Hartnup's dz"
  • defective transporter @ small intestine & kidney
    • ==> wasting of neutral amino acids (except proline)
  • ==> sx of niacin deficiency (pellagra) = neurologic impairment and dermatitis
    • tryptophan (neurtral) + B6 can make niacin

3

Neutral amino acids

  • tryptophan
  • phenylalanine
  • glycine
  • alanine
  • valine
  • isoleucine
  • leucine
  • methionine
  • proline

4

Common early finding of APCKD

  • HTN 
    • avg age @ onset = 30
  • + family hx of kidney problems

5

Common drug used to tx transplant patients + MOA/SE

  • cyclosporine
  • MOA:
    • binds cyclophillin ==l calcineurin ==> blocks production of IL-2 and receptor
    • IL-2 = necc. for diffentiation of T lymphocytes and clonal expansion of antigen-selected cytotoxic T lymphocytes
  • SE
    • nephrotoxic effects

6

Renal biopsy in diabetic nephropathy

  • loss of heparan sulfate moieties that form negatively charged filtration barrier ==> increased filatration of serum proteins into urine
  • Kimmelstiel-Wilson nodules
    • eosinophillic, periodic acid-Schiff-positive
  • expansion of mesangium on light microscopy
    • nonspecifc linear deposition of albumin, IgG, complement
    • no immune deposits on EM

7

Renal biopsy: diffuse granular IgG and C3 on IF ==> dx?

  • immune complex glomerulonephritis
    • e.g. PSGN

8

Renal biopsy: positive anti-light chain antibody staining of IF ==> dx?

  • multiple myeloma or lymphoproliferative disorders
  • light chains precipitate in renal tubules ==> acute renal failure

9

Renal biopsy: positive fibril staining w/Congo red ==> dx?

  • renal amyloidosis due to deposition of amyloid A
    • beta-pleated sheets of serm amyloid A
  • associated w/Rheumatoid arthritis

10

PTH actions (general) + @ kidney

  • PTH ==> protection of serum ionized [Ca2+]
    • works to increase Ca levels and decreased phosphate levels
  • ==> bone resorption ==> calcium and phosphate into ECF
  • @ kidney
    • ==> decreased phosphate reabsorption
    • stimulates 1-a-hydroxylase activity ==> produces 1,25-OH vit D (from 25-OH vit D)
      • ==> increased Ca2+ @ gut

11

Celecoxib: MOA

  • COX-inhibitor ==> decreased PG production

12

Common cause of respiratory acidosis + acute physiologic response

  • Apnea ==> increased pCO2 ==> respiratory acidosis
  • Carbonic anhydrase: CO2 + H2O ==> H2CO3 ==> H+ + HCO3-
  • physiologic response = buffering
    • H+ enters cells and binds to intracellular proteins
    • hemoglobin
    • bone matrix

13

Chronic compensation for respiratory acidosis

  • enhanced renal secretion of hydrogen ions
  • takes aprox. 6-12 hours to set in and 3-4 days to peak
  • @ chronic acidotic pts. (e.g. COPD):
    • produce carbonic acid
      • retain bicarb and excrete H
    • exchange Na for H
    • secreting NH3 into the urine to trap H ion there in form of the ammonium ion

14

Common complication of EHEC

  • EHEC ==> (usually) self-limiting, bloody diarrhea that lasts 5-10 days
  • hemolytic uremic syndrome
    • anemia
    • thrombocytopenia
    • acute renal failure
    • **most common cause of acute renal failure in children

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