Renal15

Question 1

T/F - In normal nephron, BUN is reabsorbed, but creatine is not.

Answer 1

True

Question 2

Definition of Acute Renal Failure.

Answer 2

Abrupt decline in renal function w/:
-HIGH creatinine
-HIGH BUN
over a period of several days

Question 3

Types os Acute Renal Failure.

Answer 3

Prerenal azotemia
Intrinsic renal failure
Postrenal azotemia

Question 4

Acute Renal Failure:

-Prerenal

Answer 4

• Result of LOW RBF (e.g., hypotension)
• LOW GFR
• Na+/H20 and urea retained by kidney in an attempt to conserve volume -> HIGH BUN/Cr ratio

Question 5

Acute Renal Failure:

-Intrinsic

Answer 5

• Acute tubular necrosis or ischemia/toxins
• Patchy necrosis leads to debris obstructing tubuel and fluid backflow across necrotic tubule
• LOW GFR
• Urine has epithelial/grandular casts
• BUN reabsorption is impaired -> LOW BUN/Cr ratio

Question 6

Acute Renal Failure:

-Postrenal

Answer 6

• Ouflow obstruction (stones, BPH, neoplasia, congenital anomalies)
• Develops ONLY with BILATERAL obstruction

Question 7

Acute Renal Failure:

-Urine osmolality

Answer 7

Prerenal: >500
Intrinsic: <350

Question 8

Acute Renal Failure:

-Urine Na

Answer 8

Prerenal: 40
Postrenal: >40

Question 9

Acute Renal Failure:

-Fe(Na)

Answer 9

Prerenal: 2%
Postrenal: >2%

Question 10

Acute Renal Failure:

-Serum BUN/Cr ratio

Answer 10

Prerenal: >20
Intrinsic: <15

Question 11

Consequences of Renal Failure

Answer 11

• Na+/H20 retention (CHF, pulmonary edema, HTN)
• Hyperkalemia
• Metabolic acidosis
• Uremia
• Anemia (failure of EPO production)
• Renal osteodystrophy
• Dyslipidemia (HIGH TGs)
• Growth retardation and developmental delay

Question 12

What is the clinical manifestation of Uremia?

Answer 12

HIGH BUN & HIGH creatinine

• Nausea & anorexia
• Pericarditis
• Asterizis
• Encephalopathy
• Platelet dysfunction

Question 13

Renal Osteodystrophy.

Answer 13

• Failure of Vit. D hydroxylation
• Hypocalcemia
• Hyperphosphatemia
• 2˚ hyperparathyroidism

Causes subperiosteal thinning of bones