Lecture 8: CIS

Question 1

What 3 things cause high urine Na+?

Answer 1

1) Drugs
2) AKI
3) Renal disease

Question 2

What 2 things cause low urine Na+?

Answer 2

1) Hypovolemia

2) Nephrosis (Cirrhosis, CHF)

Question 3

What 3 things cause high urine K+?

Answer 3

1) Drugs
2) Vomiting
3) Diarrhea

Question 4

What causes low urine K+?

Answer 4

Usually renal disease with hormonal implications

Question 5

What does a GAP of 0 and >0 indicate?

Answer 5

0 = nonrenal metabolic acidosis

> 0 = renal cause

Question 6

Common causes of acute tubular necrosis?

Answer 6

Hypotension and sepsis

• Renal ischemia
• Nephrotoxins
• Major surgery
• Hypoperfusion
• Endogenous toxins (MM, tumor lysis)
• BURNS!

Question 7

What often precedes progression to renal failure in acute tubular necrosis?

Answer 7

Azotemia

Question 8

What is acute interstitial nephritis?

Answer 8

Decline in renal function secondary to renal lesion = inflammatory rxn within the renal interstitium

Question 9

Acute interstitial nephritis is often induced by what 3 things?

Answer 9

1) Drugs - antibiotics responsible for 30-50%
2) Autoimmune disorders: lupus, scleroderma
3) Infections: streptococcal, legionella

Question 10

What disease requires an extensive workup with lab, imaging, and renal biopsy?

Answer 10

Acute Glomerulonephritis

Question 11

What are some of the pathological findings associated with Acute Glomerulonephritis?

Answer 11

• Hematuria and Proteinuria
• Renal insufficiency
• HTN
• Edema: nephrosis
• Hyper-coagulability: thrombosis and membranous neuropathy

Question 12

Patient with enlarged prostate, urine backing up, and low BUN:Creatinine is likely suffering from what kind of AKI?

Answer 12

Post-renal!

Question 13

If BUN:creatinine is <20 is likely what kind of AKI?

Answer 13

Intrarenal

Question 14

AKI is defined as what change in serum creatinine?

Answer 14

> 0.3 mg/dL within 48 hours or >1.5 x baseline presumed to have occurred within the prior 7 days

Question 15

What is the most used criteria for staging AKI?

Answer 15

KDIGO - Kidney disease: improving global outcomes

Question 16

What is the criteria for the 5 stages of kidney disease based on GFR?

Answer 16

Stage 1: >90 normal or high
Stage 2: 60-89 mild decrease
Stage 3: 30-59 moderately decreased
Stage 4: 15-29 severe
Stage 5: <14 = kidney failure, add if on RRT or not

Question 17

20:1 or greater in hypovolemia not complicated by renal ischemia indicates?

Answer 17

• Proximal tubule reabsorption
• Hypovolemia causes increased Na and H20 redsorption and urea reabsorption
• Thus, urea excretion decreases elevating the BUN
• Pre-renal azotemia

Question 18

What is occurring to reabsorption and excretion in <20:1?

Answer 18

Both decreased

Question 19

What is anion gap calculation

Answer 19

= (Na+) - (Cl + HCO3)