2 Diagnosis of acute kidney injury

Question 1

Definition of acute kidney injury

Answer 1

Rapidly decreased GFR, over just hours or days.
and/or
Oliguria or anuria.

• Increase in SeCr by at least 0.3 mg/dl (26.5uMol) over 48 hours.
• Increase in SeCr by 1.5 times the baseline established within the past 7 days
• Urine output less than 0.5 ml/kg/h for 6 hours.

Question 2

What regions of the nephrons are most susceptible to ischemic acute tubular necrosis?

Answer 2

The areas in the Outer medulla:
The late proximal tubule and the thick ascending limb.

These areas have relatively low O2 delivery and very high demand. The inner medulla has lower oxygen delivery, but less of an O2 demand

Question 3

Types of urine sediment and what they indicate:

Dysmorphic RBCs

RBC casts

Hyaline casts

Brown casts

WBC casts

Answer 3

Dysmorphic RBCs - Glomerulonephritis

RBC casts - Glomerulonephritis

Hyaline casts - Pre-renal or hypovolemia

Brown casts - ATN

WBC casts - Interstitial nephritis, pyelonephritis

Question 4

What are the indications for Dialysis in AKI

Answer 4

Hyperkalemia not controlled by treatment: above 7mM
Acidosis, below 7.2
Severe, symptomatic fluid overload
Uremic symptoms, pericarditis, pleuritis, encephalopaity

Question 5

Dialysis indications in CKD

Answer 5

Patients with or progressing to stage 5 CKD within 1 year.

Any of the following conditions, provided they are Non-responsive to medical therapy

Serositis
Pruritis
Cognitive impairment
GI irritation, malnutrition
Inability to manage volume, pulmonary edema
Inability to control blood pressure
Acid base or electrolyte abnormalities