Acute Kidney Injury

Question 1

Sudden impairment of kidney function –> retention of nitrogenous and other waste products normally cleared by the kidneys

Answer 1

Acute Kidney Injury

Question 2

Common Diagnostic Features of AKI

Answer 2

↑ in BUN concentration
↑ in plasma or serum creatinine concentration
↓ in urine volume

Question 3

KDIGO 2012 Definition of AKI

Answer 3

↑ in SCr by >0.3 mg/dL (>26.5 mmol/L) w/n 48 hrs
↑ in SCr to >1.5 x the baseline - occured w/n the prior 7 days
urine volume <0.5 mL for 6 hrs

Question 4

MC form of AKI

Answer 4

prerenal azotemia

Question 5

Due to inadequate renal plasma flow and intraglomerular hydrostatic pressure to support normal glomerular filtration

Answer 5

prerenal azotemia

-NO parenchymal damage

Question 6

MC causes of intrinsic AKI

Answer 6

sepsis
ischemia
nephrotoxins (endogenous and exogenous)

Question 7

Very important cause of AKI in the developing world

Answer 7

sepsis

Question 8

The site of one of the most hypoxic regions in the body

Answer 8

renal medulla

Question 9

Intrinsic AKI

Answer 9

tubular damage
glomerular damage
interstitial damage
vascular damage

Question 10

Small Vessels Damage (Intrinsic AKI)

Answer 10

Glomerulonephritis
Vasculitis
TTP/HUS
DIC
Atheroemboli
Malignant HTN
Calcineurin inhibitors
Sepsis

Question 11

Tubules (Intrinsic AKI)

Answer 11

Toxic ATN
 Endogenous (rhabdomyolysis,hemolysis)
 Exogenous (contrast,  cisplatin, gentamicin)
Ischemic ATN
Sepsis

Question 12

Intratubular (Intrinsic AKI)

Answer 12

Endogenous
 • Myeloma proteins
 • Uric acid (tumor
 lysis syndrome)
 • Cellular debris

Exogenous
• Acyclovir, methotrexate

Question 13

MC clinical conditions associated with prerenal azotemia

Answer 13

hypovolemia
↓ cardiac output
medications that interfere with renal autoregulatory responses (NSAID and inhibitors of Angiotensin II)

Question 14

Risk factors for nephrotoxicity

Answer 14

age
CKD
prerenal azotemia

Question 15

Clinical course of contrast AKI

Answer 15

↑ in SCr beginning 24–48 h following exposure
peaking within 3–5 days
resolving within 1 week

Question 16

Common findings in contrast AKI

Answer 16

low fractional excretion of sodium (FeNa) < 1

benign urinary sediment without features of tubular necrosis

Question 17

MC protein in urine and produced in the THICK ascending limb of the loop of Henle

Answer 17

uromodulin

Question 18

Occurs when the normally unidirectional flow of urine is acutely blocked either partially or totally

Answer 18

Postrenal Acute Kidney Injury

Question 19

Complete anuria early in the course of AKI is uncommon EXCEPT in the following situations:

Answer 19

complete urinary tract obstruction
renal artery occlusion
overwhelming septic shock
severe ischemia (often with cortical necrosis)
severe proliferative glomerulonephritis or vasculitis

Question 20

AKI leads to

Answer 20

hyperkalemia
hyperphosphatemia

hypocalcemia

Question 21

The fraction of the filtered sodium load that is reabsorbed by the tubules measure of both the kidney’s ability to reabsorb sodium as well as endogenously and exogenously administered factors that affect tubular reabsorption

Answer 21

fractional excretion of sodium (FeNa)

Question 22

Type 1 transmembrane protein that is abundantly expressed in proximal tubular cells injured by ischemia or nephrotoxins such as cisplatin

Answer 22

Kidney Injury Molecule-1 (KIM-1)

Question 23

Highly upregulated after inflammation and kidney injury and can be detected in the plasma and urine within 2 h of cardiopulmonary bypass–associated AKI

Answer 23

Neutrophil gelatinase associated lipocalin (NGAL aka lipocalin-2 or siderocalin)

Question 24

Hallmark of AKI

Answer 24

elevated BUN concentration

Question 25

Major complication of oliguric and anuric AKI due to impaired salt and water excretion

Answer 25

expansion of extracellular fluid volume

Question 26

An important complication of AKI particularly common in rhabdomyolysis, hemolysis, and tumor lysis syndrome due to release of intracellular potassium from damaged cells

Answer 26

Hyperkalemia

Question 27

Major cardiac complications of AKI

Answer 27

arrhythmias
pericarditis
pericardial effusion