Acute kidney injury

Question 1

Acute kidney injury is the abrupt decline in ____manifested by an acute rise in __________

Answer 1

Acute kidney injury is the abrupt decline in GFR manifested by an acute rise in serum creatinine

Question 2

true or false: high mortality rate in AKI

Answer 2

true: 21%

Question 3

mesurement of GFR

Answer 3

1. inulin is the gold standard since it is freely filtered and not secreted or reabsorbed but…
2. creatinine is more convenient but while it is freely filtered and not reabsorbed it is s secreted and thus overestimates GFR

Question 4

low mol weight protein released by all nucleated cells at constant rate

Answer 4

cystatin C

Question 5

Cystatin C is affected by

Answer 5

thyroid dz

Question 6

oliguric AKI

Answer 6

low urine output portend worse prognosis

Question 7

non-oliguric AKI

Answer 7

nml urine output despite inadequate clearance– may have severely reduced GFR with well-maintained urine output

Question 8

Pre-renal AKI

Answer 8

perfusion related

Question 9

intra-renal AKI

Answer 9

intrinsic

Question 10

post-renal

Answer 10

obstructive AKI

Question 11

risk factors for AKI

Answer 11

1. advanced age
2. preexisting chronic kidney disease
3. DM
4. underlying heart or liver disease

Question 12

in perfuison related AKI we see a decline in kidney perfusion due to a __________

Answer 12

true intravascular volume depletion

Question 13

decreased kidney perfusion can be caused by

Answer 13

1. decreased effective plasma volume such as in hepatic failure, sepsis
2. renal artery stenosis
3. hypovolemia such by diuretics, trauma, diarrhea or vomiting
4. decreased cardiac output like CHF or massive PE
5. interference with autoregulation

Question 14

what exacerbates reduced kidney perfusion in patients with volume depletion

Answer 14

NSAIDs or ACE inhibitors

Question 15

As kidney perfusion decreases, GFR is maintained via autoregulation involving _______ (potent efferent ________) and __________(__________the afferent arteriole and ameliorate the effect of AII)

Answer 15

As kidney perfusion decreases, GFR is maintained via autoregulation involving angiotensin II (potent efferent vasoconstrictor) and prostaglandins (vasodilate the afferent arteriole and ameliorate the effect of AII)

Question 16

is a high or low FeNa (<1%) consistent with perfusion-related AKI

Answer 16

low

Question 17

obstructive causes of AKI

Answer 17

1. obstruction of bladder outlet
2. nephrolithiasis
3. retroperitoneal fibrosis
4. intratubular obstruction

Question 18

obstruction AKI can lead to

Answer 18

hydronephrosis

Question 19

intrinsic AKI

Answer 19

1. acute tubular necrosis
2. interstitial nephritis
3. Glomerular disease
4. Small vessel disease

Question 20

acute tubular necrosis is caused by

Answer 20

prolonged ischemia or toxin exposure

Question 21

what do we see in the pathology of acute tubular necrosis

Answer 21

denuding of tubular epithelial cells that most prominently in the PCT and loop of Henle

Question 22

what is the most common cause of AKI in hospital patients

Answer 22

ischemic ATN

Question 23

pathophysiology of ischemic ATN:

1. intratubular obstruction causes a
2. _________across injured tubular cells allows filtered toxins to return to blood
3. there is a reduction in kidney ______ due to either increased _____ or reduction in _______

Answer 23

1. intratubular obstruction causes a rise in tubular pressure
2. Backleak of glomerular filtrate across injured tubular cells allows filtered toxins to return to blood
3. there is a reduction in kidney blood flow due to either increased vasoconstrictors or reduction in vasodilators

Question 24

toxic ATN (4)

Answer 24

1. radiocontrast dye
2. aminogluycoside antibiotics
3. amphotericin
4. Myoglobin (rhabdomyolysis)

Question 25

intersitial nephritis causes

Answer 25

1. drugs such an antibiotics (70%) 2. infections 3. autoimmune

Question 26

clinical findings of AIN

Answer 26

1. fever 2. rash 3. eosinophilia 4. UA- WBCs, WBC casts

Question 27

hallmark of glomerulonephritis

Answer 27

proteinuria

Question 28

what do we see in the urine in glomerulonephritis

Answer 28

RBCs and RBCs casts

Question 29

thrombotic microangipathy is caused by damage to the

Answer 29

endothelial cells

Question 30

in thrombotic microangiopathy, _____ constituents enter wall of renal arterioles and results in narrow lumens and ________in small vessels and _____ AKI. It is often accompanied by __________

Answer 30

in thrombotic microangiopathy, plasma constituents enter wall of renal arterioles and results in narrow lumens and thrombi in small vessels and ischemic AKI. It is often accompanied by microagiopathic hemolytic anemia

Question 31

causes of thrombotic microangiopathy

Answer 31

1. autoimmune disease 2. malignant HTN 3. drugs 4. infection 5. idiopathic

Question 32

urinalysis of thrombotic microangiopathy

Answer 32

1. bland | 2. maybe some RBCs or granular casts

Question 33

urinary findings in ATN

Answer 33

muddy brown casts

Question 34

urinalysis findings in interstitial nephritis

Answer 34

1. WBC | 2. WBCs casts

Question 35

urinalysis findings in glomerulonephritis

Answer 35

1. proteinuria 2. dysmorphic RBCs 3. RBC casts

Question 36

why would you do an ultrasound?

Answer 36

1. rule out obstruction | 2. evaluate kidney size

Question 37

radionucleotide is done to determine if it wither

Answer 37

ATN or Renal infarct

Question 38

management of patients with AKI

Answer 38

1. treat underlying cause 2. discontinue all non-essential nephrotoxins 3. modify drug dosages

Question 39

metabolic complications of AKI

Answer 39

1. hyperkalemia 2. metabolic acidosis 3. hypocalcemia 4. avoid hypermagnesemia

Question 40

true or false: volume expansion frequent in patient with oliguric AKI

Answer 40

yep

Question 41

diuretic management in AKI

Answer 41

important but pt. may be unresponsive even to large doses diuretics

Question 42

uremic complications

Answer 42

1. platelet dysfunction 2. pericarditis 3. uremia is catabolic state 4. CNS complications 5. Anemia

Question 43

newer/experimental therapies for AKI

Answer 43

1. natriuretic peptides 2. designer Ab 3. vasodilators