Oliguria and/or Proteinuria DSA and CIS Flashcards
What defines anuria, oliguria, and polyuria?
anuria: < 50-100 ml/day
oliguria: < 400-500 ml/day
polyuria: > 3000 ml/day
What is significant about the sx of uremia?
(must have elevated BUN)
sx are often non-specific w/ multiple etiologies causing them
What common drugs are nephrotoxic?
What do you always ask about them?
NSAIDs
antibiotics
proton pump inhibitors
always ask which ones, how many at a time, and for how long
What type of contrast dye can be nephrotoxic?
IV iodine contrast
(not the oral kind)
What defines acute kidney injury vs CKD?
< 3 mos w/ GFR < 60 ml/min and/or markers of kidney damage present = AKI
after 3 mos, pt can be labeled w/ CKD
What are the clinical markers of kidney damage?
How many are required to dx AKI or CKD
one or more required:
albuminuria
urine sediment abnormalities
electrolyte and other issuew due to tubular damage
histology or structural abnormalities
Hx of kidney transplant
What are the stages of CKD?
GFR greater than or equal to 90 is CKD stage ___
stage 1 = normal or high GFR
GFR btw 60-89 is CKD stage ___
2 = mild decrease
GFR btw 45-59 is CKD stage ___
btw 30-44 is stage ___
3a = mild to moderate decr
3b = moderate to severe decrease
GFR btw 15-29 is CKD stage ___
4 = severe decrease
GFR < 15 is CKD stage ___
5 = kidney failure/ESRD
Neither GFR category stage 1 or 2 apply (with the associated decreased GFR) if what?
if no sx
What are the top two causes of CKD?
diabetes = 38%
HTN = 26%
(total cause 64%)
What is asterixis?
type of negative monoclonus where body parts can just flop around according to google
(he has a picture of a flopping hand)
Sx of CKD and AKi
What is uremic frost?
deposition of urea crystals on skin
seen in CKD and AKI
What is the formula for estimating creatinine clearance?
the cockroft-gault formula
How can creatinine clearance skew estimated GFR?
tends to overestimate GFR because creatinine is freely filtered at glomerulus but is also secreted by tubules making urine creatinine concentration higher than expected
(use cockcroft-gault equation instead)
What tests can you do measure proteinuria?
urine albumin to creatinine ratio or urine protein to creatinine ration = random, spot urine
24 hr urine total protein collection = annoying, usually not done unless completely necessary
When is is eGFR not accurate?
What is the most accurate way to measure GFR?
in settings of rapidly changing creatinine (AKI)
measured GFR most accurate but only performed in limited institutions
How is serum creatinine used in diagnosis of CKD?
not often = poor marker of kidney function
What are the renal U/S findings for CKD?
atrophic or small kidneys
cortical thinning
increased echogenicity
elevated resistive indices
What is a doppler renal US used for?
to look for renal A stenosis or renal vein thrombosis or resistive index
high resistive indices (>0.7-0.8) indicate resistance to arterial flow w/in kidney
What is an abdominal CT scan better for evaluating in kidney dz?
better at detecting masses and kidney stones
can evaluate for same things as renal US
What is the most commonly used imaging of kidney?
renal US
What are the indications for dialysis?
AEIOU
A: severe acidosis
E: electrolyte disturbance (usually hyperkalemia)
I: Ingestion of toxins
O: volume overload
U: uremia
What are the 3 types of renal replacement therapy?
hemodialysis
peritoneal dialysis
renal transplant
What are BP goals in CKD?
no proteinuria: < 140/90
proteinuria: < 130/80
Tx for proteinuria
low salt diet
BP control
ACEi, ARB, aldosterone antagonist, renin inh, non-D CCB
Tx for anemia in CKD?
oral or IV iron
EPO stimulating agents
Tx for metabolic acidosis in CKD?
bicarbonate supplementation if HCO3 <22
Tx for hyperkalemia in CKD?
renal failure diet = low salt, potassium, and phosphorus
diuretics
sodium plystyrene sulfonate or patiromer
What is CKD-BMD and how do you tx?
secondary hyperparathyroidism to CKD (previously renal osteodystrophy)
tx w/ renal failure diet
posphorus binder
Vit D supplementation
calcimimetics to lower PTH
dialysis
AKI definitions and stages
What category of AKI do renal pelvis issues fall under (papillary necrosis, stones)?
postrenal AKI
What are the 3 intrinsic causes of AKI?
tubular necrosis (ischemia = 50%, toxins = 35%)
interstitial nephritis = 10%
glomerulonephritis = 5%
What sx is seen in AKI but not often in CKD?
shortness of breath
if pulmonary edema is present
What labs do you obtain on all pts w/ AKI?
What imaging is commonly run?
urinalysis w/ urine microscopy
urine albumin/Cr ration or urine protien/Cr ratio
renal US
Equation for fraction excreted Na
What is the general tx of AKI?
mostly supportive
avoid hypotension
discontinue nephrotoxins
renal replacement if needed - usually hemodialysis
What is the association w/ serum albumin and nephrotic syndrome?
if serum albumin is normal w/ nephrotic range proteinuria, then the pt DOES NOT have true nephrotic syn but instead nephrotic range proteinuria
Why can thrombosis occur in nephrotic syndrome?
not well understood - can be venous or arterial
higher risk w/ albumin < 2.0 or 2.5 g/dL
urinary loss of antithrombotic factors (antithrombin III, plasminogen, protein S, etc)
increased levels of procoagulant factors
Who is at high risk for thrombo-embolism in nephrotic pts?
serum albumin < 20 g/L
climical hypovolemia
bed rest/intercurrent illness
membranous nephropathy
What are the two theories of pathogenesis of edema in nephrotic syn?
low intravascular oncotic pressure bc low albumin = underfill theory
renal sodium retention secondary to low renal perfusion from low RAAS or primary sodium retention by kidneys = overfill theory
What is the classic presentation of nephrotic syndrome?
new onset hypertension
new onset edema
proteinuria
lipiduria
hyperlipidemia
minimal hematuria
What are the monoclonal disease related etiologies of nephrotic syndrome?
multiple myeloma
amyloidosis
monoclonal Ig deposition disease (MIDD) = light chain, heavy chain, or both
What are the 5 main etiologies of nephrotic syndrome to know?
diabetic nephropathy
minimal change dz
FSGS
membranous nephropathy
monoclonal disease related
How do you tx thrombosis in nephrotic syn?
heparin or warfarin
consider prophylactic anticoagulation for serum albumin < 2.5 g/dL
How to do tx predisposition to infection seen in nephrotic syndrome?
give IV Ig
In what kidney dz do you usually have active urinary sediment?
nephritic syndrome
(nephrotic syn usually has “bland” urinary sediment)
What kidney dz is due to thrombotic microangiopathy?
nephritic syndrome
What heart dz can cause nephritic syndrome?
endocarditis
When are complement levels helpful in kidney dz dx?
low complement levels are very helpful in ddx of nephrITIC syndrome
low C4 and C3 –> classical pathway
low C3 onl –> alternative pathway activated
What do you see in urine in acute tubular necrosis?
renal tubular epithelial cells
transitional epithelial cells
granular casts
waxy casts
What do you see in urine in acute interstitial nephritis or pyelonephritis?
WBC
WBC casts
urine eosinophils
What do you see in urine in vasculitis or glomerulonephritis?
dysmorphic RBCs
RBC casts
What do you see in urine in nephritic syndrome?
proteinuria < 3.5 g/day
hematuria
dysmorphic RBC and RBC casts
What do you see in urine in non-specific, prerenal azotemia?
hyaline casts
What do you see in urine in UTI?
WBCs
RBCs
bacteria
How does hyperkalemia affect resting membrane potential?
makes membrane potential less negative –> easier to depolarize
D-dimer and BNP lab findings should be interpreted with caution in what setting?
renal failure
What does a CXR look like in pulmonary edema?
diffuse alveolar consolidation
What is the initial management and tx of hyperkalemia?
calcium gluconate to antagonize cardiac AP
To lower potassium levels:
insulin and dextrose
furosemide (will also help w/ pulm edema and anasarca)
albuterol nebulizer
could give sodium polystyrene sulfonate
What glomerular disorders have subEPIthelial deposits?
post-strep glomerulonephritis
membranous glomerulonephritis
What glomerular dzs have subENDOthelial deposits?
MPGN type I
SLE (diffuse proliferative GN)
(probably more but these are the main ones I memorized for the last test)
What is the general management for most cases of AKI?
avoid nephrotoxins (NSAIDs, IV contrast, etc)
renal dose all medications (discontinue metformin)
avoid hypotension
avoid dehydration
What is meloxicam?
prescription NSAID
(consider nephrotoxicity)
What is normal capillary refill time?
<2-3 seconds
anything greater –> sign of dehydration or anemia
What are signs of hypovolemia or prerenal azotemia?
hemoconcentration
hypovolemic hyponatremia
contraction metabolic alkalosis
BUN/Cr ration > 20:1
hyaline casts in urine
What are signs of acute tubular necrosis seen in urinalysis?
proteinuria
renal tubular epi cells
transitional epi cells
granular casts
FENA > 2%
How are prerenal azotemia and acute tubular necrosis connected?
if prerenal azotemia is present long enough, the pt will start to develop ATN
What is the prognosis of AKI?
once kidney fxn declines regardless of etiology, there is no guarantee that fxn will recover or improve
if it improves, still no guarantee it will go back to baseline
can take up to 3 mos for recovery –> after 3 mos, if not to baseline = CKD
