Nephrology Flashcards
What are the MC ways to get imaging on kidneys?
US and CT
What is the benefit of US?
what is is not good at identifying?
- safe/easy to use
- initial test MCly used
- choice for obstructive dz
less sensitive to renal masses
US with doppler is used for what?
assess vascular flow
MR/CT more sensitive
What are benefits of CT?
Gold standard for renal stones
- locate ureteral obstruction
- higher sensitivity for PKD
- Evaluate tumor
- dx RVT
Who can you not give gadolinium to? why
in moderate to advanced kidney disease (GFR < 30)
leads to nephrogenic systemic fibrosis
What are ateriorgraphy and venography used for?
arterial and venous occlusions
What is intravenous pyelogram (IVP)?
used for caliceal anatomy, size of kidney, shape of kidney
high sensitivity and specificity for stones
Indications for renal biopsy?
Not indicated?
Indicated:
Nephrotic syndrom
acute nephrotic syndrome
unexplained ARF
NOT:
Isolated glomerular hematuria
low grade proteinuria
What is hydronephrosis?
how does it present?
Unilateral or bilateral edema of the collecting system
almost always asymptomatic
possible pain or change in UOP
What are causes of obstructive hydrogenphrosis? What do you do for dx?
Tx?
-bladder outlet obstruction consider GI and GYN masses, stones, BPH
US
stent
What are causes of non obstructive hydrogenphrosis? What do you do for dx?
Tx?
Large diuresis can distend intrarental collecting system (EX. Diabetes insipidus)
-CT if US is not indicative
stent
What is AKI? Is it reversible/not?
abrupt (w/in 48 hrs) decline in renal filtration function
usually reversible
What are lab values for acute renal failure?
- decrease in GFR
- UOP less than 0.5 ml/kg/hr for > 6 hrs
- increase in Urea and creatinine (azotemia)
- serum creatinine increases abruptly by more than 50% of baseline
What are the levels of kidney failure? (RIFLE)
R- risk of renal dysfunction
GFR decrease more than 25% and UOP less than .5 mL x6 hrs
I- injury to kidney
GFR decrease more than 50% and UOP less than .5 x 12 hrs
F-failure of kidney function
GFR decrease more than 75% and UOP less than .5 x24 hrs
L- loss of kidney function
for more than 4 weeks
E- end stage Renal dz
more than 3 months
Examples of pre-renal AKI?
Anything before the kidneys
renal hypo perfusion, hypovolemia, shock, GI fluid loss, poor fluid intake
Examples of intrinsic AKI?
damage to the glomeruli, tubular or interstitial, glomerularnephritis, acute tubular necrosis
Examples of post-renal AKI?
Obstruction nephrology: prostatic hyperplasia, neoplasia, nephrolithiasis, tumors
MC type of AKI?
Prerenal
Causes of Prerenal AKI
hypo perfusion leading to decrease in renal perfusion:
- decrease in intravascular volume (hemorrhage, gI losses, burns, dehydration)
- change in vascular resistance (cirrhosis, sepsis, anaphylaxis)
- low CO (CHF, PE, tamponade)
What will the BUN/Cr ratio be in prerenal AKI?
upper limit of nl 20:1
increase ratio in prerenal dz
Tx for prerenal AKI? Avoid?
Tx: maintain envolemia
Avoid: nephrotoxic drugs (NSAIDS, ACEI, Digoxin)
Intrinsic causes of AKI? (types)
- acute tubular necrosis (ATN)
- interstitial (AIN)
- glomerular (GN)
- vascular
Acute tubular necrosis is causes by?
characteristic KEY WORDS?
muddy brown casts;
ischemia, nephrotoxin, sepsis
- tubular damage due to ischemia or nephrotoxins (ahminoglycosides, vancomycin, contrast)
- prolonged hypotension/hypoxemia
Tx of Acute tubular necrosis?
Avoid?
avoid volume overload
avoid hyperK
protein restrict
+/- diuretics
-Give N-acetylcystine/IVF w/ bicarb to renal protect from radiographic contrast
What is AIN? causes of AIN?
Inflammatory response leading to edema and possible tubular cell damage
70% caused by nephrotoxic drugs
(others= strep infections)
What will UA show in AIN? how do you treat?
Eosinophiluria
steroids +/- dialysis
What is GN caused by?
Immune complex deposition/etiology:
- IgA nephropathy (Berger dz)
- postinfectious strep GN
- MPGN, Goodpastures, Wegeners
What does UA in GN show? Tx?
UA: RBC casts (bleeding from kidneys)
Tx: steroids, plasma exchange
What type of Intrinsic AKI is MC?
ATN- 85%
What are causes of post renal AKI?
Obstruction:
BPH, urolithiasis, bladder dysfunction, bladder CA
What is a common sx of pt w/ postrenal AKI?
DX? Tx?
Lower abd pain
Dx: bladder US, elevated BUN/Cr ration
Tx: catheter, stent, surgery depending on etiology
(key point= fix whatever is causing obstruction)
Again, What is tx: Prerenal intrarenal Postrenal
Tx for all?
prerenal: IVF w/ goal to nl hemodynamics
intrarenal: avoid nephrotoxic agents
Postrenal: removal of obstruction
For all: consider short-term dialysis
What should be considered when debating to dialyze or not? (Who should have dialysis)
- weight
- Physical exam/ fluid overload
- UOP/uremic complications
- unresponsive acidosis pH < 7.1
What are the stages of Chronic Kidney Disease?
1-5
1, 2, 3a, 3b, 4, 5
5= ESRD
What does GFR tell you?
Degree of impairment
varies by age, gender, body size
What is creatinine?
What is it dependent on?
Waste product of creatinine phosphate from muscle which passes in the blood through kidneys
*Dependent on muscle mass
What is Azotemia? What is it measured by?
Nitrogen in the blood
Measured by BUN and Cr (markers of nitrogen accumulation)
Why does Azotemia occur? What does it lead to?
Occurs when renal fxn can no longer efficiently clear metabolites
results from renal parenchymal damage
Leads to uremia
Uremia is monitored by what? What stages is it in?
Monitored w/ blood urea nitrogen (BUN), urea produced by liver excreted by urine
stages 3-5
Sx of Uremia
lotssssss some are:
malaise N/V insomnia cardiac arrest weight loss HTN ecchymosis Kussmaul respirations
Dx studies for CKD?
GFR= gold standard!
BUN and Cr elevated, proteinuria, microalbuminuria may be present in early stages, Abnormal hgb, hct, lytes, UA
Tx for CKD?
- slows progression: ACE/ARB
- Epo, Fe, antiplatelet therapy (goal hgb 11-12)
- low protein diet, fluid restriction, Ca/VitD supplementation
- dialysis/transplant
Hypervolemia causes what and is seen in what?
Causes hyponatremia w/ hypervolemia
seen in CHF, nephrotic syndrome, ESRD
In Hypervolemia, what happens to HgB and Hct?
Tx?
Decreased
fluid restrict
consider diuretic therapy or dialysis
Hypovolemia is caused by?
what happens to HgB and Hct?
lost from extracellular compartment > intake
-usually GI tract, kidneys
Hgb and Hct increase, urine Na down, Urea increases
Tx of hypovolemia
Give isotonic IVFs
rapid correction can lead to central pontine myelinoysis
What is polycystic kidney disease? Signs/sx?
multiple b/l cysts, (autosomal dominant MC 75%)
hematuria, infection, pain from rupture, nephrolithiasis, nocturia
weight loss, early satiety, N/V
Dx tool for Polycystic kidney dz? Tx
US is choice method
Tx: pain management, ACE/ARB, aggressive abx if symptomatic, transplantation
Diabetes Mellitus causes…
1/2 of ESRD cases!
What should be avoided in pts w/ Cr greater than 1.4 in women and 1.5 in men?
how many days after scan do you hold it?
Metformin
2 days
MC cause of renal artery stenosis?
atherosclerosis
Dx and tx of renal artery stenosis
Dx: renal angiogram is gold standard
however, Doppler US is good start
Tx: angioplasty, +/- stenting
DX and Tx of renal htn?
Dx: 2 episodes of SBP > 140 or DBP > 90
Lifestyle modifications then medications
-thiazide diuretic, ACE/ARB, Ca chan blockers
MC sx of HTN?
Trick-
usually asymptomatic
SLE is MC in? What does it cause
young female 9x more likely than males
Nephritis w/ proteinuria
Types of stones in Nephrolithiasis?
are they radiopaque or radiolucent
- Calcium 75-85%- - radiopaque
- Uric acid- radiolucent
- Cystine- radiolucent
- Stuvite- radiopaque. Pts w/ UTIs and recurrent caths
Most of Glomerulonephropathies are seen in?
kids ages 2-12 60%
Signs of Nephritic syndrome?
Tx?
hematuria, RBC casts, mild proteinuria, hTN
RBC casts present!
Tx: diuretics, salt/water restrict, dialysis
Sx of nephrotic syndrome?
Hypoalbumunemia
heavy proteinuria
hyperlipidemia
edema
Major causes of death for dialysis pts?
CV disease, infection, withdrawal from dialysis
What is KDRI? Explain
Kidney Donor risk Index summarizes risk of graft failure
KDPI 80% has higher expected risk of graft failure t
Antibodies in recipient blood can cause reaction resulting in a positive crossmatch
previous tip
pregnancy
blood transfusions
What do you need to watch for post transplant?
- new meds and drug-drug interactions
- hyper/hypoglycemia
- HTN/hypotension
- N/V/D
- wound complications
- anemia
- watch for hyper/hypovolemia
Hyperkalemia:
sign on ekg
tx
Sx: peaked T waves
hemodialysis, sodium bicarbonate, D50 + insulin, Kayexalate
Hypercalcemia:
sx
sx: bones, stones, and groans
common in hyperparathyroid and malignancies
Hypocalcemia:
sx
Trousseau sign (carpal tunnel spasm)
Chevostek sign (spasm of facial muscles)
hyperphosphatemia cause?
hypophosphatemia?
Hyper: MC 2/2 CKD
hypo: EtOH
Hypomagnesemia sign on EKG?
widening of QRS
HbA1C is ___ or great to dx DM?
6.5%
Type 1 DM characteristics, sx
autoimmune, early onset, risk of DKA
sx: polydipsia, polyuria, nocturia, gastroparesis
Type 2 DM characteristics
later onset, +FH, obesity, hyperinsulinemia
What dz is a risk factor in pts who have kidney/pancreas tx?
Gastroparesis
tx: metoclopramide, domperidone, erythromycin
What is key in preventing rejection after transplant?
Always steroids
What is Cytomegalovirus?
sx?
tx?
CMV MC viral infection found in immunocompromised pts
most prominent 1st 3 months
fevers, malaise, arthralgias, lymphocytes, thrombocytopenia
gastroenteritis, myocarditis, pneumonitis, fatality
tx= antivirals
EBV and BK virus causes what?
mononucleosis
45-50% reactivation after kidney transplant
What is the 2nd leading cause of death in liver transplant recipients?
Malignancy
