Hydronephrosis, ARF, CKD, ESRD Flashcards
US is usually first choice when imaging kidneys, when should you use CT?
when looking for masses or stones
also higher sensitivity for PKD
avoid IV contrast- nephrotoxic
What kind of imaging study is preferred in children?
radionuclide studies
In moderate to advanced KD, gadolinium can lead….
severe syndrome of nephrogenic systemic fibrosis
What is the gold standard for RVT?
MRI
Why isn’t renal arteriography and venography really used?
more invasive than CT/MMRI
can see arterial and venous occlusions
What is IVP used for?
High sensitivity and specify for stones
but not really used
Indications for renal biopsy?
Nephrotic syndrome: SLE
Acute nephritic syndrome
Unexplained ARF
When is renal biopsy NOT indicated?
In patient with: Isolated glomerular hematuria,
Low grade proteinuria
What is a page kidney?
bleeding under the capsule of the kidney after biopsy , causing compression of the collecting system leading to damage to the kidney, requires removal of the capsule
What is hydronephrosis?
Unilateral or bilateral edema of the collecting system
-usually asxs
-poss. pain if obstructive involved
+/- change in UOP
What are some obstructive etiologies for hydronephrosis?
Bladder outlet obstruction consider GI and GYN masses, stones, BPH
Imaging for hydronephrosis?
US
What are some non-obstructive etiologies for hydronephrosis?
Large diuresis can distend intrarenal collecting system (ie. Diabetes insipidus).
CT if US not indicative
Tx for hydronephrosis?
stenting
What is AKI (ARF)?
Abrupt (within 48hrs) decline in renal filtration function
Usually reversible
Labs consistent with ARF?
decreased in GFR and UOP (UOP less than 0.5ml for >6hrs)
increased Urea
Increased Creatinine (Azotemia)
What is considered pre-renal?
Anything that happens above the kidney. Ex. Renal Hypoperfusion, hypovolvemia, poor fluid intake
What is considered intrinsic AKI?
Damage within the kidneys themselves, ex. Damage to glomeruli, tubular or interstitium
What is considered post-renal AKI?
Damage after the kidney. Urology problem. Ex. Obstructive nephropathy, prostatic hyperplasia, bladder tumors, etc.
Most AKI are due to?
Pre-renal causes. Hypoperfusion leading to decrease in renal perfusion
In AKI due to pre-renal causes will show…on labs
Increased BUN/Cr ratio
Tx for pre-renal AKI?
Maintain euvolemia, give fluids. Avoid nephrotoxic drugs
64 y/o M with chronic systolic HF. BUN 41mg/dL. Cr 1.4 mg/dL. What is likely cause of elevated BUN/Cr ratio?
- Acute tubular necrosis
- Bilateral ureteral obstruction
- Renal hypoperfusion
- Fe deficiency anemia
Renal Hypoperfusion
What would the BUN/Cr ratio be in ATN?
normal
Bilateral ureteral obstruction is a….
Post renal problem
Rhambdomylysis is a…process
ATN
myoglobin clogs up the tubule
What are some causes of AKI due to intrinsic causes?
ATN, Intersisital. Glomerular, vascular
causes for post renal AKI?
Obstructive:
BPH, urolithiasis, bladder dysfunction (anticholinergic drugs), bladder CA
Sxs of post renal AKI? Dx?
lower abd pain
bladder US
labs: elevated BUN: Cr ration
Tx for postrenal AKI?
catheter, stent, surg depending on etiology
remove what ever is causing the back up
How do you correct prerenal AKI?
intrarenal?
Postrenal?
IVF- normal hemodynamics
Avoid nephrotoxic agents
removal of obstruction
for all: consider short term dialysis
What will you see on UA in ATN?
Muddy brown casts. ATN makes up 85% of intrinsic AKI
Is AKI reversible?
YES
can do dialysis
HD can be done via
fistula > graft (due to risk of infx)
tunneled line
When should you dialyze?
Weight
Physical exam/fluid overload
electrolytes imbalance?
UOP/uremic complications
Unresponsive acidosis
pH<7.1
What is ATN?
Tubular damage due to ischemia or nephrotoxins
What are some nephrotoxins?
Aminoglycosides, Amp B, Vanco, contrast, CNI
Tx for ATN?
o Avoid volume overload, avoid hyperK, protein restrict, +/- diuretics
What can you use to renally protect from IV contrast?
Give N-acetylcystine/IVF with bicarb
What is AIN?
Inflammatory response leading to edema and possible tubular cell damage. Usually caused by nephrotoxic drugs but can also be infectious or autoimmune
What will you see on UA in AIN?
Eosinophiluria
Tx for AIN?
Steroids +/- dialysis
What causes intrinsic GN?
IgA nephropathy, post infectious strep GN, MPGN, Goodpastures
What will you see on UA in intrinsic GN?
RBC casts
Tx for intrinsic GN?
steroids and plasma exchange
Renal function in ESRD?
<15 or dialysis
What is GFR?
Glomerular filtration rate:
- Degree of impairment
- Varies by age, gender, and body size
- Measurement via MDRD
What is creatinine?
Waste product of creatinine phosphate from muscle which passes in the blood and through kidneys
Dependent on muscle mass
What is Azotemia?
Nitrogen in the blood
Occurs when renal function can no longer efficiently clear metabolites
Results from renal parenchymal damage
How do you determine Azotemia?
by measures of BUN and Cr
leads to uremia
How do you monitor for uremia?
with blood urea nitrogen (BUN), urea produced by liver, excreted by urine
At what stages of CKD will you see uremia?
3-5
Sxs of uremia?
Malaise, N/V, dyspnea, impaired mentation, RLS, pruritus, weakness, insomnia, muscle cramping. Can lead to spontaneous bleeding, cardiac arrest, coma, seizure
weight loss/muscle wasting, HTN, ecchymosis, asterixis, kussmaul respirations
Work up for CKD?
GFR*
Labs: BUN and Cr elevated, proteinuria present, +/-microalbuminuria
Abn H &H, lytes, UA
consider bx
Tx for CKD?
ACE/ARBs- slows progression
Tx underlying condition: Epo, Fe, antiplatelets
low protein diet, fluid restriction
Ca/ Vit D supplements
consider dialysis/transplant
What causes hypervolemia?
Hyponatremia with hypervolemia usually CHF, nephrotic syndrome, ESRD or ESLD
Labs in CKD during hypervolemia?
Hgb and Hct decreased
Tx for hypervolemia?
Fluid restrict
+/- diuretics
+/- dialysis
What causes hypovolemia?
lost from EC compartment, GI tract, kidneys, “third spacing” skin/injured tissues
Labs for CKD pt with hypovolemia?
H&H increased
urine Na decreased
Urea increase
Tx for hypovolemia?
give isotonic IVFs
What are some causes of ESRD/CKD?
PKD,DM, glomerulonephritis. HTN, SLE, nephrolithiasis
Describe PKD
multiple bi cysts
reduction of renal mass reduces kidney func.
mostly genetic (75%) Autosomal Dominant
Sxs of PKD?
hematuria, infx, pain from rupture, nephrolithiasis, nocturia
also assoc. with hepatic and pancreatic cysts
How do we eval for PKD?
US
Tx for PKD?
pain management
ACE/ARB
aggressive abx is sxs
Transplantation
Half of ESRD causes are due to…
DM
these patient also have increased risk of CV and stroke due to large vessel atherosclerosis
When should Metformin should be avoided?
in pts with Cr greater than 1.4 in women and 1.5 in men who need CT imaging
should hold Metformin day of scan and 2 days after
this is to avoid lactic acidosis
95% of renal artery stenosis is due to..
atherosclerosis
How do we dx renal artery stenosis?
Gold standard: renal angiogram
Start with: Dopple US
Tx of renal artery stenosis?
angioplasty
+/- stenting
Epidemiology of SLE?
9x more in females
African americans > caucasians
nephritis with proteinuria
What is the most common type of renal stone? What does it look like on imaging?
calcium (75-85%)
radiopaque
Major causes of death for dialysis pts?
CV disease, infx, withdrawal from dialysis
What is KDRI?
kidney donor risk index, summarizes risk of graft failure
high percentage = higher chance of graft failure
What makes someone more likely to have a rxn to transplant?
previous transplant
pregnancy
blood transfusions
possible post transplant s/s?
Hyper/hypoglycemia HTN/hypotension N/V/D Wound complications Anemia Watch for hyper/hypovolemia
new meds and drug-drug interaction
