Nephrology/Urology Flashcards
What does RIFLE help diagnose
Acute Renal Failure ARF and Acute kidney injury
R of RIFLE
Risk of renal dysfunction:
GFR decreased more than 25% or sCR 1.5 fold increase
and UO is less than .5ml/kg/hr for 6 hours
I of RIFLE
Injury to the kidney:
GFR decrease 50% or more, or sCR 2 fold increase
AND UO less than .5 ml/kg/hr for 12 hours
F of RIFLE
Failure of kidney function:
GFR 75% or more decrease or sCR is 3x higher, or more than 4mg/dl in setting of acute increase of at least .5mg/dL
UO criteria: less than .3 ml/kg/hr for 24 hrs (oligouria) or anuria for 12 hrs
L of RIFLE
loss of kidney function: persistant ARF - loss of function for more than 4 wks
E of RIFLE
End stage kidney disease ESKD or ESRD: complete loss kidney function more than 3 mo
What 2 disease cause most of the ARF cases?
reduced renal perfusion (lack blood flow to kidneys), and acute tubular necrosis
3 categories of ARF causes
prerenal, intrinsic renal, and postrenal
5 prerenal causes ARF
hypovolemia, hypotension, poor circulation volume (CHF, cirrhosis, early sepsis, nephrotic syndrome), aortic aneurysm, renal artery stenosis or embolic dz
what category of ARF causes are most common?
prerenal
5 intrinsic renal causes of ARF
acute tubular necrosis, nephrotoxins (NSAIDs, aminoglycosides, contrast), interstitial disease, glomerulonephritis, vascular disease (ie vasculitis, polyarteritis nodosa)
Post renal causes
tubular obstructions, obstructive uropathy (urolithiasis, BPH, bladder outlet obstruction)
What disease sx are.. N/V/D, pruritus, drowsiness, dizzy, hiccups, SOB, anorexia, hematochezia
ARF
what sx indicate prerenal cause of ARF
tachycardia and hypotension
signs of postrenal arf
distended bladder, CVA tenderness, enlarged prostate
what do I order if suspect arf?
GFR, sCR, BUN, serum cystatin, urine biomarker options (IL 8, KIM1)
what does a kidney less than 10 cm on ultrasound suggest?
chronic kidney problem
when should dialysis be started for pts with ARF?
when sCR is above 5-10 mg/dL and/or if there is unresponsibe acidosis, electrolyte disorders, fluid overload, uremic complications
CKD definition
GFR less than 60ml/min/1.73 m2 or presence of kidney damage from more than 3 mo
CKD stage 1
kidney damage but normal GFR over 90 and persistent albuminuria
CKD stage 2
damage plus mild GFR drop to 60-89
CKD stage 3
GFR 30-59
CKD stage 4
GFR 15-29
CKD stage 5
kidney failure with GFR under 15
how will stage 1 or 2 CKD pt present?
asymptomatic no BUN or sCR increase
what will increase by stage 3 of CKD?
sCR and BUN, also other hormones will be weird (PTH, EPO, calcitriol)
other signs of stage 4 CKD
anemia, acidosis, high K+, low Ca++, hyperphosphatemia
4 most common cause of CKD
DM, HTN, glomerulonephritis, and polycysitic kidney dz
what is gold standard of CKD diagnostics
GFR (MDRD equation is most accurate) for kids use a peds GFR calculator
what will be elevated in CKD?
BUN and sCR, serum cystatin C may be elevated as well if below 88GFR
CKD treatment
- ACE or ARB to slow renal damage
- Manage comorbid conditions
- EPO, iron supplement, antiplatelet therapy considered to keep Hgb 11-12
- Restrict PRO, Na, K, and phosphorus in diet
- get pneumococcal vaccination and flu!!
- hemodialysis, transplant etc.
GN def
damage of renal glomeruli by deposition of inflammatory PRO in the glomerular membranes from an immunologic response
focal GN
less than half of the GN affected
diffuse GN
most glomeruli are affected
common sx of glomerularnephritis
hematuria (tea or coke colored), edema of face in morning, edema feet or ankles evening, HTN common
Diagnostics for GN
if recent streptococcal infection do a antistreptolysin 0 titer. UA finds hematuria, serum complement C3 will be low, renal biopsy helps with diagnosis/severity
treatment GN
- steroids immunosuppress
- diet: restrict salt and fluids
- dialysis if azotemia (high Cr and/or urea) with sx present
- ACE and other comorbid meds
Nephrotic syndrome
excretion of more than 3.5g of protein per 1.73m squared of body surface in 24 hours
Nephrotic syndrome can lead to ____ due to loss of ____
thrombosis due to loss of Protein S, C and antithrombin III
Sx of nephrotic syndrome
scrotal swelling, facial edema, oligouria, SOB, weight gain, abdominal distension, anorexia, ascites, HTN, retinal sheen, skin striae
Oval fat body is what key finding
for nephrotic syndrome in the UA: a renal tubular cell that reabsorbed some excess lipids in the urine
