CIS Flashcards
acute kidney injury
absolute increase in serum creatinine of .3 mg/dL or
50% increase in serum creatinine or
Reduction in urine output consisting of oliguria of less than .5 mL/kg/hr for longer than 6 hours
Note– BUN is not used in the diagnosis of renal failure
Acute vs. Chronic renal failure
Compare with Creatinine from before Size of kidneys on US Sediment on u/a Stigmata of Chronic Renal Failure: - Anemia - Hyperparathyroidism (osteodystrophy) - A/V fistula - Hyperphosphatemia
differential for renal acute kidney injury toxins
Exogenous: direct and vasoconstriction
Endogenous: myoglobin, hemoglobin, light chAINS, uric acid, calcium
Work-up for AKI. Urinalysis.
Prerenal
- Normal or hyaline casts
Intrarenal
- Tubular cell injury: Muddy-brown, granular, epithelial casts
- Interstitial nephritis : Pyuria, hematuria, mild proteinuria, granular and epithelial casts, eosinophils
- Glomerulonephritis: Hematuria, marked proteinuria, red blood cell casts, granular casts
- Vascular disorders: Normal or hematuria, mild proteinuria
Postrenal
Normal or hematuria, granular casts, pyuria
FeNA, Urine Na and Bun/ Creat Ratio in pre-renal
less than 1% FeNa
less than 10 Urine Na
greater than 20:1 BUN Creat Ratio
FeNA, Urine Na and Bun/ Creat Ratio in ATN or toxic injury or early vascular disorders
FeNA > 1% , Urine Na > 20, BUN/ Creat Ratio less than 20:1
FeNA, Urine Na and Bun/ Creat Ratio in glomerulonephritis
FeNa less than 1%, Urine Na less than 10, BUN/ Creat Ratio less than 20:1
“g-low-merulonephritis,” everything is “low”
Renal Ultrasound
Signs of hydronephrosis Kidneys size PCKD Stones Tumors
Acute injury, what do you do first before even thinking?
give them fluids
If the fluids improve the BUN/ Creatinine ratio, then you know that it was pre-renal (diagnosis by treatment)
What are possible causes of pre-renal azothemia
Intravascular volume depletion and or hypotension: Hemorrhage, GI loss: vomiting/diarrhea, Renal loss: diuretics, diabetes (mellitus and incipidus), Dermal losses (sweating)
Decreased effective intravascular volume: Congestive heart failure, Cirrhosis, Hepatorenal syndrome, Peritonitis
Systemic vasodilation/renal vasoconstriction: Sepsis, Hepatorenal syndrome
Large-vessel renal vascular disease: Renal artery thrombosis or embolism, Renal artery stenosis, Cholesterol emboli
What medications make prerenal azothemia worse, and may even push patient into acute tubular necrosis with the same degree of dehydration?
Cyclosporine Tacrolimus ACEIs, ARBs, NSAIDs Radiocontrast agents
Why does infection lower albumen?
it is an acute phase reaction
Another cause of increased BUN
upper GI bleeding– reabsorption of BUN
hyaline casts mean?
pre-renal
granular casts mean?
ATN
RBC casts mean?
glomerulonephrotic
what will we see on ultrasound of acute ATN?
normal kidneys
difference in recovery period between pre-renal and ATN?
pre-renal gets better with fluids
ATN will take a week or so to get better because of the necrosis
what medications may cause acute renal failure?
Aminoglycosides Radiocontrast agents Acyclovir Cisplatin Sulfonamides Methotrexate Cyclosporine Tacrolimus Amphotericin B Foscarnet Pentamidine Ethylene glycol Toluene Cocaine HMG-CoA reductase inhibitors
What is the significance of the negative finding for eosinophills. What condition it rules out?
acute interstitial nephritis
Interstitial Nephritis– meds that make you suspect
β-LACTAM ANTIBIOTICS Penicillin Cephalosporins Ampicillin Methicillin Nafcillin
DIURETICS Furosemide Hydrochlorothiazide Triamterene
OTHER ANTIBIOTICS Sulfonamides Vancomycin Rifampin Acyclovir Indinavir
NSAIDS Ibuprofen Naproxen Indomethacin
most common side effect of statin?
rhabdomyalysis
what screams rhabdomyalysis?
very positive for blood but very few RBC
besides renal failure, 2 other complications of rhabdomyalysis?
compartment syndrome (from swelling) disseminated intravascular coagulation
