2: Acute Renal Failure Flashcards
Uremia
There is a sx of high nitrogen in blood
Azotemia
Dx by the amount of nitrogenous waste
Significant serum Creatinine increase
0.5mg/dL increase over 24hrs
Exotoxin causing Acute tubular necrosis
Cisplatin Ethylene glycole Cyclosporine Aminoglycoside (7-10 days)** Radiocontrast dye (24-48hrs)**
Endotoxin causing Acute tubular necrosis
Calcium Light chains of MS Myoglobin Hemoglobin Uric acid
Damage to Interstitium
Drug/Allergy (penicillin)
Infection (Legionnaire disease, Hantavirus)
Infiltration (Sarcoidosis, Lymphoma/Leukemia)
Autoimmune (SLE)
Prerenal Azotemia- cause
Hypovolumia
Cause of Acute renal failure-post renal to accumulate crystals (ATM)
Acyclovir
Methotrexate
Triemetrine
Granular cast- “Muddy brown”
ATN
Hyaline cast
Benign. Could be by anything
RBC cast
Glomerulonephritis
WBC cast
Pyelonephritis
Acute infective interstitial nephritis
Eosinophilic cast
Acute allergic interstitial nephritis
Prerenal ARF
Retain sodium and water
BUN is reabsorbed more than creatinine-> BUN/Creatinine ratio is high >20
FeNa:500
Renal ARF
BUN/Creatinine ratio is low
FeNa: >2%
Osm <20
Complications
Metabolic acidosis Hyperkalemia Hyponatremia Hypervolumia Hyperphosphatemia Hypocalcemia
Management
Stop the insult Correct volume Hydration (watch out for over hydration) Correct electrolytes Some drug (Furosemide, Dobutamine, Ca channel blocker)
Hypovolumia- causes
- Hemorrhage
- Dehydration
- Burns
- GI loss: vomiting, diarrhea
- Replaced in other space: ascites, peritonitis
Acute glomerulonephritis or vasculitis- cause
RPGN
Acute Tubular Necrosis- causes
Ischemia
Toxins
Clinical course in ATN
Initial phase: Oliguria (400mL/day)
Postrenal ARF
MC: Obstruction bladder neck
*Above the bladder to cause ARF, it must be BILATERAL**
