Renal disease: acute kidney disease Flashcards
Definition of Acute kidney injury.
Clinical syndrome characterized by rapid decline in GFR and renal function of varying severity, initiated by a multitude of causes.
Phases of Acute kidney injury. (4)
- Induction
- Extension
- Maintenance
- Recovery
Grades of AKI.
I-V
Acute kidney injury Categorization. (3)
Prerenal (hemodynamic): renal hypoperfusion.
Intrinsic renal: ischemia/nephrotoxin damages the renal parenchyma.
Postrenal (obstructive): acute obstruction of the urinary tract.
Prerenal kidney injury due to
hemodynamic: renal hypoperfusion → decreased GFR, normal renal parenchyma
● Rapid correction of GFR following restoration of renal perfusion.
Intrinsic renal injury due to
ischemia/nephrotoxin damages the renal parenchyma.
Postrenal kidney injury due to
acute obstruction of the urinary tract.
Uroabdomen
● Trauma
● Bladder may be palpable
● May not be grossly hematuric
Ureteral/urethral obstruction
● Uroliths/debris
● Urethral/bilateral ureteral obstruction
● Unilateral ureteral - no biochemical abnormalities if the other kidney is normal
● Unilateral ureteral with CKD - acute on chronic
● Renal pelvis dilation, blunting of diverticuli, proximal ureteral dilation
Difference between AKI and acute kidney disease.
AKI ≤7 days
AKD >7 days
CKD ≥3 months
Acute kidney disease is a Post-AKI state/early CKD.
How should acute kidney disease be treated?
Graded?
Monitored?
Monitor and treat Acute kidney disease like AKI.
● Grades (I-V) based on creatinine.
● Recovery monitored with GFR biomarkers (creatinine, SDMA, BUN).
Unit conversion for creatinine: mg/dL to mcmol/L
multiply mg/dL by 88 to mcmol/L
e.g. creatinine 5 mg/dL = creatinine 440 mcmol/L
AKD grade I is further categorized:
AKD grade I subtypes:
IC
IB
IA
Drugs/conditions contributing to AKI (7)
● NSAIDs, ACEIs,
diuretics, cyclosporine,
radiocontrast agents,
hypercalcemia,
bacterial endotoxins.
Intrinsic renal etiology for AKI? (4)
Diseases of large renal vessels
● Renal artery thrombosis, vasculitis, renal vein compression
Diseases of the renal microvasculature and glomeruli
● Glomerulonephritis, vasculitis, hypertension…
Ischemic/nephrotoxic acute tubular necrosis
● Renal hypoperfusion, endogenous/exogenous toxins
Other processes involving the tubulointerstitium
● Neoplastic infiltration, oxidative injury, infectious disease
Intrinsic systemic disease with potential to cause prerenal AKI? (6)
● Infectious diseases: leptospirosis, babesiosis, parvovirosis
● Sepsis and MODS
● Hypo-and hyperadrenocorticism
● Pancreatitis
● Heatstroke
● Cutaneous and renal glomerular vasculopathy
Describe Nephrotoxins and kidney injury.
● Endogenous (e.g. myoglobin) or exogenous
● Different mechanisms of injury
● Intrarenal vasoconstriction, tubular cell toxic injury, intratubular obstruction.
Name some exogenous nephrotoxins.
● Contrast agents
● Drugs: aminoglycosides, amphotericin B, cyclosporine, tacrolimus, albumin…
● Grape, raisin, currant (dogs)
● Lily (cats)
● Ethylene glycol
● Melamine
● Cholecalciferol (vitamin D) - rodenticide