AKI and CKD Flashcards
Prof Dr Wong Chew Ming
Define AKI
- Abrupt decrease in kidney function
- Resulting in retention of urea and other nitrogenous waste products
- Retention in urine production and
in the dysregulation of extracellular volume and electrolytes
According to KDIGO 2012 for staging of AKI, what’s the parameter used to stage?
- Increase in SERUM CREATININE by >0.3mg/dL within 48 hours
- Urine output <0.5mL/kg/hr >6 consecutive hours
State the pre-renal cause of AKI
IMPAIRED PERFUSION
An adaptive response to severe volume depletion and hypotension, with structurally intact nephrons
- Cardiac failure
- Sepsis
- Blood loss
- Dehydration
- Vascular occlusion
State the renal cause of AKI
State the post-renal cause of AKI
Luminal
- Stones
- Clots
- Sloughed papillae
Mural
- Renal tract malignancy
- Stricture
Extrinsic compression
- Pelvic malignancy
- BPH
- Retroperitoneal fibrosis
If untreated, obstructive nephropathy leads to IRREVERSIBLE TUBULOINTERSTITIAL FIBROSIS
List some cause of high serum creatinine
- Renal dysfunction
- High muscle mass
- Medications that inhibit the kidney tubular secretion
List the cause of low serum creatinine
- Improved renal function
- Loss of muscle mass/malnutrition/amputation
- Dilutional effect/fluid overload
What are the causes of high blood urea?
- GI or mucosal bleeding
- Steroid use
- Protein loading
What’s the value of urea creatinine ratio that suggests pre-renal AKI
> 20(mg/dL)
70(mg/dL)
State the normal urine output
0.1 - 1.5 mL/kg/hr
800 - 2000 mL/day
State the amount of urine excretion for polyuria
> 3000 mL/day (diuretic phase)
State the amount of urine excretion to classify it as oliguria
<0.3 mL/kg/hr
<500 or <400 mL/day
State the amount of urine excretion for anuria
<50 or 100mL/day
If patient presented with
- Hematuria with dysmorphic red blood cells
- Red blood cell casts
- Varying degree of albuminuria
State the possible diagnosis
Proliferative glomerulonephritis
If patient presented with
- Heavy albuminuria with minimal or absent hematuria
State the probable diagnosis
Non-proliferative glomerulonephritis
If patient presented with
- Multiple granular and epithelial cell cast with free epithelial cells
State the probable diagnosis
Acute tubular necrosis in a patient with underlying acute kidney injury
If patient presented with isolated pyuria
What is the probable diagnosis?
Infection or tubulointerstitial disease
If patient presented with normal urinalysis with few cells, no casts, and no or minimal proteinuria
What is the probable diagnosis?
In presence of AKI:
- Pre-renal disease
- Urinary tract obstruction
- Hypercalcemia
- Acute phosphate nephropathy
- Myeloma cast nephropathy
In presence of CKD:
- Ischemic nephropathy
- Hypertensive nephrosclerosis
- Urinary tract obstruction
- Hepato-renal disease
- Cardio-renal disease
Interpret the following result for urea:creatinine ratio
1. 40-100:1
2. >100:1
3. <40:1
- Normal or post-renal cause of AKI
- Pre-renal cause
- Intrinsic renal damage
State the causes of increased urea:creatinine ratio
Mnemonic: Drivers Can use GPS
- Dehydration/pre-renal failure
- Corticosteroids
- GI hemorrhage
- Protein-rich diet
- Severe catabolic state
State the causes of increased urea:creatinine ratio
Mnemonic: I am a SIMPLE SR
- Severe liver dysfunction
- Intrinsic renal damage
- Malnutrition
- Pregnancy
- Low-protein diet
- SIADH
- Rhabdomyolysis
If we do MRI with gadolinium for a patient of eGFR <30mL/min, what will it lead to?
Nephrogenic systemic fibrosis
State the complications of AKI
- Fluid overload
- Hyperkalemia
- Metabolic acidosis
- Protein catabolism
- Reduced immunity
- GI bleeding
State the indication for dialysis
Mnemonic: AEIOU
- Acidosis (Severe metabolic acidosis pH<7.1)
- Excess potassium (Severe hyperkalemia >6.5 mmol/L)
- Intoxication
- Oedema (Refractory fluid overload)
- Uremia
Define chronic renal failure
GFR<60mL/min/1.73m2 for >3months with or without kidney damage
State the causes of CKD
- DM
- HTN
- Chronic glomerulonephritis
- Chronic pyelonephritis
- Renovascular disease
- Reflux nephropathy; obstructive uropathy
- Urinary stone disease; myeloma
- Analgesic nephropathy; uric acid nephropathy
What’s the key to management of CKD?
- General measures (Avoid nephrotoxic drugs and avoid dehydration)
- Slow progression
- Manage complications
State (4) common nephrotoxic drugs
- NSAIDS
- Antibiotics (GENTAMICIN)
- Contrast media (Contrast for CT scan etc)
- Traditional or herbal medications
