Approach To Oliguria and/or Proteinuria ~Selby Flashcards
What is the definition of anuria?
Anuria UOP < 50-100 ml/day
What is the definition of oliguria?
Oliguria UOP < 400-500 ml/day
What is the definition of polyuria?
Polyuria UOP > 3,000 ml/day
What is the definition of azotemia?
Azotemia Elevated blood urea nitrogen (BUN) without symptoms
What is the definition of uremia?
Uremia Elevated BUN with symptoms (N/V, confusion, pruritus, metallic taste in mouth, fatigue, anorexia, etc…) Note: symptoms of uremia are non-specific with multiple etiologies causing them
What are the diagnostic parameters of CKD?
-If it is < 3 months with GFR < 60 ml/min and/or markers of kidney damage present, then the patient has acute kidney injury (AKI) -After 3 months, then patient can be labeled with CKD
Describe what this means:
In absence of evidence of kidney damage, neither GFR category Stage 1 or Stage 2 fulfill the criteria for CKD
In absence of evidence of kidney damage, neither GFR category Stage 1 or Stage 2 fulfill the criteria for CKD
Stage 1 GFR: greater than or equal to 90 ml/min
Stage 2 GFR: 60 to 89 ml/min
What is the main cause of CKD?
Vast majority caused by Diabetes or HTN (64%)
What is the clinical presentation of CKD?
- Clinical presentation of CKD is quite variable depending on severity of CKD
- Many patients are asymptomatic and only find out they have CKD from routine
laboratory testing
•Signs and symptoms of CKD include:
–Edema
–Hypertension
–Decreased urine output (UOP)
–Foamy urine (proteinuria)
–Uremia (Nausea/vomiting, confusion, pruritus, metallic taste in mouth,
fatigue, anorexia, etc…)
–Pericardial friction rub
•Pericarditis and pericardial effusion
–Asterixis
–Uremic frost
What are the 3 simple tests to identify most CKD patients?
3 simple tests to identify most CKD patients:
- eGFR
- urine albumin-to-creatinine ratio or urine protein-to-creatinine ratio
- urinalysis
What are the renal U/S findings for CKD?
Renal U/S findings for CKD:
- Atrophic or small kidneys
- Cortical thinning
- Increased echogenicity
- Elevated resistive indices
•Renal Ultrasound
–Most commonly used imaging of kidney
–Can evaluate the size of kidneys, cortical thickness, echogenicity (increased echogenicity also seen in AKI), presence of hydronephrosis, renal mass, cysts, etc…
What is a major complication of CKD that can result in bone thinning?
CKD-BMD (previously renal osteodystrophy)
Secondary hyperparathyroidism
What are the indications for dialysis?
Indications for dialysis:
A: Severe Acidosis
E: Electrolyte disturbance (usually hyperkalemia)
I: Ingestion (ex: ethylene glycols, methanol, etc…)
O: Volume overload
U: Uremia
what are the parameters of acute kidney injury?
what are the major causes of prerenal azotemia?
what are the major causes of postrenal azotemia?
What is the clinical presentation of AKI?
- Clinical presentation of AKI is quite variable depending on severity of AKI
- Many patients have no symptoms with mild AKI
- Signs and symptoms of AKI include:
–Edema
–Hypertension
–Decreased urine output
- Anuria
- Oliguria
- Non-oliguria
–Foamy urine (proteinuria)
–Hematuria
–Shortness of breath
•if pulmonary edema present
–Uremia (Nausea/vomiting, confusion, pruritus, metallic taste in mouth,
fatigue, anorexia, etc…)
–Pericardial friction rub
•Pericarditis and pericardial effusion
–Asterixis
–Uremic frost
What are the common diagnostic tests for AKI?
Common Diagnostic test:
- UA with microscopy
- Urine albumin/crratio or protein/crratio
- Renal U/S
What are the complications of AKI?
•Hypervolemia
–Pulmonary edema
–Heart failure
•Electrolyte abnormalities
–Hyperkalemia
–Hyperphosphatemia
–Hypocalcemia
–Hypermagnesemia
- Hyperuricemia
- Uremia
- Pericarditis
- Metabolic acidosis
- Bleeding
–Platelet dysfunction, BUN > 100 mg/dL
•Need for dialysis
What is the treatment of AKI?
•Depends on etiology
–Prerenal patients need IV fluid
–Acute tubular necrosis (ATN) patients need supportive care
–Glomerulonephritis could need immunosuppression or plasmapheresis
–Acute interstitial nephritis (AIN) needs discontinuation of offending agent and/or steroids (controversial)
- Correct underlying disease if possible
- Mostly supportive
–Avoid Hypotension
–DiscontinueNephrotoxins(Antibiotics, NSAIDs, ACEi/ARBs, PPI, IV Contrast, etc…)
–Renal replacement if needed
- Usually hemodialysis
- Timeis nephrons!
What are the parameters of nephrotic syndrome?
•Nephrotic syndrome
–Proteinuria
•> 3-3.5 grams/day
–Hypoalbuminemia
–Peripheral edema
–Hyperlipidemia
–Lipiduria
–If serum albumin is normal in setting of nephrotic range proteinuria, then the patient…
•Key Point:
–If serum albumin is normal in setting of nephrotic range proteinuria, then patient does not have true nephrotic syndrome but instead has nephrotic range proteinuria
–Helps with differential (i.e. possible Secondary FSGS)
What are the complications of nephrotic syndrome?
•Edema
–Low serum albumin but more likely increased urinary sodium retention
–Increased TBW and Na+
•Hyperlipidemia
–Etiology not well understood
–Low oncotic pressure stimulates hepatic lipoprotein synthesis resulting in hypercholesterolemia
•Infection
–Urinary loss of IgG
–Occasionally have to supplement with IVIG
•Thrombosis
–Etiology not well understood
•Venous or arterial thrombosis
–Higher risk when Albumin < 2.0 or 2.5 g/dL
–Urinary loss antithrombotic factors
•Antithrombin III, plasminogen, protein S, etc…
–Increased levels of procoagulant factors
•↑ Fibrinogen, Coagulation Factors (II, V, VII, VIII, X, XIII), etc…
What are the two theories that state why people with nephrotic syndrome have edema?
- Low intravascular oncotic pressure (Underfilltheory)
- Renal sodium retention (Overfill theory)
–Secondary to low renal perfusion from low effective circulating volume (RAAS activation)
–Primary sodium retention by the kidneys
