Approach to Oliguria and Proteinuria

Question 1

Urine output of:

Anuria

Oliguria

Polyuria

Answer 1

Anuria: <50-100 ml/day

Oliguria: <400-500 ml/day

Polyuria: >3,000 ml/day

Question 2

To be diagnosed with chronic kidney disease, the patient must have what symptoms?

Answer 2

One of the following:
Albuminuria
Urine sediment abnormalities
Electrolyte abnormalities
Histological abnormalities
Structural abnormalities
History of kidney transplant

AND a GFR <60 ml/min

Question 3

At what point does AKI become CKD?

Answer 3

If it is less than 3 mo. with GFR < 60 ml/min and/or markers of kidney damage is present, the patient has AKI.

After 3 mo., they have CKD.

Question 4

What is the GFR in CKD from stages 1 to 5?

Answer 4

Stage 1: >90
Stage 2: 60-89
Stage 3: 30-59
Stage 4: 15-29
Stage 5: <15

Question 5

Are patients with a stage 1 and stage 2 GFR always considered to have CKD?

Answer 5

No, not unless they have evidence of kidney damage.

Question 6

What are the top 3 causes of CKD?

Answer 6

1. DM
2. HTN
3. Glomerulonephritis

Question 7

Signs and symptoms of CKD include:

Answer 7

Edema
HTN
Low urine output
Foamy urine
Uremia
Pericardial friction rub
Asterixis (tremor at wrist)
Uremic frost

Question 8

What is a “poor measure of kidney function”?

Answer 8

Serum creatinine

Question 9

What are two measurements of GFR?

Answer 9

Estimated GFR (eGFR): done via formula. It is limited in use and is not helpful in settings of rapidly changing creatinine levels.

Measured GFR: most accurate, but is only done at specific institutions.

Question 10

Creatinine clearance tends to ___________ GFR.

Answer 10

Overestimate GFR

Question 11

How is proteinuria determined?

Answer 11

Urine albumin to creatinine ration or urine protein to creatinine ratio

Question 12

What are the “3 simple tests to identify most CKD patients”?

Answer 12

eGFR
Urine albumin-to-creatinine ratio or urine protein-to-creatinine ratio
Urinalysis

Question 13

What is the most common imaging of the kidney?

Answer 13

Renal ultrasound

Question 14

What are the renal ultrasound findings for CKD? (4)

Answer 14

Atrophic or small kidneys
Cortical thinning
Increased echogenicity
Elevated resistive indices

Question 15

What is doppler renal US evaluate?

Answer 15

Renal artery stenosis or renal vein thrombosis or resistant index

Question 16

What is an abdominal CT used for?

Answer 16

Detecting masses and stones

Question 17

When is an abdominal MRI used?

Answer 17

To evaluate renal artery stenosis, renal vein thrombosis or renal masses.

Question 18

What are the complications from CKD? (8)

Answer 18

Proteinuria: low salt diet, BP control.

HTN

Hyperlipidemia: statin therapy.

Anemia

Metabolic acidosis

Hyperkalemia

CKD-BMD, leading to abnormalities in Ca++, phosphorus and vitamin D abnormalities.

Volume overload

Question 19

What is renal replacement therapy (RRT) include?

Answer 19

Hemodialysis
Peritoneal dialysis
Renal transplant (living or deceased)

Question 20

What are the indications for dialysis?

Answer 20

A: severe acidosis
E: electrolyte disturbance (usually hyperkalemia)
I: ingestion
O: volume overload
U: uremia

Question 21

What are the 3 common diagnostic tests for AKI?

Answer 21

UA with microscopy**
Urine albumin-to-creatinine ratio or protein-to-creatinine ratio**
Renal US

Question 22

The following etiologies of AKI are treated with…

Prerenal patients:
Acute tubular necrosis:
GN:
Acute interstitial nephrtitis:

Answer 22

Prerenal patients: IV fluid
Acute tubular necrosis: supportive care
GN: immunosuppression or plasmaphoresis
Acute interstitial nephrtitis: D/C offending agents

Question 23

Generally, the treatment for AKI is…

Answer 23

Supportive

• avoid HTN
• D/C nephrotoxins
• renal replacement

Question 24

What is nephrotic syndrome vs. nephrotic range proteinuria?

Answer 24

Nephrotic syndrome occurs if there is low serum albumin, whereas nephrotic range proteinuria has normal serum albumin.

Question 25

What are 6 complications of nephrotic syndrome?

Answer 25

Edema
Hyperlipidemia
Infection (due to loss of IgG in urine)
Thrombosis
Vitamin D deficiency (due to loss of vit. D binding protein)
Anemia (due to urinary loss of transferrin and EPO)

Question 26

What the 2 methods of edema in nephrotic syndrome?

Answer 26

1. Low intravascular oncotic pressure (underfill theory)

2. Renal sodium retention (overfill theory) - secondary to RAAS activation

Question 27

What is on the differential for nephrotic syndrome?

Answer 27

Diabetic nephropathy
Minimal change disease
FSGS
Membranous nephropathy
Monoclonal related diseases

Question 28

The most common way to diagnose nephrotic syndrome and nephritic syndrome is..

Answer 28

Renal biopsy

Question 29

What are the goals in treating nephrotic syndrome (underlying etiology, edema, proteinuria, hyperlipidemia, thrombosis, infection)?

Answer 29

Underlying etiology: may need immunosuppression

Edema: reduce Na+ intake, diuretics

Proteinuria: lower BP

Hyperlipidemia: statins

Thrombosis: blood thinners

Infection: IVIg supplementation

Question 30

Patients with nephritic syndrome usually have…

Answer 30

Active urinary sediment (hematuria, dysmorphic RBCs, casts, WBC casts, etc.)

Question 31

Renal tubular epithelial cells, transitional epithelial cells, granular casts or waxy casts in the urine suggest…

Answer 31

Acute tubular necrosis

Question 32

WBCs, WBC casts, or urine eosinohils in urine suggest…

Answer 32

Acute interstitial nephritis or pyelonephritis

Question 33

Dysmorphic RBCs and RBC casts in urine suggests…

Answer 33

Vasculitis or GN

Question 34

Proteinuria, hematuria, dysmorphic RBCs and RBC casts in urine suggest…

Answer 34

Nephritic syndrome

Question 35

Heavy proteinuria, lipiduria, minimal hematuria suggests…

Answer 35

Nephrotic syndrome

Question 36

Hyaline casts in urine suggests…

Answer 36

Non-specific prerenal azotemia

Question 37

WBCs, RBCs and bacteria in urine suggests…

Answer 37

UTI