Nephrotic Syndrome - MD

Question 1

What happens when albumin leaks into urine?

Answer 1

Blood loses its ability to absorb extra fluid → EDEMA

Question 2

What is the reference range for normal urinary protein excretion?

Answer 2

< 150 mg/d

Question 3

What is the difference between transient and persistent proteinuria?

Answer 3

Transient → proteinuria on a single test (may be due to fever, exercise, UTI, etc..)
Persistent → proteinuria present on 2 or more occasions (needs evaluation)

Question 4

What are the collection of symptoms that indicate kidney damage?

Answer 4

1) Proteinuria (>3.5 g/d)
2) Hyperlipidemia
3) Edema of legs, feet, ankles
4) Hypoalbuminemia

Question 5

What are the most common etiologies of proteinuria?

Answer 5

1) Glomerular
- ↑ filtration of macromolecules → leaks across glomerular capillary wall
2) Overflow
- filtered load is increased to a level that exceeds the normal proximal re-absorptive capacity

Question 6

What is the difference between primary and secondary nephrotic syndrome?

Answer 6

Primary → absence of identifiable systemic disease

Secondary → presence of identifiable systemic disease

Question 7

What type of histopathology is the most common cause of nephrotic syndrome in children?

Answer 7

Minimal Change Disease (80%)

Question 8

What is the cause of Minimal Change Disease, what are the S/S, and what is the Tx?

Answer 8

• No cause is found in most patients (immunologically mediated → abnormal T-cell function)
• Severe edema, ascites, pleural effusion, NSAIDs may cause
• Tx: Corticosteroid therapy

Question 9

What are the causes of Focal Segmental Glomerulosclerosis?

Answer 9

• Idiopathic
• Secondary: reflux nephropathy, HIV, or heroin-associated nephropathy, sickle cell disease, obesity, late-stage focal glomerulonephritis
• Familial Inherited form of FSGS: African-american patients, Alport syndrome, nail-patella syndrome

Question 10

What is the most common systemic disease causing nephrotic syndrome?

Answer 10

Diabetic glomerulosclerosis due to either DM Type I or Type II

Question 11

What type of glomerulonephritis usually presents with mixed nephrotic and nephritic syndrome?

Answer 11

Membranoproliferative glomerulonephritis

-Presents with hematuria, RBC casts, lipiduria, (oval fat bodies), & nephrotic-range proteinuria

Question 12

What are the clinical manifestations of Nephrotic Syndrome?

Answer 12

• Edema
• Proteinuria (>3.5 g/day)
• Hypoalbuminemia (<3.0 mg/dL)
• Associated hypertriglyceridemia/hypercholesterolemia
• All results in: edema, hypercoagulability, hypothyroidism, & anemia

Question 13

What proteins are lost during Nephrotic Syndrome and what processes do their loss cause?

Answer 13

• Immunoglobulin → immunocompromised state
• Antithrombin III/Protein C&S → hypercoagulability
• EPO & transferrin → anemia
• Thyroxine-binding globulin → hypothyroid
• Cholecalciferol binding globulin → ↓ Vit D, ↓ Ca++, ↑ PTH

Question 14

Why is there an increase in lipids in patients with Nephrotic Syndrome?

Answer 14

↓ oncotic pressure & hypoalbuminemia → ↑ hepatic synthesis of proteins and lipids with concurrent decreased peripheral metabolism

Question 15

What is the significance of oval fat bodies?

Answer 15

oval fat bodies are markers for nephrotic range proteinuria

Question 16

Will Nephrotic syndrome lead to metabolic alkalosis or metabolic acidosis?

Answer 16

Severe hypoproteinemia may lead to a persistent metabolic alkalosis.
(steady-state plasma [HCO3-] rises as plasma albumin drops)

Question 17

What are the physical exam findings associated with Nephrotic syndrome?

Answer 17

• Swelling of the face (children)
• Periorbital edema followed by swelling of the entire face
• Dependent edema + weight gain
• Frothy urine
• Skin Striae
• HTN + orthostatic HTN
• oliguria