Nephrotic syndrome

Question 1

What is nephrotic syndrome?

Answer 1

Presence of proteinuria (>3.5g/24h)
Hypoalbuminaemia (<30g/L)
Peripheral oedema

Question 2

What other 2 features are commonly seen in nephrotic syndrome other than the diagnostic features?

Answer 2

Hyperlipidaemia

Thrombotic disease

Question 3

What is nephritic syndrome?

Answer 3

Presence of AKI
HTN
Active urinary sediment (red cells and red cell casts)

Question 4

Does the urine in nephrotic syndrome contain casts?

Answer 4

Very few.

Question 5

If a patient presents with isolated heavy proteinuria but no other features of nephrotic syndrome, what can this be called?

Answer 5

Nephrotic-range proteinuria

Question 6

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

Answer 6

Minimal change disease

Question 7

What is the most common cause of nephrotic syndrome in adult males?

Answer 7

Primary glomerular diseases

Question 8

What is the most common cause of nephrotic syndrome in adult females?

Answer 8

Secondary glomerular disease

Question 9

What is the most common cause of nephrotic syndrome in younger adults?

Answer 9

FSGS (focal segmental glomerulosclerosis)

Question 10

What is the most common cause of nephrotic syndrome in older adults?

Answer 10

Membranous nephropathy

Question 11

What is the most common cause of nephrotic syndrome in diabetics?

Answer 11

Diabetic nephropathy

Question 12

Is nephrotic or nephritic syndrome more common in pts with IgA nephropathy, membranoproliferative glomerulonephritis, and post-infectious glomerulonephritis?

Answer 12

Nephritic

but both possible

Question 13

When can minimal change disease occur in adults?

Answer 13

Idiopathic
Relation to NSAID use
Hodgkin’s lymphoma

Question 14

Why is it called minimal change disease?

Answer 14

Light microscopy finds normal glomeruli or mild mesangial proliferation

Question 15

What does electron microscopy show in minimal change disease?

Answer 15

Diffuse effacement of the epithelial cell foot processes

Question 16

What does immunofluorescence show in minimal change disease?

Answer 16

No immune complex deposition

Question 17

How is minimal change disease treated?

Answer 17

Steroids

Question 18

What does light microscopy show in FSGS?

Answer 18

Segmental areas of mesangial collapse and sclerosis affecting some but not all glomeruli

Question 19

What causes primary FSGS?

Answer 19

Idiopathic - unknown

Question 20

What can cause secondary FSGS?

Answer 20

HIV
Obesity
Reflux nephropathy

Question 21

How is primary FSGS treated?

Answer 21

Immunospression

Question 22

How is secondary FSGS treated?

Answer 22

Reducing intraglomerular pressure (renin-angiotensin blockade)

Question 23

How does FSGS commonly present?

Answer 23

Haematuria
HTN
Reduced renal function

Question 24

How is FSGS diagnosed?

Answer 24

Renal biopsy

Question 25

What does light microscopy show in membranous nephropathy?

Answer 25

basement membrane thickening without assoc. cellular proliferation or infiltration

Question 26

What does immunofluoresence show in membranous nephropathy?

Answer 26

Diffuse, granular IgG deposition throughout the capillary walls

Question 27

What does electron microscopy show in membranous nephropathy?

Answer 27

Electron-dense deposits in the subepithelial space | New basement membrane growth between subepithelial immune deposits leads to the classic 'spike and dome' appearance

Question 28

Membranous nephropathy is usually idiopathic, but what may it be due to?

Answer 28

Hep B AI disease Malignancy Adverse drug reactions

Question 29

How does diabetic nephropathy usually present?

Answer 29

Microalbuminuria | Prgrssive fall in eGFR

Question 30

How does diabetic nephropathy present in microscopy?

Answer 30

Mesangial expansion, glomerular basement membrane thickening, and glomerular sclerosis leading to the development of Kimmelstiel-Wilson nodules

Question 31

Amyloidosis is responsible for what % of nephrotic syndrome cases?

Answer 31

~10%

Question 32

How is Amyloidosis investigated?

Answer 32

Presence of a monoclonal paraprotein in urine or plasma

Question 33

What is the primary insult leading to the development of nephrotic syndrome?

Answer 33

High-grade glomerular proteinuria | - heavier protein loss the more likely the development of the full-blown syndrome

Question 34

Why do patients become hypoalbuminaemic in nephrotic syndrome?

Answer 34

Albumin is lost in urine

Question 35

What does the liver do in hypoalbuminaemia?

Answer 35

Synthesises albumin, LDL, VLDL, and lipoprotein

Question 36

How does lipiduria appear in nephrotic syndrome?

Answer 36

lipid sediment, fatty casts, oval fat bodies, or free fat droplets in teh urine

Question 37

How does hypercoagulability occur in nephrotic syndrome?

Answer 37

Loss of coagulation inhibitors in the urine | Increased synthesis of procoagulatory factors by the liver

Question 38

How does the oedema occur in nephrotic syndrome?

Answer 38

Decreased oncotic pressure from the hypoalbumiaemia as well as primary renal sodium retention in the collecting tubules

Question 39

Why are patients with nephrotic syndrome at increased risk of infection?

Answer 39

Loss of immunoglobulins and complement in the urine

Question 40

Nephrotic syndrome is 1 of the 3 causes of severe oedema (anasarca); what are the other 2?

Answer 40

CHF | Severe hepatic disease

Question 41

What are the complications of nephrotic syndrome?

Answer 41

Proteinuria and oedema, which can become generalised (anasarca) Protein malnutrition, with a negative nitrogen balance due to marked proteinuria Hypovolaemia due to over-diuresis, particularly in the presence of hypoalbuminaemia Acute kidney injury secondary to hypovolaemia, ischaemic injury, non-steroidal anti-inflammatory drugs Hyperlipidaemia and accelerated atherosclerosis Hypercoagulability causing arterial plus venous thrombosis. Immunocompromised state and infections Rapidly progressive glomerulonephritis

Question 42

What is the basis for diagnosing nephrotic syndrome?

Answer 42

``` Hx and examination Quantification of proteinuria Urinalysis for casts Serological studies Renal biopsy ```

Question 43

What features should be included in taking a history in someone with suspected nephrotic syndrome?

Answer 43

PMH Full medication history FH of causative diseases Previous know renal disease

Question 44

What features should be included in an examination of someone with suspected nephrotic syndrome?

Answer 44

``` Assessment of oedema and severity Features of hypoalbuminaemia Protein malnutrition Xanthelasmata Any additional features depending on ?cause ```

Question 45

What investigations should be done in someone with suspected nephrotic syndrome?

Answer 45

``` Proteinuria quantification Evaluation of fresh urine sampel for casts Renal function FBC Lipid profile Serum albumin TFTs HIV test Serum complement Any other tests depending on presenting features and clinical suspicians ```

Question 46

What imaging should be done in someone with suspected nephrotic syndrome?

Answer 46

Appropriate imaging of any suspected malignancies | Renal USS esp. if renal biopsy taken

Question 47

What group of patients with nephrotic syndrome do not usually need a renal biopsy?

Answer 47

Children -90% minimal change disease so nothing will be seen on biopsy that aids diagnosis Biopsy only for refractory cases

Question 48

What are the contraindications for percutaeous renal biopsy in nephrotic syndrome?

Answer 48

Bleeding diathesis resistant to correction Multiple, bilateral renal cysts Renal tumour Hydronephrosis Active renal infection Small kidneys secondary to chronic irreversible disease Severe and resistant hypertension.