Lecture 5: Nephritic and nephrotic conditions

Question 1

How can glomerular disease be classified?

Answer 1

• hereditary
• primary (most common): disease originates from glomerulus
• secondary to systemic diseases e.g. lupus, diabetes mellitus, bacterial endocarditis

Question 2

What is glomerulonephritis?

Answer 2

Inflammation of the glomerulus

many of these can go on to form chronic kidney disease

Question 3

What structures in the glomerulus are prone to damage?

Answer 3

• capillary endothelial cell lining
• glomerular basement membrane
• mesangium supporting the capillaries
• podocytes

Question 4

What is nephrotic syndrome characterised by?

Answer 4

Proteinuria (>3g per day) because there is an increased permeability to albumin as a result of the glomerular basement membrane damage and increase in pore size

• causes hypoalbuminaemia, causing oedema
• because the body is losing lots of protein, the body stimulates lipid production= hyperlipidaemia

Question 5

How do we manage nephrotic syndrome?

Answer 5

• blood pressure control
• ACE inhibitors (reduce BP in glomerulus)
• control hyperlipidaemia
• anticoagulation drugs (risk of thrombosis increases as albumin decreases)
• treatment of underlying cause when possible

Question 6

What are some key nephrotic conditions? (lead to nephrotic syndrome)

Answer 6

Diabetic nephropathy

• excess glucose in blood binds to proteins, especially at efferent arteriole, obstructing flow (hyaline atherosclerosis), causing an increase in GFR
• over time mesangial cells secrete more structural membrane, thickening the basement membrane
• so over time we see a reduction in GFR

Minimal change disease
-no significant changes under light microscope

Membranous glomerulonephritis

• subepithelial deposition of immune complexes, causing thickening of basement membrane
• this causes it to become leaky as the pores get bigger

Focal segmental glomerulosclerosis (FSGS)

• only affects some of the glomeruli, and of them, only some of the glomerulus is affected
• podocytes damaged causing proteins to build up in glomerulus: hyalinosis: sclerosis

Question 7

What is the leading cause of end stage renal disease?

Answer 7

Diabetic nephropathy

Question 8

How do we treat diabetic nephropathy?

Answer 8

• keep watch on diabetic patient and their GFR
• treat hypertension
• have good glycemic control
• take ACE inhibitors
• take angiotensin receptor blockers

Question 9

What is the most common cause of nephrotic syndrome in children under 6?

Answer 9

Minimal change disease

Question 10

What are the causes of membranous glomerulonephritis?

Answer 10

85% idiopathic

Can be secondary to infections (syphilis/malaria/hep B), tumours, drugs (heroin/mercury), systemic illnesses (lupus)

Question 11

How do you treat membranous glomerulonephritis?

Answer 11

Immunosuppressants

Treat underlying cause

Question 12

What are the causes of FSGS?

Answer 12

• idiopathic

- secondary to sickle cell, HIV, heroin abuse, kidney hyperfusion

Question 13

How do you treat FSGS?

Answer 13

Steroids

inconsistent results

Question 14

What are some symptoms and signs of acute nephritic syndrome?

Answer 14

-oliguria/anuria (low or no urine output)
-hypertension
-hematuria
(sometimes proteinuria, uraemia (raised blood urea), fluid retention)
-loin pain, headaches, general malaise

Question 15

How do you treat acute nephritic syndrome?

Answer 15

Steroids

Question 16

What are some key nephritic conditions?

Answer 16

IgA Nephropathy (Berger's disease)
-hypertension and high IgA levels: deposited in mesangium: sclerosis

Rapidly progressive glomerulonephritis

• severe glomerular injury cuasing leakage of fibrin, macrophages and epithelial cells to proliferate
• cresent shape mass forms reducing glomerular blood supply
• loss of renal function within days-weeks

Post-streptococcal glomerulonephritis
-1-3 weeks following group A beta-hemolytic streptococcal infection of tonsils/pharynx/skin

Goodpasture’s syndrome

• antibodies to type 4 collagen (strand of collagen that makes up the glomerular basement membrane) causing inflammation
• results in rapidly progressive glomerulonephritis, acute renal failure and lung haemorrhage

Question 17

What is the most common primary glomerular disease worldwide?

Answer 17

IgA Nephropathy (Berger's disease)
-causing recurrent hematuria

Question 18

How do you treat IgA Nephropathy (Berger’s disease)?

Answer 18

-control BP
-antihypertensives
-steroids
(20% will develop CKD)

Question 19

How do you treat rapidly progressive glomerulonephritis?

Answer 19

• high dose steroids
• immunosuppressants
• plasma exchange

Question 20

How do you treat post-streptococcal glomerulonephritis?

Answer 20

Antibiotics to treat remaining infection

• good prognosis in children
• 60% recovery rate in adults, rest will develop hypertension/renal impairment

Question 21

Why do you get lung haemorrhage in Goodpasture’s syndrome?

Answer 21

Similar type of collagen is found in the lungs

Question 22

How do you treat Goodpasture’s syndrome?

Answer 22

Plasma exchange (to remove antibodies)
Corticosteroids (remove inflammation)

Question 23

What is loin pain?

Answer 23

Pain in area above belly button to the sides of the body, not usually at front of body