Intro To Renal Pathology

Question 1

Define GFR

Answer 1

Volume of fluid filtered from the kidney into the Bowman’s space per unit time (ml/min)
Gives an estimate of the number of working nephrons

Question 2

Formula for creatinine clearance:

Answer 2

Urine Creatine / plasma creatine x (vol/time)

Question 3

What are pre renal causes of renal failure

Answer 3

• inadequate blood supply: HF so ↓ renal perfusion, volume depletion, sepsis, severe bleeding

Question 4

What are examples of kidney diseases with a systemic etiology

Answer 4

• SLE, DM, amyloid, PAN, Wegeners (ANCA), HS purpura

Question 5

What are some features of glomerular disorders?

Answer 5

• heavy proteinuria
• RBC casts
• oval fat bodies

Question 6

Features of tubulointerstitial disorders:

Answer 6

• mild proteinuria
• functional tubular defects
• WBC

Question 7

Features for neophrotic glomerular diseases

Answer 7

• heavy proteinuria
• oval fat bodies
• free fat droplets
• few cellular elements
• fatty casts

Question 8

Features of nephritic glomerular disease

Answer 8

• red cells
• red cell casts/ granular casts
• variable proteinuria
• WBC

Question 9

What are the antibody mediated mechanisms of renal disease

Answer 9

• in situ immune complex: fixated antigens that are intrinsic to the GBM or antigens planted there (exogenous or endogenous)
• circulating immune complexes: endogenous antigens like DNA or exogenous antigens
• cytotoxic antibodies: direct cell injury or can happen WITHOUT immune complex deposits

Question 10

What are the factors that determine where the immune complexes are deposited in the kidneys

Answer 10

• charge
• location
• size

Question 11

Another mechanism of kidney diseases is the activation of the ________ complement pathway in which involves the activation of ________

Answer 11

Alternative;
C3;

Seen in dense deposit disease (type II MPGN)

Question 12

In what conditions can you expect patients to have ↓ renal mass?

Answer 12

Hypertension because it destroys some of the functional glomeruli

Question 13

What are reasons for using electron microscopy in diagnosing renal diseases?

Answer 13

• irregularities in GBM
• expansion of mesangium
• ## mainly for: looking at the deposits and their location and see the pattern of deposits

Question 14

What disease would you see “subepithelial humps”

Answer 14

Post infectious glomerulonephritis (PSGN)

Question 15

A young child has renal issues and the EM shows dense deposits in the capillary basement membrane, what is the most likely diagnosis?

Answer 15

Dense deposit disease

Question 16

EM shows splitting of the basement membrane, what is the disease and the type?

Answer 16

Alport’s; it is a hereditary cause of kidney disease

Question 17

Where do you see granular deposits in the kidneys?

Answer 17

Outer aspect of the basement membrane such as the subepithelium or mesangium