Renal Diseases

Question 1

What parts of the kidney do cystic diseases affect?

Answer 1

The cilia

Cilia are structures on tubular cells which control flow into the kidneys (get cysts from too much flow)

Question 2

Who does Autosomal Dominant Polycystic Kidney Disease affect?

Answer 2

Adults

Remember by Dominant = Adult

Question 3

What gene defects are involved in autosomal dominant polycystic kidney disease?

Answer 3

Defects in polycystic kidney disease (PKD) genes

PKD-1: 85% of cases

PKD-2: 15% of cases

Question 4

Describe the morphology of autosomal dominant polycystic kidney disease. Also, are other organs affected?

Answer 4

Remember adults have four decades to develop cysts so there are a ton

Gross: irregular surface

So many cysts that normal intervening parenchyma are squashed and are subjected to ischemic atrophy

Again, so many cysts that 1/3 of patients have asymptomatic cysts in liver

Question 5

Autosomal Dominant polycystic kidney disease

Clinical stuff

Answer 5

Remember, tons of cysts!

Symptom: flank pain (tons of cysts enlarge the kidney causing this)

Disease is typically asymptomatic until fourth decade, then renal failure

Question 6

Autosomal Recessive Polycystic Kidney Disease

Who does it affect?

Answer 6

Kids

Think recessive = less than dominant so affects kids

Question 7

autosomal recessive polycystic kidney disease

gene/gene products

Answer 7

PKHD-1 (looks like PKID) which codes for fibrocystin.

Gene defective so expect fibrosis to be a problem in this disease

Question 8

autosomal recessive polycystic kidney disease

morphology

Answer 8

gross: smooth surface*
cut: many small cysts in cortex/medulla

other organs: liver is affected by congenital hepatic fibrosis (cirrhosis)

*smooth surface cuz cysts develop in the cortex/medulla

Question 9

autosomal recessive polycystic kidney disease

clinical:

Answer 9

serious from birth, many die in infancy

if survive infancy develop cirrhosis (congenital hepatic fibrosis)

Question 10

What is Glomerularnephritis

Answer 10

Inflammation of the glomeruli (kidney filtering unit) due to deposition of immune complexes or Ab attack

Symptoms make sense given that the glomeruli are the kidney filter unit

ie patients will have nephritic syndrome (blood and protein in urine and also edema and hypertension)

Question 11

Acute poststreptococcal Glomerularnephritis

causes

Answer 11

post-infection with the sore throat type of strep (9-14 day latency)

Then caused by deposition immune complexes

Question 12

acute poststreptococcal glomerularnephritis

morphology

Answer 12

Think about complexes being deposited or “buried”

• deposits are mainly C3 (early may see IgG)
• complexes deposited as isolated humps in subepithelial space between outer GBM and Podocytes (humps like the humps of dirt created when dogs dig a hole)
• appearance is granular (like a backyard that a dog has been digging all over)

Question 13

acute poststreptococcal glomerularnephritis

clinical

Answer 13

acute so short-lasting

90% of children recover without complications

Question 14

Crescentic glomerularnephritis (rapid progressive glomerulonephritis)

causes

Answer 14

• Immune system directly attacks the glomerulus. The target is collagen IV
• Lungs also have collagen IV, so often lungs and kidney affected together

Question 15

crescentic glomerulonephritis (rapid progressive glomerulonephritis)

morphology

Answer 15

• IgG and C3 make up the deposits. Because it targets indiscriminately, crescent is not granular but solid
• Crescents eventually destroy Bowman’s space and lead to scarring, which permanently messes with the glomerulus’ ability to filter

Question 16

crescentic glomerulonephritis (rapid progressive glomerulonephritis)

clinical

Answer 16

• if untreated, patient will die within weeks/months

- Tx with immunosuppressants or renal transplant

Question 17

Acute Tubular Necrosis

Causes

Answer 17

Kidneys interact with a lot of blood and whatever is in the blood.

ATN is caused by ischemia and anything toxic (antifreeze, Gentamicin, CCL4)

Question 18

Acute Tubular Necrosis

morphology

Answer 18

If kidneys don’t get enough oxygen, the cells lining the tubule end up dying and falling off.

-As they die off, they accumulate and form the proteinaceous casts seen in ATN

Question 19

Urinary Tract Infection

Cause

Answer 19

• Gram negative bacteria

- They infect either by ascending the urinary tract or by getting in hematogenously

Question 20

urinary tract infection

predisposing conditions

Answer 20

Anything that helps the bacteria ascend

• females (shorter urethra)
• Outflow obstruction (urinary stones, strictures, pregnancy, tumors, BPH)

Question 21

Urinary tract infection

histopathology

Answer 21

• The bacteria will colonize a specific area of the UT so kidneys will appear normal and the lesions are focal
• leukocyte casts in urine
• small white abscesses on the subcapsular surface made of polys, dead tissue and liquefactive necrosis

(these casts and lesions are the aftermath of the battle between body and bacteria)

Question 22

urinary tract infection

clinical

Answer 22

Infection: body combats with inflammatory response which causes many of the symptoms (fever, chills, malaise, sweat)

Also area specific symptoms: frequency, painful urination (dysuria), bacteriuria and flank pain

Question 23

Wilms Tumor

Answer 23

• Wilms = the kid kidney tumor
• if there’s a gene association (90% sporadic) its wilm’s tumor 1 (WT1)
• it presents early (1-3 years) and contains mixed tissue types; components are developmental tissue (normal types of fetal tissue with immature elements)

Question 24

Renal Cell Carcinoma

who does it affect?

Answer 24

If kids have wilms, men over the age of 50 have renal cell carcinoma

Question 25

Renal Cell Carcinoma

gene defect

Answer 25

VHL gene: regulates angiogenesis

so will be a blood related symptom

Question 26

Renal Cell Carcinoma

histopathology

Answer 26

mass is yellow-orange

-colored by blood, hemorrhage and necrosis

Question 27

Renal Cell Carcinoma

clinical

Answer 27

Triad of presenting features:

• hematuria (blood related symptom)
• flank pain
• palpable mass

Question 28

Urothelial Carcinomas (transitional cell carcinomas)

Answer 28

pathogenesis:
-smoking (most bad stuff ends up in the bladder to be excreted)

histopathology:
-ranges from low grade (stay in the mucosa) to high grade (larger, solid, invasive)

Most aggressive ones will require radical surgery to remove malignant tissue