Ped. Dev. Cystic and Neoplastic KD

Question 1

Renal agenesis and hypoplasia

Answer 1

agenesis failure of metanephric diverticulum to develop

hypoplasia: congenitally small kidney bc it degenerates early

Question 2

Renal dysplasia

Answer 2

abnormal metanephric tissue differentiation of the kidney tissue with cysts and heterotopic tissues
(island of cartilage on histo slides)

Question 3

renal ectopia

Answer 3

failure of kidney to rise out of the pelvis or rotate medially
–> ureteral obstruction

*ectopia = out of place

Question 4

Horshoe kidney

Answer 4

kidneys are fused - often ectopic and fail to medially rotate
- increased incidence of urolithiasis

Question 5

classification of cystic renal disease

Answer 5

1. acquired (just happen)
2. genetic
   - ADPKD
   - ARPKD
   - VHL
3. developmental
   - multicystic Dysplastic kidney

Question 6

Autosomal dominant AD-PKD

Answer 6

• major cause of End stage renal disease
• mut in PKD1 (90%) on ch16
• 100% penetrance

Question 7

AD-PKD associated diseases

Answer 7

wall abnormalities:
hepatic cysts 80%
diverticulosis 80%
mitral valve prolapses 25%
cerebran aneurysm 5-30%

Question 8

Autosomal Recessive PKD

Answer 8

Infantile

• due to mut to PKHD1 on ch 6
• HTN in first few years (weird)
• cant concentrate urine/renal insufficiency

Question 9

Most common cause of an abdominal mass in the newborn

Answer 9

**know

multicystic dysplastic kidney

• affected kidney is nonfunctional,asymptomatic and will go away but parents want us to take it out.

Question 10

multicystic dysplastic kidney results from what?

Answer 10

Abnormal induction of the metanephric blastema by the ureteral bud

Question 11

Congenital mesoblastic nephroma

Answer 11

3% of pediatric renal tumors

- most common kidney tumor at birth -6 months

Question 12

Most common malignant kidney tumor of childhood 4-6

Answer 12

80% Wilms Tumor (nephroblastoma)

- resect or chemo

Question 13

Wilms tumor

• aka?
• describe histology

Answer 13

aka Nephroblastoma

• classic histology is triphasic
  1. blastemal (small round blue cells)
  2. epithelial (tubules)
  3. stromal (fibroblastic)

Question 14

What is a bad histological feature for wilms tumor?

- describe

Answer 14

anaplasia (looks like a kabooki mask)

• large, hyperchromatic cells, bizzarre mitoses

Question 15

Beckwith Weidemann syndrome

Answer 15

• babies with gigantism, macroglossia, abdominal wall defects
• due to imprinting abnormality

Question 16

WAGR syndrome

Answer 16

phenotype:
Wilms tumor
Aniridia (absence of iris)
Genitourinary malformation
Retardation (mental)