GU

Question 1

Fetus begins to make urine

Answer 1

9w

Question 2

Production of AF after 14w

Answer 2

2/3 of AF is produced by fetal urination, 1/3 from pulmonary fluid

Question 3

If minimal hydro dx’d before 24 wks, __% resolution

Answer 3

90

Question 4

Minimal fetal hydronephrosis - aneuploidy risk

Answer 4

Slight incr risk of T21, T13, Turner’s

Question 5

MCC of significant neonatal hydronephrosis

Answer 5

UPJ obstruction

Question 6

Grade 0 Hydronephrosis

Answer 6

Intact renal complex, nl renal parenchymal thickness

Question 7

Grade 1 Hydronephrosis

Answer 7

Slight splitting of pelvis and calices, nl renal parenchymal thickness

Question 8

Grade 2 Hydronephrosis

Answer 8

Evident splitting of pelvis and calices, nl renal parenchymal thickness

Question 9

Grade 3 Hydronephrosis

Answer 9

Wide splitting of pelvis and calices, nl renal parenchymal thickness

Question 10

Grade 4 Hydronephrosis

Answer 10

Further splitting of pelvis and calices, reduced renal parenchymal thickness

Question 11

Ddx of minimal fetal hydronephrosis

Answer 11

Extrarenal pelvis, prominent renal veins crossing over renal pelvis, VUR

Question 12

2nd trimester cutoff for hydronephrosis

Answer 12

4 mm

Question 13

3rd trimester cutoff for hydronephrosis

Answer 13

7 mm

Question 14

Primary causes of UPJ

Answer 14

Intraluminal valves, polyps, congenital mucosal folds, muscular hypertrophy, aberrant crossing vessels

Question 15

Secondary causes of UPJ

Answer 15

VUR or more distal obstruction

Question 16

VUR recurrence risk

Answer 16

high familial incidence, thought to be AD with reduced penetrance

Question 17

UPJ obstruction before 10w, vs 2nd trimester

Answer 17

Before 8-10w => severe dysplastic changes -> multicystic dysplastic kidney
2nd trim -> pelvicaliceal dilation

Question 18

Frequency & cause of polyhydramnios in UPJ obstruction

Answer 18

25-33% of cases, possibly due to impaired renal concentrating ability -> increased urine output

Question 19

UPJ obstruction - assoc anomalies

Answer 19

horseshoe kidney, MDK, CDH, hydrocephalus, CCAM

Question 20

UPJ obstruction - good prognosis

Answer 20

urine Na < 100 meq/L, Cl < 90 meq/L, osmolarity < 210 mosm/L, Ca < 2 mmol/L, PO4 < 2 mmol/L, B2-microglobulin < 4-6 mg/L

Question 21

DDx of UPJ obstruction w/ bilateral hydronephrosis

Answer 21

Supravesical obstruction - Bilateral UPJ obstruction, bilateral ureterovesicular obstruction
Infravesical obstruction - PUV, urethral atresia, obstruction ureterocele
VUR (bilateral, usually high-grade)
Prune-belly syndrome
Megacystis-microcolon-hypoperistalsis syndrome

Question 22

DDx of UPJ obstruction w/ unilateral hydronephrosis

Answer 22

UPJ obstruction
Ureterovesical junction obstruction
Multicystic dysplastic kidney
Megaureter (nonobstructing, nonrefluxing; may be bilateral)
Renal duplication (may be bilateral)
Dilated loop of bowel

Question 23

UPJ recurrence risk

Answer 23

Common, but usually sporadic

Question 24

MCC of bladder outlet obstruction in males

Answer 24

Posterior urethral valves

Question 25

MCC of bladder outlet obstruction in females

Answer 25

Urethral atresia

Question 26

Def of enlarged bladder

Answer 26

> 3 cm length in 2nd trim, > 5 cm in 3rd trimester

Question 27

Def of thickened bladder wall

Answer 27

> 2 mm

Question 28

BOO - characteristic presentation

Answer 28

dilated bladder, bilateral hydroureteronephrosis

Question 29

DDx of BOO

Answer 29

Supravesical obstruction - Bilateral UPJ obstruction, bilateral ureterovesicular obstruction Infravesical obstruction - PUV, urethral atresia, obstruction ureterocele VUR (bilateral, usually high-grade) Prune-belly syndrome Megacystis-microcolon-hypoperistalsis syndrome

Question 30

BOO - aneuploidy risk

Answer 30

12% - T13, T18, T21

Question 31

Ectopic ureterocele - aneuploidy risk

Answer 31

No known assoc with chromosomal abnl

Question 32

Ectopic ureterocele - recurrence risk

Answer 32

Occurs sporadically, no increased risk of recurrence

Question 33

What is ectopic ureterocele?

Answer 33

Ureterocele = cystic dilatation that occurs at the distal end of the ureter, at its jxn with the bladder. Ureteral orifice is located in an ectopic position, usually distal to the trigone. It is a rare cause of BOO, as the ureterocele can prolapse into the urethra.