Chapter 64 Fetal Urogenital system Flashcards
of the 3 sets of ecretory organs that develop in the embryo, which one remains as permanent kidneys?
metanephros
first pair of kidneys that are rudimentary and nonfunctional–
pronephros
second pair of kidneys that function for a short time during early fetal period. Degenerate after being replaced by metanephros
mesonephros
urine formation begins toward the end of the ____
1st trimester
kidneys do not need to function as waste filtration because:
placenta eliminates waste from fetal blood
___% of adult kidneys have 2-4 renal arteries
25%
the kidneys initially lie:
close together in the pelvis
normal kidney migration is complete by:
9th week
external genitalia are fully differentiated by:
12 weeks
kidneys are evaluated on:
anatomy
texture
size
by 12 weeks ___% of kidneys may be imaged
86%
kidneys may be seen as early as ___ weeks with TVS
9 weeks
fetal kidneys and bladder are seen by ___
13 weeks
overall echogenicity of kidneys decrease at about:
15 weeks
you are able to distinguish renal cortex from medulla by:
25 weeks
the ____ of the kidney closely correlates with gestational age
length
round anechoic structure centrally located in the pelvis:
bladder
bladder usually takes at least ____ to fill and empty
30 minutes
duplication of the renal collecting system is common and usually happens in
females
if kidneys are not seen sonographically, look in the
pelvis
kidney should be seen at the same level as the
spine
not visualizing the bladder indicates:
a severe renal anomaly, especially when accompanied with oligohydramnios
dilated ureters
hydroureters
hydroureters are visualized as
tortuous cystic masses
renal malformations are divided into 2 categories:
- congenital
2. obstructive
absence of 1 or both kidneys
renal agenesis
occurs when ureteric buds fail to develop or they degenerate
renal agenesis
these two things have been found to be related to renal agenesis:
- cocaine use
- diabetes
one functioning kidney
unilateral renal agenesis
unilateral renal agenesis prognosis
excellent survival rates
sonographic appearance of unilateral renal agenesis
remaining kidney will be enlarged(complensatory hypertrophy)
unilateral renal agenesis; the bladder is:
visualized, normal
bilateral renal agenesis is referred as
Potter’s syndrome
bilateral renal agenesis is lethat due to:
- renal insufficiency
- pulmonary hypoplasia
potter’s syndrome is characterized by what findings?
- oligohydramnios
- renal failur/bilateral renal agenesis
- abnormally positioned extremeties
- flat nose
- recessed chin
- abnormal ears
- wide-set eyes
sonographic findings of bilateral renal agenesis
- adrenal gland may mimic absent kidney
- severe oligohydramnios
- absent bladder
- absent kidneys or renal arteries
- small thorax
horseshoe kidney forms when ____ poles of kidney fuse while they’re in the pelvis
inferior
horseshoe kidney is more common in _____
2-3 times more common in males
occurs when kidney lies outside of its normal position
renal ectopia
associated anomalies with renal ectopia:
- skeletal
- cardiovascular
- gynecologic
- GI
abnormally located kidney appears:
- small
- rotated/oblique
- typically lies superior to bladder(if found in pelvis)
this causes urine to drain from the bladder to the umbilicus:
urachal fistula
if only a small part of the bladder lumen persists while the urachus forms, a _____ forms
urachal cyst
if a large part of the bladder lumen persists while the urachus forms, a _____ forms
patent urachus
used to describe renal diseases other than renal agenesis that result in renal failure and facial/structural abnormalities caused by oligohydramnios
potters sequence/classification
IPKD/ARPKD leads to overall ____ of kidneys
enlargement
sonographic appearance of IPKD/ARPKD
- englarged, hyperechoic kidneys
- small/absent bladder
- oligohydramnios
- renal failure
IPKD/ARPKD may occur with:
- Meckel-gruber syndrome
- trisomy 13
multiple, smooth-walled, nonfunctioning, noncommunicating cysts on the kidney(s)
MCDK
most common form of renal cystic disease in childhood
MCDK
MCDK is linked to:
maternal diabetes
MCDK more often occurs in ____
males
most cases of MCDK are __-lateral
unilateral
the bladder with MCDK appears:
normal
MCDK is thought to occur from:
- early obstruction
- abnormal development of metanephric mesoderm & ureteric bud
bilateral MCDK prognosis is _____
lethal
sonographic appearance of bilateral MCDK
- oligohydramnios
- absent bladder
unilateral MCDK, the contralateral kidney will be
enlarged
most common hereditary renal cystic disease
ADPKD
sonographic appearance of ADPKD
- kidneys are symmetrically enlarged and echogenic, or normal
- normal AFI
- almost always bilateral
- bladder present
if obstruction occurs early:
multicystic kidney may develop
if obstruction occurs 1st or 2nd trimester:
cystic dysplasia may result
if obstruction occurs late:
produces hydronephrosis
dilation of the renal pelvis and calyces
pelviectasis
dilation of the renal pelvis without dilation of the calyces
pylectasis
pelviectasis will occur in:
hydronephrosis
most common fetal anomaly
hydronephrosis
unilateral hydronephrosis usually occurs from obstruction at the ____
UPJ
dilation of the renal pelvis due to blockage of urine at some junction in the urinary system
hydronephrosis
you find an abnormal intrapelvic AP diameter measurement, this is suggestive of:
hydronephrosis
mild pylectasis is associated with ______
down syndrome
most common reason for hydronephrosis in the neonate
UPJ obstruction
UPJ & UVJ is more common in
males
UPJ sonographically, collection of anechoic urine located medially within the renal pelvis communicating with the calyces, may appear ____ shaped
bullet
UVJ obstruction leads to :
megaureter
majority of the causes for megaureter is due to
distal portion of ureter being aperistalic
posterior urethral valve obstruction results in
- hydronephrosis
- dilation of bladder and posterior urethra
most common urethral anomaly
posterior urethral valve obstruction (PUV)
most common cause of infravesical obstruction in males
posterior urethral valve obstruction
severely thickened bladder wall with dilated posterior urethra is referred to as the _____ sign
key-hole sign
key-hole sign occurs with
Posterior Urethral Valve obstruction (PUV)
congenital defect resulting in obstruction of the anterior urethral valves, occurs in males
anterior urethral valve obstruction
Prune belly syndrome is also referred as:
Eagle-Barret syndrome
characterized by 3 things:
- cryptorchidism
- agenesis/hypoplasia of abdominal wall muscles
- dilation of collecting system
prune belly syndrome
prune belly syndrome is seen mostly in
males
prune belly syndrome may lead to
renal dysplasia and pulmonary hypoplasia
cystic dilation of the bladder segment of the distal ureter
ureterocele
Ureterocele is more common in _____ if system is duplicated
females
Ureterocele is more common in _____ if system is normal/not duplicated
males
most common renal tumor
mesoblastic nephroma
mesoblastic nephroma is referred to as
hamartoma
malignant tumor of the adrenal gland
neuroblastoma
neuroblastoma usually presents in the ___ trimester
3rd trimester
Neuroblastoma is likely to metastasize to the liver in utero if:
the mass is solid
accumulation of fluid around the testicle(s)
hydrocele
hydroceles have been reported with
hydrops
testes remain near deep inguinal rings until ____ weeks
28 weeks
cryptorchidism is associated with risk of:
- torsion
- cancer
abnormal opening of the urethra, birth defect in boys
hypospadias
ambiguous genitalia typically result from:
chromosomal defects or abnormal hormone levels
inability to delineate fetal gender
ambiguous genitalia
rare, have both ovaries and testes
true hermaphroditism
most fetuses with true hermaphroditism will have ____ karyotype
normal, some are mosaics
female pseudohermaphrodites has a ___ karyotype
46, XX
most common cause of female pseudohermaphrodites is
congenital virializing adrenal hyperplasia
congenital virializing adrenal hyperplasia causes
masculinization of external genitalia
male pseudohermaphrodites has a ____ karyotype
46, XY
chromosomal anomalies associated with ambiguous genitalia:
- trisomy 13
- triploidy
- certain deletions
- translocation
most common cystic mass in female fetus
fetal ovaria cyst
obstruction of uterus and vagina
hydrometrocolpos
hydrometrocolpos results from
- imperforate hymen
- atresia of vagina/cervix