Module 9 : Fetal GU Pathology Flashcards
what do the ureteric buds become
- ureters
- renal pelvis
- calyces
- collecting tubules
what do the ureteric buds come from
- the wolffian ducts
what structure gives origin to the nephrons
- metanephros
what is the nephrons
- glomeruli
- loop of Henle
when does fetal urine production begin
- 11 weeks LMP
what produces amniotic fluid prior to 11 weeks
- produced by membranes and a bit by the lungs
where are the primitive kidneys located
- the pelvis
what does a failure of migration of the kidneys cause
- ectopic kidneys
what view is usually used to image the kidneys, what view is added when pathology is seen
- transverse
- sagittal
what is normal kidney length equal too
- gestational age
up to 20 weeks gestation what can mild fetal renal pelvis dilation be up to
5mm
from 20 weeks to term what can mild fetal renal pelvis dilatation be up to
8mm
what is the cloaca
- terminal end of the hind gut
- divided into two segments
where are the two compartments of the cloaca
- urinary
- rectal
what does the caudal end of the cloaca form
- urethra and bladder neck
what is the rest of the bladder formed by
- allantois which ends at the urachus
where do the mesonephric (ureters) enter the bladder
- posterior wall of bladder at trigone
what shape is the bladder in the transverse plane
- triangular
prior to 8 weeks LMP what state are the fetal genitals in
- ambiguous
when do normal male genitalia formed and why
- 8-10 weeks LMP
- when testosterone is present
what develops without the presence of testosterone
- female genitalia are developed due to maternal estrogens
up to what week can we not identify gender of baby
- 8 weeks
what sign means baby girl
- hamburger sign
what sign means baby boy
- turtle sign
+ needs to include penis
what is bilateral renal agenesis associated with
- GU abnormalities
- GI abnormalities
- cardiac abnormalities
- sirenomelia-mermaid syndrome
- teratogens
what are teratogens
- warfarin
- cocaine
- maternal diabetes (type 1)
why can unilateral renal agenesis be missed on ultrasound
- patients asymptomatic
- kidney will become enlarged because doing all the work
what is bilateral renal agenesis
- absent kidneys
what shape do the adrenals assume with bilateral renal agenesis
- discoid shape
- can be mistaken for kidneys
what 4 other sonographic features are present with bilateral kidney agenesis
- absent bladder
- oligohydramnios - anhydramnios
- small AC
- IUGR
what is potters syndrome
- refers to bilateral renal agenesis
what does potters sequence refer to
- consequence of severe oligohydramnios
physical appearance of potters syndrome
- pulmonary hypoplasia
- abnormal hand and foot positions
- facial anomalies
- IUGR
what are the facial anomalies of potters syndrome
- beaked nose
- low set ears
- prominent epicanthic folds
- hypertelorism
what is one tool that can help us diagnose unilateral kidney agenesis
- color doppler
- only one renal artery
sonographic appearance of adrenals with renal agenesis
- laying down adrenal gland
- adrenals can be mistaken for kidney as they occupy the space where the kidneys should be
what is the definition of hydronephrosis
- distention of the renal pelvis and calyces with urine due to obstructions
how many renal abnormalities will be hydro and how many are associated with syndromes
75%. 20%
is hydro more commonly unilateral or bilateral
- unilateral
three causes of hydro
- obstruction
- reflux
- ureterocele
4 things to determine when assessing hydro
- bilateral vs unilateral
- degree of hydro
- level of obstruction
- evaluate for other abnormalities
3 levels of obstruction for hydro
- hydronephrosis only/only kidneys are dilated
- dilated ureters with hydro
- dilated bladder and keyhole appearance
hydro only / only kidneys are dilated
- UPJ obstruction
dilated ureters with hydro
- UVJ obstruction
dilated bladder and keyhole appearance
- PUV (posterior urethral valve obstruction)
- typically males
grade I hydro
- renal pelvis only
- pelviectasis
grade II hydro
- renal pelvis and calyces visible
grade III hydro
- renal pelvis and calyces dilated
grade IV hydro
- parenchymal thinning
+ when a nephrostomy tube needs to be put in
what is the most common urinary obstruction in neonates
- UPJ (ureteropelvic junction) obstruction
characteristics of unilateral UPJ obstruction
- normal bladder and amniotic fluid
characteristics of bilateral UPJ obstruction
- oligohydramnios
- hydronephrosis of varying degrees
characteristics of severe UPJ obstruction
- renal parenchymal may be destroyed
sonographic difference between bilateral UPJ obstruction and duodenal atresia
- they will be on different levels in the transverse plane
3 pitfalls of UPJ
- extra renal pelvis
- prominent renal veins
- reflux
what is an extra-renal pelvis
- normal renal pelvis is outside of the kidney
- extra renal pelvis is under 1.5cm it may mmimic a small hydronephrosis
what is reflux
- urine is retrograding from the bladder up, the ureter into the kidney
- transient = kidney dilation comes and goes
what is a UVJ obstruction usually caused by
- due to duplicated collecting system with an ectopic ureter location from the upper pole of the kidney
UVJ on ultrasound
- dilated upper pole of the kidney with a dilated tortuous ureter
- lower pole of the kidney is normal
what structure may the ureter may mimic
- bowel
how to differentiate between bowel and ureter
- bowel is medial in the abdomen
- ureter would be lateral in the abdomen
what is an ectopic ureter associated with
- ureterocele in bladder
definition of ureterocele
- cystic dilation of the intravesicular portion of the ureter
what is a ureterocele associated with
- dilation of the upper pole of the kidney in duplicated collecting system
definition of a PUV
- PUV membranes that occur in the prostatic urethra of a male fetus that obstruct the retrograde flow of urine
sonographic appearance of PUV
- large distended bladder
- oligohydramnios
- hydronephrosis
- males only
three sonographic appearances of bladder rupture
- ascites apparsa
- bladder wall appears thickened
- moderate uretero-pelvicalyceal dilatation
what might PUV be a precursor to
- prune belly syndrome (eagle-barrette syndrome)
what is eagle- Barrett syndrome
- undescended testicles (cryptorchidism)
characteristics of eagle - Barrett syndrome
- very large bladder with abdominal distention
- lack of abdominal musculature
+ after birth abdomen looks like prune form stretching - ureters may be tortuous and dilated
- kidneys
+ normal
+ hydronephrotic
+ dysplastic
what is bladder exstrophy associated with
- cloacal exstrophy
what is a cloacal exstrophy
- lower abdominal wall defect
- involving the lower GI tract, bladder and genitalia
what is the OEIS complex
- omphalocele
- exstrophy of bladder
- imperforate anus
- spinal abnormalities
4 renal cystic disease
- infantile polycystic kidney disease (ARPKD)
- adult polycystic kidney disease (ADPKD)
- muulticystic dysplastic kidney kidney
- obstructive cystic renal dysplasia
what is infantile polycystic kidney disease
- aka IPKD / ARPKD
- autosomal recessive disorder
- primary defect of collecting ducts
- multiple small cysts under 1-2mm ( to small to see on sonography )
what is the sonographic appearance of IPKD
- GROSSLY ENLARGED ECHOGENIC KIDNEYS
- but retain reniform shape
- absent bladder
- severe oligohydramnios
is IPKD unilateral or bilateral
- always bilateral
3 diagnostic criteria of IPKD
- bilateral enlarged echogenic kidneys
- oligohydramnios
- absent bladder
4 subtypes of IPKD
- perinatal
- neonatal
- infantile
- juvenile
why do IPKD kidney appear echogenic
- all of the interfaces between the small cysts
what 3 syndromes is IPKD associated with
- mucked - gruber syndrome
- Roberts syndrome
- trisomy 13
three sonographic signs of meckel gruber
- IPKD
- polydactyl
- encephalocele
3 sonographic signs of reverts syndromes
- IPKD
- phocomelia (hands and feet attached to truck with single bone)
- cleft palate
DDX of IPKD
- benign glomerulosclerosis
what is benign glomerluosclerosis
- large echogenic kidneys
- echogenic pyramids and normal fluid
- diagnosed under a microscope
characteristics of adult polycystic kidney disease
- aka ADPKD, APKD
- rarely seen in antenatal sonography
- fetus is assessed if parent has disease
sonographic appearance of APKD
- enlarged kidneys with cyst
- may be hyperehoic
- amniotic fluid is normal
- fetal bladder is present
- scan parents as well
characteristics of multi cystic dysplastic kidney
- aka MCDK
- multiple cystic lesions which due not communicate
- kidneys lose reniform shape
what is prognosis of MCKD
- unilateral is good prognosis
- bilateral is rare
+ fatal due to lack of amniotic fluid
+ associated with potters sequence
does MCKD have a genetic predisposition
- no
two types renal tumors
- nephroblastoma
- mesoblastic nephroma
what is a nephroblastoma
- aka wilms tumor
- solid mass
- not commonly identified in utero
what is a mesoblastic nephroma
- most common congenital renal tumor
2 adrenal pathologies
- neuroblastoma
- hemorrhage
6 pathologies of genitalia
- hydroceles (male)
- cryptorchidism (male)
- hydrometrocolpos (female)
- ambiguous genitalia
- x linked syndromes
+ turners, noonans, hemophilia - ovarian cysts (female)
