Development and teratology of urinary
system
24.4.2023 Anna Mac Gillavry
Pronephros: 4th week
Mesonephros: 4th - 10th week (6th - 12th week)
Metanephros: 5th to 9th week (12th week)
Segmented intermediate mesoderm
Unsegmented mesoderm Ureteric bud
A (metanephric system) B
T.W. Sadler, Langman's medical embryology, 12th edition
esonephros
Excretory tubule of mesonephros
T.W. Sadler, Langman's medical embryology, 12th edition
Metanephros
Allantois
Urorectal septum
Cloaca Ureteric bud
Hindgut
Mesonephric tissue y
Mesonephric duct
Metanephric blastema
Major calyx Metanephric blastema
Pelvis .
if,
Ureter Renal B pelvis
Collecting tubules
Outgrowing collecting tubules
Minor calyx
T.W. Sadler, Langman's medical embryology, 12th edition
Metanephric tissue caps
Cell clusters
.4SI
j Nephron
if ^ qi Renal
Collecting vesjc|e Bowman
A      tubule B C capsule
Distal convoluted tubule
Henle loop
Bowman capsule
Collecting tubules
Henle loop
Glomerulus
Distal convoluted tubule
Proximal convoluted tubule
Ascending and descending
limb of Henle loop
Glomerulus
Bowman's capsule
T.W. Sadler, Langman's medical embryology, 12th edition
Renal defects
• Renal agenesis: unilateral (1 in 1000 live births);
bilateral (1 in 3000 - 10000); 3:1 males to females; Potter sequence: anuria, oligohydramnios, pulmonary hypoplasia (Potter face)
• Renal displasia
- Multicystic displastic kidney
• Congenital polycystic kidney disease: autosomal recessive (1 in 5000)/ autosomal dominant (1 in 500 to 1000)
- group of cilliopathties Bardet-Biedl syndrome, Mackel-Gruber syndrom (lethal)
Renal defects
• Duplication of the ureter - splitting of the uretric bud
• Ectopic ureter - development of two uretric buds
• Supernumerary kidney
Abnormal location:
- pelvic kidney
- horseshoe kidney (1/600)
- unilatelar fused kidney
- accessory (suprenumeral) renal arteries -25 % of kidneys have 2 to 4 arteries
https://embryology.med.unsw.edu.au/em
Renal tumors
• Wilms tumor - affects children by 5 years of age incl. fetal period -
WAGR Syndrom (microdeletion on chromsome 11 WT1 and PAX6genes)
Wilms tumor Aniridia
Gonadoblastomas Retardation (intellectual disability) Denys-Drash syndrom
Bladder and urethra
Urogenital sinus:
- vesical part
- pelvic part
- phallic part
Mesonephric Allantois duct
Primitive urogenital sinus
Cloacal   Hindgut     UcTn^' Anorectal
a Septum oanal
lAmhranú ' Od I I Cl I
membrane A
Mesonephric Bladder duct
Perineal body
Pha"u-S" ÍJj^
y/jT^ Ureter
B
Urachal abnormalities
urachal fistula urachal cyst urachal sinus
Urachal fistula
Median umbilical ligament
Urinary bladder
Symphysis
Urethra
Urachal cyst
Urachal sinus
Figure 16.15 A. Urachal fistula. B. Urachal cyst. C. Urachal sinus.The sinus may or may ni tion with the urinary bladder.
T.W. Sadler, Langman's medical embryology, 12th edition
Ventral body wall deffects
T.W. Sadler, Langman's medical embryology, 12th edition
• Extrophy of the bladder: (1 in 50000)
• Extrophy of the cloaca: (1 in 200000)
CLOACAL EXSTROPHY
Hemibladder Prolapsed bowel
Tailgut
Omphalocele
Hemibladder Ileocecal area
PRIMARY OMPHALOCELE CLOSURE
Midline closure
Colostomy
COMPLETE aOSURE WITH COLOSTOMY AND VESICOSTOMY
Midline closure
I
- Colostomy
- Vesicostomy
COMPREHENSIVE COLORECTAL CENTER
Hemibladder
COMPREHENSIVE COLORECTAL CENTER
COMPREHENSIVE COLORECTAL CENTER
https://www.childrensmercy.org/departments-and<N^