Renal embryology Flashcards
Oligohydramnios
Bilateral agenesis (incompatible with life)
Lung hypoplasia, flat face with low set eats, and developmental defects of extremities
Potter sequence of bilateral agenesis
Noninherited, congenital malformation of the renal parenchyma characterized by cysts and abnormal tissue (e.g. cartilage)
Dysplastic kidney (usually unilateral in real life, but bilateral on step 1)
inherited defect –> bilateral enlarged kidneys with cysts in renal cortex and medulla
Polycystic kidney disease (PKD)
PKD that presents in young adults with HTN (inc renin), hematuria, and worsening renal failure
autosomal dominant PKD
Mutations in APKD1 or APKD2 –> development of cysts in kidneys over time
AD PKD
AD PKD is associated with three things
berry aneurysm (cause of death),
hepatic cysts,
mitral valve prolapse
Inherited (AD) defect –> cysts in medullary collecting ducts –> parenchymal fibrosis resulting in shrunken kidneys and worsening renal failure
Medullary cystic kidney disease
Conjoined kidneys usually connected at the lower pole; most common kidney anomaly
horseshoe kidney
What does horseshoe kidney get stuck on during embryogenesis?
IMA
absence of kidney formation
renal agenesis
Leads to hypertrophy of existing kidney –> hyper filtration increased the risk of renal failure later in life
unilateral agenesis
PKD that presents in infants with worsening renal failure, HTN, & potter sequence
Autosomal recessive PKD
AR PKT is associated with
congenital hepatic fibrosis, hepatic cysts –> portal hypertension
“kidney” that exists till week 4 of fetal life, then degenerates
Pronephros
functions as interim kidney for 1st trimester; laster contributes to male genital system
Mesonephros
permanent kidney; first appears in 5th week of gestation; nephrogenesis continues through 32-36 weeks of gestation
Metanephros
Derived from caudal end of mesonephros; gives rise to ureter, pelvises, calyces, and collecting ducts; fully canalized by 10th week
ureteric bud
Ureteric bud interacts with this tissue; interaction induces differentiation and formation of glomerulus through to DCT
Metanephric mesenchyme
last to canalize - most common site of obstruction (hydronephrosis) in the fetus
Ureteropelvic junction
aberrant interaction between these two tissues may result in several congenital malformations of the kidney
ureteric bud, metanephric mesenchyme
Oligohydramnios –> compression of fetus –> limb deformities, facial deformities, and pulmonary hypoplasia (COD)
Potter’s syndrome
Babies who can’t Pee in utero develop
Potter’s
Causes of Potter’s syndrome
ARPKD,
posterior urethral valves
bilateral renal agenesis
genetic condition associated with horseshoe kidney
Turner syndrome
inferior poles of both kidneys fuse –> trapped under IMA (remain low in abdomen), but kidney functions normally
Horseshoe kidney
Abnormal interaction between ureteric bud and metanephric mesenchyme –> nonfunctional kidney consisting of cats and connective tissue
Multicystic dysplastic kidney
Unilateral multicystic dysplastic kidney
generally asymptomatic with compensatory hypertrophy of contralateral kidney
diagnosis of multi cystic dysplastic kidney
usually prenatally via ultrasound
