INTRODUCTION
Renal agenesis anomaly may affect
one or both kidneys and has an unknown aetiology.
Bilateral renal agenesis (BRA) occurs sporadically
but there is some evidence that genetic factors are
involved and it is important to screen both parents
and siblings. BRA can also occur as part of syndromes
such as VATER and branchio-oto-renal syndrome but
it is more commonly an isolated finding. BRA occurs
more frequently in males (2:1) and is incompatible
with life.
Unilateral renal agenesis (URA) is
much more common than BRA and is associated with
some ear and ureteral anomalies.
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ANTENATAL
Renal agenesis may not be immediately
apparent on ultrasound, but the bladder is never
seen and from 16 weeks gestation it becomes apparent
that there is reduced, or no liquor around the fetus.
Doppler studies can be used to distinguish BRA from
severe intrauterine growth retardation.
Severe oligohydramnios has devastating
consequences for the development of the fetal lungs.
If there is no liquor production the normal development
of the fetal lungs cannot occur. Amniotic fluid levels
are maintained by a balance between excretion of
fetal urine into the amnion and the swallowing of
fluid and its transfer to the mother via the placenta.
Thoracic compression and pulmonary
hypoplasia result from reduced amniotic fluid. This
compression of the embryo by the uterine wall and
lack of liquor may result in a sequence of abnormalities
called Potter syndrome these include severe talipes
and limb contractures from reduced movement. Potter's
facies include a square "parrot-beaked" nose,
hypomandibulosis, epicanthic folds, a rounded head,
wide set eyes, and low set ears. Visualisation of
other defects may be hampered by the squashed position
of fetus.
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POSTNATAL
BRA is incompatible with life. URA
may be asymptomatic but sometimes the other kidney
may be hypertrophied and more susceptible to damage
due its size.
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WEST MIDLANDS DATA
Information to follow
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