ultrasound diagnosis of fatal anomalies

ECHOGENIC KIDNEYS
Echogenic Kidneys
Definition and clinical significance: The kidneys
are more echogenic than the liver. This may be a
normal finding, or may be the first sign of nephrotic
syndrome or other renal anomalies. A
case associated with cytomegalovirus infection
has been reported. Benacerraf published 19
cases, in which there was a normal postnatal
outcome in only four (21%). Five (26%) died and
had either infantile polycystic kidneys or multicystic
renal dysplasia. In two cases, oligohydramnios
only developed after 24 weeks; in one
case, partial trisomy 10 was found.
Associated syndromes: Infantile polycystic kidneys,
Meckel–Gruber syndrome, trisomy 13,
Perlman syndrome, cystic renal dysplasia, Beckwith–Wiedemann
syndrome.
Ultrasound findings: The volume of the kidneys
is increased (above the 95th percentile), with a
high echogenicity. If the renal function is affected,
oligohydramnios or anhydramnios are
found and the bladder is hardly filled. In some
cases, oligohydramnios may even be detected at
15 weeks.
Prognosis: The decisive prognostic criterion is
renal function, determined by the extent of
amniotic fluid. Cases of severe oligohydramnios
have a poor outcome.
References
Carr MC, Benacerraf BR, Estroff JA, Mandell J. Prenatally
diagnosed bilateral hyperechoic kidneys with normal
amniotic fluid: postnatal outcome. J Urol 1995;
153: 442–4.
Choong KK, Gruenewald SM, Hodson EM. Echogenic
fetal kidneys in cytomegalovirus infection. J Clin Ultrasound
1993; 21: 128–32.
Lilford RJ, Irving HC, Allibone EB. A tale of two prior
probabilities: avoiding the false positive antenatal
diagnosis of autosomal-recessive polycystic kidney
disease. Br J Obstet Gynaecol 1992; 99: 216–9.
Nyberg DA, Hallesy D, Mahony BS, Hirsch JH, Luthy DA,
Hickok D. Meckel–Gruber syndrome: importance of
prenatal diagnosis. J Ultrasound Med 1990; 9: 691–6.
Vintzileos AM, Egan JF. Adjusting the risk for trisomy 21
on the basis of second-trimester ultrasonography
[review]. Am J Obstet Gynecol 1995; 172: 837–44.
Wisser J, Hebisch G, Froster U, et al. Prenatal sonographic
diagnosis of autosomal-recessive polycystic
kidney disease (ARPKD) during the early second
trimester. Prenat Diagn 1995; 15: 868–71.
Fig. 10.6 Echogenic kidneys. Dilation of the renal
pelvis and fetal ascites in a fetus with trisomy 9.
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