Outcome and etiologies of fetal megacystis according to the gestational age at diagnosis.
OBJECTIVE
To investigate the gestational age-specific outcomes and the different etiologies of megacystis diagnosed at screening ultrasound.


METHODS
A retrospective single-center study was conducted between 1989 and 2009. We identified all consecutive cases of megacystis prenatally diagnosed during routine ultrasound screening. Outcome, final diagnosis, and renal function were recorded.


RESULTS
Eighty-four patients were included. An isolated lower urinary tract obstruction was observed in 38/84 (45.2%), ureterovesical reflux in 9/84 (10.7%), an associated congenital abnormality in 32/84 (38.1%) and a normal bladder in 5/84 (6%). Increased gestational age at diagnosis was correlated with an increased rate of live born children (P < 0.01). No cases of megacystis diagnosed in the first trimester were born alive. When diagnosis of posterior urethral valves (PUV) was made in the third trimester, the ultimate survival rate was 11/13 (84.6%) compared with 3/12 (25%) for a diagnosis made in the second trimester (P = 0.02).


CONCLUSIONS
Lower urinary tract obstruction is the main etiology of megacystis. Megacystis can also be part of more complex malformations. Outcome of megacystis detected in the first trimester is poor. PUV detected in the third trimester had a better overall survival rate than PUV detected in the second trimester.
Gynecology and Obstetrics, AP-HP, Robert Debré Hospital, Paris, France; Gynecology and Obstetrics, AP-HP, Tenon Hospital, Paris, France.
Marie
M
Bornes
Emmanuel
E
Spaggiari
Thomas
T
Schmitz
Sophie
S
Dreux
Isabelle
I
Czerkiewicz
Anne-Lise
AL
Delezoide
Alaa
A
El-Ghoneimi
Jean-François
JF
Oury
Françoise
F
Muller
D000013:Congenital Abnormalities / Q000196:embryology; D004386:Duodenum / Q000002:abnormalities* / Q000000981:diagnostic imaging; D005260:Female; D005315:Fetal Diseases / Q000175:diagnosis / Q000000981:diagnostic imaging* / Q000209:etiology*; D005865:Gestational Age; D006801:Humans; D008297:Male; D011247:Pregnancy; D011256:Pregnancy Outcome; D011261:Pregnancy Trimester, First; D011379:Prognosis; D012189:Retrospective Studies; D016216:Ultrasonography, Prenatal; D001743:Urinary Bladder / Q000002:abnormalities* / Q000000981:diagnostic imaging; D014570:Urologic Diseases / Q000150:complications / Q000196:embryology; D014718:Vesico-Ureteral Reflux / Q000150:complications / Q000196:embryology