Fetal Megacystis: Experience of a Single Tertiary Center in Switzerland over 20 Years

Abstract

Objectives: Megacystis (MC) is rare and often associated with other structural and chromosomal anomalies. In euploid cases with early oligohydramnios, prognosis is poor mainly due to pulmonary hypoplasia and renal damage. We report our experience of the past 20 years. Methods: A retrospective review of cases with prenatally diagnosed MC was performed. Complete prenatal as well as postnatal medical records from 1989 to 2009 were reviewed focusing on diagnostic precision, fetal interventions [vesicocentesis (VC), vesicoamniotic shunt (VAS)], short- and long-term outcome, and potential prognostic factors. Results: 68 cases were included. Follow-up was available in 54 cases (9 girls and 45 boys including 3 cases with aneuploidy). We found 39 isolated MC at sonography (5 girls and 34 boys). 24 fetuses with isolated MC underwent VC and VAS at 19.6 ± 6.3 and 20 ± 4.9 weeks of gestation, respectively. Survival rate was higher in male than in female fetuses (51 vs. 33%). Renal problems occurred in 4/14 prenatally treated fetuses and in 1/10 when cases with prune belly syndrome (PBS) were excluded from the analysis. Conclusions: Our study shows that a careful selection of cases with MC excluding fetuses with PBS and early treatment has still the potential to improve outcome.

Prenatal diagnosis of LUTO: improving diagnostic accuracy

“…Previous studies have investigated fetal urine production according to gestational age in healthy fetuses without reporting fetal bladder dimensions. Miscellaneous criteria have been used in the literature for defining megacystis in the second and third trimesters, ranging from bladder length > 99 th percentile for gestational age in the absence of a nomogram, to the most commonly used definition of fetal bladder failing to empty during a period of 45 min. There has not yet been a prospective study published that has elucidated normal bladder dimensions during the second and third trimesters of pregnancy and defined a threshold for pathological enlargement.…”

New Insights into the Genetics of Fetal Megacystis: ACTG2 Mutations, Encoding γ-2 Smooth Muscle Actin in Megacystis Microcolon Intestinal Hypoperistalsis Syndrome (Berdon Syndrome)

“…Prenatal diagnosis of fetal megacystis represents a diagnostic challenge [30,31]. In the first trimester, the longitudinal bladder diameter (>7 mm) appears to be a useful sonographic marker for fetal aneuploidy [32].…”

Evaluation of Fetuses Diagnosed With Megacystis During Prenatal Period

“…The fetal bladder can easily be visualized as a round or oval structure without echogenicity between two umbilical arteries in the pelvis by routine ultrasonography (1). Although urogenital anomalies are common, megacystis (MC) is very rare and its incidence is reported to be 0.06% (2,3). It has been reported that several genetic, environmental and teratogens may be responsible for urinary tract abnormalities (4).…”

“…The longitudinal diameter of the normal bladder in the first trimester is usually <6mm (2). The diagnosis of early-onset MC is made when the bladder is detected more than 7mm in the first-trimester ultrasonography.…”