Prenatal ultrasound diagnosis of duplication gallbladder: a multicenter study.

BACKGROUND Gallbladder duplication is a rare anatomic anomaly characterized by the presence of an accessory gallbladder. OBJECTIVE To appraise the prevalence and significance of prenatal diagnosis of duplication of gallbladder in a multicenter study. METHODS This was a multicenter case series with literature review. Clinical records of all consecutive pregnant women with a prenatal diagnosis of duplication of gallbladder, who were referred to our Centers were included in this study. The diagnosis of duplication of gallbladder was based on the evidence of double gallbladder in the standard abdominal circumference plane using grey scale. Postnatal magnetic resonance cholangiopancreatography (MRCP) 3D and postnatal neonatal abdominal ultrasound scan were offered soon after birth to confirm the diagnosis of double gallbladder. The systematic review was conducted using electronic databases from inception of each database through December 2019. RESULTS Five studies, including a total of seven cases, were identified as relevant and included in the systematic review. Gestational age at diagnosis ranged from 20 to 32 weeks of gestation. Associated findings were reported in only one case, where the fetus presented with a left-sided gallbladder, and bilateral renal agenesis with Potter sequence. None of the included cases reported abnormal karyotype. Our cases series included nine cases (0.03%) of double gallbladder with postnatal confirmation, with an overall incidence of this anomaly of 0.03%.Associated findings were reported in only two cases, one with IUGR and omphalocele, that opted for I-TOP, and one with single umbilical artery. Except for the I-TOP, neonatal outcome was favorable in all cases. CONCLUSIONS Duplication of the gallbladder is a very rare malformation with only seven cases reported in the literature diagnosed prenatally. This anomaly is not associated with abnormal karyotype, and the neonatal outcome is favorable if there are no other associated abnormalities.