India.

Case report

This is a case of monochorionic diamniotic twin pregnancy in a primigravida who was scanned at our department at 13 weeks of gestation.  We did not detect any abnormality at first twin, except of the reverse flow in ductus venosus. The second twin was affected, the ultrasound examination revealed following findings:

• Pentalogy of Cantrell  with following components:

• Alobar holoprosencephaly with orbital hypotelorism and proboscis 
• Cystic hygroma
• Hydrops

Comment

Ectopia cordis is a rare anomaly, incidence is less than 0.1:10.000. Combined finding of holoprosencephaly and ectopia cordis is a very rare finding. We have found only one case with the similar findings, described in the literature [1].

Extracranial midline anomalies are commonly associated with holoprosencephaly (52 %). Associated anomalies usually include meningomyelocele, renal dysplasia, omphalocele, esophageal atresia and heart defects [1].

In our case, the associated anomaly was ectopic heart with other findings consistent with Pentalogy of Cantrell. Possible etiology of Pentalogy of Cantrell is a failure of fusion of lateral folds in thorax with failure of development of transverse septum of diaphragm.

Associated anomalies with Pentalogy of Cantrell are usually cleft lip and palate and encephalocele [2]. Prognosis for isolated Pentalogy of Cantrell depends on the severity of the findings, but it's usually fatal. Prognosis with associated alobar holoprosencephaly is fatal.

References:

1. P.J. Taipale, T. Krista,I. Alafuzof. Prenatal diagnosis of holoprosencephaly and ectopia cordis in a twin at 12 weeks’ gestation. Ultrasound Obstet Gynecol 2003; 21: 198–204.
2. M.D. Rivka Carmi1, Joann A. Boughman.Pentalogy of Cantrell and associated midline anomalies: A possible ventral midline developmental field.Pentalogy of Cantrell and associated midline anomalies: A possible ventral midline developmental field. American Journal of Medical Genetics, 1992; 42: 90–95.