Sirenomelia and maternal chlamydia trachomatis infection: a case report and review.

Background: Sirenomelia is a lethal congenital anomaly, presenting with fusion of lower extremities and malformed perineum. The pathogenesis is unclear, and "defective blastogenesis" is the proposed mechanism. Chlamydia trachomatis (CT) is an obligate intracellular pathogen which reportedly invades placenta and may result in fetal demise. It has documented cytopathogenic effects, specifically, cellular disruption, tissue dysgenesis, and genomic instability. Case report: An infant with sirenomelia was born as a product of 30 weeks of pregnancy, which was normal except for a persistent maternal CT infection. The infant expired shortly after birth. Conclusion: Fetal invasion by CT, conceivably, may induce structural anomalies, such as sirenomelia by virtue of its cytopathic effects. We intend to draw attention to such a possibility by reporting this case. This association, however, is speculative and more cases of sirenomelia with CT positive mothers need to be described in order to make definite conclusions about such a relationship.