Biamnial alpha fetoprotein concentration in twins, one with multiple malformations

Area of Science:

• Perinatology
• Prenatal Diagnosis
• Maternal-Fetal Medicine

Background:

• Twin pregnancies require careful monitoring for fetal development.
• Alpha-fetoprotein (AFP) levels in amniotic fluid are crucial markers for detecting fetal abnormalities.
• Elevated maternal serum AFP can indicate potential fetal defects.

Observation:

• Ultrasound at 18 weeks revealed dichorionic twins, one with significant malformations (abnormal skull, abdominal cystic area).
• The second twin appeared morphologically normal on ultrasound.
• Amniocentesis showed elevated AFP levels in the amniotic fluid of both fetuses.

Findings:

• Indirect immunofluorescence confirmed that the malformed twin had abnormally high AFP levels.
• Crucially, the healthy co-twin also exhibited pathological AFP levels within the same amniotic sac.
• This suggests a shared environment influencing AFP levels, even with disparate fetal health.

Implications:

• This finding highlights the potential for a single affected twin to skew diagnostic markers for a healthy sibling.
• It underscores the importance of considering the influence of one twin's condition on the other in prenatal diagnostics.
• Further research is needed to understand the mechanisms behind this cross-twin AFP elevation.