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A fetus with hemifacial microsomia and sirenomelia. The same mesodermal defect spectrum?
Jaime Asael López-Valdez1, Higinio Estrada-Juárez, Elsa Romelia Moreno-Verduzco
1Department of Genetics, Centenario Hospital Miguel Hidalgo, Aguascalientes, Ags, México.
Fetal and Pediatric Pathology
|May 31, 2012
Summary
Sirenomelia, a severe caudal malformation, may be linked to hemifacial microsomia, suggesting a shared mesodermal dysplasia spectrum. Further research is needed to understand genetic and environmental factors in embryonic development.
Area of Science:
- Developmental Biology
- Medical Genetics
- Teratology
Background:
- Sirenomelia is a rare and severe congenital anomaly affecting the caudal (tail) region of the human body.
- Its exact cause remains largely unknown, with theories including a primary defect in blastogenesis or classification within broader syndromes like VACTERL association.
Observation:
- A fetus presented with a complex set of malformations including cleft lip and palate, microtia, cardiac, renal, and intestinal defects, radial aplasia, and sirenomelia.
- Genetic analyses, including karyotype, chromosomal breakage studies, and SHH gene sequencing, yielded normal results.
Findings:
- The co-occurrence of cephalic (head), midline-paramedial, and caudal malformations in this fetus supports the diagnosis of hemifacial microsomia and sirenomelia.
- These conditions are proposed to represent parts of a continuous spectrum of mesodermal malformations.
Implications:
- This case suggests that hemifacial microsomia and sirenomelia may share a common developmental pathway within a broader mesodermal dysplasia spectrum.
- Understanding the interplay of genetic and environmental factors is crucial for future studies aiming to delineate this spectrum and improve prenatal diagnosis and counseling.
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