[Placental mesenchymal dysplasia]

Area of Science:

• Perinatology
• Pathology
• Medical Genetics

Background:

• Placental mesenchymal dysplasia (PMD) is a rare placental disorder.
• This study focuses on PMD cases not associated with Beckwith-Wiedemann syndrome.

Purpose of the Study:

• To conduct a clinical and morphological analysis of 6 cases of isolated PMD.
• To identify typical ultrasound and histopathological features of PMD.
• To evaluate pregnancy outcomes and management considerations in PMD.

Main Methods:

• Analysis of clinical data, macroscopic and microscopic placental examination.
• Histochemical (MSB staining) and immunohistochemical studies (p57, CD34, smooth muscle actin, desmin, Ki-67).
• Correlation of ultrasound findings with morphological patterns.

Main Results:

• Typical PMD signs included vascular anomalies, enlarged/edematous stem villi, and absent trophoblast proliferation.
• Ultrasound findings correlated with morphological patterns, suggesting typical diagnostic signs.
• Pregnancy outcomes varied; PMD with preeclampsia showed specific morphological changes.
• Significant variability in p57 expression was observed; desmin and smooth muscle actin showed no substantial changes.

Conclusions:

• PMD exhibits characteristic morphological and ultrasound features.
• Variability in p57, hCG, and AFP levels limits their use in PMD differential diagnosis.
• High risks of thrombosis, intrauterine growth restriction, hypoxia, and neonatal adaptation issues necessitate careful management planning.