Postencephalitic porencephaly, hydranencephaly or polymicrogyria. A review

Area of Science:

• Neuropathology
• Developmental Neuroscience
• Pediatric Pathology

Background:

• Fetal encephalitis is a significant cause of congenital brain abnormalities.
• Porencephaly, hydranencephaly, and polymicrogyria are severe structural brain malformations.
• The interplay between infectious agents and brain development is complex and not fully understood.

Purpose of the Study:

• To review necropsy cases of fetal encephalitis associated with porencephaly, hydranencephaly, or polymicrogyria.
• To investigate the pathogenetic relationship between encephalitis and hemispheric malformations.
• To explore whether encephalitis is primary or secondary to pre-existing brain lesions.

Main Methods:

• Review of twenty necropsy cases, including five from the authors' material.
• Detailed pathological examination of brain specimens.
• Analysis of lesion characteristics and developmental stages.

Main Results:

• Supratentorial lesions were frequently associated with cerebellar cortical dysplasias.
• Cases demonstrated both encephalitis secondary to pre-existent lesions and lesions secondary to encephalitis.
• Examples included basket brain, recent porencephalic necrosis, and formative polymicrogyria.

Conclusions:

• Fetal encephalitis and severe hemispheric malformations share a complex pathogenetic interdependence.
• Encephalitis can be either the cause or consequence of structural brain defects.
• Understanding these mechanisms is crucial for diagnosing and managing congenital neurological disorders.