Neuropathologic Findings in Mowat-Wilson Syndrome at Autopsy, Including a Suprasellar Spindle Cell Lipoma.

Mowat-Wilson Syndrome is an autosomal dominant disorder caused by de novo heterozygous mutations of ZEB2 on 2q22. It is characterized by developmental delay, Hirschsprung's disease, seizures, and a wide variety of malformations affecting the neurologic, cardiac, and genitourinary systems. Reports describing the findings of Mowat-Wilson Syndrome at autopsy are sparse. Case reports of suprasellar spindle cell lipomas are even rarer, a circumstance that contributes to uncertainty regarding their etiology as true neoplasms rather than congenital malformations. Here we report the gross, histopathologic, and molecular findings of a 4-year-old female with Mowat-Wilson Syndrome presenting with sepsis in the setting of otitis media and incidentally found to have a rare suprasellar spindle cell lipoma demonstrating loss of RB1 by immunohistochemistry, suggestive of a neoplastic etiology.