FGFR1 related Encephalocraniocutaneous lipomatosis in a neonate with congenital hydrocephalus

Background Encephalocraniocutaneous lipomatosis (ECCL), a type of mosaic RASopathy, is a rare neurocutaneous syndrome characterized by the involvement of tissues with ectodermal and mesodermal origins, including cutaneous, ocular, and neurological abnormalities. This report presents a case of a neonate with ECCL showing rapid progression of hydrocephalus prenatally. Case presentation A full-term female newborn presented with head circumference enlargement and a bilateral abnormal hair pattern with alopecia at birth. Brain imaging studies showed an enlarged lateral ventricle and fatty mass in the foramen magnum, suggestive of lipomas. Ventriculoperitoneal shunting and a biopsy of the skin lesion on the head were performed on day 18. These clinical, brain imaging, and cutaneous pathological findings led to the definitive diagnosis of ECCL. Furthermore, targeted resequencing revealed an activating mosaic variant of FGFR1 in tissue samples of scalp lesions. The patient is now 2 years old with good health and normal development so far, without lipoma expansion or abnormal neurological signs and symptoms. Conclusion Genetic analysis of lesions is important in cases of congenital hydrocephalus with intraspinal lipoma or nevus psiloliparus. In the present case, ventriculoperitoneal shunting early in life resulted in a good neurological prognosis without lipoma expansion.