Pontocerebellar hypoplasia type 7 with multiple congenital anomalies and progressive neurological course: a case report

Introduction Pontocerebellar hypoplasia type 7 (PCH7) is an ultrarare autosomal recessive neurodevelopmental disorder caused by biallelic loss-of-function variants in TOE1 . Typical manifestations include pontocerebellar hypoplasia and 46,XY disorders of sex development. However, because of its rarity, the longitudinal clinical course and full phenotypic spectrum of PCH7 remain incompletely defined. Case presentation We describe an infant presenting with feeding difficulties due to bulbar palsy at 3 months of age. Brain magnetic resonance imaging revealed pontocerebellar hypoplasia with bilateral ventriculomegaly and supratentorial atrophy. The patient also exhibited a disorder of sex development with a 46,XY karyotype and female external genitalia, and genetic testing confirmed the diagnosis of PCH7. Her clinical course was marked by persistent hypertension, sustained thrombocytosis, and progressive thoracic deformity leading to chronic respiratory insufficiency. She developed infantile epileptic spasms syndrome (IESS) at 8 months of age and died of respiratory failure at 18 months of age. Conclusion This case further delineates the phenotypic spectrum of PCH7 by highlighting a severe progressive course with both neurological and systemic dysfunction. In addition to the established core features of PCH7, this patient exhibited IESS, persistent thrombocytosis, and rapidly progressive thoracic deformity, which may represent uncommon or underrecognized features of the disorder. Recognition of these manifestations may contribute to improved diagnostic accuracy, prognostic counseling, and multidisciplinary management.