Association of HAX1 deficiency with neurological disorder.

Severe congenital neutropenia (SCN) is a rare, heterogeneous, primary immunodeficiency disorder characterized by early onset of severe bacterial infections. We here describe a case of SCN associating neutropenia and neurodevelopmental delay. The girl was well until the age of 9 months, when she suffered from an episode of convulsion. Subsequently, she developed several episodes of superficial abscesses, oral ulcers and otitis media. Further work-up revealed severe congenital neutropenia caused by a homozygous mutation (R86X) in the antiapoptotic molecule HAX1. She also suffered from psychomotor retardation and recurrent seizures. This case illustrates that HAX1 deficiency may be associated with a neurological phenotype.