Fatal encephalopathy due to Lagochilascaris minor infection.

A 14-year-old boy with a tetralogy of Fallot showed a subacute, progressive encephalopathy characterized by headache, stupor and coma. Death occurred three months after the beginning of the illness. Neuropathologic examination revealed diffuse foci of necrosis of the cerebral hemispheres and cerebellum, and the presence of the nematode Lagochilascaris minor in the parenchyma and in the cisterns at the base of the brain. In almost all 28 cases of human lagochilascaris previously reported, the worms were located in the soft tissues of the neck and throat, tonsils, mastoids and paranasal sinuses. This is the first reported case in which Lagochilascaris infected the brain. Since the life cycle of the worm is unknown the pathogenesis of the central nervous system lesions is obscure.