[Neuromeningeal hypodermyiasis complicated by hydrocephaly. Value of nuclear magnetic resonance imaging].

A 9-year old country boy developed blepharitis with inflammation of the face and, 1 month later, eosinophilic meningitis with paralysis of 3 limbs and of an abducent nerve. Nuclear magnetic resonance imaging of the central nervous system disclosed a lesional signal beneath the floor of the 4th ventricle, which was compatible with the presence of a larva of fly. Treatment with thiabendazole was tried, and the clinical signs regressed. Six months later, an asymmetrical hydrocephalus due to obstruction of Monroe's foramen by an inflammatory granuloma was discovered. Human hypodermyasis, due to migration in tissues of larvae of flies, is not rare in cattle-breeding areas. Neuromeningeal disorders are observed in 12% of the cases, consisting of eosinophilic meningitis sometimes associated with neurological deficit or seizures. Such complications as intracerebral haematoma or meningeal haemorrhage may occur during the usually benign course of the disease.