[One episode of meningoencephalitis, three diagnoses].

Meningo-encephalitis is a set of threatening diseases. The treatment needs to be started quickly for pathogens such as herpes simplex virus type 1 or Listeria monocytogenes. Apart from these classical etiologies, many other diseases may induce meningo-encephalitis. We report the case of a patient, infected with HIV, who presented a history of meningo-encephalitis due to herpes simplex type 1. Three weeks later, he presented an encephalopathy due to aciclovir and then we discovered a chronic meningitis in relation with his HIV infection.