Primary Amoebic Meningoencephalitis

Primary amoebic meningoencephalitis is an infection by free-living amoebae, which sometimes act as parasites in humans, deliberate infection through the nostrils. It amebiasis they call the "main" to distinguish them from amoebiasis by Entamoeba histolytica, which also occasionally attacks the central nervous system in this case is called amoebic meningoencephalitis secondary. Symptoms include fever, headache, rhinitis, respiratory symptoms, impaired sense of smell, hearing, and mental confusion, loss of consciousness and motor function. Diagnosis: lumbar puncture to remove cerebrospinal fluid, which is purulent, with an increase in polymorphonuclear increased albumin and absence of bacteria, rather it is an amoeba, which is the only way to etiology.

Etiologic agent
They have recognized three genera that cause primary amoebic miningoencefalitis: Naegleria fowleri, Acanthamoeba and Hartmannella. These free-living amoeba trophozoites as sweet and warm water (25 ° to 35 °), and lakes, ponds, rivers, etc., where they multiply by binary fission and feed on bacteria. Infection in humans is obtained mainly by contaminated water that reaches the nostrils, especially by bathers or swimmers rinse or clean your nostrils with water in which they bathe. They penetrate the cribriform plate, invade and colonize the brain in a different location.

The initial invasion, through the nose, resulting in a temporary inflammation of the nasal passages, the secretions, which often goes unnoticed. The main lesions found in the brain and meninges, but the olfactory tract, medulla and cerebellum are also affected. The brain seems tender, swollen and hemorrhagic necrosis, which hyperemic meninges with hemorrhagic focus and covered by a purulent exudate composed of mononuclear and polimorfononucleares. There necrotizing vasculitis and thrombosis in some areas.

Prognosis
Grave. Usually fatal in 80% of cases of Naegleria fowleri infection by amoeba.

Treatment
Because antibiotics do not work, amphotericin B is used, which has been shown to have great power antiambiano in vitro in several strains of Naegleria and has been protecting animals. It can be used intravenously or intraventricularly while doses of 0.25 to 1 mg / kg / day. If treatment is delayed, it is likely that the patients progressed to death.