Naegleria and House

I saw this 2-part episode of House wherein one of House's colleagues had meningoencephalitis. They worked him up for virus, bacteria and even fungi to no avail. House then had to go the site where his colleague got the infection and saw a water tank and immediately thought of Naegleria. Naegleria is a free-living amoeba which invades the olfactory epithelium after aspiration of trophozoites in water or cysts in dust and causes meningoencephalitis. After an incubation period of 2-15 days, patients develop severe headache, fever, nausea, vomiting and meningismus. Photophobia and ocular palsies are common. Rapid progression to seizures and coma follows, and most patients die within 1 week. Infection typically occurs in otherwise healthy children and young adults with a history of recently swimming in a lake or a pool. CSF findings mimic those of acute bacterial meningitis that's why they had a hard time diagnosing him. The diagnosis should be considered in patients with purulent meningitis and negative Gram's stain and culture. Diagnosis is made by visualizing motile trophozoites on wet preparation of the CSF. The only four known survivors were treated with high-dose amphotericin B (an anti-fungal) and rifampin (an anti-TB).