Amoebic Meningoencephalitis

Amoebic meningoencephalitis is a severe and often fatal brain infection caused by free-living amoebae, primarily Naegleria fowleri, but also Acanthamoeba species and Balamuthia mandrillaris. These amoebae typically live in warm freshwater environments, such as lakes, rivers, and hot springs, but can also be found in soil and inadequately treated swimming pools.

Types of Amoebic Meningoencephalitis:
Primary Amoebic Meningoencephalitis (PAM):

Caused by: Naegleria fowleri.
Transmission: Typically occurs when contaminated water enters the nasal passages, usually during activities like swimming or diving. The amoeba then travels to the brain via the olfactory nerve.
Symptoms: Early symptoms resemble those of bacterial meningitis and include headache, fever, nausea, vomiting, and a stiff neck. As the disease progresses, symptoms can include confusion, seizures, hallucinations, and coma.
Prognosis: PAM is rapidly progressing and often fatal, with a very high mortality rate.
Granulomatous Amoebic Encephalitis (GAE):

Caused by: Acanthamoeba species and Balamuthia mandrillaris.
Transmission: Infection can occur through skin wounds or inhalation of cysts, with the amoebae eventually spreading to the brain.

Symptoms: GAE progresses more slowly than PAM. Symptoms can include headaches, fever, stiff neck, sensitivity to light, neurological deficits, and changes in behavior or personality.
Prognosis: GAE is also often fatal, but some patients may survive with early diagnosis and treatment.
Diagnosis and Treatment:

Diagnosis: Early diagnosis is challenging due to the non-specific symptoms. It typically involves a combination of clinical history, imaging studies (such as MRI or CT scans), cerebrospinal fluid analysis, and detection of amoebae in brain tissue or fluid samples.

Treatment: Treatment options are limited and not always effective. They can include antifungal and antiparasitic medications, such as amphotericin B, miltefosine, and others, often in combination. Early and aggressive treatment offers the best chance of survival.