Microbiology
Summary
Naegleria fowleri is an amoeba present in freshwater lakes and is associated with water sports. Rarely, over-the-counter nasal irrigation systems and contact lens solutions can be potential sources of infection. N. fowleri enters the CNS via the cribriform plate, and presents with symptoms of meningitis and encephalitis (if N. fowleri is the perpetrator, the disease is termed as primary amebic meningoencephalitis, a rapidly fatal disease with a poor prognosis.)
Diagnosis of this parasite is made after examining cerebrospinal fluid from a spinal tap under a microscope. If detected early, the infection can be treated with a drug called amphotericin B. Adhering to cleanliness and being aware of potential danger zones can mitigate the risk of this disease.
Lesson Outline
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FAQs
N. fowleri is a free-living amoeba that is found mainly in freshwater bodies such as lakes and studied in parasitology due to its capacity to cause fatal brain infection known as primary amebic meningoencephalitis (PAM). It usually enters the body through the nose and travels to the brain via the cribriform plate.
N. fowleri thrives in warm temps, particularly in freshwater like lakes and hot springs. Once it enters the nose, it travels to the brain where it can cause a serious infection. It is important to note that this amoeba cannot survive in salt water, swimming pools properly treated with chlorine, or water that is too cold.
Diagnosing a N. fowleri infection can be quite tricky due to its rapid progression and overlap of symptoms with other neurological conditions. A lumbar puncture is often performed to take a sample of cerebrospinal fluid for analysis. The presence of N. fowleri can be confirmed with specific stains and microscopic examination. Further confirmation can be done by detecting its DNA or antibodies against the parasite in the patientÕs cerebrospinal fluid or tissue.
The most common treatment for N. fowleri infection is with amphotericin B, often used in combination with other drugs. Amphotericin B is an antifungal medication that has shown to have some effect against the amoeba both in vitro and in patients. However, the disease has a high fatality rate because it progresses rapidly and is often diagnosed late. Rapid diagnosis and initiation of treatment are critical for improving the chances of survival.
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