Parasitic Eosinophilic Meningoencephalitis: Part 1

Eosinophilic meningitis is defined by the presence of higher than 10 eosinophils per ml or at least 10% eosinophils in the total cerebrospinal fluid (CSF) leukocyte count. 

Severe headache, stiff neck, nausea, vomiting, and fever are some of the symptoms of eosinophilic meningitis. Additionally, patients may report tingling, numbness, weakness, and vision problems in their limbs. Some people may also experience muscle soreness or skin rashes. 

There are two types of eosinophilic meningitis: infectious and non-infectious. The infectious causes are further divided into nonparasitic and parasitic categories. It is crucial to remember that very early in the course, CSF may not always be eosinophil-rich. Hence, a repeat lumbar puncture a few days into the illness may be required to detect eosinophilia if there is a suspicion of the parasite-related causes of meningitis.

Despite multiple etiology, the most common cause of eosinophilic meningitis is parasite infection, while there are other potential causes as well like neoplastic diseases, drug use, prosthesis reactions, and miscellaneous idiopathic conditions. 

Taenia solium, Gnathostoma spinigerum, and Angiostrongylus cantonensis are amongst the most common parasites. Although these parasites are endemic in tropical nations, they are currently spreading throughout the world as a result of frequent travel and the availability of exotic foods everywhere.

To conclude, we can say that the response to infectious agents is most commonly linked to CSF eosinophilia. It can be ectopic migration or neurotropic parasites or another pathogen. The primary focus should be on food safety because issues like climate change and migratory populations are not reversible.

 References

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