Central nervous system fungal infections in tropics.

Fungal infections of the central nervous system range from chronic indolent forms to acute fulminant forms causing significant morbidity and mortality. They often show atypical and variable neuroradiologic findings because of the absence of typical inflammatory response. The neuroradiologist must have high degree of suspicion in immunocompromised patients regarding the possibility of central nervous system fungal infections and keep in mind the appearances of various fungi even when immune response is intact. Next is to identify the pattern of involvement whether hematogenous or direct sinonasal and then make a well-informed speculation regarding the type of the pathogen based on the clinical features and imaging appearance.