Describe the imaging findings of central nervous system cryptococcosis;discuss the different findings in immunocompetent and immunocompromised patients and briefly review the literature on the subject.
Cryptococcus neoformans ,a saprophytic fungus isolated from soil contaminated with bird excreta,
is particularly pathogenic in immunocompromised patientsand is the third most common pathogen in central nervous system (CNS) infections,
in patients with acquired immunodeficiency syndrome (AIDS),
after infection with human immunodeficiency virus (HIV) and Toxoplasma gondii .
The major environmental sources of C.
neoformans include soil contaminated with pigeon excreta and eucalyptus...
Findings and procedure details
CNS cryptococcosis produces a wide variety of MRI features that may vary depending on the immunological status of the patient.
The MRI findings range from single to multiple alterations such as hydrocephalus,
dilated perivascular spaces,
plexitis (via hematogenous dissemination),
and pseudotumor (cryptococcoma),
occurring in isolation or concomitantly with other MRI findings. Chronic granulomatous reactions caused by C.
Dilatedperivascular spaces and basal ganglia pseudocysts are the most frequently described feature on MRI.
These findings are more common in immunocompromised patients.
Signal characteristics can vary dependant on the form of infection.Meningeal diseasecan showleptomeningeal enhancement.
Cryptococcomas have low signal on T1,
high signal on T2/FLAIR andvariable enhancement,
ranging from no enhancement to peripheral nodular enhancement.Gelatinous pseudocysts tend to give a "soap bubble"...
The spectrum of MRI findings in CNS cryptococcosis in AIDS.
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AIDS-related CNS cryptococcosis: radiologic-pathologic correlation.
AJNR Am J Neuroradiol.
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