Forensic Neuropathologic Phenotypes of Fungal Central Nervous System Infections: A Case Series

Fungal infections of the central nervous system (FI-CNS) are life-threatening infections that most commonly affect immunocompromised individuals, but immunocompetent individuals may also be infected. Although FI-CNS are relatively rare, the prevalence of FI-CNS is on the rise because of the increasing number of transplant recipients, human immunodeficiency virus-infected individuals, and use of immunosuppressive therapies. Most cases of FI-CNS originate from outside the central nervous system. The etiologic fungi can be classified into 3 fungal groups: molds, dimorphic fungi, and yeasts. The clinical presentation of FI-CNS is highly variable and may be difficult to diagnose premortem. We present a case series of 3 patients, each infected by 1 representative species from each of the 3 fungal groups (Aspergillus species, Blastomyces species, Candida species) to illustrate different neuropathologic phenotypes of FI-CNS. All 3 patients had no history of immunodeficiency and were not suspected to have FI-CNS until they were diagnosed at autopsy. Fungal infections of the central nervous system are often fatal due to delayed diagnosis and diagnostic testing. Awareness of such poly-phenotypic manifestations of FI-CNS will be helpful in reducing delayed diagnosis. It is important for clinicians to include FI-CNS on the differential diagnosis when radiographic findings are nonspecific.