Title : CNS coccidiomycosis in an individual with multiple sclerosis on fingolimod – A case report
Abstract:
Introduction: Fingolimod is an FDA-approved oral disease-modifying therapy for relapsing-remitting forms of multiple sclerosis and works through inhibition of lymphocyte egress from secondary lymphoid organs, reducing circulating levels of lymphocytes. While Fingolimod, and the other monoclonal antibodies or immune system modulators used in the treatment of multiple sclerosis (MS), have been associated with fungal infections of the central nervous system (CNS), no case of Coccidiomycosis infection of the CNS has thus far been described.
Case Report: A 56-year-old female with MS on fingolimod from the Southwestern United States presented to her Infectious Disease (ID) physician for routine follow-up following a hospitalization for disseminated Coccidiomycosis. The patient had a lumbar puncture performed at this time, which showed elevated white blood cells and a positive Coccidioides CSF complement fixation titer of 1:1 undiluted, evidence of a CNS Coccidioides infection. MR taken one month after this appointment showed several new signal abnormalities not present on the patient’s comparison MR taken 3 years prior; these identified lesions showed either resolution or significant improvement one month later on a follow-up MR.
Discussion: While fungal infections are known to occur in the setting of treatment for MS, no cases prior have described Coccidioides infection of the CNS. A unique aspect of the case presented is how the patient’s history of multiple sclerosis both contributed to the development of her CNS infection and further complicated the process of diagnosis as evident in the patient’s MRI. While the lesions present in fungal CNS infections are normally leptomeningeal in nature, they can potentially imitate the demyelinating lesions as seen in MS, making diagnosis difficult. Due to the diagnostic difficulty demonstrated in the case above, clinicians should have a high degree of suspicion for Coccidioides in endemic regions when working with patients being actively treated for MS.
Audience Take Away Notes:
- Clinicians should maintain a high level of suspicion for fungal diseases in the setting of patients with multiple sclerosis who are on immunosuppressive medications.
- Patients with multiple sclerosis being treated with immunosuppressive medications are likely at a higher risk for disseminated fungal infections.
- While MRI is a highly sensitive diagnostic tool, some challenges may occur in differentiating lesions caused by multiple sclerosis verses Coccidioides infection.
- Immunosuppressed patients may have atypical presentations of fungal infections, as our patient never was diagnosed with pulmonary Coccidiomycosis prior to her CNS infection.
