Cerebellar Hypermetabolism in a Hodgkin Lymphoma Leads to Diagnosis of Paucisymptomatic Cryptococcus neoformans Meningitis

Abstract

Malignancy-associated cerebellar hypermetabolism on [ 18 F]FDG PET/CT has 2 major causes: paraneoplastic autoimmune encephalitis and neoplasias (leptomeningeal/cerebellar metastases and primary cerebellar tumors). We present the case of a 33-year-old man with a newly diagnosed Hodgkin lymphoma and mere episodical headache, unexpectedly displaying intense cerebellar hypermetabolism on his staging [ 18 F]FDG PET/CT. Both neurolymphomatosis and paraneoplastic subacute cerebellar degeneration were ruled out by clinical presentation, MR, and repeated lumbar punctures. Instead, cerebrospinal fluid analysis unveiled a Cryptococcus neoformans meningitis, highlighting the possibility of paucisymptomatic central nervous system infections as differential diagnosis in malignancy-related cerebellar hypermetabolism in addition to (para)neoplastic causes.

Cryptococcosis in oncology patients: a case series in a tertiary care cancer centre

“…The second patient presented with coexisting Cryptococcus neoformans meningitis and lymphoma during his workup for the same and the third patient was on induction chemotherapy for Hodgkin lymphoma when he developed disseminated cryptococcosis. Studies from literature also suggest similar cases in patients with Hodgkin lymphoma ( 7 , 15 , 16 ). Our patients except for the second case had drug associated immunosuppression and were on high levels of steroids which made them susceptible to infection.…”

“…During the past ten years, only three cases of cryptococcosis have been documented in our centre. Cryptococcosis in oncology patients has varying presentations like pulmonary nodules, meningitis, bloodstream infections, or subcutaneous mass ( 1 – 7 , 15 , 16 ). Cryptococcosis can also develop at varying stages of the malignancy.…”