Diagnostic Imaging for Fungal Infections of the Central Nervous System

A 31-year-old female heart transplant recipient was admitted to the hospital for a recent history of progressively worsening headaches. Her past medical history included doxorubicin (Adriamycin)-induced cardiomyopathy and cisplatin-induced nephropathy secondary to a nonrecurrent osteosarcoma that occurred in 1982; in 1991, she underwent orthotopic heart transplantation. After transplantation (at age 29), she was admitted on several occasions for organ rejection and for onset of moderate-to-severe headaches after an uneventful pregnancy. In September 1992, a complete neurological evaluation for the headaches was unrevealing, and she was treated symptomatically. The patient was admitted to another hospital for worsening headaches in January 1993; her WBC count was 0, and a lumbar puncture indicated a pressure of 450 mm H20. She was diagnosed with pseudotumor cerebri and given acetazolamide (Diamox). While hospitalized, she developed a low-grade fever, and empiric antibiotic therapy was begun with defervescence. She was subsequently transferred to the intensive care unit for acute worsening of liver and renal function with hepatic encephalopathy. Cyclosporine and azathioprine were discontinued, and prednisone was converted to solumedrol. Her neurological condition worsened with coma and seizures. Computed tomography (CT) scans of the brain were normal. Because of hepatic failure, she was transferred to another hospital for a possible liver transplant. A new CT scan of the brain (3 days after the previous scan) showed multiple, circumferential, low-density lesions. The lesions were considered representative of a possible infectious process, perhaps Nocardia, tuberculosis, septic emboli, toxoplasmosis, or fungus. Shortly thereafter, the patient's pupils became