Cryptococcosis in the Central Nervous System in a 36-Year-Old Japanese Man: An Autopsy Study

Abstract

Cryptococcus neoformans is present in our surroundings, and is particularly common in bird feces, such as pigeon droppings. Autopsy cases of cryptoccocal meningoencephalitis in young individuals are very rare. The aim of this study is to describe the autopsy findings of cryptococcal meningoencephalitis of the brain and spinal cord in a young man who presented no apparent immunosuppression. A 36-year-old Japanese man presented with hemoptysis and admitted to our hospital. Chest X-ray revealed a small cavity in the left lung. He soon developed somnolence, neck stiffness, positive abnormal neurological reactions, and increased muscular tonus. Cryptococcus neoformans was detected in the cerebrospinal fluid. Despite appropriate chemotherapy (amphotericin B), he died 18 days after the admission. Autopsy revealed clouding of the leptomeninges of the brain and spinal cord. The brain (1,830 g, normal 1,300 − 1,500 g) showed marked edema and bilateral tonsillar herniation. The lung revealed a cavity in the left lower lobe. Microscopically, the leptomeninges were diffusely infiltrated with numerous cryptococcus fungi and mononuclear cells. Cryptococcus fungi were also present in the parenchyma of the brain and spinal cord, in which mild gliosis and vascular proliferation were recognized. The lung cavity revealed a presence of Cryptococcus neoformans and gram-positive bacteria with granulomatous tissue reactions. The cryptococcal granulomas were also recognized in the liver and spleen. The cause of death was thought to be tonsillar herniation. The present study indicates that severe cryptococcosis involving leptomeninges and parenchyma of the brain and spinal cord may occur in an otherwise healthy individual.