Teaching NeuroImage: Cryptococcal brain pseudocysts in an immunocompetent patient
James Scozzafava, MD,
Haley Block, MD,
Negar Asdaghi, MD, MSc and
Zaeem A. Siddiqi, MD, PhD
From the Division of Neurology, Department of Medicine (H.B., N.A., Z.A.S.), University of Alberta, Edmonton, Canada; and the Division of Critical Care Medicine (J.S.), University of Calgary, Calgary, Canada.
Address correspondence and reprint requests to Dr. James Scozzafava, Division of Critical Care Medicine, Foothills Medical Centre, 1403 29 St. NW, University of Calgary, Calgary, AB, Canada, T6G 2R7 jjs9{at}ualberta.ca
A 52-year-old man developed fever, meningismus, and decreasinglevel of consciousness over 2 days. On arrival he was minimallyresponsive to external stimuli and was profoundly rigid. Therewas no history of immunosuppression; however, he worked as avacuum truck operator and reported exposure to chicken and pigeonfeces in the weeks prior to his illness. CSF opening pressurewas >30 cm of H2O with a mild lymphocytic pleocytosis (239x 10*6 cells/L) with protein at the upper limit of normal (0.45mmol/L), and normal glucose (4.1 mmol/L). HIV serology was negative.ELISA and India ink stain were positive for cryptococcus. CSFcultures identified Cryptococcus neoformans var Gatti as thepathogenic species. Other infectious causes, including hepatitisB and C viruses, herpes simplex virus, mycobacterium tuberculosis,and other fungal sources, were all excluded. Brain MRI showedbilateral pseudocysts predominantly involving the basal ganglia,and post-gadolinium sequences showed little enhancement of thecysts or surrounding parenchyma (figure). The patient receivedIV amphotericin B and flucytosine for 3 weeks followed by maintenancetherapy with fluconazole. A lumbar CSF drain was inserted totreat raised intracranial pressure. Serial chest x-rays performedto monitor for pulmonary disease or complications showed noevidence of cryptococcal pulmonary infection. At the time ofdischarge, the patient had only mild residual bilateral bradykinesiaand rigidity.
(A) Axial T2 sequence showing bilateral pseudocysts as hyperintensities (arrowheads) predominantly involving the basal ganglia. The pseudocysts are thick walled and septated with a proteinaceous content depicted by their relative hyperintensity compared to CSF. (B) Post-gadolinium MRI sequences showing little to no enhancement of the cysts or surrounding parenchyma.
This case highlights the potentially dramatic imaging appearanceof cryptococcal meningoencephalitis. Post-gadolinium MRI sequencesshowed little to no enhancement of the cysts or surroundingparenchyma, a feature that differentiates this disorder fromother inflammatory or malignant processes, which are usuallyassociated with breakdown of local blood–brain barrierand uptake of gadolinium.1–3 The case further demonstratesthat early and aggressive management of severe cryptococcalmeningoencephalitis can lead to a favorable outcome.
Disclosure: The authors report no conflicts of interest.
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