MyPACS.net: Radiology Teaching Files > Case 3953376

never visited 19 YO MALE WITH NEW ONSET SEIZURE
Contributed by: Faculty and residents Children's Hospital.
Patient: 19 year old male
History:

19 yo male presents with new onset seizure. history of recent immigration to u.s.a. from guatemala, according to clinician. mri of brain ordered after non-contrast ct from referring hospital demonstrated right frontal lobe focus of low attenuation with several-mm-thick halo of edema.

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Findings: right frontal lobe with cystic lesion that is generally rounded and relatively sharply-marginated with a halo of edema. following contrast administration the lesion demonstrated avid enhancement in a ring-like pattern. no other lesions were found in a complete survey of brain and spinal cord. findings on diffusion weighted imaging were consistent with "t2 shine-through."
Diagnosis: presumably this is a case of cysticercosis.
Discussion:

most common parasitic cns infestation. will involve cns in approximately 90% of affected patients. termed neurocysticercosis, this is a chronic disease with varied presentation.
most common cause of symptomatic epilepsy worldwide.

causative agent is taenia solium (pork tapeworm)larvae, which gains access to host via gi tract following ingestion of infected food or ingestion of infected fecal material (such as contaminated fertilizer on fruit or vegetables).


ncc occurs in four variations: meningeal; parenchymal; ventricular; and mixed. complications of infestation include stroke, hydrocephalus, seizure, meningitis, arachnoiditis, cerebritis, ependymitis, chorioretinitis. pts may present with progressive dementia, behavioral disturbances, or pseudohypertrophy of the calf muscles. living cysticerci dampen host immune responses until their deaths, usually occurring approximately 2-6yrs after infestation. acute inflammation with mononuclear cell infiltration, fibrosis, and eventual collapse of the cyst with calcification occur in stages.

most accurate serologic test is currently enzyme-linked immunotransfer blotting, which demonstrates about 90 to 100% sensitivity for multiple intracranial cysticerci. however, results are thought to be negative in up to 80% of ncc cases with only one lesion.

imaging findings are not pathognomonic. the most specific finding on cross-sectional imaging is an eccentric scolex within the cyst. differential diagnosis of ring-enhancing lesions on computed tomography includes brain abscesses, cns tuberculosis, tumefactive multiple sclerosis, radiation necrosis (9months to 3yrs after xrt), aneurysm with intraluminal thrombus, post-operative gliosis, infarct and necrotic brain tumors such as mets or glioblastomas.

References:

Cysticercosis, CNS

Last Updated: August 26, 2005
Author: Anil Khosla, MD, Assistant Professor, Department of Radiology, Mallinckrodt Institute of Radiology, Washington University School of Medicine

Anil Khosla, MD, is a member of the following medical societies: American College of Radiology, American Roentgen Ray Society, American Society of Neuroradiology, North American Spine Society, and Radiological Society of North America

Editor(s): Jeffrey L Creasy, MD, Associate Professor, Associate Section Head, Division of Neuroradiology, Director, Neuroradiology Fellowship, Department of Radiology, Vanderbilt University; Bernard D Coombs, MBChB, PhD, Consulting Staff, Department of Specialist Rehabilitation Services, Hutt Valley District Health Board, New Zealand; Georges M Salamon, MD, Visiting Research Professor, Department of Radiology, David Geffen School of Medicine, University of California at Los Angeles; Robert M Krasny, MD, Visiting Assistant Professor of Radiology, University of California at Los Angeles Medical Center; Consulting Staff, Healthcare Management Partners; and James G Smirniotopoulos, MD, Professor and Chair, Professor of Radiology, Neurology, and Biomedical Informatics, Department of Radiology and Radiological Sciences, Uniformed Services University of the Health Sciences
Comments:
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Additional Details:

Case Number: 3953376Last Updated: 03-15-2006
Anatomy: Cranium and Contents   Pathology: Infection
Modality: MRExam Date: 02-18-2006Access Level: Readable by all users
Keywords: helminth, cysticercosis, larry nerdville

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