Primary Central Nervous System HIV Infection Definition Neurologic complications directly attributable to primary infection of the CNS by human immunodeficiency virus-1 (HIV-1) Clinical Features Epidemiology Virus enters CNS early, may remain subclinical Neurologic complications develop in up to 50% of…
General Viral Effects on the Central Nervous System Definition CNS viral infection associated with clinical or laboratory evidence of neurologic dysfunction based on viral tropism Clinical Features Epidemiology Viruses: number one cause of encephalitis and meningitis Most cases: acute, self-limited…
Cerebral Toxoplasmosis Definition CNS infection with Toxoplasma gondii , a ubiquitous obligate intracellular protozoan that parasitizes humans and animals Clinical Features Epidemiology Worldwide distribution with increased incidence in France, Central and South America Definitive hosts: cats 225,000 cases/year in United…
Cerebral Cryptococcosis Definition Severe CNS fungal infections caused by the genus Cryptococcus ; includes meningitis and focal “cryptococcomas” Clinical Features Epidemiology C. neoformans : ubiquitous in soil, bird excrement, compost C. gattii : tropical/subtropical climates, North American western coast Eucalyptus…
Acute Purulent Meningitis Definition An acute inflammatory process involving leptomeninges and cerebrospinal fluid Clinical Features Epidemiology Approximately 2.5/100,000 (United States) each year Hematogenous spread most common Pneumonia with bacteremia Other routes Direct inoculation (trauma, procedures) Invasion (sinusitis, mastoiditis, oral infections)…
Chordoma of Skull Base Definition Slow-growing, locally aggressive bone tumor; believed to originate from embryonic notochord rests (“ecchordosis physaliphora”), found incidentally in 1% to 2% of autopsies Clinical Features Epidemiology Rare tumor: 0.2% of all intracranial tumors; 3% to 4%…
Definition Hematogenous spread of a primary tumor originating outside the CNS to the brain or its coverings Clinical Features Epidemiology Most common brain tumors in adults Incidence of about 10 to 30 per 100,000 per year CNS metastases found in…
Definition Benign developmental thin-walled cysts defined by type of epithelium and location Examples: epidermoid, dermoid, colloid, arachnoid, endodermal, and ependymal Clinical Features Epidemiology Constitute about 1% of intracranial masses Affect all ages No gender predominance Believed to result from developmental…
Definition Primary tumors of the brain and spinal cord arising from arachnoidal/pial melanocytic cells Melanocytoma: localized, low-grade, noninvasive Melanoma: malignant, invasive, mitotically active Clinical Features Epidemiology Very rare entities Wide age range, but most occur in the fifth decade You’re…
Pituitary Adenomas Definition A neoplasm of the adenohypophysis Most common tumor of the pituitary gland Clinical Features Epidemiology 10% to 15% of all intracranial tumors Annual incidence: 0.2 to 2.8 cases per 100,000 About 20% to 30% of pituitary adenomas…