Microbial Diseases of the Nervous System – Key Vocabulary

Vocabulary flashcards summarizing major pathogens, conditions, and concepts from the lecture on microbial diseases of the nervous system.

Central Nervous System (CNS)

The brain and spinal cord, responsible for integrating sensory information and responding accordingly.

Peripheral Nervous System (PNS)

All nerves that branch from the CNS, connecting it to limbs and organs.

Meninges

Protective membranes (dura, arachnoid, pia mater) surrounding the brain and spinal cord.

Cerebrospinal Fluid (CSF)

Fluid in the subarachnoid space that cushions the CNS and can harbor pathogens in meningitis.

Blood-Brain Barrier

Selective barrier that restricts passage of substances from the bloodstream into brain tissue.

Meningitis

Inflammation of the meninges, often presenting with fever, headache, and stiff neck.

Encephalitis

Inflammation of the brain itself, leading to neurologic dysfunction.

Meningoencephalitis

Simultaneous inflammation of both brain and meninges.

Bacterial Meningitis

Severe meningitis caused by bacteria; progresses rapidly and can be fatal due to endotoxin-induced shock.

Viral Meningitis

Generally milder form of meningitis caused by viruses.

Haemophilus influenzae type b (Hib)

Gram-negative bacterium whose encapsulated type b strain causes meningitis mainly in young children; preventable by Hib vaccine.

Neisseria meningitidis

Encapsulated, aerobic, gram-negative diplococcus causing meningococcal meningitis; common in dormitory and military settings.

Serogroup Vaccine

Vaccine targeting specific capsular antigens of N. meningitidis to prevent meningococcal disease.

Spinal Tap (Lumbar Puncture)

Procedure to obtain CSF for diagnosis of meningitis; pathogens must be processed promptly.

Listeria monocytogenes

Gram-positive rod causing listeriosis; reproduces inside phagocytes and spreads cell-to-cell.

Listeriosis

Food-borne infection that can lead to meningitis, sepsis, and fetal loss in pregnant women.

Actin-Based Motility

Mechanism by which L. monocytogenes propels itself through host cells using polymerized actin tails.

Clostridium botulinum

Gram-positive, endospore-forming anaerobe producing botulinum neurotoxin.

Botulism

Flaccid paralysis resulting from ingestion or in-body production of botulinum exotoxin; can be food-, wound-, or infant-associated.

Infant Botulism

Illness in infants from C. botulinum growth in intestines, often linked to honey consumption.

Clostridium tetani

Gram-positive, endospore-forming anaerobe that causes tetanus via tetanospasmin toxin.

Tetanospasmin

Potent neurotoxin released by C. tetani that blocks inhibitory neurotransmitters, inducing muscle spasms.

Tetanus Toxoid (DTaP)

Inactivated tetanus toxin used in vaccines to elicit protective antibodies; boosters needed every 10 years.

Mycobacterium leprae

Acid-fast bacterium causing leprosy; grows best at 30 °C in skin and peripheral nerves.

Leprosy (Hansen’s Disease)

Chronic infection leading to skin lesions and nerve damage; treated with multidrug therapy.

Tuberculoid Leprosy

Localized form with loss of skin sensation due to nerve involvement.

Lepromatous Leprosy

Disseminated form with disfiguring nodules and mucous membrane involvement.

African Trypanosomiasis

Sleeping sickness caused by Trypanosoma brucei gambiense transmitted by tsetse flies, leading to CNS deterioration.

Antigenic Variation

Strategy by which T. brucei frequently changes its surface glycoproteins to evade host antibodies.

Naegleria fowleri

Free-living amoeba that causes primary amebic meningoencephalitis; infection is usually fatal.

Rabies Virus

Bullet-shaped Lyssavirus causing fatal encephalitis; forms Negri bodies in brain tissue.

Negri Bodies

Cytoplasmic inclusions in neurons indicative of rabies infection.

Prion

Misfolded protein (PrPSc) that induces misfolding of normal PrPc, leading to transmissible spongiform encephalopathies.

Transmissible Spongiform Encephalopathies (TSE)

Group of fatal neurodegenerative diseases caused by prions, e.g., sheep scrapie.