Microbiology - diseases nervous system Flashcards
bacterial meningitis 5 common causes
Neisseria meningitis, Strep pnumoniae, haemophilus influenzea, listeria monocytogenes, Streptococcus algactiae
Neisseria meningitidis
diplococcus, gram negative, meningococci, polysaccharide capsule, fimbriae, LOS / endotoxin, lives inside phagocyte
Streptococcus pneumoniae
Gram positive, IgA protease and enzymes interfere with phagocytosis, phosphorylcholine targets endocytosis, intracellular
listeria monocytogenes
gram positive coccobacillus,rarely pathogenic, synthesizes lysterosin O to break open phagosome, grows in cytosol, recruits tail to shoot into other cells. Problem for pregnant women and immunocomp.
rabies
-ssRNA lyssavirus, endocytosed by muscle cells. Exteremely deadly. seizures paralysis. Test for antibodies in blood or negri bodies post mortem. Treat with antibodies and vaccine. Helical capsid, glycoproteins on envelope.
listeria transmission
food
s. algiticae transmission
birth
neisseria spread by
close contact
tuberculoid leprosy
non progressive, T cells can control
leprotomous leprosy
weak tcell response, destroys tissues digits facial features
leprosy causitive agent
mycobacterium lepraea, high gc gram positive mycolic acid, acid fast stain likes cooler places,, transmitted person to person contact breaks in skin.
pityriasis versicolor
superficial skin mycoses, interferes with melanin production
leishmania
produced by bite of sand flies. protozoan leshmania parasite. Treat with amphotericin B, flucanazole. Skin sores erupt weeks to months after birte
viral meningtis caused by
enterovirus (90%)small +ssRNA non enveloped like coxsackie enter through stomach. Diagnose by meningitis but no bacteria or fungus in CSF. get through contaminated food. cytolytic.
polio caused by
poliovirus is enterovirus. drinking wager or eating. Virus destroys motor neurons. Observe virus in throat or feces.
mycoses of nervous system
spread from lungs to CNS. Cryptococcus neoformans. From pigeon droppings. Spherical single celled fungus with polysaccharide capsule.
sleeping sickness caused by
trypanosome bruceii. changes surface glycoproteins. Very sleepy, and deadly. Tetse fly. Find trypanosomes in blood lymph or CSF.
botulism
clostridium botulism, toxin produced by vegetative cells. most powerful toxin. Paralysis. Treat with botulism antitoxin. Culture or toxin detection.
botulism toxin
prevents docking of ACH vessicles at neuromuscular junction. Treat with antitoxin.
tetanus or lockjaw
contraction of muscles. clostridium tetanii. Death = no exhale. Toxin (tetanospasmin) carried to CNS after cleavage. Blocks release of inhibitory neurotransmitter. Requires deep cuts, (anaerobic).
non paralytic polio
spams back pain. invades meninges.
paralytic polio
produces paralysis. infects brain that controls skeletal muscles. Can recover.
salk vaccine
inactivated polio virus. Requires booster shots.
sabin vaccine
oral vaccine. Attenuated can mutate.
cryptococcus neoformans
cryptococcal meningitis. lives in soil and bird feces. produces thick capsule and melanin to prevent phagocytosis. Inhalation of spores, can affect immunosupressed bu not required. Fungal antigens in CSF.
African sleeping sickness
parasite infected bite forms lesion. fever headache, invaces cns causing meningoencephalitis. Extreme drowsiness, death. trypanosoma bruceii. Trypanosoma in blood lymph CSF.
trypanosoma bruceii
7-10 day cycle of blood titer. Changes cell surface protein, immune system compensates, changes again. Tetse fly.
spongiform encephalitis
brain has holes in it. caused by prions. scrapie or mad cow. caused by infected meat.
VCJD
abnormal enzyme fold, protein prion. changes normal proteins. No treatment available.
