22 - Nervous system infections Flashcards
Bacterial meningitis symptoms
fever, headache, stiff neck; convulsions, coma
What are the different organisms that cause meningitis?
bacteria, virus, fungi, protozoa
What is the treatment for bacterial meningitis?
start on broad spectrum antibiotics proactively while waiting on spinal tap results
What is the most common type of meningitis?
viral meningitis - but is less severe
What are the 3 main bacteria that cause meningitis?
- Haemophilus influenzae (Hib)
- Neisseria meningitidis
- Streptococcus pneumoniae
Haemophilus influenzae
- used to be most common but not now from vaccine
- normal microflora of throat
- gram negative
- sugar capsule
Neisseria meningitidis
- gram -
- capsule
- normal microflora of throat
- transmission from droplet aerosols or direct contact
- endotoxin (rapid death - hours after fever)
Streptococcus pneumoniae
- aka pneumococcal meningitis
- gram +
- capsule
- leading cause of bacterial meningitis now
What causes listeriosis?
Listeria monocytogenes bacteria (lives and proliferates inside macrophages)
Symptoms of listeriosis
-adult: usually mild but can develop into meningitis (4th most common) usually in immunocompromised
- pregnancy: mom mild flu-symptoms, fetus can be stillborn/miscarriage
How is listeriosis transmitted?
foodborne (deli meats/dairy) and animal feces - grows at food temp
What is the treatment for listeriosis?
antibiotics
Cryptococcus:
- caused by cryptococcus neoformans
- fungal infection
- leads to meningitis (in immunocompromised
- facultative intracellular pathogen
- transmitted through inhalation
- antifungals
Tetanus organism
Clostridium tetani (bacteria)
Tetanus transmission
soil/animal feces
Tetanus symptoms
toxin blocks relaxation leads to spasms, lockjaw, and death
Tetanus treatment
vaccine (DTaP)
What is the neurotoxin for tetanus?
tetanospaspmin (released when bacteria die)
Botulism
- Clostridium botulinum (bacteria)
- soil/aquatic/sealed cans
- exotoxin it produces causes diseae
- flaccid paralysis (difficulty swallowing, weakness, blurred vision, respiratory/cardiac failure/ death)
- blocks ACH
What is the treatment for botulism?
antitoxin - horse derived with many side effects
Leprosy
- mycobacterium leprae (bacteria)
- invades PNS and causes nerve damage from cell mediated immune response
- 2 forms of disease (tuberculoid and progressive)
- communicable but not very contagious
- long incubation period
- antibiotics
What is polio caused by?
polio virus (piconraviridae)
How is polio transmitted?
contaminated water in poor sanitation
What are the symptoms of polio?
- 3/4 don’t have symptoms
- mild: headache, sore throat, fever
- severe: (1%) death by respiratory paralysis
What is the treatment for polio?
vaccine (needle/oral)
What causes rabies?
Rabies virus (rhabdoviridae)
What are the symptoms of rabies?
rage, fatal encephalitis, paralysis, swallowing difficult
What is the transmission of rabies?
infection through bite of animal
What is the tx for rabies?
- long incubation so can have a vaccine post-exposure
- once symptoms have onset - can induce coma - there are antiviral drugs but almost always fatal
What are the 4 most common animals that cause rabies?
bats, skunks, foxes, raccoons
Sleeping sickness organism
Trypanosoma brucei - protozoa
How is sleeping sickness spread?
tsetse flies (incubation weeks-months)
Symptoms of sleeping sickness
fever, headaches, CNS deterioration - coma or death with no tx
TX of sleeping sickness
moderately effective drugs - can’t alter disease once CNS is involved
West Nile Virus
-Flaviviridae
- arbovirus
- bird-mosquito-human cycle
- fever, headache, weakness, tremors, paralysis or encephalitis - most cases mild
