Ch. 22 Microbe Diseases of the nervous system Flashcards
Does the NS have a microbiota?
No! So any microbes in there is probably bad news
Meningitis
Swelling/inflammation of the meninges, that can be caused by an infection
Encephalitis
Inflammation of brain
Bacterial diseases
Bacterial meningitis. Caused by three we have to memorize:
- Neisseria Meningitides
- Haemophilus Influenzae
- S. Pneumoniae
Pathway and details of bacterial NS infection
Bacteria infect Mucous membranes –> get into bloodstream –> get into spinal fluid.
Spinal tap needed to asses infection. Death can occur within hours so a broad-spectrum lipid soluble (to cross barrier) antiinfective in administered immediately.
Aseptic (VIRAL) meningitis
Caused by viruses. More mild, and palliative care is usually used. Patient should recover.
Listeriosis
Caused by Listeria monocytogenes. Not obligate, but CAN and WILL live inside macrophages, making them harder to detect.
Listeriosis transmission & pregnancy complication
- Secreted in animal feces & urine.
- Foodborne & can grow in fridge (its a psychrotroph).
- If pregnant when infection starts, causes 60% infant mortality rate
Tetanus Causes
- Microbe: Clostridium Tetani.
- Tetanospasmin (exotoxin) causes “spastic paraphysis” where both muscle agonist and antagonists contract at the same time (exp: lockjaw).
- Takes a very small amount for it to work on body
Tetanus vaccine & treatment
- Its the “T” in the DTaP vaccine.
- Tetanus toxoid
- Treatment is the tetanus antitoxin (TIG) & tetanus toxoid later on
- Recovery does not result in immunity. There is not enough antigens in the body to produce a primary response. Only enough toxins to produce disease.
Botulism (recovery also DOES NOT mean immunity) & treatment
- Clostridium Botulinum
- A, B, E, neurotoxins (exotoxins) cause flaccid paralysis.
- Treatment: Palliative & antitoxin
How botulism develops & what to do w/ food
- Happens when you ingest improperly canned/preserved food. The scottish dish haggus is a prime example of what not to do with food.
- Prevention: acidity prevents some of its growth, boiling canned things for 10 mins, not eating dented cans etc.
Can you give infants honey?
No! Sometimes C. botulidim is in honey in small amounts. Normal ADULT microbiota crowd out/destroy the botulidim. But infants don’t have a developed microbiota so they can develop infant botulism.
Leprosy (Hansen’s Disease)
- Mycobacterium leprae & M. lepromatosis (prob a mutation from original)
- Not highly contagious
- Transmission: Direct contact with nasal secretions
- Treatment: Chemo for a long period of time. However, not contagious within 3 days of treatment.
Tuberculoid form of leprosy
- Mild
- can lead to lepromatous (severe)
Lepromatous form of leprosy
- You lose cartilagenous parts of your body because the microbe grows best in colder-than-core-temps of your body. So toes, fingers, etc where temp is cooler.
- Hides in macrophages
Viral diseases - polio brief details
- Affects peripheral nerves. can cause paralysis.
- Iron lung = used if person’s respiratory muscles are paralyzed. Some people recovered.
- Severe epidemics in summer. Had to keep kids at home.
Polio important details
- proper term: Poliomyelitis
- Poliovirus
- Fecal –> oral route
- Vaccines:
- Salk vaccine (IPV). Effective. needed boosters
- Sabin vaccine (OPV). Attenuated vaccine. Less boosters.
Rabies
- Rabies virus
- Portals of entry:
- Parenteral route: proliferates in PNS then travels to the
CNS. - Aerosols. Mainly in rabies labs.
- Parenteral route: proliferates in PNS then travels to the
- Thought of water can cause spasms. Untreated = death.
Rabies Treatment
- PEP. Post exposure prophylaxis.
- Rabies is slow growing so PEP will allow for antibody neutralization from one’s own immune response.
- Pasteur made the first rabies vaccines. sacrificed bunnies.
Rabies vaccines & treatments
- HDCV. Rabies grown in cell cultures. 4 injections. At 3, 4, & 17 days.
- RIG. Rabies antibodies. Passive immunity.
- Milwaukee protocol. Infected person is too far into infection and has not received vaccines soon enough. Put them into a coma and give them anti-viral drugs. Has worked for some people.
Vertical transmission
- Not all pathogens can cross the placenta
- those that can:
- Group B. Streptococcus
- Listeria monocytogenes
….others…. - Can cause preemie, enlarged head and cognitive disorders
Torch screening test
- Testing done for diseases that can affect fetuses
- T: toxoplasmosis
- O: other…syphillus, HIV, Chickenpox, Measles
- R: Rubella
- C: Cytomegalovirus
- H: Herpes simplex virus
Protozoan diseases - African trypanosomiasis (Sleeping sickness)
- Trypanosoma brucei gamiense (Humans only reservoir)
- T.b. rhodesciense (resovoir: domestic and wild animals)
- Vector: Tsetse fly
- S/S: Fever, headache, deterioration of CNS
