Meninges & the 3 layers

Protect brain/spinal cord

• Dura Mater (outermost)
• Arachoid Mater
• Pia Mater (innermost)

Area that contains the CSF

Subarachnoid space

Meningitis

Inflammation of the meninges

Encephalitis

Inflammation of the brain

Meningoencephalitis

Inflammation of the brain & meninges

Bacterial Meningitis cardinal sign

stiff neck

How is Bacterial Meningitis diagnosed

spinal tab- CSF fluid

Bacterial Meningitis: Treatment

• Cephalosporin
• Vancomycin

3 kinds of bacterial meningitis

1. H. influenza
2. S. pneumoniae
3. N. meningitides

H. influenza Meningitis

H. influenza-B

• normal throat microbiota

H. influenza Meningitis affects what age group

6 month - 4 years old

Vaccine for H. influenza meningitis

Hib vaccine

S. pneumoniae (pneumococcal) Meningitis

S. pneumoniae

• nasopharynx carriers

S. pneumoniae (pneumococcal) Meningitis affects what age group

1 month - 4 yrs old

S. pneumoniae (pneumococcal) Meningitis has a high mortality rate in

elders (80%)

Neisseria (meningococcal) Meningitis

vaccine recommended for college students

Listeriosis

Listeria monocytogenes

• foodborne

What causes Meningitis in NEWBORNS? (transmitted to fetus)

Listeriosis

Tetnus

C. tetani - grows in deep wounds

• spams, contraction of muscles

C. tetani produces a neurotoxin called Tetanospasmin that

blocks the relaxation pathway to muscles

Tetnus vaccination

DTP (tetnus toxoid) and dT (booster)

Treatment for Tetnus

Tetnus Immune globulin

Botulism

Clostridium

botulinal toxin blocks the release of neurotransmitter, causing

flaccid paralysis

Treatment for botulism

antitoxins

Infant botulism

grows in the intestines

Wound botulism

growth of botulism in wounds

which type of botulinal toxins is most fatal?

A) Type A toxin

B) Type B toxin

C) Type E toxin

Type A toxin = 60-70% fatal

Leprosy (Hansen's Disease)

Mycobacterium

• grows best at cooler temps

Leprosy (Hansen's Disease) grows in

peripheral nerves & skin cells

Leprosy: Tuberculoid (neural)

loss of sensation in areas on skin;

• (+) lepro test

Leprosy: Lepromatous (progressive)

disfiguring nodules

• (-) lepro test

Which form of Leprosy gives a POSITIVE lepromin test?

Tuberculoid (neural)

Which form of Leprosy gives a NEGATIVE lepromin test?

Lepromatous (progressive)

Poliomyelitis (Polio)

Poliovirus

• destroys motor cells
• paralysis 1% of cases

Poliomyelitis (Polio) is transmitted by

ingestion of fecal water

Vaccination of Polio

enhanced-Inactivated Polio Vaccine (IPV)

Rabies is caused by

Rabies virus

• hydrophobia
• muscle spams

Rabies is transmitted by

animal bite (raccoon, bat, skunk)

Furious Rabies

animals are restless then highly excitable

Paralytic Rabies

animals seem unaware of surroundings

Pathology of Rabies

• virus multiplies in skeletal muscle
• moves from the PNS to the CNS
• reaches the brain, causing encephalitis
• virus enters the salivary glands & other organs

Pre-exposure prophylaxis for Rabies

Human Diploid Cells Vaccine (HDCV)

Post exposure treatment for Rabies

Rabies Immune Globulin (RIG)

Arboviral Encephalitis (Arthropod-borne viruses)

Abroviruses

transmitted by mosquitoes

Notifiable arboviral infections that cause encephalitis:

• WWW (western equine) - birds & horses
• EEE (eastern equine) - birds & horses
• SLE (St. Louis) - birds
• CE (California) - mammals
• WNV (west nile) - birds & mammals

Cryptococcus neoformans Meningitis

(Cryptococcosis)

fungal meningitis

Cryptococcosis is transmitted by

inhalation of infected bird poop

Treatment for Cryptococcosis

• Amphotericin B
• Flucytosine

2 emerging protozoan diseases

1. African Trypanosomiasis
2. Naegleria fowleri

African Trypanosomiasis is transmitted from animals to humans by

Tsetse fly

Treatment for African Trypanosomiasis blocks an enzyme necessary for the parasite

Eflornithine

Protozoan infects nasal mucosa from swimming water

Naegleria fowleri

Transmissible Spongiform Encephalopathies (TSE) are caused by

• prions

Typical prion diseases:

(Transmissible Spongiform Encephalopathies)

• Sheep scrapie
• Creutzfeldt-Jakob Disease (CJD)
• Kuru
• Bovine Spongiform Encephalopathy (BSE)

Chronic Fatigue Syndrome (CFS) is also called

Myalgic Encephalomyelitis (ME)

Chronic Fatigue symptoms:

• unexplained fatigue (at least 6 months) + 4 of these:
  • sore throat
  • tender lymph nodes
  • muscle/joint pain
  • headaches
  • unrefreshed sleep
  • malaise after exercise
  • impaired short-term memory/concentration

Bacterial Diseases of the Nervous System

• Bacterial Meningitis:
  • N. meningitis
  • H. influenza
  • S. pneumoniae
• Listeriosis
• Tetnus
• Botulism
• Leprosy

Viral Diseases of the Nervous System:

• Polio
• Rabies
• Abroviruses

Fungal Disease of the Nervous System

Cyptococcosis