Quiz 4 - Weller - CNS Infections Flashcards
What is meningitis?
Inflammation of the meninges
Fever, headache, stiff neck
Bacterial, viral, fungal, protozoan, parasitic
What is encephalitis?
Inflammation (swelling) of the brain
Fever, headache, stiff neck
Often viral, but can be bacterial, fungal, protozoan, or parasitic
What are brain abscesses/subdural empyema?
Similar symptoms to encephalitis
Mostly BACTERIAL
What is purulent meningitis?
Meningitis with inflammatory exudate - usually bacterial
Mostly acute
Fever, stiff neck, irritability
Can be fatal
What is chronic meningitis?
Gradual or subtle onset with progressive signs and symptoms over a period of weeks
What is aseptic meningitis?
Inflammation from an increase of cells, usually WBCs in CSF and ABSENCE of bacteria/fungi
T/F - Encephalitis is primarily viral etiology.
TRUE
Acute or chronic demyelinating diseases w/ or w/o inflammation can happen
Idiopathic encephalitis
What is meningoencephalitis?
Pts with both meningeal and encephalitic manifestations
What are the 4 routes leading to a CNS infection?
Hematogenous
-Blood
—Viral, bacterial, fungal
Contiguous focus
-Sinus, ear, face, oral cavity
—Bacterial
Direct inoculation/iatrogenic
-Trauma, surgery, lumbar puncture, congenital defects
—Bacterial
Nervous system
-Infection of systemic nn, retrograde movement to brain
—Viral
What is contiguous focus exposure?
Any infection close to the CNS that spreads to the CNS - NOT BY BLOOD
- Otitis media
- Mastoiditis
- Sinusitis
What is a great example of a viral CNS direct inoculation?
Rabies virus
-Transmitted to peripheral neurons and travels via retrograde transport to CNS
If there is a CSF infection, what do we look for, compared to normal values?
Bacterial
- High WBC (Lots of PMNs)
- LOW GLUCOSE
- HIGH PROTEIN
- High opening pressure
Viral
- High WBC
- NORMAL GLUCOSE
- NORMAL PROTEIN
- High opening pressure
Fungal
- Very High WBC
- LOW GLUCOSE
- HIGH PROTEIN
What is the most common type of meningitis?
VIRAL
Usually less severe than bacterial
Usually resolves on its own w/o treatment
Fever, headaches, stiff neck
What is the most common cause of viral encephalitis?
Viruses
Fever, headache, altered cognition, seizure
What are enteroviruses?
Most common cause of viral meningitis
*Especially active in the SUMMER and FALL months in children less than 15 years old
Tell me about HSV meningitis.
Major cause of viral meningitis, 2nd only to enteroviruses
*In adults, majority of cases of meningitis are due to HSV-2
HSV-1 is responsible for 90% of cases of ____ __________.
HSV encephalitis
T/F - Varicella-Zosters Virus (VZV)is suspected in the presence of concurrent chickenpox or shingles, but also linked to meningitis and encephalitis w/o VZV characteristic rash.
TRUE
____ _________ may produce aseptic meningitis, w/ or w/o associated infectious MONOnucleosis.
EBV infections
S Caleb Freeman
What should be suspected in any pt presenting with a viral meningitis w/ known or suspected risk factors for HIV infection?
HIV meningitis
This can occur following primary infection with HIV in 5-10% of cases and less commonly at later stages of illness
What is considered when clusters of meningitis and encephalitis cases occur in a restricted geographic region during the SUMMER or early FALL?
Arboviral meningitis
What is the classical presentation of encephalitic rabies?
Fever, fluctuating consciousness, autonomic hyperactivity
Newborns are at risk for meningitis via what organisms?
Group B strep/S. Agalactiae - GPC
E. coli - GNR
L monocytogenes - GPR
Klebsiella
Infants and children are at risk of meningitis via what organisms?
S. Pneumoniae - GPC
N. Menigitidis - GNDC
H. Influenzae - GNR
Adults are at risk for meningitis from what organisms?
Strep pneumoniae
N meningitis
Difference b/t beta and alpha hemolysis.
Beta - Clear zone around bacterial colony. Complete lysis
Alpha - greenish-brown colored halo around colonies. Partial lysis
Strep pneumoniae is known to cause what and where is it acquired?
Pneumonia, meningitis
Normal oropharyngeal flora, aspiration to lungs/other parts of body
Transmission to CNS may result in meningitis
What organism is the leading cause of sepsis and meningitis in the first few days of life for neonates?
Group B strep
Found in lower GI and/or vaginal flora of 10-40% of women
Can colonize the newborn if amniotic sac breaks and is open for longer than 18 hours and/or in the vaginal flora
What is another organism that commonly causes newborn meningitis?
E. coli
From vaginal flora
__ _________ is strictly a human pathogen and found in nasopharyngeal flora of 20-80% of healthy people.
H influenzae
Meningitis occurs in children in 2 years of age
Immunization has dramatically reduced disease
What G- bacterium, that is usually found diplococcus and is exclusively a human parasite?
Neisseria meningitidis
Nasopharyngeal colonization common
*Common in pyogenic meningitis in all but most often in children
T/F - Listeria monocytogenes is a G+ rod that is beta hemolytic and spread in soil ground water, decayed veggies, and GI tract of animals we eat. It can grow at fridge temps.
TRUE
T/F - In 2006, the FDA authorized listeria-specific bacteriophage to be added to food products to combat listeria infections.
TRUE
What does listeria monocytogenes cause, how acquired, and symptoms?
Meningitis in newborns and immunocompromised
Dairy, meat, vegetables
Bacteremia, headache, stiff neck, confusion, convulsions
Mycobacterium tuberculosis causes what?
Tuberculosis
Other than tuberculosis, what else does mycobacterium TB cause?
Tuberculous meningitis - from the blood spread of primary or post primary TB
Also can be acquired via exposure to individuals with active TB
T/F - Fungal pathogenesis is similar to bacteria, and most fungi are opportunists.
TRUE
Cryptococcus neoformans causes what?
Associated CNS involvement/meningitis development in immunocompromised pts
These infections are rare in healthy people
T/F - Syphilis is a spirochete.
TRUE
How is syphilis acquired?
STD
Primary infection is genitalia, secondary spreads beyond initial infection site
Can cause neurosyphilis
Headache, nausea, vomiting, neck stiffness, etc.
Lyme borreliosis is caused by _______ ___________.
Borrelia burgdorferi
What does Lyme disease cause?
Meningitis and/or chronic encephalopathy
Transmitted by 14 species of tick
Skin lesion, erythema, can spread to CNS
What are prions?
Protein molecules that have conformational changes of a normal prion protein (same protein, different folding/structure)
**Protein material that can fold in multiple, structurally abstract ways, at least one of which is transmissible to other prion proteins, which leads to disease comparable to a viral infection
Example: Creutzfeldt-Jakob disease
What are three examples of immunosuppression?
HIV, post organ-transplant, immunosuppression therapies
Tell me more about immunosuppression.
Reactivation of lantern infections
-EBV, VZV, CMV
Opportunistic susceptibility
