Neuro Microbio

Question 1

Label each of the following gram + or gram -

1) Staphylococcus
2) Streptococcus
3) Neisseria
4) Clostridium
5) Corynebacterium
6) Bacillus
7) Listeria
8) Mycobacterium
9) Campylobacter
10) Haemophilus
11) E. coli

Answer 1

1) gram +
2) gram +
3) gram -
4-8) gram +
9) gram -
10) gram -
11) gram -

Question 2

What 3 organisms causing meningitis have vaccines containing polysaccharide capsule antigens are conjugated to a carrier protein, enhancing immunogenicity by promoting T- cell activation and subsequent class switching?

Answer 2

HiB vaccine
Meningococcal vaccine
Pneumococcal vaccine

Question 3

Campylobacter jejuni

• Cause
• Transmission
• Diseases

Answer 3

• Minor cause of bloody diarrhea, especially in children
• Fecal oral transmission through foods
• Guillian Barre syndrome

Question 4

Lyme disease

• Cause
• Symptoms
• Treatment

Answer 4

• Boriella burgdorferi (common in northeastern US)
• Early: Flu like symptoms, erythema chronicum migrans, and facial nerve palsy
• Later: monoarthritis and migratory polyarthridis, cardiac (AV nodal block), neurologic (encephalopathy, facial nerve palsy, polyneuropathy)

FAKE a key Lyme pie (Facial nerve palsy, arthritis, Kardiac Block, Erythema migrans)

-Treatment: doxycycline, ceftriaxone

Question 5

Cryptococcus neoformans (heavily encapsulated yeast)
Causes what?
Found where?
How is it acquired?
How is it stained?

Answer 5

• Cryptococccal meningitis
• Soil, pigeon droppings
• Acquired through inhalation (spores) with hematogenous dissemination to meninges
• India ink and mucicarmine, Latex agglutination test detects polysaccharide capsular antigen (more specific)

Question 6

Herpesvirus
Envelope: yes or no?
DNA structure: 
Medical importance
HSV-1?
HSV-2?
VZV

Answer 6

Yes
DS and linear
HSV-1-oral (and some genital lesions), spontaneous temporal lobe encephalitis (most common cause of sporadic encephalitis in the US), Latent in trigeminal ganglia. Transmitted by respiratory secretions, saliva. keratoconjunctivitis
HSV-2-genital (and some oral) lesions–>latent in sacral ganglia
HHV-3 (VZV)-chickenpox, zoster (shingles); vaccine available–>latent in dorsal root or trigeminal ganglia.

Question 7

EBV

Answer 7

Mononucleosis. Fever, hepatosplenomegaly, pharyngitis, and lymphadenopathy
Transmitted by respiratory secretions and saliva; called “kissing disease”
Infects B cells, atypical lymphocytes.
Associate with Hodgkin lymphoma, endemic Burkit lymphoma, nasopharyngeal carcinoma

Question 8

Rabies virus
Characteristics?
Location?
Transmission?
Disease progression?
Additional info

Answer 8

-Bullet shaped virus/negri bodies
-commonly found in purkinje cells of cerebellum and in hippocampal neurons
-bat, raccoon, and skunk bites than from dog bites in US
-Fever, malaise–>agitation, photophobia, hydrophobia–>paralysis, coma–>death.
-Long incubation period before symptom onset.
Postexposure treatment is wound cleansing and vaccination +/- rabies immune globulin. Travels to CNS by migrating in retrograde fashion up axons

Question 9

Neurologic (findings/labs, pathogen)

Abscesses-Many ring-enchancing leasions on imaging, CD4+<50 cells/mm3,

Answer 9

• Toxoplasma gondii
• , directly associated with HIV
• JC virus reactivation (PML)
• Crytococcus neoformans

Question 10

Common causes of meningitis

1) Newborn (0-6 months)
2) Children (6 months-6 years)
3) 6-60 years
4) 60+ years

Answer 10

1) Group B streptococci, E. Coli, Listeria
2) S. Pneumoniae, N. meningitidis, HiB, Enterovirus
3) S. Pneumoniae, N. meningitidis (#1 in teens), Enterovirus, HSV
4) S. Pneumoniae, Gram- rods, Listeria

Question 11

What do you give for medication for meningitis?

Answer 11

Ceftriaxone and vancomycin empirically (add ampicillin if Listeria suspected)

Question 12

Viral causes of meningitis?

Answer 12

enteroviruses (#1 especially coxsackievirus), HSV-2, HIV, WNV( most common cause of epidemic encephalitis), VZV

Question 13

In HIV immunocomprimised state causes of meningitis

Answer 13

Crytococcus, CMV, toxoplasmosis (Brain abscess), JC virus (PML)

Question 14

Listeria Monocytogenes
Acquired from what?
Causes?
Treatment?

Answer 14

• acquired by ingestion of unpasteurized dairy products and deli meats, via transplacental transmission, or by vaginal transmission during birth.
• Neonatal meningitis, meningitis in immunocompromised individuals
• ampicillin

Question 15

CMV
Characteristics?
Causes?
Transmission?

Answer 15

• “owl-eye inclusions”. Latent in mononuclear cells
• congenital infection, mononucleosis, pneumonia, retinitis
• congenitally and by transfusion, sexual contact, saliva, urine, transplant.

Question 16

Toxoplasma
Disease?
Transmission?
Diagnosis?
Treatment?

Answer 16

• Brain absecesses in HIV (seen as ring enhancing lesions on CT/MRI), congenital toxoplasmosis= “classic triad” of chorioretinitis, hydrocephalus, and intracranial calcifications
• Cysts in meat or oocysts in cat feces; crosses placenta (pregnant women should avoid cats)
• Serology, biopsy (tachyzoite)
• Sulfadiazine + pyrimethamine

Question 17

HSV identification?

Answer 17

Viral culture for skin/genitalia.
CSF PCR for herpes encephalitis
Tzank test (smear of an open vesicle to detect multinucleated giant cells)
Infected cells have intranuclear Cowdry A inclusions.