Exam 3 Flashcards
Streptococcus pneumoniae
Virulence: CASPSULE IS KEY!! Adhesins (pspA, CpbA) IgA protease, Pneumolysin, Autolysin,
Gram+ lancet shaped diplococcic Catalase- Alpha hemolytic Optochin sensitive Bile soluble Quellung Rxn
Bacterial meningitis + acute otitis media + sinus infection
Neisseria Meningits
LOS AND CAPSULE
Meningitis + hemorrhagic rash w/ petechiae (reflecting septicemia- LOS)
Gram- cocci in pairs
Fastidious, chocolate agar
oxidase+, sugar fermentation to acid (gluc and mal)
Haemophilus Influenzae B
Gram- pleomorphic coccobacilli facultative anaerobe may or may not be encapsulated Fastidius growth- chocolate V and X College outbreaks
Mycobacterium Tuburculosis
Rare- chronic bacterial meningits
Two Step process: droplet inhalation, infect lung macrophages, move to blood via lymph, then to CNS
Burrelia Bugdorferi
Lyme Disease (bacterial encephalitis)
Spirochete, microaerophilic
diff to culture, needs BSKII
Aseptic, Bulls eye
Treponema Pallidum
Tertiary Syph
Difficulty coordinating muscle movement, paralysis, numbness, gradual blindness, dementia
gram- spirochete
Campylobacter Jejuni
Gram-, microaerophilic, motile
Guillain Barre- demylenating disorder characterized by immunologic attack on peripheral nerve myelin due to cross reactivity between microbial ganglioside-like epitopes in the LPS that react with neural antigens.
Polymicrobial Abscesses
Most often Strep
localized suppurative lesion, space occupying lesion- compresses structures
headache, drowsiness, confusion, hemiparesis, seizures, speech difficulties, fever, NO STIFF NECK
Dx: Ring on CT
Cryptococcus Neoformans
FUNGAL
pulmonary–>latent
Virulence- melanin (protects against ox defense of macrophages), phosphlolipase B, inflamm response
Pigeon excreta + Rotting wood Gram+ Yeast India Ink + Calcofluor white + urease + capsular antigen
Cocciodes Imitis
Valley Fever-fungus
arthrocondia transform into spherules
resp–chronic pulmonary condition–disseminate to meninges, bones, joints, subcut and cut
SW, MIMIC TB huge yeast.
outbreaks in dust storms, earthquakes, earth excavations
Histoplasma Capsulatum
North American Histoplasmosis- fungus
inhal macroconidia from soil
central and southern US, large inoculum. benign in normal.engulfed (live inside macro) ring enhancing lesion. huge yeast, mimic TB)
Trypanosoma Cruzi
Chagas Disease (parasite)
Bite from Triatome bug, southern US to southern Argentina.
Initial sore, followed by fever and acute enceph, chronic disease later and affect heart, colon or nervous system
plasmodium falcipurum
Malaria- KEY = ICAM
infects liver and RBC
acute widespread disease accompanied by recurrent episodes of fever, chills, anemia = malarial fever
can travel to CNS and cause brain lesions and coma
cerebral malaria FATAL 24-72 hrs
Neonatal Menningitis
GROUP B STREP
Nuchal rigidity
classic meningitis
Petechiae distinguish…
Neisseria
Haemophlis Influenzae shape
Pelomorphic gram negative cocobacilli
What’s in the CSF bacterial meningitis?
LOW glucose, HIGH protein, Polys (PMN)1
On what media does Neisseria grow?
Thayer-Martin
On what media does Ecoli (enteric) grow?
MaConkey
Picornavirus Genome
NONenveloped, ss+RNA,
5’ UTR with IRES, covalently linked to VPg
3’ UTR short with polyA tail
p1 capsid
Which pico viruses types encode a leader protein?
Apthoviruses and cardioviruses
What is the role of eIF-4G?
Cleavage of this protein results in HOST CELL protein synthesis shut off
Pico Viral NS Protein 2A
Viral Protease: Polyprotein cleavage
pViral NS 2B
enhances vesicle formation in host cells, SITES of RNA synthesis
pv ns 2C
RNA helicase
pv ns 3ab
stimulates 3D polymerase activity
stimulates proteolytic activity of 3CDpro
pv 3C
Viral Protease
pv 3D
RNA dep RNA polym
RNA synthesis
VPg
Provides poly U primer for 3D fxn
Poliovirus
Flaccid paralysis results from destruction of motor neurons in the anterior horn of spinal cord
SALK VACCINE
Inactivated poliovirus vaccine. IPV less GI immunity.
SABIN Vaccine
Live! highly effective! oral! lifelong
Cocksackie A and B groups
Cause aspetic meningitis
group A cocksackie ALSO
Herpangina- sudden onset fever + ulcers
a16- HFMD
type 1 diabetes?
What do Apthoviruses cause?
Foot and mouth disease in animals. (FMD)
What are the two families of arboviruses?
Flavivirus and Togaviridae
Flaviv have 3 genera- flaviv/pesti/hepaci
Flavivirus structure and genetics?
Envelope (host cell receptor binding), 3 struc proteins (env, prM, C), M separates from prM upon maturation. ONLY GENERA with 5’ cap. none have tail.
what stimulates flaviviral core disassembly?
pH induced change
Flavi NS1
elicits humoral immune response
flavi NS2A + NS2B
RNA Synthesis
flavi NS3 analagous to what Pico protein?
Viral protease
anal to L,2A,3C
flavi NS4A + NS4B
RNA Replication
NS5 + analogous Pico Protein?
RdRp
pico 3D
Flavivirus C protein analogus pico protein?
VP1, VP2, VP3, VP4
FLAVIVIRAL DISEASES
WNV, YELLOW FEVER, DENGUE FEVER, STL ENCEPH, HEPC
What is different about the Togavirus genome??
Nonstructural proteins are at the 5’ end
Structural proteins are at the 3’ end
Defining characteristics of Rhabodovirus?
Large, bullet-shaped virion
- ssRNA
RNP most infectious part
Rabies!!
