micro 2 Flashcards
treponema pallidum
syphilis aerobes, attach to endothelial cells Primary -infection of vessels and perivascular area - ID50
congenital syphilis
spontaneous abortion
late stigmata
-hutchinson teeth: chalky, soft abnormally formed
-sabre shins
treponememes tx
tests
-non-treponemal agglutenation of beef- initial screen
-flourescent treponemal ABs
–false + with RA
-ABs can be detected by serology but not effective in immunity
-PCR
TX
-primary - IM of Penicillin G
–complication: Jarisch-Herxheimer reaction
—mild endotoxemia:HA, fever, hypotension
-quinolones, amioglycosides, sulfa not effectivive
Borrelia
spirochetes, microaerophiles
relapsing fevers
Lyme disease
tx with antibiotics- Jarisch-Herxheimer reaction
Borrelia recurrentis
spirochete, microaerophiles
relapsing fever
louse bourne
4-10 days high fever and hypotension
Borrelia hermsii
spirochetes, microaerophiles
relapsing fever
tick bourne
4-10 days high fever and hypotension
Borrelia burgdoferi
Lyme disease spirochetes, microaerophiles vector deer ticks bulls eye rash-> arthritis, myocarditis, dementia like responds easily to antibiotics jarisch-herxheimer reactioin
Rickettsia rickettsii
Rocky Mountain spotted fever
spirochetes, have LPS
zoonotic- dog and deer ticks
endemic to ozarks and appalachian mountains
target endothelial cells
utilize actin polymerization for locomotion like shigella and listeria
incubation 5-7 days
SX: fever, chills, HA, myalgia, rash starts on hands and feet (2-3 days later)
path: increase vascular permeability, hypovolemia, edema, ischemia, organ damage/failure; AB mediated immunity
TX: tetracyclines
ricketsia akari
spirochetes, lps
milder chicken pox disease
house mice mite vector
Ehrlichia chaffeensis
Human monocytic ehrlichia small G- cocci, obligate intracellular pathogen form vacule bound colonies-> morulae dog and lone star ticks natural hosts: deer, dogs, goats 5-10 days incubation range of symptoms like RMSF without rash
Ehrlichia equi
Human granulocytic ehrlichia; anaplasma G- cocci, obligate intracellular pathogen form vacule bound colonies-> morulae deer and dog tick vectors 5-10 days incubation range of symptoms like RMSF without rash
mycobacterium general
High wax-resistant to drying
facultative intracellular pathogens of PMN/macrophages
divide 24 hours, colonies 4-6 weeks
virulence factors
-Wax D: acid fastness, adjuvant, muramyl dipleptide
-cord factor: serpentine growth; leukocyte toxicity, trehalose dimycolate
-tuberculin: Pure protein derivative (PPD)
mycobactin: Fe chelator
sulfo-glyco and sulfolipids: prevent fusion of phagosome and lysosomes
tuberculosis disease
Ghon complex- first complex in lung with productive cough
spreads systemically: miliary TB
-granulomas in: lymphnodes, spleen, kidneys
-“millet seed granulomas in: Liver (Low O2)
Returns to apical and subapical lungs
delayed hypersensitivity 2-3 months into infection
-cycles of productive and non-productive (more prominent) cough, fevers, cachexia, night sweats
TB TX
Isoniazid (INH): mycolic acid synthesis inhbitor (always used) rifampin: RNA synthesis cycloserine: cell wall synthesis Ethambutol: cell wall? ethionamide: ? pyrazimamide: ? rifabutin: RNA synthesis
atypical mycobacterium
photochormogens: M. Kanasii
-Pigmented when in light
Scotochromogens
-Always pigmented (yellow)
-increased pigment in light
-M. scrofulaceum- cervical lymphadenitis
non-pigmented
-M. avium-intracellulare: associated with HIV
Rapid growers
-M. fortuitum: hospital associated sternal infections
M. ulcerans
Makes non protein toxin -> buruli ulcer requires surgical removal tropical disease TX: rifampin and aminoglycosides
M. leprae
obligate intracellular pathogen spectrum disease Indeterminant -one hyper/hypopigmented lesion without loss of sensation tubercoid (pauci bacillary) -multiple lesions -peripheral nerve damage -contained by Tdth Lepromatous (multi bacillary) -no immune response -deformity -blindness from loss of lashes and no blinking -localized to the surface -contagious -erythema nodosum leprosum (type III hypersensitivity) after ABx -genetic susceptibility TX: dapsoen and rifampin and clofazimine
+RNA viruses
Naked -picornaviruses -calicivirus enveloped -flaviviruses -togaviruses -coronaviruses -retroviruses
picornaviruses
- Rhinoviruses- common cold
- hepatitis A- primarily GI
- Enteroviruses
–poliovirus
–coxsackie viruses
Capsid: 3 proteins->1protomer-> 5protomers->1pentamer->12pentamers= capsid
Rhinovirus
picornavirus
replicates in URT- receptors ICAM or LDLr
not cytopathic in nasopharanx-> weak immune response
#1 cause of common cold
polio virus
picornavirus poliomyelitis vaccines -salk-killed -sabin-attenuated
non-poli enteroviruses
picornaviruses enterovirus a-d -fever, rash uri, aseptic meningitis coxsackie A and enterovirus 71 -Hand foot and mouth disease coxasckie B Pleurodynia, mycarditis and pancreatitis
hepatitis A
picornavirus fecal oral very stable Sx 4 weeks after infection (immune mediated) -fever, N/v, diarrhea, juandice DX: clinical picture+ high ALT+ IgM no tx but good vaccine
Flaviviridae
\+RNA, enveloped icosohedral 4 genera -flavi (arboviruses) --St. Louis encephalitis --West nile virus (encephalitis) --yellow fever (hemorrhagic) --dengue (hemorrhagic -hepaci: hep C -Pegi: HPgV- common commensal -Pesti: animal viruses
WNV
Flaviridae
crow-> mosquito-> humans/horses (dead ends)
encephalopathy 1%
-meningitis, encephalitis, post infection tremor, others
non-specific fever 21%
DX: IgM elisa, pcr
Dengue Virus
flaviridae Hemorrhagic dengue fever: break bone disease -rash, fever, intense muscle/joint px -masks more rare diseases in tropics Dengue hemorrhagic fever -frequently lethal -2nd dengue type cross reaction (AB dependent enhancement)
