Rickettsia rickettsii virulence
OMPs - bind host cells, damage = blood vessels leak
disease of R. rickettsii
Rocky Mountain Spotted Fever
2-14d after tickbite - fever, HA, malaise
macular rash from extremities to trunk/chest - change to spotted/petechial form
identification of R. rickettsii
poor gram staining - Giemsa/Gimenez stain
NAAT
MIF - detect OMP/LPS
serology
R. akari epidemiology
transmitted by mites - biphasic
cosmopolitan distribution
disease of R. akari
papule to ulcer to eschar; high fever (dif. than anthrax)
systemic spread
in blood - high fever, HA, maculopapular rash to vesicles/crust
R. prowazekii epidemiology
louse-borne typhus
d/t crowding/unsanitary conditions
R. prowazekii disease
2-30d - high fever, HA, myalgia, petechial maculopapular rash
dx by MIF
R. typhi epidemiology
typhus, common in warm/humid areas
rodents = reservoir; vector = fleas
disease of R. typhi
7-14d incubation then onset fever, HA, chills, myalgia, nausea
rash to chest/abd
Orientia tsutsugamushi epidemiology
mites - chiggers/red mites
disease of orientiatsutsugamushi
6-18d - HA, fever, myalgia
macular to papular rash on trunk - centrifugal sp. to upper/lower extremities
ehrlichia chaffeensis
intracellular in monocytes
transmitted by ticks
flu-like - HA, fever, mailaise, myalgias, late-onset rash
leukopenia, thrombocytopenia, increased transaminases
ehrlichia ewingii
intracellular in granulocytes
transmitted by ticks
flu-like - fever, HA, myalgia
leukopenia, thrombocytopenia, increased transaminases
anaplasma phagocytophilum
intracellular in granulocytes (neutrophils, eosinophils, basophils)
transmitted by ticks
flulike - HA, fever, myalgia
leukopenia, thrombocytopenia, increased transaminases
coxiella burnetii epidemiology
intracellular
SCV - spore-like, resistant & LCV
wool, dust, milk
from animals - contaminate soil - inhale airborne particles
diseases of coxiella burnetii
flu-like - fever, chills, fatigue, HA, myalgia, nausea
PNA/hepatitis
chronic Q fevers
SA endocarditis - valvular defect
identification of coxiella burnetii
serology/PCR of blood
NAAT
chlamydia trachomotis characteristics
2 biovars- trachoma and lymphogranuloma venereum (LGV)
A,B,Ba,C = ocular trachoma
D-K = urogenital trachoma
epidemiology of chlamydia trachomotis
ocular trachoma - A-C; flies, dirty clothes, fingers; blindness
urogenital trachoma - D-K
LGV - chronic STD
virulence of chlamydia trachomotis
infection based on cell receptor
LGV serovars - blood infection; replicate in monocytes, dz d/t cell detruction/inflam. cytokines
disease of chlamydia trachomotis
- LGV - painless lesions on genitals; w/ fever, HA, myalgia; sw. inguinal LN; proctocolitis
- trachoma - follicular conjunctivitis/diffuse inflammation- blindness
- adult inclusion conjunctivitis - acute conjunctivitis; mucopurulent discharge, keratitis
-
identification of chlamydia trachomotis
intracellular, Giemsa stain = polymorphonuclear cells but NOT diplococci (dif. than gonorrheae)
gram neg.
NO cx - IF/ELISA, NAAT
chlamydia pneumoniae
person-person resp. secretions
dx by MIF
dz = sinusitis/pharyngitis, bronchitis, atypical pna; mild/persistant cough/malaise
chlamydia psittaci
bird reservoir
localized infiltration - inflam. cells, necrosis, hemorrhage
Parrot fever - resp. infection; asymptomatic to severe bronchopneumonia
mycoplasma pneumoniae epidemiology
school-age kids/YA
spread in friends/family/class
virulence of mycoplasma pneumoniae
adhesins - cilia
destroy cilia/epithelial cells
can't clear airways/LRT irritation - persistent cough
disease of mycoplasma pneumoniae
tracheobronchitis
low fever, malaise, HA, dry/non-prod. cough
lymphocytes/plasma cells into bronchi cells into bronchi - PNA/atypical pna
patchy bronchopneumonia - CXR
identification of mycoplasma pneumoniae
serology/PCR
strict aerobe - cx - slow growing x 4 weeks
cx = Eaton's agar - produce mulberry-shaped colonies
epidemiology of mycoplasmatales
pleomorphic rods; membrane contains sterols
in infants, increased in F/some pre-pubertal children retain - genital mycoplasmas
diseases of mycoplasmatales
M. genitalium - nongonoccal urethritis and PIDs
U. urealyticum - nongonoccal urethritis, pyelonephritis, stillbirth/premature - gr. on cx x 24hrs
M. hominis - pyelonephritis, postpartum fever, septicemia - gr. on cx x 2-4d