Rickettsia (Intracellular) Flashcards
R. rickettsii
RMSF. Dermacenter Tick vector. Vasculitis (headache, fever, rash). Fever. Headache. Myalgia. “Rickettsia on the wRists, Typhus on the Trunk”
R. prowazekii
Epidemic typhus. “pro war”. Lice vector. Brill-Zinsser diseasae (recurrent infection). Enlargement of liver & spleen, meningoencephalitis.
R. typhi
Endemic typhus. Flea vector. Milder than prowazekii. “Rickettsia on the wRists, Typhus on the Trunk”
Coxiella burnetti
Q-fever (pneumonia + hepatitis). Endocarditis. Inhaled. Parturent animals, sheep. Involves liver and pneumonia
Ehrlichia
Intracellular – monocytes.
“Lone Star tick transmission. Closely related organism: Anaplasma phagocytophilum (intra-PMN organisms). Pathogenic to dogs & horses.
2 forms: HME (human monocytic ehrlichiosis), HGE (human granulocytic ehrlichiosis).”
Bartonella henselae
Cat scratch. Bacillary angiomatosis (AIDS). Liver lesions (peliosis) blood filled cyst.
Mycoplasma pneumonia
Sterols in cell membrane. Fried egg appearance of colonies. No peptidoglycan
Cold agglutinins
Chlamydiae trachomatis
“Can’t make it’s own ATP. Obligate intracellular. Unusual cell wall: lacks Muramic acid.
2 forms: elementary body (Eb, small, dense, doesn’t replicate, enters cell via endocytosis). Reticulate body (Rb, replicates in cell by fission)”
“Reactive arthritis. Conjunctivitis. Non-gonococcal urethritis. PID. Mucosal infections.
ABC: Trachoma – major cause of blindness. (Africa, Blindness, Chronic Infection)
D-K: PID. (Neonatal disease - birth canal)
L1-3: tight lymph nodes. (lymphogranuloma venereum)
Diagnosis: cytoplasmic inclusions seen on giemsa or fluorescent antibody stain smear.
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Chlamydiae pneumoniae
Atypical pneumonia (trans by aerosol). Association with atherosclerosis. TWAR.
Chlamydiae psittaci
Atypical pneumonia (trans by aerosol). Birds.
