Lecture 11 Flashcards
What organisms spread via vectors?
Borrelia
Rickettsia
Yersinia Pestis
Borrelia shape and stain
Long spirochetes
GramNeg, NO LPS!
What does borrelia have in place of LPS?
Inflammatory lipoproteins in OM
B. recurrentis, B. hermsii, 20 others cause what?
Recurrent fever
B. recurrentis, B. hermsii, 20 others (recurrent fever) symptoms?
Sudden onset fever
Intense headache
Muscle pain
SYMPTOMS RECUR EVERY 5-10 DAYS
What causes recurrent fever via B. recurrentis, B. hermsii, 20 others?
Antigen keeps switching
New lymphocytes have to be made on a cyclic basis
What can B. recurrentis, B. hermsii, 20 others lead to after recurrent fever?
Necrotic foci in parenchymatous organs
B. burgdorferi + 9 others cause what?
Lyme disease
Lyme disease initial symptoms
Flu-like symptoms
erythema chronicum migrans
Lyme disease secondary symptoms
facial nerve palsy
meningitis
carditis
B. recurrentis spreads how?
Lice
B. hermii spreads how?
Soft-bodied ticks from rodent reservoir
many infected ticks out west, but outbreaks are rare
B. burgdorferi spreads how?
Transmitted by deer ticks
What protein on B. recurrentis, B. hermsii is the one with variation?
VMP protein antigen
How do you treat recurrent fever?
Doxy or synthetic PCNs
Can use 3 gen ceph to treat recalcitrant infections
Shape and stain of rickettsia
Small rods
Gram Neg
Rickettsia metabolism
Obligate intracellular parasite
What are the four types of rickettsia
Typhus
Spotted fever
Ehrlichia/anaplasma
Coxiella burnetti
Where do typhus group rickettsias grow
Host cytoplasm
Where do spotted fever group rickettsias grow
Host cytoplasm
Organism has a common lifecycle to chlamydia
Ehrlichia and anaplasm group rickettsias
What do ehrlichia and anaplasm group rickettsias lack?
No PG or LPS
How does typhus group rickettsia cause illness?
Parasite of blood endothelium –> vasculitis
Begins on chest and moves to extremities
Severe prostration and high fever
R. akari causes smallpox-like rash
What bug causes spotted fever type rickesttsia
R. rickettsii
R. rickettsi (spotted fever type) causes illness how?
Endothelial pathogen
Rash on extremities that moves to trunk
What special disease belongs to spotted fever type rickettsia
Rocky Mountain Spotted fever
Rocky mountain spotted fever symptoms
Abrupt fever HA N/V Myalgias, arthralgias Abodominal pain due to vasculitis of organs (50% fatal without treatment)
Ehrlichia chaffeensis (monocytic erlichiosis, HME) causes illness how?
Obligate parasite of monocytes and macrophages
Pathology from immune response
Ehrlichia chaffeensis (monocytic erlichiosis, HME) symptoms?
HA Myalgias Thrombocytopenia Lymphopenia Bone marrow granulomas Like RMSF but without vasculitis
Anaplasma phagocytophilum (anaplasmosis, HGA) sypmtoms?
Maybe rash
Symptoms like Ehrlichia
How does Anaplasma phagocytophilum (anaplasmosis, HGA) cause illness?
Obligate parasite of neutrophils and granulocytes
Pathology from immune response
Coxiella (Q-fever) resembles what?
resembles influenza or pneumonia rather than typhus
Chronic coxiella can lead to what?
Endocarditis in PTs with defective heart valves
Typical presentation of coxiella?
Fever with pneumonia/hepatitis 2-3 weeks after exposure
What two bugs cause typhus group rickettsial infection and how do you get each?
R. prowazekii-human lice
R. typhi-rat flea
Prevalent where hygiene is low
Where is spotted fever common and how do you get it in each place?
East US-dog tick
West US-wood-tick
Ehrlichia and Anaplasma are spread how?
Ticks
Coxiella burnetii (Q-fever) is spread to humans how?
Dust or aerosal from infected animals-goats, cattle, sheep, cats (even though it is spread to other animals via ticks)
Coxiella burnetti attacks what part of the body?
Lung epithelium
How do rickettsias attack blood vessels?
Phospholipase A targets cell membranes to lice blood vessels and other epithelium
R. Rickettsii also attacks smooth muscle
What is the treatment for rickettsial infections
Tetracycline/doxycycline
