Yersinia - Spirillum Flashcards
This is a Gram (-) rod that exhibits bipolar staining (looks like safety pin). It is a lactose non-fermenter and is oxidase negative and urease negative. Colonies look like a fried egg.
Yersnia pestis
Yersnia pestis is a bioterrorism threat transmitted from rodents to humans by ____
fleas
Yersnia pestis causes Bubonic plaque. Describe the incubation, symptoms and progression.
incubation: 2-8 d
symptoms: fever, chills, myalgia, arthralgia, HA, within 1 day proximal lymph node becomes tender, enlarging into a pianful bubo (large black bulge)
progression: sepsis and multiorgan failure
What two diseases does Yersnia pestis cause?
Bubonic plague and Pneumonic plague
Describe the incubation period and symptoms of Pneumonic plague caused by Yersnia pestis
incubation: 2-4 d
symptoms: fever, chills, myalgia; becomes more severe after 1 d; bloody sputum, chest pain, dyspnea, cyanosis, death by 24 h
note: can be transmitted from person to person (terrorist attack)
The LPS/endotoxin is a virulence factor of Yersnia pestis that is important in sepsis. How does it work?
travels to lymph nodes via lymphatics, infects monocytes and disseminates throughout the body (bacteremia)
This is a very small Gram (-) rod. It is ID’d on patients from endemic areas with symptoms; blood/tissue gram stains (weakly stain); requires cysteine or cystine; has unique long chain fatty acids.
Francisella tularenis
Francisella tularenis grows on ____ agar in 3-5 days
BYCE
note: also grows on chocolate agar
How is Francisella tularenis spread?
contact with infected animals - rabbits and squirrels tick bites (no human to human spread)
Francisella is a bioterrorism threat because why?
it can be aerosolized
This disease cuased by Francisella tularenis starts with sudden onset of fever, myalagia, arthralgia. There are several froms based on clinical manifestation: ulceroglandular (cutaneous ulcer and lymphadenopathy), oculoglandular, typhoidal, pneumonic, oropharyngeal, and GI.
Tularemia (rabbit/tick/deer fly fever)
Francisella lives intracellularly. How does it survive?
survives in macrophage by preventing phagosome lysosome fusion
In regard to virulence factors, virulent strains of Francisella are ____
encapsulated
The Francisella antigen can cross-react with _____
Brucella
This is a Gram (-) coccobacilli that requires high CO2. It has 3 species.
Bartonella sp.
For each of the following species of Bartonella, describe how its transmitted:
B. quintoana
B. bacilliformis
B. henselae
B. quintoana: body louse
B. bacilliformis: sand fly
B. henselae: cat scratch
For the following disease, give the species of Bartonella that causes it and the symptoms: Trench Fever
B. quintana - severe HA, fever, weakness, pain in long bones, fever recurs in 5 days (10-12 episodes); may cause bacteremia and endocarditis
For the following disease, give the species of Bartonella that causes it and the symptoms: Bacillary Angiomatosis
B quintana and B. henselae - vascular proliferative disorder in AIDS/IC; skin lesions may ulcerate and drain (Dx: pcr)
For the following disease, give the species of Bartonella that causes it and the symptoms: Cat Scratch Disease
B. henselae - 2-3 days after a cat scratch, a papule develops and progresses to a vesicle; the lesions persist 1-3 wks; chornic proximal lymphadenopathy 2-3 wks later that persists for months
For the following disease, give the species of Bartonella that causes it and the symptoms: Carrion’s Disease - Oroya Fever and Verrugo Peruana
B. bacilliformis - transmitted by sand fly in Andes Mts. - bacteria invade RBCs -> serious anemia, muscle/joint pain, fever, HA, coma, followed by chronic cutaneous lesions
This is a Gram (-) coccobacilli. It grows well on blood agar. It is commensal in URT of domestic pets and is given to humans via animal bite, scratch, or lick (similar to cat scratch fever)
Pasteurella multicida
Local cellulitis or lymphadenitis, Septicemia, and local septic arthritis are all disease caused by what bacterium?
Pasteurella multicida
This bacterium has 2 species: S. moniliformis and S. minus. It is a Gram (-) long thin rod.
Streptobacillus
How is S. moniliformis ID’d?
has L shaped colones
How is S. minus ID’d?
darkfeield or giemsa smears (spaghetti and meatballs appearance)
Where is Streptobacillus usually found? How is it transmitted to humans?
nasopharynx of rats or other small rodents - humans get it from bite or bodily secretions of the rodents
What disease does Streptobacillus cause? Give incubation period and symptoms.
Rat Bite Fever
Incubation: 2-10 days and then abrupt onset
symptoms: fever, HA, chills, muscle pain and migratory polyarthralgias and rash on abdomen and feet
What is the diagnostic triad associated with Rat Bite Fever?
rash, rate bite, and migratory polyarthritis
