Lc 14

Question 1

Explain the structure of spiroshetes

Answer 1

-Corkscrew shaped
-family leprospira has hooked ends
-flagella inside the outermembrane(periplasmic flagella )

Question 2

What are the four pathogens of spirochetes?

Answer 2

Treponema, borrelia, leptospira, borreliella

Question 3

Treponema is genetically monomorphic organism.what does monomorphic mean?

Answer 3

Different genomes of treponema is 99.9% similar.

Question 4

Explain what kind of infection syphilis is and it early and late manifestation

Answer 4

STP, early : involve skin
Late: all organs and tissue sites, and central nervous system

Question 5

What is main habitat of syphilis and is it able to do metabolism by itself?

Answer 5

Human, no it highly depends on host cells—> they cannot make fatty acids, nucleotides, amino acids by themselves.

Question 6

Syphilis is highly invasive. How does it transmit throughout the body?

Answer 6

Gain access to blood and disseminates throughout body, and CNS.

Also, cross placenta and cause congenital syphilis

Question 7

How do syphilis persist in human body?

Answer 7

Antigenic variation

Question 8

Does infection get eradicated systemically?

Answer 8

No, it causes lifelong , chronic infection in untreated persons

Question 9

What are some bacterial antigens?

Answer 9

LPS, peptidoglycan, bacterial cell wall

Question 10

How could syphilis be a chronic infection? What is their method?

Answer 10

They change their antigens (antigenic variations) through gene conversion. They have TprK which has 7 variable regions for gene conversion.

Question 11

How do we treat syphilis?

Answer 11

First line: penicillin
Alternatives : doxycycline, tetracycline, amoxicillin
Macrolides no longer used bc it resistance

Question 12

How do we identify syphilis(treponema pallidum)?

Answer 12

Dark field microscopy, serologic testing(checks for the presence of antibodies)

Question 13

What kind of disease does B.hermsii cause?

Answer 13

Relapsing fever

Question 14

How do people get borrelia?
.

Answer 14

They get tick or Lise bites

Question 15

Name diff. Types of borrelia according to their original of infection

Answer 15

Borrelia recurrentis: louse borne
Borrelia hermsii, turicatae, duttoni, crocidurae: tick borne

Question 16

What are the reservoir and method of transmission of tick and louse respectively?

Answer 16

Tick: squirrels or small rodents, tick saliva/feces

Louse: human to human transmission. No known animal reservoir, hemolymph/feces

Question 17

How do pathogenesis of B.hermsii work?

Answer 17

They change their surface proteins so that antibodies cannot recognize them but as the number of diff type of spirochetes are made, different antibodies corresponding to that spirochetes are also made so eventually the infection is cleared.

Question 18

Particular vsp alleles has been associated with ___

Answer 18

CNS localization

Question 19

What genes contribute to pathogenesis of B.hermsii

Answer 19

Vlp and vsp genes that are on a linear plasmid

Question 20

Borrelia hermsii are very invasive in humans and what do they infect?

Answer 20

Borrelia hermsii invades blood stream

Many tissues and organ systems,including central nervous system

Question 21

How do we diagnose &treat B.hermsii?

Answer 21

PCR,

Penicillins,tetracyclines

Question 22

What disease does Borrelia burgdorferi cause?

Answer 22

Lyme disease

Question 23

What kind of surface proteins are in high heterogeneity in B.burgdorferi?

Answer 23

OspA, OspB, OspC

Question 24

What are B.burgdorferi’s habitat?

Answer 24

Small rodents, and they are transmitted to humans by tick bites

Question 25

How does lyme disease get transmitted?

Answer 25

By regional ixodes tick species(hard ticks)

Question 26

How does lyme disease get transmitted ?

Answer 26

By bite of nymph, infected ticks

Tick saliva injected into skin

Question 27

Explain pathogenesis of lyme disease

Answer 27

Organism is very invasive, and reaches blood stream and dissseminates to many organs including CNS

Question 28

What are the critical symptoms of lyme disease?

Answer 28

Erythema chronium migrnas(rashes) ans secondary lesions

Neurologic and cardiac abnormalities( headache, stiff neck, conjunctivitis, muscle pain,

Arthritis((swelling of joints) —> chronic

Question 29

How do we diagnose lyme disease?

Answer 29

Physical exam for Ecm lesion or tick bites

Biopsy: id of organism by culture

PCR

Question 30

How do we treat lyme diseae?

Answer 30

Penicillin, ceftriaxone, tetracyclines

Question 31

What is the bacteria that live in the free living water or urban slum?

Answer 31

Leptospirosis

Question 32

What is leptospirosis reservoir?

Answer 32

Animal reservoir!(domestic and wild animals)

Question 33

How do leptospirosis transmit disease?

Answer 33

-Source of infection: water contaminated with infected urine of carried animals
-entry to skin

Question 34

Explain leptospirosis pathogenesis?

Answer 34

Invasive!

Infect multiple organs including CMS

Question 35

What is the outcome of leptospiral infection

Answer 35

Top: complex, multi system disease (aseptic meningitis, renal failure, jaundice, myocarditis, pulmonary hemorrhage, refractory shock

Middle: undifferentiated fever

Bottom: inapparent infection

Question 36

What are the clinal courses of leptospirosis?

Answer 36

Sudden fever, headache,bacteia present in blood

Question 37

How do we diagnose leptospirosis?

Answer 37

PCR, Serology

Penicillin,doxycycline, erythromycin

Low mortality rate

Question 38

Is spirochete gram negative

Answer 38

Yes