Spirochetes

Question 1

What are the etiological agents of Lyme disease and relapsing fever?

Answer 1

Borrelia species.

Question 2

What are the etiologiocal agents of Lyme disease?

Answer 2

Borrelia burgdoferi, Borrrelia garnii, and Borellia afzelii.

Question 3

Where is B. burgdoferi found and what is its vector?

Answer 3

Borellia burgdoferi is found the US and Europe. It is carried by hard shelled ticks (Ixodes spp).

Question 4

Where are B. garnii and B. afzellia found and what is their vector?

Answer 4

B. garnii/B.afzellia are fund in Europe and Asia. They are carried by soft shelled ticks (Ornithodoros spp).

Question 5

What are the etiological agents of relapsing fever?

Answer 5

B. recurrentis and B. hermsii (as well as others).

Question 6

What is B. recurrentis transmitted by?

Answer 6

B. recurrentis is transmitted by the human body louse.

Question 7

What are B. hermsii and others transmitted by?

Answer 7

They are transmitted by soft shelled ticks (Ornithodoros spp.).

Question 8

What is the most common vector borne disease in the US?

Answer 8

Lyme disease.

Question 9

What developmental stage of the Ixodes tick is B. burgdoferi transmitted by?

Answer 9

The nymph stage (unlike RMSF which is by the adult tick).

Question 10

What aspect of tick physiology does B. burgdoferi take advantage of?

Answer 10

The Ixodes tick releases many immunosuppressive factors in its saliva, which B. burgdoferi takes advantage of.

Question 11

Hoe many “stages” does Lyme disease occur in?

Answer 11

Three stages.

Question 12

What is the first stage of Lyme disease?

Answer 12

Early localized infection. It is characterized by bacteria spreading in the skin, causing an erythema migrans lesion at the site of the tick bite.

Question 13

What is the second stage of Lyme disease?

Answer 13

Early disseminated disease. Is associated with hematogenous spread and non-specific systemic symptoms that may progress to neurological deficits (facial palsy) or cardiac involvement (lyme carditis).

Question 14

What is the third stage of Lyme disease?

Answer 14

Late persistent. It develops months to years after initial infection. It is most closely associated with frank arthritis.

Question 15

What are the two forms of relapsing fever?

Answer 15

Epidemic louse borne (louse can cause epidemics in crowded situations just like with R. prowazekii i.e typhus) and endemic tick borne.

Question 16

What causes epidemic louse borne relapsing fever and where is it found?

Answer 16

B. recurrents. Is found in sub-Saharan Africa and can cause severe disease.

Question 17

What causes endemic tick borne relapsing fever?

Answer 17

B. hermsii and others. Are carried by soft shelled ticks (Ornithodoros).

Question 18

What is diagnostically different between relapsing fever and Lyme disease?

Answer 18

Borrelia can be seen in the blood in relapsing fever, but can’t be seen in Lyme disease.

Question 19

How is Lyme disease diagnosed?

Answer 19

Lyme disease is typically diagnosed by recognition of the characteristic clinical picture followed by serological confirmation.

Question 20

What is a potential complication when treating Borrelia infections?

Answer 20

Jorisch-Herxheimer reaction may occur.

Question 21

What is a Jorisch-Herxheimer reaction?

Answer 21

A worsening of Borrelia symptoms (rigors, hypotension, high fever) that may be seen early on when treating Borrelia illness. Is caused by the release of endotoxins from dead Borrelia.

Question 22

What are most pathogenic Treponema subspecies of?

Answer 22

T. pallidum.

Question 23

What is the 3rd most common STD in the US?

Answer 23

Syphilis (caused by Treponema pallidum).

Question 24

Among what population is syphilis on the rise?

Answer 24

Men who have sex with men (MSM).

Question 25

How many phases does syphilis have?

Answer 25

Three.

Question 26

What is primary syphilis characterized by?

Answer 26

A painless skin lesion (Chancre) that develops at the site of infection. A painless lymphadenopathy develops 1-2 weeks later . The chancre resolves spontaneously ~2 months later while the lymphadenopathy may persist.

Question 27

What is secondary syphilis characterized by?

Answer 27

Disseminated infection. Consists of flu-like syndrome and lymphadenopathy followed by prominent skin lesions over the body (highly infectious).

Question 28

What else may appear in secondary syphilis?

Answer 28

Condylomata lata, which are raised skin lesions that occur in moist skin folds. Erosions may develop in the mouth or other mucosal surfaces.

Question 29

What is the course of secondary syphilis?

Answer 29

Secondary syphilis resolves spontaneously within a few weeks and may become clinically inactive or progress to late phase disease.

Question 30

What is tertiary syphilis characterized by?

Answer 30

A serious chronic inflammatory condition that can occur years to decades later and causes severe tissue destruction.

Question 31

What can be found in tertiary syphilis?

Answer 31

Granulomatous lesions (Gummas) that can occur in bone, skin, and other organs.

Question 32

What is the nomenclature of tertiary syphilis based on?

Answer 32

The tissue of primary involvement (i.e neurosyphilis, Cardiovascular syphilis, ect).

Question 33

What is the diagnostic test for early syphilis?

Answer 33

Darkfield examination of lesion exudate (must be performed by an expert microscopist since the organisms do not survive transport).

Question 34

How is syphilis diagnosed in most patients?

Answer 34

A two step process of serologic tests.

Question 35

What is the first serologic test for syphilis?

Answer 35

A non-treponemal test used for screening (such as venereal disease reseawrch laboratory [VDRL]).

Question 36

What is the second serologic tests for syphilis?

Answer 36

A treponemal test for confirmation, such as fluorescent treponemal Antibody absorbed (FTA-ABS) tests.

Question 37

What is the treatment of choice for syphilis?

Answer 37

Penicillin G.

Question 38

Where is Leptospirosis found?

Answer 38

It is found world-wide and is transmitted through contaminated water and soil.

Question 39

What is a rare complication that can occur with Leptospirosis infection?

Answer 39

Weil’s disease, a severe form of leptospirosis that occurs in less than 1% of patients. Is characterized by the presence of icteric symptoms (jaundice, ect).