Spirochetes and Misc Bacteria

Slackers Facts by Mike Ori

Disclaimer

The information represents my understanding only so errors and omissions are probably rampant. It has not been vetted or reviewed by faculty. The source is our class notes.

The document can mostly be used forward and backward. I tried to mark questionable stuff with (?).

If you want it to look pretty, steal some crayons and go to town.

Finally…

If you’re a gunner, buck up and do your own work.

Describe the morphology and size of a spirochete

Spirochetes are long but very narrow spiral shaped bacterial with internal flagella that

course down the side of the bacterium essentially between the inner and outer

membrane,

Name the spirochete visualization technique

Usually best visualized with dark-field microscopy. Antibody staining can also be

used.

Name three medically important spirochete species

TreponemaLeptospira

Borrelia

What disease is associated with treponema

Syphilis

What diseases are associated with Borrelia

Recurring feversLyme disease

What disease is associated with Leptospira

Leptospirosis

Name the stages of syphilis

PrimarySecondary

(Latent)Tertiary

Primary syphilis time frame

3 week incubation

Primary syphilis sx

Chancre at site of infection

Secondary syphilis time frame

Develops 2-8 weeks after chancre formation. Lasts days to weeks.

Secondary syphilis sx

Macular papular rash over body surface including soles and palms.

Latent syphilis sx

Essentially none. Low infectivity.May revert to secondary syphilis with high

infectivity.

Tertiary syphilis time frame

Typically develops in 15-20 years

Tertiary syphilis affected systems

NeurosyphilisCardiavascular syphilis

Neurosyphilis sx

Chronic meningitisBrain degeneration

Psychosis

Cardiavascular syphilis sx

Ascending and transverse aortic dilation due to endarteritis of the vasa vasorum

Congenital syphilis timeframe

Active infection after the 4th month

Congenital syphilis sx

Macular papular rash similar to secondary syphilis in adults

Bone changes (saddle nose, saber shins)

Anemia, thrombocytopenia, liver failure

Syphilis tests

VDRL – non-treponemalFluorescent treponemal antibody (FTA)

Describe VDRL sensitivity and specificity

Sensitive but not specific as a number of other situations can increase cardiolipin antibody

levels that form the basis of the test. Always confirm positive results.

Syphilis rule of thirds

1/3 secondary1/3 latent

1/3 chronic (~3% of original?)

Borrelia staining

Stains well with Geimsa or Wright stains

Borrelia recurrentis and hermsii disease characteristics

Up to four cycles of fever that are separated by a few days and that each last about a week.

Borrelia relapse basis

Limited antigenic variation allows immune escape

Relapsing fever vectors

Ticks and lice

Relapsing fever severity

Tick borne fatality rareLouse borne fatality more common

General lice infection mechanism

Infected lice are crushed and then their introduced into a superficial wound.

Lice must move between hosts.

Etiologic agent: Bulls eye rash, arthritis, myalgia, myocarditis, meningoencephalitis

Borrelia burgdorferi

Borrelia burgdorferi cause disease common name

Lyme disease

Lyme disease lifecycle

Ixodes ticks feed on small animals and deer. Humans are incidental hosts.

Lyme disease time course

Erythema migrans (bulls eye rash) within first month

Secondary progression to debilitating arthritis, cardiovascular disease, and nervous system

involvement that can develop immediately or that may be delayed for years.

Lyme disease epidemiology

Outdoor people in the mid-atlantic and new england states

Leptospirosis vector

Rodents, cattle, dogs urine contaminated water

Leptospirosis sx

Flu-like with meningitis

Etiology: Large inflamed inguinal or axillary lymph node that is very painful that occurs

after a visit to the four corners area

Yersinia pestis

Describe pneumonic plaque

Pneumonic involvement of Y. pestis that causes necrotizing hemorrhagic pneumonia with a

fatality > 90%

Describe the potential for person to person spread of Y. pestis

Pneumonic involvement is highly contagious.

Yersinia pestis virulence factors

F1 capsular antigen expressed at 37CV and W antigens are antiphagocyticIntracellular survival in macrophage

Outer membrane proteins

Tularemia sx

Similar to plague

Brucella sx

Recurrent bacteremia with fever.Infects reticuloendothelial system

Brucellosis epidemiology

Occupational contact with infected animals (farmers, vets, kinky fetishers)

Unpasteurized dairy products