Spirochetes and Misc Bacteria Slackers Facts by Mike

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

Treponema Leptospira Borrelia

What disease is associated with treponema

Syphilis

What diseases are associated with Borrelia

Recurring fevers Lyme disease

What disease is associated with Leptospira

Leptospirosis

Name the stages of syphilis

Primary Secondary (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

Neurosyphilis Cardiavascular syphilis

Neurosyphilis sx

Chronic meningitis Brain degeneration Psychosis

Cardiavascular syphilis sx

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

Congenital syphilis timeframe

Active infection after the 4 th 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-treponemal Fluorescent 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 secondary 1/3 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 rare Louse 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.