Spirochetes Flashcards
What is the Gram stain of spirochetes and do they have LPS? Flagella?
- Gram negative - do not have LPS, periplasmic flagella
What is the method for viewing spirochetes
-Dark-field microscopy
What are the 3 genera that are pathogenic to humans?
- Treponema, Borrelia, and leptospira
What Treponeme causes endemic syphilis (bejel)? What causes yaws?
- T. pallidum endemicum
- T. pallidum pertenue
What actually causes the tissue destruction in syphilis?
What is the only source its transmitted from?
- our immune response
- From humans only via sex, blood contact, or congenital
Can syphilis spread by fomites?
What are the 3 phases of syphilis?
- No
- 1 - painless chancre
2- Rash everywhere “copper colored rash”; “nickle and dime rash”
3- Neurosyphilis - tabes dorsalis
What can also occur in secondary and tertiary syphilis?
- 2: patchy alopecia “moth eaten”
- 3: gummas (granulomas), aneurysm and aortic endocarditis
What do you see in early congenital syphilis vs late congenital syphilis?
- early: possible still birth, snuffles - highly infectious
- late: deafness, Hutchinson teeth, saber shins (curvature of long bones), saddle nose
If syphilis is suspected what is the initial test to be done?
- Nontreponemal tests: measures IgG and IgM. Done because they are rapid- VDRL and RPR. Can get false positives
What is confirmation of the non-treponemal test?
What is a problem with tests for syphilis?
- Treponemal tests: FTA-ABS, TP-PA, EIA
- Patients become positive in late first phase of syphilis.
Where are Bejel found and what is there presentation?
Where are Yaws found and what is there presentation?
- Bejel found in A’s (Africa, Asia, Austraila) classically gummas of skin spread by contaminated eating utensils
- S. america, africa, asia presents with “cauliflower lesions” - direct contact
Where is Pinta found and what is its presentation?
- Found in south and central america and presents with small pruitic papules on skin.
What is the #1 vector born disease in the US?
- Borrelia burgdorferi - Lyme disease
What is Borrelia burgdorferi transmitted by?
What is the first stage of lyme disease characteristic of?
- black-legged tick in the NE US
- Bull’s eye rash” - appears 3-30 days after bite
What is characteristic of stage 2 lyme disease?
What is characteristic of stage 3 lyme disease?
- intermittent arthritis
- prolonged arthritis, encephalitis, fibromyalgia
What would you do for diagnosis?
To be absolute one of the 2 criteria must be met?
- Ab titer (increase in IgM or IgG) followed by western blot for proteins
- (1) Erythema migrans (2) at least 1 late manifestation and positive lab confirmation
What if somebody got something in a rustic log cabin in colorado?
What are the symptoms of relapsing fever?
- Relapsing fever - transmitted by B. hermsi; could be tick or louse borne (more severe though more rare).
- fluctuating fever/chills then drenching sweats
When are organisms present in the relapsing fever patient?
What is diagnostic for relapsing fever?
- during the febrile period; then antibodies kill them during the afebrile period
- Dark-field microscopy of blood smears during febrile period, patients have a positive VDRL
- What is obtained in Hawaii, transmitted through mouse urine, and contracted after swimming?
- First phase of this disease is a flu-like illness, what are the symptoms of the second phase?
- Leptospirosis from Leptospira interrogans.
- Sudden onset of headache, myalgia, chills, abdominal pain, and conjunctival suffusion. Can lead to Weil disease - renal failure, hepatic symptoms with jaundice.
What is diagnostic for Leptospirosis?
- Dark-field microscopy (not reliable), serology most commonly used (MAT)
