Spirochetes

Question 1

Leptospira interrogans: features

Answer 1

Spirochete, endoflagella, THIN, easy growth, ONLY use fatty acids

Question 2

Leptospira interrogans: clinical

Answer 2

• initial stage: bactermia ! vasculitis/edema/rash ! petechiae, bleeding
• bacteria eliminated everywhere but liver, kidney, CNS, eyes
• second stage: “Weil’s disease”; liver & kidneys ! jaundice and nitrogen retention from kidney medulla destruction
• bloodshot/oozing eyes
• RARE: meningitis
• TOXIC ORGAN FAILURE – nausea, vomiting, intense pain ! DAMPs

Question 3

Leptospira interrogans: carriers

Answer 3

• infected water (persisting for weeks)

- rat & dog urine

Question 4

Leptospira interrogans: virulence

Answer 4

• no toxin
• just LPS, PG
• pathogenesis from endothelial damage to capillaries
• intracellular growth possible
• more affect on highly perfused organs (liver/kidney)

Question 5

Leptospira interrogans: treatment

Answer 5

• doxycycline prophylaxis
• corticosteroids for kidney inflammation
• mactrolides or quinolones or others
• vaccinate dogs
• antibiotics limited used (since it is intracellular)

Question 6

Borrelia recurrentis or

hermsii (20 others): features

Answer 6

G-, long spirochete, 0.4um, NO LPS, VECTOR BASED

Question 7

Borrelia recurrentis or

hermsii (20 others): clinical

Answer 7

• Bacteremia (within 1 wk.), fever, intense headache, muscle pain
• 3-5 day duration
• RECUR in 5-10 days latency, going through 5-10 cycles – relapsing fever

Question 8

Borrelia recurrentis or

hermsii (20 others): carriers

Answer 8

• recurrentis = louse

- hermsii = soft bodied ticks

Question 9

Borrelia recurrentis or

hermsii (20 others): virulence

Answer 9

• Inflammatory lipoproteins (OspA, OspC) - antigenic variation of VMP protein antigen causes recurrence (AB selects for mutants)

Question 10

Borrelia recurrentis or

hermsii (20 others): treatment

Answer 10

• Avoid vectors (hygene, long pants)

- Doxycycline, penicillins, 3rd gen cephalosporins (for bad infection) - NOT effective vaccine (OspA)

Question 11

Treponema pallidum

(Syphilis): features

Answer 11

long, thin spirochete; GAG sheath; endoflagella; NO LPS; cardiolipin in membrane; antiphogocytic proteins; unculturable in lab (rabbit testes), microaerophile

Question 12

Treponema pallidum

(Syphilis): clinical

Answer 12

• the “great imitator”
• primary: chancres; lymph node swells, heals spont; orgs remain
• seconday: red maculopapular rash anywhere with condylmas in moist areas; heals but latent, BACTEREMIA cause
• tertiary: no orgs; immune response; gumma, bones, heart, liver, brain = neurosyphilis (at 2’ or 3’), SC = tabes dorsalis (Romberg’s test)
• may cross placenta
• congenital syphilis: Hutchinson’s triad (keratitis = blind, VIII nerve deaf, teeth), neural defects, bone deformation, saddlenose

Question 13

Treponema pallidum

(Syphilis): carriers

Answer 13

• STD; only humans

- not contagious after 5 yrs - mother tested for syphilis after every stillbirth

Question 14

Treponema pallidum

(Syphilis): virulence

Answer 14

• highly infectious (10 orgs!) - hyaluronidase (spread/invasion), rapid motility & FEW surface proteins (long latent)
• NO LPS

Question 15

Treponema pallidum

(Syphilis): treatment

Answer 15

• scrape chancres for orgs - notify sexual contacts
• PenG injections (one i.m. injection <1yr. or 3 injections for later disease)
  Two below are
  VDRL
  Indirect: Reagin (IgM+IgA) test
  (cardiolipin)
  Direct: FTA test (binds T.pallidum)