Spiral bacteria

Question 1

Describe the morphology and staining of spirochaetes.

Answer 1

Gram negative

Corkscrew shape with axial flagella, and an outer sheath

Question 2

Describe the cell wall of spirochaetes.

Answer 2

Gram negative (but don’t stain well) and FLEXIBLE cell wall

Question 3

What is the causative agent of syphilis?

Answer 3

Treponema pallidum (spp. pallidum)

Question 4

What is a non-venereal disease from the treponema genera?

Answer 4

Yaws = chronic, relapsing non-venereal disease
Bejel = acute non-venereal syphilis

Question 5

What are different, older names, for syphilis?

Answer 5

The great imitator - many presentations

Great pox

Question 6

What was a tragic study for syphilis?

Answer 6

Tuskegee study

Question 7

Treponema pallidum:
Causes what?
Stages?

Answer 7

causes syphilis

Three stages - primary, secondary, tertiary

Question 8

What is the 1/3rd rule?

Answer 8

one third self cure
one third keep relapsing with secondary syphilis
1/3rd go on to tertiary syphilis

Question 9

What is primary syphilis?

Answer 9

Painless ulcer (chancre) at the site of initial incoluation
Chanchre goes away after 3 weeks.

Question 10

What is secondary syphilis?

Answer 10

maculopapular eruptions including PALMS AND SOLES

+ condylomata lata

Question 11

What is condylomata lata?

Answer 11

Flat warts of syphilis

Question 12

What is tertiary syphilis?

Answer 12

Get endarteritis obliterans –> gummata

Question 13

What is endarteritis obliterans?

Answer 13

last of terminal blood vessels gets obliterated resulting in a lesion called a gumma (plural is gummata) - this happens years later

Question 14

How does one get the classic syphilitic shuffle?

Answer 14

Gummata in dorsal columns of spinal cord - lose feeling in legs causing shuffling

Question 15

What is Charcot’s joint?

Answer 15

When the spinal cord is affected by syphilis, lose proprioception and percetion of feet - causes lots of pressure and deprives blood to lower extremities causing scarring - when it happens to the knee = Charcot’s joint

Question 16

What causes Hutchinson’s teeth?

Answer 16

Syphilis in utero

Question 17

Non-sexually transmitted treponemal disease endemic of North Africa.

Answer 17

Bejel

Question 18

What is used to diagnose syphilis?

Answer 18

Darkfield microscopy or DFA microscopy of chancre fluid - primary
2ndary - serology

Question 19

What do we now do for screening for syphilis and confirming the diagnosis?

Answer 19

Do the treponemal test for the screen

Do the non-treponemal test for confirmation

Question 20

When is a lung puncture done for diagnosis of syphilis?

Answer 20

Done unless the person is over 40 with a normal neurologic exam

Question 21

What is the Argile robinson pupil?

Answer 21

Shine light into someone with advanced syphilis and their pupil will not contract - but, will accomodate

Question 22

What is unusual genetically of Borrelia?

Answer 22

Linear chromosome

Question 23

Describe Borrelia in terms of motility, morphology.

Answer 23

Spirocheate

Flagella beneath outer membrane

Question 24

Borrelia burgodorferi causes what disease?

Answer 24

Lyme

Question 25

What tick transmits lyme disease?

Answer 25

Deer tick

Question 26

How many stages does lyme disease have?

Answer 26

3

Question 27

What is the first stage of lyme disease?

Answer 27

3d-4 weeks - erythema migrans and flu-like symptoms

Question 28

What is the second stage of lyme?

Answer 28

weeks-months

- arthritis, sometimes meningitis and Bell’s palsy

Question 29

What is the third stage of lyme?

Answer 29

months-years - chronic arthritis and progressive CNS disease

Question 30

Why do people think there is such thing as chronic lyme disease?

Answer 30

Since the damage persists

Question 31

What does erythema migrans look like?

Answer 31

Bullseye

Question 32

How is lyme disease diagnosed?

Answer 32

Bullseye (erythema migrans) + visiting risky area

ELISA, Western, PCR - for acute facial palsy, arthritis if no Erythema migrans

Question 33

What is useless int eh first 4 weeks and useless as a test of cure for lyme?

Answer 33

Serodiagnostic tests

Question 34

What serodiagnosis for lyme is done first?
What is done to confirm?
What is prone to false positives?

Answer 34

EIA or IFA first
confirm positives with Western blot IgM and IgG
IgM prone to false positives (esp. late in disease)

Question 35

What is done if someone has a lyme tick bite?

Answer 35

single dose of doxycycline

Question 36

What causes leptospirosis?

Answer 36

Leptospira

Question 37

Leptospira has a worldwide distribution and can be either free living or assocaited with what?

Answer 37

rats and raccoons

Question 38

Infection by leptospira is usually due to what?

Answer 38

direct or indirect exposure to animal urine

Question 39

What is the primary lesion of leptospirosis due to?

Answer 39

disruption of cell membranes of small blood vessels throughout the body

Question 40

What toxin does leptospira have?

Answer 40

Glycoprotein toxin

Question 41

What does leptospirosis cause?

Answer 41

Widespread capillary leakage and petechial hemorrhage

Question 42

What many phases does leptospiroris have?

Answer 42

2

Question 43

What is first stage leptospirosis?

Answer 43

1-2 weeks - fever and malaise - decreases or disappears after one week

Question 44

What is second phase leptospirosis?

Answer 44

aseptic meningitis, hepatitis, neprhitis, conjunctivitiis with increased IgM titre

Question 45

How is leptospirosis diagnosed?

Answer 45

Serology + urine or blood cultures