Treponema pallidum, borrelia and leptospira interrogans

Question 1

Give the four subspecies of Treponema pallidum

Answer 1

Treponema pallidum
Treponema pertenue
Treponema endemicum
Treponema carateum

Question 2

What disease does Treponema pallidum cause?

Answer 2

Syphilis (worldwide)

Question 3

What disease does Treponema pertenue cause?

Answer 3

Yaws

Question 4

What disease does Treponema endemicum cause?

Answer 4

Endemic syphilis (Middle East and Central and South Africa)

Question 5

What disease does Treponema carateum cause?

Answer 5

Pinta

Question 6

What is the shape of Treponema spp?

Answer 6

Helically coiled, corkscrew shaped cells with 8-12 regular spirals

Question 7

Are Treponema encapsulated?

Answer 7

No

Question 8

Is Treponema motile?

Answer 8

Yes

Question 9

Can Treponema form spores?

Answer 9

No

Question 10

What can Treponema form instead of spores in the body

Answer 10

Cysts

Question 11

How are Treponema different from other motile bacteria?

Answer 11

Endoflagella

Question 12

Is Treponema gram positive or neegative?

Answer 12

It is gram negative

Question 13

Is Treponema pallidum aerobic or anaerobic

Answer 13

Strict anaerobe

Question 14

What staining method can be used to reveal Treponema from smears?

Answer 14

Silver impregnation methods

Question 15

How can live Treponema be visualised?

Answer 15

Dark field microscopy

Question 16

How difficult is it to culture Treponema pallidum?

Answer 16

It is fastidious, requiring very narrow pH and temperature ranges. It has not been successfully cultured in vitro

Question 17

Describe the resistance of Treponema pallidum

Answer 17

It can not survive a long time in the environment. It is rapidly inactivated by mild heat, cold,
desiccation, and most disinfectants.
It is inactivated by contact with oxygen, distilled water, soap
T.pallidum is sensitive to arsenicals, mercurials, bismuth, common antiseptic agents and
antibiotics (penicillines).

Question 18

How is Treponema pallidum transmitted?

Answer 18

Through sexual contact (venereal disease);
Through placenta (congenital syphilis);
Rarely with direct contact and with infected blood during transfusion

Question 19

How long is the incubation period for syphilis?

Answer 19

Incubation period is about a month (10 - 90 days)

Question 20

Give 4 stages in the clinical manifestation of infection with Treponema Pallidum

Answer 20

Primary syphilis
Secondary syphilis
Latent syphilis
Tertiary syphilis

Question 21

How does primary syphilis begin?

Answer 21

The organisms penetrate mucous membranes or enter through the very tiny cuts on the skin.
Treponema multiplies in the site of entry causing formation of the primary specific lesion, named
“hard chancre”.

Question 22

Describe the chancre of primary syphilis

Answer 22

Chancre is painless, circumscribed, indurated, superficially ulcerated lesion

Question 23

What is the next stage of primary syphilis after formation of a chancre?

Answer 23

Treponema disseminates away from the site of initial entry to regional lymph nodes and
provokes their specific inflammation (syphilitic buboes).

Question 24

Describe the changes in regional lymph nodes in primary syphilis

Answer 24

Lymph nodes are swollen, discrete,

indurated, and rubbery.

Question 25

What is the normal progression of a chancre over time in primary syphilis?

Answer 25

The chancre heals spontaneously (!) in 10-40 days, leaving a thin scar

Question 26

Roughly how long does primary syphilis last?

Answer 26

3 months

Question 27

When does secondary syphilis set in?

Answer 27

3 months after primary syphilis

Question 28

What causes the secondary lesions in syphilis?

Answer 28

The secondary lesions are due to dissemination through | the blood and wide-spread multiplication of the spirochetes.

Question 29

How may secondary syphilis present?

Answer 29

``` It may appear with: ROSEOLAR RASHES PAPULAR RASHES MUCOUS PATCHES (broad, flat, erosive lesion of secondary syphilis that occurs on moist skin or mucous membranes and is often marked by a yellowish discharge) CONDYLOMATA (anogenital warts). ```

Question 30

In which stage of syphilis are patients most infective?

Answer 30

The secondary stage as the spirochetes are present abundantly in the lesions

Question 31

What is the natural progression of secondary syphilis?

Answer 31

Lasts 2-3 years Lesions heal spontaneously (!) but during first 4-5 years there may be relapses of rashes

Question 32

How is latent syphilis diagnosed?

Answer 32

Serological tests

Question 33

When does tertiary syphilis present?

Answer 33

Years to decades after secondary syphilis

Question 34

How does tertiary syphilis present?

Answer 34

After several years tertiary syphilis appears with cardiovascular lesions (aneurysms), chronic gummata and neurological manifestation (tabes dorsalis or dementia)

Question 35

What are gummas?

Answer 35

Highly destructive lesions (necrotizing granulomas ) that usually occur in skin and bones but may also occur in other tissues. Gumma includes few treponemes

Question 36

How well does the immune system deal with Treponema pallidum?

Answer 36

Immunity is weak, non-sterile, and cell-mediated. Antibodies which are formed during infection are not protective

Question 37

What is the significance of the antibodies produced during infection by Treponema pallidum?

Answer 37

Diagnostic significance

Question 38

Can a person be reinfected with Treponema pallidum?

Answer 38

Yes (superinfection)

Question 39

What is different about getting infected by Treponema pallidum a second time?

Answer 39

Due to 'chancre immunity' there are no primary signs

Question 40

What is the usual therapy of syphilis?

Answer 40

Prolonged penicillin preparations

Question 41

How can syphilis be diagnosed in a lab during the primary and secondary stages?

Answer 41

Microscopy with dark field microscopy of native smears or fluorescent antibody (immunofluorescence) test

Question 42

Can syphilis be diagnosed using serology?

Answer 42

Yes, 2-3 weeks after chancre appearance

Question 43

What group of borrelia species cause Lyme's disease?

Answer 43

B.burgdorferi

Question 44

How can the size of Borrelia be described?

Answer 44

Large

Question 45

Are Borrelia motile?

Answer 45

Yes

Question 46

Describe the shape of Borrelia

Answer 46

3-8 wide, open coils

Question 47

Are Borrelia gram positive or negative?

Answer 47

Negative

Question 48

Are Borrelia aerobes or anaerobes?

Answer 48

Microaerobic - need oxygen but in lower concentration than atmosphere

Question 49

Can Borrelia be cultivateed?

Answer 49

Not into media but possible in chicken embryo or in rodents

Question 50

What diseases are Borrelia species primarily responsible for?

Answer 50

Relapsing fevers and Lyme's disease

Question 51

How is Borrelia transmitted to humans?

Answer 51

Lice or ticks

Question 52

What species of Borrelia is responsible for the louse-borne/epidemic type of relapsing fever?

Answer 52

Borrelia recurrentis

Question 53

What is the reservoir host for Borrelia recurrentis?

Answer 53

Humans

Question 54

What is the reservoir for Borrelia species which cause the tick borne/endemic type of fever?

Answer 54

Rodents

Question 55

What is the vector for Borrelia bungdorferi?

Answer 55

Ticks

Question 56

What are the main reservoirs for Borrelia bungdorferi?

Answer 56

Rodents and deer

Question 57

What does Borrelia responsible for relapsing fever do once it has entered the body?

Answer 57

Enters the bloodstream and multiplies in the organs

Question 58

What is the body's response to the presence of Borrelia recurrentis?

Answer 58

Mounting an immune response including a fever, lasting 3-5 days which destroys the bacteria in the blood

Question 59

Why does the fever relapse after an immune response destroys Borrelia recurrentis in the blood?

Answer 59

The pathogen has he ability to undergo multiple cyclic antigen variations so that once one strain is eliminated, another comes to dominate and infect the blood, triggering another immune response with new antibodies.

Question 60

How long is the afibrile period usually in relapsing fever?

Answer 60

4-10 days

Question 61

How can Borrelia recurrentis be diagnosed in a lab?

Answer 61

Microscopy of stained blood smears

Question 62

How can epidemic and endemic Borrelia strains be distinguished?

Answer 62

Injection into guinea pigs which are highly sensitive to animal Borrelia and less sensitive to human Borrelia

Question 63

What is the incubation period for Lyme's disease?

Answer 63

3-30 days

Question 64

What are the 3 stages of Lyme's disease?

Answer 64

1. Localised infection 2. Disseminated infection 3. Persistent infection

Question 65

What happens during the localised infection stage of Lyme's disease?

Answer 65

There appears an expanding annular skin lesion (erythema migrans).

Question 66

What happens during the disseminated infection stage of Lyme's disease?

Answer 66

Fever Myalgia Arthralgia Lymphadenopathy.

Question 67

When do the symptoms of the persistent infection stage of Lyme's disease arise?

Answer 67

Arises in months or years after the disseminated stage

Question 68

What happens during the localised infection stage of Lyme's disease?

Answer 68

Chronic arthritis Polyneuropathy Acrodermatitis Encephalopathy

Question 69

How can laboratory diagnosis of Borrelia burgdorferi be done?

Answer 69

Serology | Microscopy in the site of entry during the first stage

Question 70

What are the prophylactic methods that should be used to avoid Borrelia infections?

Answer 70

Avoid the vectors Cover skin with clothing in tick habitats Use tick repellent in tick habitats Periodic skin inspection and tick removal Avoid endemic areas

Question 71

What is the treatment for Borrelia?

Answer 71

Borrelia are sensitive to penicillins, tetracyclines, newer macrolides and cephalosporins.

Question 72

Describe the shape of Leptospira interrogans

Answer 72

Slender Tightly coiled Flexible Hooked ends that create an S or C shape

Question 73

Is Leptospira interrogans encapsulated?

Answer 73

No

Question 74

Is Leptospira interrogans motile?

Answer 74

Yes

Question 75

Is Leptospira interrogans spore forming?

Answer 75

No

Question 76

Is Leptospira interrogans Gram positive or negative?

Answer 76

Negative

Question 77

How can Leptospira interrogans be visualised?

Answer 77

Dark field microscopy | Visualisation in tissue by silver impregnation methods

Question 78

Can Leptospira interrogans be easily cultured?

Answer 78

Yes they are far from fastidious

Question 79

Is Leptospira interrogans sensitive to heat?

Answer 79

Yes

Question 80

Is Leptospira interrogans sensitive to acid?

Answer 80

Yes, killed by stomach acid in 30mins

Question 81

Is it easy to kill Leptospira interrogans with disinfectants?

Answer 81

Yes

Question 82

How is the survivability of Leptospira interrogans in water?

Answer 82

L.interrogans can survive into clean water for some days and can multiply in the environmental water at summer.

Question 83

How long can soil remain infective if it is contaminated with urine containing Leptospira interrogans

Answer 83

Urine-contaminated soil can remain infective for as long as 14 days.

Question 84

What are the main reservoirs of Leptospira interrogans?

Answer 84

Rodents Domestic animals A range of hosts worldwide

Question 85

How is Leptospira interrogans transmitted?

Answer 85

Direct or indirect contact with urine containing virulent leptospires. Leptospires from urine-contaminated environments, such as water and soil, enter the host through the mucous membranes and through small breaks in the skin.

Question 86

How long is the incubation period of Leptospira interrogans?

Answer 86

About 10 days (3-25)

Question 87

Where does Leptospira interrogans go after entering the body?

Answer 87

Through the blood it reaches the organs, most commonly the CNS, kidneys and liver

Question 88

What are the symptoms during onset of infection with Leptospira interrogans?

Answer 88

``` Abrupt fever Severe headache Muscle pain Nausea Jaundice in severe cases ```

Question 89

How long does the initial phase of leptospira interrogans infection last?

Answer 89

7 days

Question 90

What takes place after the initial phase of infection by Leptospira interrogans?

Answer 90

Leptospires are rapidly eliminated from all host tissues except the brain, eyes, and kidneys.

Question 91

What is the most notable feature of severe leptospirosis?

Answer 91

Progressive impairment of hepatic and | renal function

Question 92

How is the immunity after leptospirosis?

Answer 92

It is primarily humoral (antibody - mediated) Type-specific Long-lasting (may persist for years). Cell-mediated immunity is not protective. Due to a lot of serotypes immunity in general is weak

Question 93

Can microscopy be used to diagnose leptospirosis?

Answer 93

Yes

Question 94

Where can samples be taken from for microscopy of Leptospirosis interrogans?

Answer 94

Blood (first 8-10 days) Urine (from second week) CSF

Question 95

Is culture used to diagnose leptospirosis?

Answer 95

No, too slow

Question 96

is serology used to diagnose leptospirosis?

Answer 96

Yes