Download presentation source

1
Spirochaetes
5/24/2017
2
Presentation Outline
Morphology
 Organisms
 Diseases

 Leptospirosis
 Lyme
disease
 Syphilis

Tests
5/24/2017
3
Spirochete Morphology

Gram negative cell wall
 often
too small to see by light microscopy
 special stains
Spiral morphology
 distinctive tight coils
 Motile

 Periplasmic
flagella
5/24/2017
4
Spiral
5/24/2017
5
Spiral bacterium
Spirillum volutans
5/24/2017
6
Spirochete
5/24/2017
7
Axial Filament
Between cell wall and
cytoplasmic membrane
 Attached at either end of cell
 Overlap in the centre

 constrict
at overlap
 pulls ends together
5/24/2017
8
Spirochetes:Features
Chemoorganotropic
 Range of oxygen requirements
 Life style

 Free
living
 host associated
5/24/2017
9
Spirochaete Motility
Click on image
5/24/2017
10
Spirochetes: genera
Borrelia (lyme disease)
 Brachyspira
 Cristispira
 Leptonema
 Leptospira (Leptospirosis)
 Serpulina
 Spirochaeta
 Treponema (Syphilis)

5/24/2017
11
Leptospirosis
5/24/2017
12
Leptospira biflexa
free living saprophyte in moist environments
 motile, flagella
 aerobic
 can be grown in 2 weeks

5/24/2017
13
Leptospirosis
Leptospira interrogans
 Zoonosis of wild & domestic animals

 acquired
from urine of infected animals
 Dogs, rodents

Portal of entry
 broken

skin or mucosa
Bacteremia
5/24/2017
14
L. interrogans
Carried by wild and domestic animals
 source of human infection
 Streams, rivers, moist soil
 contaminated by animal urine
 Person to person very rare.

5/24/2017
15
Occupational exposure
farmers, slaughter house
 workers, veterinarians.

5/24/2017
16
L. interrogans
mild flu like febrile illness
 Weil’s disease

 renal
and hepatic failure
 vasculitis
 meningitis
 myocarditis
 death
Penetrate all organs including CNS
 Enter through small cuts

5/24/2017
17
Leptospirosis
Febrile illness not clinically distinctive
 Acute phase

 Leptospiremic
phase
 incubation 7 -14 days
 fever, headache, muscle pain nausea

Immune phase
 found
in urine
 meningitis
5/24/2017
18
Borrelia
Relapsing Fevers
Lyme Disease
5/24/2017
19
Relapsing Fever
Borrelia recurrentis
 Tick borne Relapsing fever

 rodents
are reservoir
 soft shelled ticks

Louse borne Relapsing fever
 humans
are reservoir
 body louse
5/24/2017
20
Borrelia
Easily seen in blood smear
 Also confirmed by injecting mouse

 blood
stream teaming with Borrelia
5/24/2017
21
B.recurrentis
Tick borne relapsing fever is a zoonotic
 Clinical evolution: relapsing fever
 Serological tests not useful
 treatment
 tetracycline

5/24/2017
22
Lyme Disease
Lyme, Conneticut USA spring/fall
 Borrelia burgdorfii
 reservoir rodents, pets,
deer
 vector hard shelled ticks
 Bite: incubation 3-30 days

5/24/2017
23
Lyme Disease: Early Signs
Erythema chronicum migrans
 Erythematous skin lesion

 small
macule or papule - enlarges to 68 mm.
Malaise, severe fatigue, headache, fever,
chills,
 chronic neurologic, cardiac rheumatic
manifestations.

5/24/2017
24
Lyme Disease: Complications

1 month or more
 myalgia,

lymphadenopathy
Up to 2 years
 meningitis,
encephalitis, peripheral nerve
neuropathy.

Cardiac disfunction, myopericarditis.
5/24/2017
25
Lyme Disease: Serology
Immunofluorescence assay
 Enzyme-linked immunoabsorbent assay
(ELISA)
 False positives

 other
spirochaetes
 infectious mononucleosis
 autoimmune disease
5/24/2017
26
Lyme Disease:Treatment

tetracycline or penicillin
5/24/2017
27
Syphilis
5/24/2017
28
Stages of Syphilis
Primary
 Secondary
 Tertiary

5/24/2017
29
Primary syphilis
Chancre: painless blister at
the site of contact
Heals spontaneously even if
untreated
5/24/2017
30
Syphilitic lesions of vulva
5/24/2017
31
Secondary Syphilis
Lesions of secondary
syphilis are dispersed
over the body
 Lesions appear on the
cooler parts of the body

5/24/2017
32
Secondary syphilis
5/24/2017
33
Syphilitic lesion on the cooler
parts of the body
5/24/2017
34
Neuronal Syphilis

Treponemes have
invaded the nerve
and set up a
lesion
5/24/2017
35
Syphilic lesions on bones
5/24/2017
36
Cardio Syphilis
5/24/2017
37
Tests for Syphilis

Break down products
of infected cells
 cardiolipin
 VDRL, Wasserman
 Simple, well
documented
 cross reactive eg
TB
 presumtive test

Treponemal antigens
 more expensive
 more specific
 confirmatory test
5/24/2017
38
Performance Objectives
Key terms, concepts
short answers
5/24/2017
39
Key Terms
5/24/2017
40
Key Terms
5/24/2017
41
Key Organisms
5/24/2017
42
Key Concepts
5/24/2017
43
Epidemiology of ???
Disease/bacterial factors
 Transmission
 Who is at risk
 Geography/ season
 Incidence
 Modes of control

5/24/2017
44
Short Answers
Construct a table of the virulence factors
associated with ??? and the biological
activity of each
 Use a series of no more than four diagrams
to describe the mechanism of ??? activity
 Describe the clinical manifestions ???
 Construct a table listing the common ???
species and the associated human diseases.

5/24/2017
45
The End
5/24/2017
46
Icteric leptospirosis
first stage: 3-7 days - septicemic

10-30 days - immune
 Cultures positive: blood, then CSF, then
urine

5/24/2017
47
Icteric leptospirosis
Jaundice, hemorrhage, renal failure,
myocarditis
 Anicteric described
 Best in CSF, blood, and urine culture -- 1st
week
 Lab test -- slide agglutination
 Doxycycline - treatment
 Prevention: rodent control

5/24/2017
48
So What

Know importance


#1 communicable disease growing fast
Know how it is spread
 Sexual
intercourse
 skin-skin contact
Know the symptoms
 Syphilis can be identified and cured

5/24/2017