SPIROCHETES Flashcards
Motile, long, slender, helically curved, gram-negative bacilli
SPIROCHETES
They have an unusual morphologic feature of axial fibrils and outer sheath
Fibrils/axial filaments – flagellalike organelles that wrap around
the bacteria‘s cell wa
flagella-like organelles that wrap around
the bacteria‘s cell wall
Fibrils/axial filaments
Enclosed within the
outer sheath, and
facilitate motility
(corkscrew-like winding)
of the organism
SPIROCHETES
platelike
structures where fibrils are
attached, located near the ends
of the cell
insertion disk
derived from the Greek owed meaning “turning thread”
TREPONEMA
it has 6 – 10 axial filaments and 1 insertion disk
TREPONEMA
how many axial filaments and insertion disk does treponema have?
6 – 10 axial filaments and 1 insertion disk
infect only humans and have not been cultivated for more than one passage in vitro
Treponema
they are killed rapidly at 42C and are used as a basis for syphilis therapy
- they remain visible in whole blood or plasma for at least 24 hours, which is of potential
importance in blood transfusion
Treponema
2 types of Antibodies of Treponema
Treponemal Antibodies
Non-treponemal (reagin) antibodies
Most species of treponema stain poorly in?
Gram’s Stain and Giemsa’s Method
Treponema is best observed with the use of?
Dark-field or phase-contrast microscopy
Etiologic agent of syphilis
Treponema pallidum subsp. pallidum
Fine spiral organism with 3 periplasmic flagella
Treponema pallidum subsp. pallidum
Appears white against a dark background
- Microaerophilic and survives longer in the presence of 3-5% oxygen
Treponema pallidum subsp. pallidum
This organism enters the host by either penetrating intact mucous membrane or entering
through breaks in the skin
o Not highly contagious
Treponema pallidum subsp. pallidum
Has a remarkable tropism (attraction) to arterioles – infection leads to endarteritis
Treponema pallidum subsp. pallidum
They die rapidly on drying and susceptible to disinfectants
- Generation time: 30 hours
Treponema pallidum subsp. pallidum
French disease/ Italian disease/ the great pox
Also known as the “great imitator” because it can copy and assume many clinical
manifestations
Syphilis
A disease of blood vessels and of the perivascular areas
It can cross the placenta
It is transmitted by direct/sexual contact or congenital
Syphilis
It is characterized by chancre, fever, sore throat, headache and rash (palms and
soles), gummas in skin, neurosyphilis
Syphilis
– a single erythematous, painless lesion that is non-tender and
firm with a clean surface and raised border
Chancre –
Stages of Syphilis:
Characterized by the appearance of a chancre (hunterial
chancre) usually at the site of inoculation, most commonly the
genitalia
o Within 3 – 6 weeks, the chancre heals
o Dissemination of the organism occurs during this stage
o This stage is highly contagious
Primary Syphilis
Stages of Syphilis:
o Starts when the organism reached a sufficient number, after 2 – 24 weeks
o Fever, weight loss, malaise, loss of appetite and skin rashes
o skin rash spreads from the palms and soles towards the trunk
Secondary syphilis
Stages of Syphilis:
condylomas develop at the anogenital region, axilla and mouth rash lasts 2 – 6 weeks
A period of latency follows lasting for several years
Secondary syphilis
The stage wherein the disease becomes subclinical but not
necessarily dormant
Diagnosis can be made only be serologic tests
Latent stage
Stages of Syphilis:
o It is the tissue destructive stage-highly disfiguring
o Appears 10 – 25 years after the initial infection
o Complications arise at this stage – central nervous system
disease, cardiovascular abnormalities, eye disease, granulomalike lesions (gummas)
Tertiary stage
Stages of Syphilis:
affects all parts of the body
cardiovascular and neuromuscular are most common
cause of death
Gummas- large granulomas resulting from hypersensitivity reactions
Tertiary stage
Stains used to detect treponema
Levaditti‘s Impregnation Stain and Fontana
Tribondeau
Non-treponemal flocculation tests:
Venereal Disease Research Laboratory (VDRL) test
Rapid plasma reagin (RPR) test
Automated Reagin test (ART)
Wasserman, Kolmer test
Treponemal tests:
FTA-ABS
MHA-TP
Treponema pallidum Hemagglutination (TPHA)
Treponema pallidum Immobilization (TPI)
Treponemal Test:
performed by overlaying whole treponemes
that are fixed to a slide with serum from patients suspected of having syphilis because of previous (+) VDRL or RPR test
FTA-ABS
Treponemal Test:
– utilize RBC from a turkey or other animal that
are coated with treponemal antigens
(+) formation of flat mat across the bottom of the
microdilution well
MHA-TP
Etiologic agent of Yaws/Frambesia Tropicana/ parangi/ paru/bua/bouba
- Traumatized skin comes in contact with an infected lesion
Treponema pallidum subsp. Pertenue
a nonvenereal infection, characterized by chronic ulcerative sores anywhere on the
body with eventual tissue and bone destruction leading to crippling if untreated
Yaws –
Lesions:
Mother of yaws/ frambesia
Primary Lesion
Lesions:
Daughter of yaws
Secondary lesion
Lesions:
Gangosa
Tertiary Lesions
Causative agent of pinta/carate/mal del pinto/azul
common in tropical America
Treponema carateum
Infection of the skin
o lesions heal slowly unlike syphilis and yaws
o Primary lesion is a slowly enlarging painless papule on the hands, scalp and feet with
regional lymph node enlargement followed in 1-12 months by a generalized red to slateblue macular rash
Pinta
Causative agent of endemic non-venereal syphilis/bejel
Treponema pallidum subsp. Endemicum
transmitted by direct contact with active lesions and contaminated fingers
Bejel
Blood spirochetes
BORRELIA
Composed of 3 – 10 loose coils and are actively motile
BORRELIA
Stains well with Giemsa stain; slow growing spirochetes.
- Species that have grown in vitro are microaerophilic
BORRELIA
Has 30-40 axial filaments and 2 insertion disks.
BORRELIA
Agent of louseborne or Epidemic relapsing fever/ European relapsing fever
Borrrelia Recurrentis
Transmitted by Pediculus humanus (louse)
Borrrelia Recurrentis
Humans are the only reservoir.
Borrrelia Recurrentis
Agents of tickborne relapsing fever/ Endemic or American Relapsing feve
Borrelia hersmii/ B. turicatae/ B. dutoni / B. Parkeri
Transmitted via tick bites – Ornithodoros (soft ticks)
Borrelia hersmii/ B. turicatae/ B. dutoni / B. Parkeri
Agents of Lyme disease
Borrelia burgdorferi (sensu stricto), B. garinii, B. afzelii
Transmitted by the bite of Ixodes ticks – Ixodes pacificus, Ixodes dammini (deer ticks), Ixodes
persulcatus
Deer and rodents (Peromyscus leucopus – white-footed mouse) – ticks‘ natural hosts
Borrelia burgdorferi (sensu stricto), B. garinii, B. afzelii
It is maintained in the environment by horizontal transmission from infected nymphal ticks.
Borrelia burgdorferi (sensu stricto), B. garinii, B. afzelii
An acute infectious disease marked by recurrent febrile episodes; it has 2-10 relapses.
- Fever, headache, myalgia 2-15 days after infection
Relapsing Fever
An acute, recurrent inflammatory infection involving the large joints like the knees, with local
inflammation and swelling.
- It was first observed and described in 1975 among people of Old Lyme. Connecticut, USA.
Lyme disease
3 stages of lyme disease:
characteristics red, ring-shaped lesion w/ a central clearing.
- appears at the site of the tick bite but may also develop at other sites.
- signs and symptoms: headache, fever, muscle, joint pain and malaise
First Stage – Erythema Migrans
microscopy can be used for detection in blood cultures after 2-3 weeks of incubation at
34-37C
Darkfield
For tissue section of Lyme disease what stain can be used?
Warthin-starry stain
For blood and CSF of Lyme disease, what stain can be used?
Acridine Orange and Giemsa Stain
important in diagnosis of B. burgdorferi DNA in urine.
Polymerase chain reaction
Culture media for Lyme Disease?
Keller’s medium or chick embryo
Lyme disease serodiagnosis
Immunofluoresence Assay (IFA), Enzyme-linked immunosorbent assay (ELISA), Western Blot
The standard method for diagnostic testing for Lyme Disease
Serology
Serodiagnosis for Relapsing FEver
Increased titers to Proteus OX K antigens (up to 1:80)
Tightly coiled, thin, flexible, obligate aerobic spirochete; spimming motility.
LEPTOSPIRA
Often seen as a chain of cocci (dark-field microscope)
LEPTOSPIRA
Have “question mark-like” shape.
LEPTOSPIRA
Organisms have books rather than tapering off.
- Live in the lumen of the renal tubules (shed info the urine).
- Can survive in neutral or slightly alkaline waters for months
- Can be grown in artificial media.
LEPTOSPIRA
Hamsters and guinea pigs are the animal of choice for cultivation
LEPTOSPIRA
A zoonotic disease in human caused by L. interrogans.
Leptospirosis/Infectious Jaundice
A pretibial rash has been associated with serovar autumnalis (ft. Bragg fever)
Leptospirosis/Infectious Jaundice
2 syndrome of leptospirosis:
Septicemic stage, high fever and severe headache (3-7 days) followed by the
immune stage.
Hallmark of immune stage is aseptic meningitis.
Anicteric Leptospirosis
2 Syndromes of leptospirosis:
Severe form of illness characterized by liver, kidney and or vascular dysfunction.
Death can occur in up to 10% of cases
Icteric Leptospirosis/ Well Syndrome
can be differentiated from pathogens by their ability to grow to 10C
and lower.
Saprophytes
standard procedure using living cells.
Microscopic Agglutination (MA) –