Leptospira Flashcards
Case #2
* Blood samples were collected for serology from all the
affected animals, and a diagnosis of leptospirosis was made.
The remaining pregnant cows were treated with penicillin
and streptomycin. No further cases occurred.
Genus: Leptospira
- ________, ______, gram- ________ spirochete, which usually have ______ at _____ or _____ ends (0.1 um X 10-20 um)
- Organism winds around an _____ filament
(___ flagella) embedded between _____
envelope and _______ & forms ~ ___ coils/cell.
- ______ aerobe and uses only ______-chain fatty acids as ___-source
Growth on artificial media requires supplementation with 5 to 10% serum or
albumin +B1, B12, purines. (___-______)
Grows better at 30°C
Extremely sensitive to heat, light and disinfectants
Long, spiral, negative, hooks, one, both, axial, 2, outer, cytoplasm, 18, Strict, long, C, 5-flurouracil
What bacterium is pictured below?
Leptospira
What bacterium is pictured below?
What laboratory technique is used to view these microbes?
Leptospira, Darkfield microscopy
Leptospira: Classification and Virulence
- _____ TAXONOMIC SYSTEMS:
1. One is based on _____ and _______ differences
- L. biflexa is ____-______ (____ serovars)
38 serogroups & 63 serovars
- L. interrogans is ________ (____ serovars)
23 serogroups & 212 serovars of L. interrogans (based on shared and specific
LPS antigens)
Example: Strain Ictero#1 is in serovar icterohemorrhagiae of the serogroup
icterohemorrhagiae
Serovars present in the U.S. and Canada include
* L. pomona, L. hardjo, L. canicola, L. icterohemorrhagiae L. grippotyphosa, L.
bratislava
TWO, virulence, antigenic non-pathogenic, all, pathogenic, all
Leptospira Classification
- The other system is based on _______ differences
- Molecular studies have separated each species into genomospecies
- Genetically, L. interrogans has been divided into ____ genomospecies
- L. biflexa has been divided into __ species.
genetic, 14, 6
Leptosira - Genetic classification
- ____ pathogenic species
alexanderi, alstonii, borgpetersenii, inadai, interrogans, fainei,
kirschneri, licerasiae, noguchi, santarosai, weilii, kmetyi, broomii, and
wolfii
* More than ____ serovars
- __ nonpathogenic species
biflexa, meyeri,, vanthielii, terpstrae, yanawgawae, and wolbachii
* More than ___ serovars
14, 260, 6, 60
Leptospira: Ecology and Epidemiology
Natural reservoir is _________ of ________ tubules
May live in ________ renal tubules for _____ to _____ to ____, particularly in _____.
Following excretion in urine, may
survive for extended periods in
fresh water, soil, and mud, but ______ _________, ___ pH, or conditions of __ humidity or temperature
Serovars vary in occurrence depending on region and host species
Though not host-specific, there is host _______
lumen, nephritic, proximal, weeks, years, life, rodents
NOT saltwater, low, low, preference
Common serovars in animal disease
L. kennewicki – horses
L. bratislava – horses
L. pomona – pigs, cattle, horses, skunks
L. canicola – dogs, pigs
L. icterohaemorrhagiae – dogs, cattle, pigs, rats
L. hardjo – cattle
L. grippotyphosa – dogs, wildlife (racoons, skunks)
Leptospira - Virulence
Is _____ well understood, but ______ have shed light.
List the virulence factors:
Not, mutants
LPS (but at least 10-fold less toxic than E. coli)
Catalase (mutant confirmed)
Motility (axial filament; mutant confirmed)
Sphingomyelinase (hemolysin?)
Cytotoxins (protein and glycoprotein)
Ability to invade cells
LMSCCA
Leptospira - Diseases
- Most ___________ susceptible
1. List the diseases caused by leptospira infection:
2. Dogs tend to develop ?
3. Cats ?
vertebrates
- Premature birth, Abortion, Infertility, Jaundice, Agalactia, Hemoglobinuria
- acute hemorrhagic or chronic icteric and uremic syndromes
- rarely get clinical disease
HIAAJP
Leptospirosis:
Clinical symptoms of Disease
General signs include: ______, _____________, _______
Cattle (acute/subacute) L. pomona
Production: abnormal milk / agalactia
Clinical: rash, intense muscle pain, gastrointestinal signs, photophobia, encephalitis, acute nephritis, hemoglobinuria
Laboratory changes: hemoglobinuria, increased _____ (?)
Chronic disease in cattle and swine: L. pomona
abortion, stillbirth, or weak calves (L. hardjo)
Nephritis, uveitis, encephalitis, and infertility
Due to antigen-antibody complexes
fever, inappetence, malaise, BUN, blood urea nitrogen
Leptospirosis in dogs
_______ forms of disease in dogs: ? ( caused by ? )
Can result in kidney failure, severe liver disease, and has been fatal following shock.
Three, hemorrhagic, icteric, and uremic, L. canicola & L. icterohaemorrhagiae
Leptospira Pathogenesis
1. Bacteria enter host through a _______ or ________ __________. As few as __-__ cells can cause a fatal infection in susceptible host.
2. Enter ___________, and can persist there for up to ___ days
3. ________ _______ may be anti-phagocytic until specific antibodies are made
scratch, mucous membrane, 1-10, bloodstream, 10, Outer sheath
Leptospira pathogenesis:
1. Initial replication of organism in _____ (4-20 days incubation)
2. Organisms can also infect and persist in?
3. Once they enter tissues, can cause a ________ in small vessels, ________, and fluid _______, suggesting organism (_________) or
host-mediated (________) toxic factors
- liver
- reproductive tract, kidney, brain, and eye
- vasculitis, hemorrhage, leakage, sphingomyelinase, cytokine
Leptospira - Pathogenesis
Hematogenous spread to lungs, brain, and _________ leads to:
Fulminating hepatic and renal disease; may lead to death
or antibodies usually clear leptospires from blood and organs except ______ where they establish a _______ STATE in the _____ of nephritc tubules with no clinical signs, particularly rodents
Causes vascular damage leading to endothelial disruption via the release
of TNFα
Bile duct occlusion and jaundice
Nephritis
In _____ animals, persistence may also
occur in uterus where they can infect
fetus resulting in abortion or weak calf
KIDNEYS, kidneys, CARRIER, lumen, large
What can be seen in this image?
Leptospires in the lumen of nephritic tubules
Leptospira Transmission
Transmission: _________ _____ of pathogenic Leptospires is ________ convoluted tubules of kidney in many ______ hosts
Transmission from asymptomatic carriers
Infection by exposure to contaminated ______ through ______ or _____ skin
___________ transmission leads to abortion and stillbirths in ? (transmission also occurs through placenta and fetus)
May also be transmitted through ____
Some serovars may be transmitted in _______ (_______) from carrier animals
Some species are adapted to specific animals and are persistent
carriers (e.g. Norway rats and serovar icterohaemorrhagiae)
Natural habitat, proximal, reservoir, urine, wounds, moist, Transplacental, cattle, horses, pigs, etc. milk, semen, venereal
What microbial pathogen is pictured here? What laboratory technique is being used here?
Leptospira
Direct smear examination Silver impregnation staining
What can be seen in the image below?
Leptospira
Leptospira: Immunity
_______ is a major protective antigen
Early antibodies clear leptospires from _______ by opsonization, but may persist in some ________ protected from antibodies
________ immunity important
Ig___ and Ig__ serovar-specific antibodies
Antibodies detectable within __ to ___ days after infection
_______ does not occur again with the same serovar
Cattle with Abs to LPS may not be protected against ______ serovar (IFNγ and a Th1 response may also be important for some serovars
LPS, blood, tissues, Humoral, M, G, 5, 20, Abortion, another
Leptospira Control
Multivalent bacterin vaccines - know your _______ serovars
* Every __ months in breeding swine
* Annually in?
* ________ and _______ combination effective in outbreaks
PREVENT _________
(no bacterin contains all ____+ serovars)
local, 6, cattle, dogs and cats, Bacterin, antibiotic, EXPOSURE, 200
Leptospirosis: Diagnosis
1. ________ microscopy of _____ or _____ (may be _____)
2. Serology: 4-fold titer change between _____ and _________ samples
3. ________ __________ test [may be best test] OR (2?)
4. Isolation (Fletcher’s, Ellinghausen’s or Polysorbate liquid medium)
or passage in hamsters
5-fluorouracil can be added to contaminated specimens
Growth appears as a diffuse zone, then a ring (Dinger’s ring) near
the top of the tube (strict aerobe)
FA staining of tissues
Histopathology of kidney, liver, and brain by
silver impregnation staining
- Darkfield, urine, water, milk
- acute, convalescent
- Microscopic agglutination test (MAT), ELISA, IHA
4.
Ellinghausen-McCullough-Johnson-Harris
medium
Various salts
Thiamine
Pyruvate
Glycerol
Bovine albumin
Tween 80
B12
do not have to know
Leptospirosis:
Treatment and Public Health
Ampicillin, penicillin G, ceftriaxone, (severe cases) streptomycin,
tetracycline and doxycycline (mild cases) are effective. Some
antibiotics may not eliminate spirochetes from kidney
Therapeutic and can reduce carrier state
Prophylactic
Penicillin and similar drugs may cause Jarisch-Herxheimer (endotoxic
shock) reaction, so may need to add steroids
ZOONOSIS
*________ infection, ______ and ________ exposure
*Persons swimming in contaminated _______ at risk (especially ________)
*Weil’s disease: Acute febrile illness with jaundice, hemorrhages, pulmonary
distress, splenomegaly, nephritis, and death.
*May also present as less severe flu-like illness
Wound, mucosal, conjunctival, water, children
More than ____ _________ people contract a tropical disease known as leptospirosis each year, resulting in nearly _________ deaths
1 million, 59,000
What image can be seen below?
What can be seen in the image below?
A schematic presentation of a spirochete.
Arrow pointing to outer sheath (capsule-like properties)
What can be seen in the image below?
Icterus (jaundice)
What can be seen in the image below?
Fibrin in kidneys - lepto
What can be seen in the image below?
Interstitial nephritis - lepto
What can be seen in the image below?
Canine liver - lepto
