LEPTOSPIRA Flashcards
Pathogenesis is not included. Please refer on the reference book or PPT.
What serovar is primary cause of Porcine Leptospirosis?
serovar pomona
The source of Leptospira infection is from ?
- Urine from infected or carrier animal
- Water, litter, food may serve as fomites
- Direct or indirect infection via nasal, oral or conjunctival mucous membrane and abraded skin
What are the organism sources for Porcine Leptospirosis infection?
- Swine, cattle, skunks, raccoons, opossums, wildcats and deer
Equine Leptospirosis is mostly caused by serovar ?
Pomona
Leptospira use _____ and ____ as energy and _____ sources.
Long-chain fatty acids; alcohols; carbon
What are the treatment and control for Leptospira infections?
- Ampicillin, penicillin G, streptomycin, tetracycline and doxycycline
* Of no avail if renal damage is extensive - Fluid therapy in dogs
- Effective rat control
- Fencing off contaminated ponds and streams
- Screening of replacement stocks
- Susceptible to drying and heat
Leptospira spp. belongs to Spirochetes. What is the general morphology of Spirochetes?
- Spirochetes are slender, spiral, actively motile, flexible organisms, 5-200 um long and 0.1-3 um wide and divide by transverse fission
- Helically coiled and round on cross-section with varying number of spirals
Leptospira is motile by ?
2 subterminal periplastic flagella
What are the 4 principal forms of Canine Leptospirosis?
- Hemorrhagic form
- Icteric
- Uremic or subacute form
- Inapparent form
What are the diagnostic methods for Canine Leptospirosis?
- Exam of urine by dark field microscopy; formalin should be added as they autolyze very rapidly
- Microscopic agglutination test (agglutination lysis); 1:100 or higher
- Isolation, cultivation and identification
- Guinea pig or hamster inoculation; blood, urine, tissue used
- Histopathology – demo in kidney stains
- Fluorescent antibody technique in tissues and urine sediment
There are ____ L. interrogans serovars and at least ____ L. biflexa serovars.
218; 60
Give the clinical signs of Equine Leptospirosis.
- Disease usually mild or subacute with fever, depression and icterus, occasionally abortion and uveitis
- Recurrent iridocyclitis (moon blindness or periodic ophthalmia) maybe sequella
- Systemic disease rare
Serovar ____ is extremely difficult to culture.
bratislava
Leptospira has how many insertion discs?
3 to 5
_____ is extension of the axial filament shaft and bends toward the protoplasmic cylinder.
Hook
Insertion of axial filaments of Spirochetes is via ?
Proximal hook and insertion disc
In the initial stage of Canine Leptospirosis, the first 3 forms are characterized by?
Depression, anorexia, vomiting, diarrhea or constipation
Classify Leptospira acc. to its O2 requirement.
Aerobic
What are the clinical signs of Porcine Leptospirosis?
- Clinical or latent
- Unthriftiness, abortion, fever, icterus and anemia
- Occasionally, metritis and meningoencephalitis
Serovar ____ is frequent in some areas cause fewer bovine abortions than pomona but more often _____.
hardjo; infertility
What is the primary disease induced by Leptospira spp.?
Leptospirosis
What are the organism sources for Bovine Leptospirosis?
- Cattle and swine and some wild animals
- Cattle may shed for 3 months but fewer numbers and irregularly
- Outbreaks associated with heavy rainfall but infrequent under dry conditions
Give the immunity methods against Leptospirosis.
- Mainly humoral, organisms not intracellular
- Bacterins elicit considerable protection but short duration
- Bacterins not available for horses
Canine can be an incidental host for what L. serovars?
- serovars grippotyphosa
- autumnalis
- australis
- pomona
- Bratislava
Human leptospirosis is otherwise known as ?
- Well’s disease
- fort Bragg fever
- swineherd’s disease
____ ____ is plate-like and inserted into depression at end of cell.
Insertion discs
What serovar is the principal cause of Bovine Leptospirosis?
serovar pomona
First two forms of Canine Leptospirosis is caused by what L. serovar?
serovar icterohemorrhagia - hemorrhagic and icteric form
What are the other serovars that can induce Porcine Leptospirosis?
- canicola
- grippotyphosa
- icterohemorrhagiae
- bratislava
Species of Leptospira that is free living.
L. biflexa
Acute form of Leptospirosis in humans shows what c/s?
fever, jaundice and nephritis
Canine Leptospirosis is primarily caused by what serovar and less frequently by what serovar?
serovar canicola; serovar icterohemorrhagiae
Serovar _____ occasionally causes severe leptospirosis in dogs.
Grippotyphosa
Last two forms of Canine Leptospirosis is caused by what L. serovar?
serovar canicola - uremic or subacute form and inapparent form q
Species of Leptospira that is pathogenic or parasitic serovars.
L. interrogans
Give the pathogenesis of Canine Leptospirosis.
- Infection latent to severe
- Chronic progressive nephritis may follow acute canicola infection with death following long after initial infection
What are the 2 genera of Leptospira?
- Leptospira
- Leptonema
Human Leptospirosis is induced by what serovars?
- canicola
- icterohemorrhagiae
- Pomona
What are the clinical signs of Bovine Leptospirosis?
- Maybe latent and precipitated by stress
- Infections characterized by fever, diarrhea, anemia, icterus and hemoglobinuria; acute infections may result to abortion
What are the natural hosts for Leptospira spp.?
- Rodents
- Swine
- Dogs
What are 3 basic cellular elements of Spirochetes?
- Outer sheath which encompasses the cell
- Axial filament or fibril
- Protoplasmic cylinder which includes the cell wall and cell membrane
Axial filament or fibril is flagella. True or False?
False, only resembles flagella
Leptospires can be destroyed in which organ of the body?
Stomach
What serovars are implicated in abortion of equine?
- Pomona
- Grippotyphosa
Give the pathogenesis of Leptospira.
- Considerable damage to vascular endothelium
- Virulent strains produce more cytotoxic proteins than avirulent ones; exact role of protein not clear
- Hemolysin responsible for intravascular hemolysis
- Other virulence factors: motility, burrowing motility, production of hyaluronidase
- Epithelial penetration -> hematogenous dissemination -> localization and proliferation in parenchymatous organs particularly in kidney and liver -> multiplication in convoluted tubules results in carrier state or nephrosis, sometimes uremia and death
- Leptospiral antibodies and complement great. lt reduce the number of leptospires
- In carrier state, organisms shed in urine for weeks or months
- Signs are fever, anemia, subserous and submucosal hemorrhages, conjunctivitis, icterus, meningitis and agalactia
- Tissue damage results from host’s immune response
- Damage to endothelial lining results to reduction of blood flow
- Death occurs during febrile stage or later , caused by toxemia resulting from kidney and liver damage primarily humoral
- Immune response is primarily humoral
Canine and Bovine Leptospirosis have the same diagnostic methods. True or False?
True
Human treatment against Leptospirosis is effective when initiated within ___ days of onset.
4
Leptospira does not metabolize CHO but prefer?
Long chain fatty acids or alcohols
