Leptospira Flashcards
Leptospira Gram___? Shape?
Gram Negative Classic spirochetes Diverse, many variations/serotypes
Leptospira Motile/Non-motile?
Motile
Leptospira Distribution? Reportable?
Worldwide. REPORTABLE in USA
Leptospira Disease Patterns Hallmark sign
Late-term abortion
Leptospira Disease Patterns Dogs
Septicemia - Hepatic & Renal Disease
Leptospira - Disease Patterns Cattle & Swine
Septicemia in young Abortion in adults
Leptospira - Disease Patterns Horses
Abortion & uveitis (moon blindness)
Leptospira - Disease Patterns California Sea Lions
Acute septicemia
Leptospira - Disease Patterns Humans
Acute febrile disease
How is Leptospira best visualized on microscopy?
Dark-field or phase-contrast microscopy
Leptospira Cell wall description
LPS with feeble endotoxin
Leptospira Stable/Labile in environment? What kills it?
Weak/Labile Killed by drying, freezing, heat, detergents, bile salts, acidic environment
Leptospira Where can it persist in environment?
Moist, temperate environment @neutral or slighly alkaline pH
Leptospira What type of agar does it grow on?
It doesn’t! GOTCHA! No agar! Usually grown in fluid or semi-solid media
Leptospira Oxidase Pos/Neg?
Oxidase positive
Leptospira Catalase Pos/Neg?
Catalase positive
Leptospira Urease & Lipase Pos/Neg?
Some are lipase & urease positive
Leptospira How is advanced identification established?
Serology (PCR still in development
Leptospira Reservoir
Tubule of Mammalian kidneys! Especially rodents! Wild carnivores, birds, reptiles, amphibians, invertebrates too
Leptospira Transmission
Urine contamination! **Bodies of water** Fluid/fomite/feed contacts skin/mucous membranes. Milk in acutely infected cows
Leptospira Pathogenesis
Spirochetes enter bloodstream–> Colonize liver and/or kidney (also muscle, eyes, meninges)
Leptospira Clinical Signs/Pathology
>Nonsuppurative meningitis, hemorrhages >L. serovar Pomona in Cattle (intravascular hemolysis) >Autoimmune diseases, Icterus (liver damage & blood destruction) >Acute, subacute, chronic nephritis
Leptospira Dogs Most important serovars
**Canicola** Iceterohemorrhagiae Grippotyphosa
Leptospira- Dogs Acute form -Describe & is it fatal?
Puppies! Fever, hemorrhaging mucus membranes, epistaxis, blood-stained feces Fatal within days
Leptospira-Dogs Icteric form
Less conspicuous hemorrhage Prominent Icterus Renal casts & leukocytes in urine
Leptospira- Dogs Uremic form
*Kidneys* with or without other two forms Acute & rapidly fatal GI upset, uremic breath, GI ulcerations
Leptospira - Dogs Name the three forms
Acute Form Icteric Form Uremic Form
What is this dog infected with?
Acute Leptospirosis! Likely Icteric form
Name the organ, name the pathogen, describe the lesion,
Lung -Dog Leptospirosis Petechiae scattered throughout lung
Name the organ, name the pathogen, describe the lesion
Kidney - Dog Leptospirosis Pale mottled to striated cortex consistent with tubulointerstitial nephritis
Leptospira - Cattle Most common manifestation? Exact cause?
Abortion! Mostly late-term Fetal death NOT placental infection
Leptospira - Cattle Serovar Hardjo Disease nickname
“Weak Calf Syndrome”
Leptospira - Cattle Serovar Hardjo Clinical signs
“Weak Calf Syndrome” In utero infection Repro failure & infertility Chronic infection in kidneys–>urine shedding
Leptospira - Cattle Serovar Pomona Acute/Chronic? Most affected?
Acute leptospirosis in calves, some adults
Leptospira - Cattle Serovar Pomona Clinical signs - Fatality rate
Fever, hemoglobinuria, icterus, anemia Fatality rate = 5-15%
Leptospira - Cattle Serovars Grippotyphosa, Icterohemorrhagiae, Canicola
May cause bovine infections, certain parts of world
Leptospira- Swine Serovars affecting them:
Pomona Icterohemorrhagiae Canicola Taravossi Bratislava Muenchen
Leptospira- Swine Disease Pattern
Septicemia with icterus and hemorrhage -Usually piglets
Leptospira- Horse Serovars affecting them:
Pomona Grippotyphosa Icterohemorrhagiae
Leptospira-Horse Disease Pattern
Fever Mild Icterus Abortion
Leptospira- Horse Effect on eye:
Icteric conjunctiva
Equine recurrent uveitis -Periodic ophthalmia -Moon blindness -Equine recurrent iridocyclitis
Leptospira-California Sea Lion Serovar?
Pomona
Leptospira-California Sea Lion Disease Pattern?
Periodic mortalities
Leptospira-Humans Serovars?
Susceptible to all serovars
Leptospira-Humans Disease Pattern
Fever Icterus Muscular pain Rashes Non-suppurative meningitis
Leptospira-Humans What disease pattern is associated with serovar Icterohemorrhagiae
Fatal liver or renal disease
What immunoglobulins are associated with recovery from a Leptospira infection?
Circulating IgM and IgG
Leptospira- Do recovered animals have lasting immunity? Any exceptions?
Yes. Very effective and serovar-specific immunity (Except multiple Hardjo abortions in cows reported)
Leptospira What species do serovar-specific vaccines exist for?
Dogs Cattle Swine Humans –Temporary immunity-Boosters
Leptospira - Lab Diagnosis Live samples collected
Not milk! -Blood *Urine* -CSF -Uterine fluids -Placental cotyledons
Leptospira-Lab diagnosis Necropsy samples collected
*Kidneys*, liver, spleen, lung, brain, eye
Leptospira- Direct Exam Stains used?
-PCR -Wet mount stains: Darkfield IFA Silver Stains
Leptospira- Culture medium
May be attempted in EMJH medium
Leptospira- Intraperitoneal inoculations
May be attempted Kidneys examined Serological assays
Leptospira-Serology -Test used?
Common/Best for Dx Microscopic agglutination test
Leptospira- Serology What samples are best for Microscopic agglutination test?
Paired samples preferable with increasing titer
Leptospira-Other diagnostic tests?
Complement fixation Other agglutination tests ELISA
Leptospira- Treatment Antibiotic resistance?
Generally low resistance High susceptibility
Leptospira- Treatment Antibiotics used?
Penicillin Streptomycin Tetracyclin Chloramphenicol Erythromycin
Leptospira-Treatment When is the most effective time to treat?
Must be started early in infection or prophylactically
Leptospira-Treatment What develops in cattle with sustained infection?
Biofilms
Leptospira- Vaccination?
Prevents clinical disease -Infection and shedding still can occur
