Infections of the Musculoskeletal System I (30) Flashcards
Dr. Erol
What family does genus borrelia fall under?
family spirochaetaceae
What are the characteristics of borrelia burgdorferi?
gram-negative
better visualized if stained with silver, gems, wright’s stains, or dark field microscopy
What is this visualization method? Which bacteria?
dark field microscopy
borrelia burgdorferi
What kind of pathogens are borrelia burgdorferi?
obligate pathogens
Regarding borrelia species, spirochetes are transmitted and maintained by ____
ticks - are obligate parasites in a variety of vertebrate hosts
What is the causative agent of Lyme disease?
borrelia burgdorferi sensu lato
tick-borne: ixodes scapularies, l. pacificus, etc
Who are normally the reservoir for borrelia species regarding Lyme disease?
rodents
What is the lifecycle of ixodes scapularis?
adult females drop off host to lay eggs
eggs hatch into six-legged larvae
larvae attach - go to second host
nymphs - molt into adults and leave for third
attach to third host
What are the stages of Lyme disease?
early localized rash
early disseminated stage
late disseminated stage
What is characteristic of the early localized stage in Lyme disease in humans?
red, expanding rash: erythema migrans
fatigue, chills, fever, headache, muscle and joint aches, swollen lymph nodes
What is characteristic of the early disseminated stage in Lyme disease in humans?
facial or Bell’s palsy
severe headaches and neck stiffness
pain and swelling in the large joints
shooting pains that may interfere with sleep
What is characteristic of the late disseminated stage in Lyme disease in humans?
months to years post-tick bite
arthritis, with severe joint pain and swelling
What is the most common clinical manifestation of Lyme disease in humans?
erythema migrans - 70%
T/F: It is common for the vast majority of dogs in endemic areas to be seropositive for Lyme disease
TRUE
When are clinical signs of Lyme disease seen in dogs? What are the general clinical syndromes?
2-5 months after tick exposure
polyarthritis and glomerulopathy
What are the characteristics of Lyme arthritis?
fever
shifting leg lameness
articular swelling
polyarthritis
lymphadenomegaly
anorexia
general malaise
A dog is having shifting leg lameness and has a fever of 104 F. He recently traveled to the northeast coast and is not on tick prevention. What is a possible disease and causative agent?
Lyme arthritis
caused by borrelia burgdorferi
What are characteristics of Lyme nephritis?
sudden onset of anorexia, vomiting, lethargy, and weight loss
uremia, hyperphosphatemia, and severe protein-losing nephropathy
lodging in immune complexes in kidneys
What are clinical signs of Lyme disease in horses?
chronic weight loss
sporadic lameness
muscle tenderness
changes in behavior and skin sensitivity
neurological signs
List the tick vectors and natural hosts of borrelia species
ixodes spp.
argas spp.
ornithodoros spp.
What tick and causative agent is associated with epizootic bovine abortions?
ornithodoros spp.
B. coriaceae
What is pathognomonic of borreliosis?
no specific hematologic or biochemical changes
If a dog in a Lyme disease endemic area has leukopenia or thrombocytopenia, these hematologic changes are likely caused by infection or _____ with a ______ pathogen
co-infection
rickettsial
Synovial fluids of Lyme arthritic dogs have increased cell counts of ____ to _____ cells/microL with neutrophils predominating
5,000 to 100,000
What are the serological assays?
whole-cell ELISA and immunoblot
C6 peptide-based assays
multiplex assays
What is a whole cell-ELISA assay?
antibody measurements using whole spirochetes
In whole cell-ELISA, antigen preparations, techniques, and interpretations of different laboratories are ______
not standardized
What test can have cross-reactivity with leptospira-positive sera, and sera from other disease moieties?
whole cell-ELISA
What is whole cell-immunoblotting?
helps identify sera that produce false-positive results in whole-spirochaete assays
Regarding whole cell-immunoblotting, after _____, antibodies develop to proteins in the range of 58, 41, 39, and 23 kDa
natural exposure
What does a C6-peptide based assay do?
detects antibodies against C6 peptide, the invariable region of the borrelial protein VlsE
What does C6-peptide based assays differentiate between?
vaccinated and naturally infected dogs
What are C6-peptide based commercial assays?
SNAP 4Dx Plus Test
Lyme Quant C6 Test
After treatment, C6 antibodies [ascend/decline] sharply after treatment
decline
How do you treat Lyme disease?
acute: beta-lactams and tetracyclines
chronic: longer therapy
How do you prevent Lyme disease?
tick control
vaccines, bacterins, and subunit vaccines available
How do you prevent Lyme disease in dogs?
collars
topical powders, shampoos
daily combing and tick removal
How do you prevent Lyme disease by vaccines?
recombinant
killed
