Filamentous Bacteria Flashcards
True/False: Filamentous bacteria is a group of different generas of bacteria at some point in the growth they form a filamentous form
True
What are the most important generas of filamentous bacteria?
Nocardia
Actinomyces
Dermatophilus
All the filamentous bacteria are gram ______
positive
True/False: Nocardia is anaerobic, gram positive and saprophytic
False: Nocardia is aerobic
Nocardia are _____ acid- fast
partially
*They can show up as both acid fast positive or negative
*some mycolic acids of nocardia are simple while other are more complex
What kind of exudate does Nocardia produce?
suppurative and pyogranulomatous
Which species of nocardia is the most common?
Nocardia asteroides
True/False: Nocardia is mainly opportunistic
True
immunosuppressed individuals are more at risk
What immune response is needed agasint Nocardia?
Cell mediated
What is the reservoir for nocardia and how is it transmitted?
soil and water
transmitted via inhalation, trauma, and ingestion
True/False: nocardia can cause mastitis
True
Nocardia creates a suppurative process with variable ______ features
granulomatous
Lymph nodes are usually ______ in Nocardia infections
enlarged
*LYMPH NODES ARE CONSISTENTLY INVOVLED WITH NOCARDIA
Nocardia has exudates with blood, pus and _____ like granules
sulfur
*Sulfur granules are more common in actinomyces
Nocardia is one of the causative agents for ______ farcy
bovine
True/False: Nocardia can cause pneumonia, abortion, and lymphadenitis
True
What are the features of Bovine farcy?
Placenta covered with multiple foci
multiple lesions in the lung
Nocardia is most susceptible for _______horses, swine, dog and cats
immunosuppressed
Nocardia causes important mortality events in what species?
dogs and cats
50% case fatality
Nocardia is the causative agent of what disease in the jaw?
Mandibular osteomyelitis (lumpy jaw)
What is this a picture of?
sulfur granules
*colonies of bacteria within the mandible
Chronic osteomyelitis from Nocardia give a ______-like appearance to the mandible
honeycomb
True/False: Nocardia is morphologically indistinguishable from actinomyces
True
What agar can you grow Nocardia on?
Sabouraud’s and blood agar
*Nocardia looks similar to fungi when it grows
Ture/False: Nocardia are falcultative aerobes
False
Nocardia are OBLIGATE aerobes
What is the most recommended drug for nocardosis treatment?
Trimethoprim- sulfonamide
True/False: Actinomyces is found as part of the normal flora of the mouth, GI tract, and urogenital tract and cause endogenous infections
True
One virulence factor of Actinomyces is ______ which cleaves sialic acid and open up receptors for the bacteria to bind to
Sialidase
Is Actinomyces acid fast positive?
NO
ACID FAST NEGATIVE- They do not contain mycolic acid
What kind of reactions do Actinomyces evoke?
Pyogranulomatous
What is the difference between the pathogenesis of Nocardiosis and Actinomyces?
Actinomyces has little tendency for vascular dissemination!
Actinomyces pathogenesis
- trauma opens the door for endogenous bacteria to colonize
- pyogranulomatose lesions evoking an intense response
- osteomyelitis is initiated
- replacement with porous bone, dislodgement of teeth, inability to chew
True/False: Only Nocardia causes lumpy jaw
False
*Both Nocardia and Actinomyces cause lumpy jaw
True/False: It is more common to see lymph node involvement in Nocardia than Actinomyces
True
What species of animal is more common to get lymph node invovlment by Actinomyces
Horses
*Common to see infections in cervical lymph nodes in horses with Acintomyces
How can dogs and cats transmit Actinomyces?
Bites
True/False: In Actinomyces, there could be antibodies but the main immune response that is protective is the cell mediated response
True
_______granules are VERY common with Actinomyces infections
Sulfur
*look like pepple lesions coming out of the wound
True/False: Actinomyces are obligate anaerobes
False
Facultative anaerobes
Actinomyces requires _____ in the agar to grow
serum or blood
What can be used as a treatment for Lumpy jaw?
Iodine
True/False: Dermatophilus congolensis is mainly found in the tropical areas and can cause severe economic losses
True
Dermatophilus is associated with warm weather, wet weather and _____
ticks!
Dermatophilus causes a _____epidermitis in livestock
exudative
Dermatophilus congolensis forms coccoid forming _____filaments
branching
What is the best treatment for Dermatophilus?
if the animal is removed from the rain it will most likely recover
reduce the tick population
PREVENTION is key!
