Nocardia + Dermatophilus

Question 1

General staining characteristics of Nocardia, Dermatophilus?

Answer 1

-Gram +ve , slow growing -Rod-coccobacillus bacteria.-Extensive branching and filamentation.

Question 2

What type of lesions do Nocardia and Dermatophilus cause?

Answer 2

pyogranulomatous lesions

Question 3

Nocardia spp. are considered to be what type of pathogen?

Answer 3

soil-borne

Question 4

What type of pathogen are dermatophilus bacteria?

Answer 4

they are obligate intracellular pathogens

Question 5

What is the most common species of Nocardia?

Answer 5

N. asteroids

Question 6

Nocardia effects what species?

Answer 6

cattle, dogs, cats, horses and humans

Question 7

Nocardia causes chronic progressive disease via what forms?

Answer 7

cutaneous, pulmonary, and disseminated forms

Question 8

A common sign of Nocardia infection in Bovine is?

Answer 8

mastitis - found on dairies Entry of Nocardia via contaminated infusion equipment.

Question 9

How is bovine mastitis due to nocardia treated?

Answer 9

Culling - No effective treatment. (novobiocin may help in early stages)

Question 10

The following clinical signs in dogs and cats can be linked to infection with? -Subcutaneous and lymph node lesions (mycetomas ) -lesions in throat, abdomen, heart, brain, liver, and kidneys -Severe halitosis (bad breath), gingivitis, and ulceration of the oral cavity are common in dogs

Answer 10

Nocardia

Question 11

Canine Nocardiosis can be confused with bot fly larvae, why?

Answer 11

Granulomatous swelling with discharging fistulous tracts appear like the “holes” formed from bot fly larvae

Question 12

Respiratory form of Canine Nocardiosis is acquired through inhalation. How does it present?

Answer 12

Fluid accumulation in thoracic cavity. Fever, respiratory distress.

Question 13

Disseminated form of Canine Nocardiosis presents how?

Answer 13

Abscesses in various organs, brain

Question 14

How is Canine Nocardiosis treated?

Answer 14

Trimethoprim sulfate or tetracyclines (penicillin is not effective)

Question 15

What dermatophilus causes skin infection of cattle, horses, sheep, goats (Occasionally dogs, cats, and humans)?

Answer 15

Dermatophilus congolensis

Question 16

What infection is known as: 1. “Rain scald”/”Rain 2. “Lumpy wool disease” 3. “Strawberry foot rot”

Answer 16

Dermatophilus congolensis infection

Question 17

What disease is highly predisposed due to ticks?

Answer 17

Dermatophilus congolensis

Question 18

D. congolensis has a long development cycle. Which portions of the cycle can cause infection?

Answer 18

only zoospores - only a free zoospore or a mature zoospore that is released

Question 19

Clinical sign of infection of D. congolensis is when you pull on the hair, the chunk of skin comes out with the hair (large patch). Why does this occur?

Answer 19

Due to the pathogenesis of the bacteria.

Question 20

What is needed for diagnosis of D. congolensis?

Answer 20

Scab material stained with Giemsa showing branching filaments (Adequate for diagnosis)

Question 21

D. congolensis is seen in three forms in what species?

Answer 21

sheep

Question 22

True or false: D. congolensis is zoonotic?

Answer 22

true; acquired from farm animals

Question 23

Diagnosis of D. congolensis requires:

Answer 23

Make smear from scab undersurface; stain with Gram’s or Giemsa. + ve if “railroad track” like hyphae seen.

Question 24

What is used as treatment of DERMATOPHILOSIS?

Answer 24

-Penicillin + streptomycin or long acting tetracyclines (I.M) -in mild cases remove scabs with mild soap and clean with iodine -reduce skin trauma and control ticks

Question 25

Concerning Nocardia and Actinomyces what statement is accurate? A. Chickens can get infection from both. B. Cattle do not get mastitis due to Nocardia. C. Both are gram negative bacteria D. Actinomyces bovis causes “lumpy jaw” in cattle E. Penicillin is effective against both

Answer 25

D. Actinomyces bovis causes “lumpy jaw” in cattle

Question 26

You saw for the first time a case of “rain scald”/ streptothricosis in a horse. Which drug will you select for treatment? a. Amphotericin B b. Tetracycline c. Ketoconazole d. Griseofulvin e. Nystatin

Answer 26

b. Tetracycline