Erysipelothrix

Question 1

What are the 2 species of Erysipelothrix of veterinary importance?

Answer 1

1. E. rhusiopathiae***
2. E. tonsillarum

Question 2

What are the 2 major morphological features of Erysipelothrix rhusiopathiae?

Answer 2

1. Gram positive
2. long, filamentous rod

Question 3

What do the filaments of Erysipelothrix rhusiopathiae cause in the host?

Answer 3

emobli

Question 4

What respiration does Erysipelothrix rhusiopathiae undergo?

Answer 4

facultative anaerobe

Question 5

How does Erysipelothrix rhusiopathiae respond to the catalase and oxidase tests?

Answer 5

catalase negative
oxidase negative

Question 6

Is Erysipelothrix rhusiopathiae motile? Spore-forming?

Answer 6

no
no

Question 7

What are the 28 serotypes of Erysipelothrix based on? Pigs are susceptible to 15 of these serotypes, what 3 serotypes of E. rhusiopathiae cause swine erysipelas?

Answer 7

• peptidoglycan antigen on the cell wall

1. 1a
2. 1b
3. 2

Question 8

What are 4 common culture media used for Erysipelothrix isolation?

Answer 8

1. blood agar
2. heart infusion + sodium azide and crystal violet
3. nutrient broth + 1% glucose
4. triple sugar iron

Question 9

How does Erysipelothrix grow on blood agar?

Answer 9

α-hemolytic

Question 10

How does Erysipelothrix grow on heart infusion agar with sodium azide and crystal violet?

Answer 10

able to ferment glucose and lactose, producine acid, but is not able to ferment maltose and mannitol

Question 11

What is the result of Erysipelothrix growing in triple sugar iron agar?

Answer 11

H2S is produced by 95% of Erysipelothrix species strains in this media (the only Gram positive able to do so), causing a foul smell

Question 12

What is the main environment for Erysipelothrix? What is its predilection site in the host?

Answer 12

slurry of cattle herds or sewage from abattoirs (frank pathogen!)

tonsils
lymphoid tissue of intestinal tracts in carrier animals

Question 13

What are the 3 most common hosts of Erysipelothrix?

Answer 13

1. pigs*** (including wild boar)
2. horses with vegetative endocarditis
3. turkey with swollen snood

Question 14

When do humans tend to become infected with Erysipelothrix? What 4 conditions does it cause?

Answer 14

occupational zoonosis (contact!) - vets, abattoir workers, butchers, farmers

1. purple-colored hardened swelling of fingers
2. endocarditis
3. pneumonia
4. meningitis

Question 15

In what 2 ways does Erysipelothrix enter their host?

Answer 15

1. enter orally to colonize tonsils
2. fly vectors

Question 16

What are the 4 ways that Erysipelothrix exit their host?

Answer 16

1. fecal*** (to spread in environment)
2. urine
3. saliva
4. nasal secretion

Question 17

Why is Erysipelothrix considered less virulent?

Answer 17

less virulence factors compared to other bacteria

Question 18

What 2 surface structures contribute to Erysipelothrix virulence?

Answer 18

1. capsule (lipopolysaccharide, slime, glycocalyx) - resistance to phagocytosis
2. surface protective proteins (spA, B, and C antigens) - biofilm formation, adhesion, elicits an immune response

Question 19

How have we used Erysipelothrix surface protective proteins?

Answer 19

incorporated into a vaccine (subunit)

Question 20

What 3 enzymes contribute to Erysipelothrix virulence?

Answer 20

1. neuraminidase (sialidase) - bacterial attachment, invasion, blood vessel destruction leading to hemorrhage and thrombosis
2. hyaluronidase - spreading via hyaluronic acid and polysaccharide destruction between adjacent cells
3. superoxide dismutase - protection from intracellular killing by macrophages

Question 21

What does the neuraminidase (sialidase) cause in the host?

Answer 21

bacterial emboli and infarction in heart valves (endocardiitis), spleen, liver, kidney, and joints (polyarthritis)

(destroys blood vessels)

Question 22

What skin problem does Erysipelothrix cause in pigs?

Answer 22

Diamond Skin disease - rhomboid urticarial skin lesions

Question 23

What skin problem does Erysipelothrix cause in turkeys?

Answer 23

acute turkey erysipelas, causing swollen and purple/dark snoods

Question 24

What skin problem does Erysipelothrix cause in humans?

Answer 24

erysipeloid - purplish, swollen, painful, hardened rash on fingers

(unlike wet and exudative skin of Strep infection)

Question 25

What 6 conditions are caused by Erysipelothrix dissemination from the skin?

Answer 25

1. endocarditis 2. pneumonia 3. meningitis 4. osteomyelitis 5. arthritis 6 abortion

Question 26

What are the 5 forms of Erysipelas based on body part tropism?

Answer 26

1. SKIN - rhomboid, urticaria,l purple/black, and hard skin lesions arond the belly, inside of thighs, throat, neck, and ears 2. RESPIRATORY - pneumonia 3. CARDIOVASCULAR - purple/black discoloration of the skin of the belly with cyanotic extremities due to septicemia, emboli, infarcts, and endocarditis that blocks heart valves 4. JOINTS - polyarthritis mainly at the elbow, hip, hock, stifle, and knee joints 5. UTERINE - abortion due to fever, but bacteria is isolated from fetus

Question 27

What are the top 2 causes of endocarditis in the pig industry?

Answer 27

1. Step. suis 2. Erysipelothrix rhusiopathiae

Question 28

How does Erysipelothrix infection compare to Staph. hyicus and Strep. suis?

Answer 28

Strep. suis manifests similar systemic clinical signs - Erysipelothrix = lacy-skin disease, no pus formation - Staph. hyicus = greasy skin - Strep. suis = contagious pyoderma

Question 29

What are the main 3 ways of diagnosing Erysipelothrix vs Staph. hyicus and Strep. suis?

Answer 29

1. clinical signs - lace-like/diamond-shape skin lesion with no pus formation 2. bacteriology - Gram positive and long/filamentous rods, catalase negative, α-hemolytic, H2S in agar 3. serology - 28 serotypes

Question 30

What are 3 common treatments for erysipelas?

Answer 30

1. penicillin 2. ampicillin 3. ceftiofur (not a member os ESKAPE)

Question 31

In what 2 ways is erysipelas controlled? Why isn't the vaccine dependable?

Answer 31

1. remove clinically sick or positive animals from herd immediately 2. good hygiene - all-in all-out policy followed by disinfection before restocking - tends to fail due to 28 serotypes - short duration of immunity (lasts less than 6 mos)