Gram Positive Rods

Question 1

Name the Three Gram Positive Rods

Answer 1

• Erysipelothrix rhusiopathiae
• Lactobacillus
• Propionibacterium

(Gram Positive Rods)

Question 2

Where is Erysipelothrix rhusiopathiae found?

(Gram Positive Rods)

Answer 2

• Pathogen and colonizer of animals, mammals, birds, fish, especially turkeys and swine.
• Disease in humans is zoonotic and primarily occupational abattoir workers, butchers, veterinarians*

Question 3

Where does Erysipelothrix rhusiopathiae enter?

(Gram Positive Rods)

Answer 3

• Enters through abrasions and wounds
• Localized skin infection = erysipeloid*
• Local swelling and redness of skin
• Does not suppurate (no pus)
• Differentiates it from Strep erysipelas
• Self limited, but can treat with antibiotics

Question 4

Is Erysipelothrix rhusiopathiae considered bacteremia?

(Gram Positive Rods)

Answer 4

• Rarely bacteremia, sepsis, and endocarditis

Question 5

Erysipelas is caused by what?

(Gram Positive Rods)

Answer 5

• Erysipelas = bacterial skin infection caused by Strep. pyogenes

Question 6

What pig infection is caused by E. rhusiopathiae?

(Gram Positive Rods)

Answer 6

Swine Erysipelas

Question 7

What human infection is caused by E. rhusiopathiae?

(Gram Positive Rods)

Answer 7

Erysipeloid

Question 8

Laboratory Diagnosis of Erysipeloid

(Gram Positive Rods)

Answer 8

• Usually must biopsy the lesion to get positive cultures; organisms not found on the red surface
• Can be seen with Gram stain
• Not difficult to culture

Question 9

What is the importance of culturing Erysipeloid?

(Gram Positive Rods)

Answer 9

Must be differentiated from Corynebacteria

Question 10

How do you treat Erysipeloid?

(Gram Positive Rods)

Answer 10

• Penicillin
• If at risk, individuals should wear gloves (Swine get vaccinated for Erysipelothrix)

Question 11

What is the normal flora of Lactobacillus.

(Gram Positive Rods)

Answer 11

• GI tract
• Vagina Important in maintaining pH of 4.5 which prevents yeast (Candida overgrowth)

Question 12

Is Lactobacillus disease causing?

(Gram Positive Rods)

Answer 12

No

Question 13

Lactobacilli are used as probiotics. Why?

(Gram Positive Rods)

Answer 13

Restore normal flora after imbalance created by antibiotic therapy

Question 14

Lactobacilli is used extensively in the food industry. What is it used to make?

Answer 14

• Production of sour milk, yogurt, cheeses
• Pickles, sauerkraut, sourdough breads, etc.

Question 15

Propionibacterium

(Gram Positive Rods)

Answer 15

• Gram-positive rods
• Normal flora of skin
• Medical importance:

–Implicated in acne vulgaris

–Common contaminants of blood cultures and body fluid cultures