Section 3: Actinomycetes

Question 1

What are Actinomycetes

Answer 1

Actinomycetes are bacteria that have characteristics of fungi; most notably they grow in the form of mycelia. However, the cell wall structure and antimicrobial susceptibility patterns are characteristic of bacteria

Question 2

What are the two Actinomycetes that infect humans

Answer 2

1: Actinomyces sp
2: Nocardia sp

Question 3

What are Actinomyces sp

Answer 3

• Filamentous-mycelia-like
• Gram positive beaded anaerobe
• Part of the normal flora of mouth and GI tract
• Can cause abscesses following trauma to the mouth or GI tract
• Treatment is penicillin

Question 4

What are Nocardia sp

Answer 4

• Long thin filamentous structure
• Weakly Gram positive, partially acid fast
• NOT part of the normal flora
• Inhaled into lungs where creates abscess, frequently mistaken forM tuberculosis