Organisms Encountered In Clinical Practice

Question 1

Describe guided therapy

Answer 1

• antibiotic has limited action to causative bacteria
• limited penetration to site of infection
• aim is to achieve a clinical cure with little impact on colonisation
• narrow spectrum antibiotics

Question 2

Describe empirical therapy

Answer 2

• antibiotic with extensive action against causative bacteria
• broad penetration of infection site
• achieves clinical cure with impact on colonisation
• broad spectrum antibiotics

Question 3

Describe important features of S. aureus

Answer 3

• gram-positive cocci
• form grape-like clusters
• usually form skin and soft tissue infections, can form disseminated infection in serious cases
• MRSA = methicillin-resistant S. aureus (difficult to treat)

Question 4

Describe important features of streptococci

Answer 4

• gram-positive cocci
• form chains
• usually form skin, soft tissue and GIT infections (sometimes GU)

Question 5

Describe important features of Coliforms

Answer 5

• gram-negative Bacilli
• usually form infections of urinary tract and abdomen (eg. UTIs and diverticulitis)

Question 6

What are some examples of difficult gram negatives to treat with antibiotics?

Answer 6

• pseudomonas aeruginosa (virulent)
• E. Coli (less virulent, vulnerable patients more at risk)

Question 7

Describe important features of anaerobes

Answer 7

• can be gram-positive or gram-negative
• grow in areas depleted of oxygen so tend to form infections such as abscesses