Infectious Diseases

Question 1

What is bacteria

Answer 1

• unicellular microorganism with shapes including curved rods, spheres, rods, and spirals
• when bacteria form a parasitic association with other organisms, they are classified as pathogens.
  
  • pathogenic bacteria are a major cause for human death and disease

Question 2

describe gram stain classification for bacteria

Answer 2

-developed by Hans Christian Gram, bacteria is characterized into the structural characteristics of their cell walls
Gram POSITIVE bacteria appear blue/violet
Gram NEGATIVE bacteria appear red/pink

Question 3

By combining morphology (shape) and Gram staining, most bacteria can be classified into these four groups

Answer 3

1. Gram Positive Cocci (round)
2. Gram Positive Bacilli (rod-like)
3. Gram Negative Cocci (round)
4. Gram Negative Bacilli (rod-like)

Question 4

Typical Gram positive infections

Answer 4

Staphylococcus aureus - skin infections
Streptococcus (razor blades in throat)
-Respiratory tract infections
-Strep throat
-Endocarditis (inflammation/infection of heart valves)
-Necrotizing fasciitis (“Flesh Eating” disease)

Question 5

Typical Gram negative infections

Answer 5

1. Neisseria - Meningitis, Gonorrhea
2. Pseudomonas - Pneumonia
3. Hemophilus - Pneumonia
4. Escherichia coli (E.Coli) - Urinary Tract Infections
5. Proteus - Bacteremia
6. Bacteroides - Abdominal Infections

Question 6

What is Methicillin Resistant Staph Aureus (MRSA) and how is it transmitted

Answer 6

Caused by staphylococcus aureus bacteria that thrives on human skin and mucus membranes. it can be carried by the host for a long time without causing clinical consequences

Transmitted: person-person contact, especially through hands of health care workers.

Question 7

ways of transmitting/preventing MRSA

Answer 7

person to person contact
the nasal carriage is very common and may be due to nose/hand contact. carrier often contaminates own hands via nose/hand contact and spreads the organism in the course of routine activities.
PREVENTION: WASH YOUR HANDS!!!
A culture of nares, rectum, or skin can detect colonization

Question 8

What is colonization of MRSA

Answer 8

indicates the presence of the organism without any symptoms of illness.

Question 9

How can one be colonized with MRSA

Answer 9

Can occur in the nares, trachea, rectum, skin folds, or in an open wound. The Pt will not display symptoms once colonized.
20-30% of general population are colonized with MRSA
healthcare workers most likely high because increase exposure
-colonization is not an indication for hospital admission or prolonged hospitalization

Question 10

what is infection of MRSA. signs/Sx

Answer 10

tissue invasion by S.Aureus with clinical symptoms.
infection can range from superficial skin lesions (boils) to deeper pneumonia, bacteremia (which can progress to death)
Sx: systemic diseases such as fever, malaise, leukocytosis

Question 11

treatment for MRSA when admitted to hospital

Answer 11

Antibiotic options

1. Vancomycin
2. Clindamycin
3. Linezolid
4. Quinupristin/Dalfoprisitn