1. Know the following characteristics about each disease studied: Genus and species name Gram reaction Cell shape Disease name Transmission Virulence factors Clinical symptoms of disease Treatment
Genus and species name: Staphylococcus aureus Gram reaction: Gram + Cell shape: coccus Disease name: Transmission: Virulence factors: Clinical symptoms of disease: Treatment:
- Be able to translate the organism’s genus and species name into the English language.
As you know, “staphylococcus” means “cluster of round, ball-shaped bacteria.”
“Aureus” is derived from “aurum,” which is Latin for “gold.” (That’s why Gold is “Au” on the Periodic Table)
- Define pyogenic.
Pyogenic (pus generating) cocci
- Define Beta-hemolytic
Beta-hemolytic: complete destruction of red blood cells
- What is the preferred site of colonization in the human body by S.aureus?
Nose is preferred site for S.aureus or moist skin
- Outline the 6 virulence factors for S.aureus and explain them.
- Hemolysins
- Protein A:
- Hyaluronidase
- Leukocidin
- Coagulase
- Capsule:
- Which virulence factors are structural parts of S.aureus bacteria cell? (Hint: there are 2)
Protein A
Capsule
- Which virulence factors are secretions by S.aureus bacteria cell? (Hint: there are 5)
- Hemolysins
- Protein A:
- Hyaluronidase
- Leukocidin
- Coagulase
- What are the differences between an exogenous, endogenous, nosocomial and opportunistic infection with S.aureus?
**not fully answered***
exogenous
endogenous: Endogenous Source
due to patients own Staph strain
Impaired host resistance (poor health, chemotherapy)
Skin wound(animal bite, burn)nosocomial: hospital acquired (extensive surgery, aseptic procedures not enforced)
opportunistic infection: Endogenous Source
due to patients own Staph strain
Impaired host resistance (poor health, chemotherapy)
Skin wound(animal bite, burn)
- What is the single most important thing that nurses and doctors can do in a clinical setting to deter transmission of nosocomial infections between patients?
Wash their hands.
- What is the CDC?
Center for Disease Control
- What are the specific differences between Folliculitis, Furuncle and Carbuncles as they relate to a Staph infection? Which one of these is most serious?
Folliculitis:
Inflammation of a hair follicle
Small red bump, pimple
Pus in the hair follicle
Causes: shaving, blockage of follicle (dirt), friction from clothing (jeans)
Damaged follicle can then be infected by Staph
Furuncle:
Round, red painful, pus-filled sore on the skin
Exterior abscess
Infected hair follicle that extends to adjacent subcutaneous tissue
Pus may drain from boil
Carbuncles:(cluster of boils)
Massive lesion, further spread of abscess
Large area of redness, swelling, pain, and several sites of draining pus
Fever present
Most serious is Carbuncles
- Define Abscess.
Pus filled: living and dead WBC, dead tissue, infectious agent
No blood vessels: destroyed or pushed aside
Helps to localize infection most oral antibiotics noneffective (absence of blood flow)
- Is an abscess treatable with only oral antibiotics? Why or why not?
No. Because a walling off abscess by inflammation may prevent antibiotics from reaching abscess in effective quantities which is one reason drainage of abscess is so important.
- Adequate drainage of abscess (lance)
- Debridement: surgical removal of necrotic tissue (dead)
- Antibiotic Therapy
- What is septicimea?
Abscesses can expand (or rupture) into the bloodstream and cause septicemia
Septic = diseased, -emia = blood
Remember, pus is poisonous garbage! You don’t want your abscess draining into your bloodstream, any more than your septic tank!
Septicemia can cause:
A massive, life-threatening, systemic infection!
Abscesses to form in the heart, bone, and joints!
Septicemia is pretty much the Worst Case Scenario of the average Staph infection
- What are the different levels of a wound infection?
Superficial: skin and subcutaneous (easiest to treat)
Deep: muscle or bone
Organ Space: involves an organ infection usually from surgical wounds (most serious)
- Is drug resistance a problem in treating S.aureus infections?
Yes!!!
- Define MRSA.
MRSA (methicillin resistant Staphylococcus aureus)
- Is MRSA treatable?
Yes but it is becoming harded to do so due to its ability to mutate.
- What is a phage (as discussed on the MRSA film)?
Virus that infects Staph infection
- Why is phage typing a useful laboratory tool in identifying different strains of Staph bacteria in a clinical setting?
Allows infection control team to compare MRSA bacteria strains and determine how many patients are infected with those strain
- Does the human body mount an effective immune response against S.aureus?
No
- What category of patient is at most risk of Staph infections?
ill patients / wound/surgery
- Outline the 6 virulence factors for S.aureus and explain them.
- Hemolysins
Hemolysins:
a) hemo: hemoglobin b) lysin: lyse c) destroy red blood cells d) β(beta) – hemolytic
