microbio ch. 22 - skin infections

What skin diseases are caused by Staphylococcus aureus? 

food poisoning, hair follicle infections, impetigo, infective endocarditis, staphylococcal scalded skin syndrome, toxic shock syndrome

What virulence factors does S.aureus possess? 

What roles do these virulence factors of S.aureus play in causing disease or evading the host immune system?

Describe the characteristics of folliculitis, furuncles/carbuncles, and boils.

How do folliculitis, furuncles/carbuncles, and boils develop?

What virulence factors contribute to abscess formation in the case of folliculitis, furuncles/carbuncles, and boils?

Where do the infecting microbes come from for folliculitis, furuncles/carbuncles, and boils?

What are the symptoms of staphylococcal scalded skin syndrome?

malaise, irritability, fever, sensitive red rash with sandpaper texture, large blisters, peeling of outer skin layers

Why do some strains of S. aureus cause this syndrome while others don’t?

What toxin is associated with staphylococcal scalded skin syndrome and what is its mechanism of action?

strains of Staphylococcus aureus that produce exfoliative toxins

How is staphylococcal scalded skin syndrome treated?

antibiotics; remove dead tissue; isolate patient to limit spread of the pathogen to others and to prevent secondary infection.

What are the etiological agents of impetigo?

What are the symptoms of impetigo?

non-bullous impetigo: papules, vesicles, then pustules that break, releasing plasma which dries, forming yellowish crusts. Bullous impetigo: large, gradually darkening blisters (bullae), no crusts

How is impetigo spread and where do the organism that cause the disease originate?

organisms enter the skin, sometimes through minor breaks; some S. pyogeness trains that cause impetigo can also cause glomerulonephritis; exfoliative toxin-producing S. aureus causes bullous impetigo: Staphylococcus aureus, Streptococcus pyogenes

How is impetigo treated?

appropriate antibiotic, topical or oral

What disease can occur as a result of Streptococcus pyogenes caused impetigo? 

What are the characteristics of the disease? 

What causes the symptoms of the disease?

What is the etiological agent of Rock Mountain Spotted Fever?

What are the symptoms of Rock Mountain Spotted Fever?

headache, muscle and joint pain, and fever, followed by a rash that begins on the extremities

How is Rock Mountain Spotted Fever spread?

What is the pathogenesis of Rock Mountain Spotted Fever?

organisms multiply at site of tick bite, invade the bloodstream, and then infect endothelial cells; blood vessel involvement and systemic inflammatory response damage tissues.

How is Rock Mountain Spotted Fever prevented and treated?

appropriate antibiotics; avoid tick-infested areas; use tick repellent; remove attached ticks.

What is the etiological agent of chicken pox?

What are the symptoms of chicken pox?

fever, headache malaise; itchy bumps and blisters in various stages of development; latent infections can reactivate, resulting in shingles.

How is chicken pox spread?

What is the pathogenesis of chicken pox?

virus enters the respiratory tract, replicates in lymph nodes, and is carried in the bloodstream to the skin; there it spreads locally, resulting in development of the characteristic rash.

How is chicken pox prevented and treated?

antiviral medication; attenuated vaccine, post-exposure prophylaxis with VAR (vaccine) or VARIZIG (hyperimmune globulin). Shingles incidence can be significantly reduced with recombinant zoster vaccine (RZV).

What disease occurs later in life due to a reactivation of the Varicella virus? 

What are the symptoms of this disease? 

What is the etiological agent of measles? 

What are the symptoms of measles?

How is measles spread?

What is the pathogenesis of measles?

How is measles prevented and treated?

What is the etiological agent of German measles?

What are the symptoms of German measles?

How is German measles spread?

What is the pathogenesis of German measles?

How is German measles prevented and treated?

Why is German measles of special concern to pregnant women?

What group of fungi cause skin diseases? 

What enzyme do these fungi possess and what is its function? 

What yeast is a frequent cause of diaper rash?

How are fungal skin diseases prevented and treated?