Chapter 22: Skin Infections - Impetigo, Acne, Lyme Flashcards
What bacteria causes impetigo? (2)
- most common is Streptococcus pyogenes
- also can be cause by S. aureus
How do you get impetigo?
- usually requires a wound to penetrate the outer layers of skin
- ex. cut, bite, or scratch
What does impetigo result in? (3)
- inflammation of the epidermis
- results in a thin-walled blister
- blister will break to release oozing plasma
What happens after the blister oozes plasma in impetigo?
- bacteria spread to other areas of the skin
how is impetigo transmitted?
- direct or indirect
How is impetigo treated?
antibiotics
what bacteria causes acne vulgaris? (inflammatory acne)
- Propionibacterium acnes
- a member of the normal microbiota
How does acne vulgaris grow? (2)
- grows anaerobically in hair follicles
- eats sebum (oil secreted by skin)
What does acne vulgaris result in? (2)
- during periods of excess sebum production, follicles can become blocked
- P. acnes overgrows and triggers inflammation
How is acne vugaris treated? (3)
- antibiotics
- benzoyl peroxide
- isotretinoin (accutane) to redue sebum production
What are some side effects of isotretinoin? (2)
- depression
- birth defects
What bacteria causes lyme disease? (2)
- Borella burgdorferi
- Spirochete - tightly wound corkscrew shape
Who does lyme disease commonly effect?
- deer and mice because they are reservoirs
How is lyme disease transferred to humans?
- ticks because they are VECTORS
What are the symptoms of the first stage of lyme disease?
- bullseye shaped rash appears at the bite
- followed by fever, muscle pain and headache
How long does the first stage of lyme disease last?
up to 2 weeks
How long does the second stage of lyme disease last?
- weeks to months after infection
What are the symptoms of the second stage of lyme disease? (3)
- arthritis
- facial paralysis
- irregular heart rhythm
When does the third stage of lyme disease happen?
months to years later
What are the symptoms of the third stage of lyme disease? (2)
- chronic arthritis
- neurological changes (memory, mood, and sleep disturbances)
How would you treat lyme disease?
- antibiotics during the first stage ONLY
Why would you get arthritis and neurological changes in lyme disease?
likely due to autoimmune response
