Term
| What are normal types of skin flora? |
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Definition
- Diptheroids
- Staphylococci
- Yeasts - lipophilic, Malassezia |
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Term
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Definition
Resemple C. diphtheriae, gram positive w/ low virulence.
Break down sweat causing BODY ODOR, can cause ACNE |
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Term
| What is the most common normal flora Staph? |
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Definition
| Staph epidermidis - a nonvirulent strain. Secretes antimicrobials, preventing other colonization |
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Term
| What are the normal kinds of yeasts found on the skin? |
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Definition
| Always lipophilic, can cause rash, dandruff, or tinea versicolor - caused by Malasezzia furfur |
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Term
| What are the symptoms of a hair follicle infection? |
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Definition
Invasion of neutrophils results in pus in the follicle. Can spread to neighboring tissue, resulting in a BOIL/furuncle
Numurous boils = carbuncle - large areas of tenderness and swelling that can drain. |
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Term
| What causes a hair follicle infection? |
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Definition
Usually caused by Staph Aureus that can spread systemically.
Found in the nostrils. Once infected, continuously shed the bacteria |
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Term
| What causes are Staph aureus virulence factors? |
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Definition
- Capsule - stops phagocytosis
- Coagulase - stops leukocyte migration by producing clots
- Hyaluronidase - hyaluronic acid breakdown, extending infection
- Lipase - lipid breakdown
- Protein A - binds to Fc on antibodies, prevents opsonization |
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Term
| How are hair follicle infections treated? |
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Definition
- Decrease carried via anti-staph creams and soaps
- Draining of furuncles and carbuncles
- MOST S. aureus infections are penicillin RESISTANT |
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Term
| What is scalded skin syndrome? |
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Definition
Staphylococcus - toxins break down outer skin layer in immunocompromised **infants.
**Caused by S. aureus - exfoliatin destroy skin layers. Person-person transmission (in nurseries) |
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Term
| How is scalded skin syndrome treated? |
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Definition
- Patient isolation
- Penicillinase-resistant penicillins |
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Term
| What is a pyoderma infection? |
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Definition
An infection that generates pus:
- Furuncle
- Carbuncle
- Acne
- Impetigo - most common |
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Term
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Definition
- Group A beta hemolytic S. pyogenes most common
- Staph aureus
** after initial skin infection, antigen-antibody complexes lead to post-strep acute glomerulonephritis |
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Term
| What population carries Impetigo? |
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Definition
Children 2-6 living in poor areas
**Prevention by cleanliness and avoidance, Tx using penicillin and erythromycin |
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Term
| Where does Rocky Mountain Spotted Fever originate and what causes it? |
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Definition
rash at the palms/wrists and ankles/feet. Caused by Rickettsia rickettsii
**Can result in death if spreads to the HEART and KIDNEY |
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Term
| What is Ricketsiaa rickettsii |
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Definition
Intracellular anaerobes that REQUIRE the host organism.
Gram-negative, non motile cocci that are very small
**Acquired from tick bites, an endotoxin is released to cause disseminated intravascular coagulation) |
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Term
| How is rocky mountain spotted fever prevented and treated? |
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Definition
- Prevention - tick prevention and removal
- Doxycycline and chloramphenicol |
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Term
| What are the stages of Lyme Disease? |
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Definition
- First Stage - erythema migrans (skin rash) and flu-like symptoms
- Second stage - 2-8 weeks post rash involving heart/nervous system. Partial paralysis and emotional instability
- Third stage - arthritis of large joints in 60% of untreated cases, chronic nervous impairment |
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Term
| What causes Lyme diseases? |
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Definition
Borrelia burgdorferi, a spirochete. Suppresses host immunity
**Antibiotics effective in EARLY stages |
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Term
| What are the causitive agents of skin infections? |
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Definition
- Infected hair follicle --> furuncle --> carbuncle - Staphylococcus aureus (gram +)
- Scalded Skin Syndrome - Staph aureus (gram +)
- Impetigo - Usually Streptococcus pyogenes(gram + group A), sometimes Staph aureus (gram +)
- Rocky Mountain Spotted Fever - Rickettsia rickettsii (Misc)
- Lyme Disease - Borrelia burgdorferi (Spirochete) |
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