Ch. Twenty One: Diseases of the Skin and Eyes Flashcards
1
Q
Staphylococcus aures: Direct Invasion
A
- produce coagulase
- antibiotics used: penicillin
1. Foliculitis: ex. sty; infect hair follicle
2. Furnicle: ex. boil - type of abscess, localized region of pus surrounded by inflamed tissue; red, swollen, pain and yellow pus
- antibiotics do not penetrate well
3. Carbuncle: - hard, deep inflammation of tissue under skin
- draining pus; becomes systemic (surgical intervention)
2
Q
Staphylococcus aures: Scalded Skin Syndrome (SSSS)
A
- exotoxins: Exofoliative- cause separation of the skin layers (break ester bonds)
- affects children and the elderly
- communicable: isolation or B-lactam
- danger: 2 degree infections (fungus and pseudomones)
causes: - red (20-100%) skin and genitialia (painful)
- form blisters with clear fluid
- skin peels off in sheets
3
Q
Staphylococcus aures: Impetigo
A
- of the newborn
- spread by direct contact is contagious
- is a pyoderma (pus-filled) of the epidermis
- causes: local inflammation- lymph nodes
- yellowish crusts form
4
Q
Staphlyococcus aures: TSS
A
- ex. tampons, surgery, and childbirth
- causes: fever, headaches, nausea, vomiting, diarrhea, confusion (CNS), delirium, blood shot eyes, skin may peel off- SSS, and shock, kidney failure
reason: - exotoxin toxic shock syndrome toxin 1 (TSST-1); superantigen
tampons: - depletes Mg+ ions from vaginal fluid, abrade the epithelium, nutrient rich region (blood-soaked)
precaution: - change tampon based on absorbency
- hand washing (before and after)
- episodes: prevent by changing manufactures
- limit destruction of abrasion of epithelium
5
Q
Streptococcus pyogenes: Impetigo
A
- of older children and elderly
- is a pyoderma of epidermis
6
Q
Streptococcus pyogenes
A
- Group A beta-hemolytic
- hemolysins (lyse red blood cells), streptokinases, hyaluronidase
- further differentiated into groups designated A-T
- group A is divided into over 80 immunological types according to the antigenic properties of M protein
7
Q
Streptococcus pyogenes: Erysipelas
A
- effects dermal layer of skin
- skin erupts into reddish patches with raised margins
- can progress to local tissue destruction and even enter the bloodstream causing sepsis
- first appears of face and mouth
treatment: B-lactam type antibiotics (cephalopsorin)
8
Q
Streptococcus pyogenes: Necrotizing fascitis
A
- flesh eating disease
- breaks down fascia (connective tissue fibres)
- failure of organs- death is 50%, or amputation
- enter through minor skin breaks
- produce exoenzymes from M-protein
- exotoxin A acts as a superantigen causing immune system to contribute damage (toxemia)
9
Q
Pseudomonads aeruginosa
A
Dermatitis:
- self-limiting infection
- causes skin rash
- swimming pools, and pool-type saunas, and hot tubs
Otitis externa:
- “swimmer’s ear”
- effects ear canal
- lake water
Burn wounds:
- filled with blue-green pus
- 2/3 patients require longer hospitalization or increased mortality
Opportunistic: hiding from immune cells
- cystic fibrosis and cancer patients are vulnerable
- spread and grow in flowers and mop water (stagnant)
10
Q
Warts
A
- HPV (50types)
- vaccine only takes care of 4-5 strains (16, 18, 11, 6)
- spread: hand, fomites. and sexual contact
- growth: nipple-like protrusions- contact live virions; epidermis
- incubation period: weeks/months; hard to trace back to source
- treatment: Cryotherapy (liquid nitrogen), electrical current (electrodesiccation), laser, and Salicyclic Acid (requires repetition and time)
- associated with cancers (genital warts)
11
Q
Herpes Simplex Virus 1
A
- cold sores or fever blisters
- spread: orally and respiratory route
- latent: CN 5 (trigeminal nerve)
- reoccurrence: stress, sunlights, menstruation, infection
- no treatment needed
- Herpetic Opthalmia (goes to eyes)
- Hepetic Whittlow (Brachial nerve)
12
Q
Herpes Simplex Virus 2
A
- genital herpes forming deep sores
- sexual contact
- sacral ganglia (peripheral nerves)
- danger: move to brain and cause encephalitis
- treatment: Acyclovir
13
Q
Herpes Simplex Virus 3
A
- Varicella-zoster
- Chickenpox= Shingelles
- spread: respiratory route, enters blood, affects skin (14-21 day incubation)
- example of an exanthem (skin rash from another infection)
- macule, papule, vesicle, PUSTULE, crust, then possibly scar
- fever reducing drugs are not needed; will cause Reye’s syndrome (liver and brain damage) in 5-15 year olds
- latent: enter peripheral nerves and moves to central nerve ganglion; dorsal root- can be reactivated as Shingelles
- vaccine: Live attenuated vaccine at age 13 or Acyclovir
14
Q
Smallpox
A
- variola appears as pustules
- high mortality rate
- spread through respiratory and fomites
- permanent scar
- eradicated
15
Q
Rubeloa (Measles)
A
- red, hard
- extremely contagious spread by respiratory route
- in children and pregnancy it is deadly
- also found in 19-24 year olds
- causes: still births, miscarriages
- signs: begins as common cold, conjunctivitis, macular rash, oral mucosa- Koplik’s spots (central white-blue specks)
- can reach otitis media- infections, pneumonia, and go in blood reaching brains causing: Encephalitis, subactue sclerosing panencephalitis (death in 1-10 years)
- MMR vaccine (no antivirals)
