ch 16 objectives Flashcards
Describe the important anatomical features of the skin
Three layers: epidermis (waterproof barrier), dermis (structure & sweat glands), hypodermis (insulation).
List characteristics of the skin’s normal microbiota.
Diverse microbes (bacteria, fungi) vary by location.
Mostly commensals, aiding in defense and function.
List the natural defenses present in the skin
Physical & chemical barriers (sebum, acidity).
Immune cells & beneficial microbiota.
Shedding dead skin cells removes pathogens
staphylococcus aureus skin infections (epidemiology, virulence, disease presentation, diagnosis/testing, treatment, prevention)
Ep: transmitted through direct and droplet contact
Vi: exfoliative toxins A and B
Pres: infections are suppurative (pus producing), cause furnucles, carbuncles,
Diag: though clinical signs and symptoms
trea: treated with oral and intravenous antibiotics depending on level of infections
Prev:
carbuncle vs impetigo, vs cellulitus
carbuncle: Deep abscesses that can spread from furuncles
impetigo: Bullous type (>5 mm blisters), primarily found in neonates/children, occurs around the mouth, is contagious and is from an exotoxin
cellulitis: Infection of connective tissue
measles
causative agent: virus
epidemiology: transmitted by respiratory droplets, infects tracheal and bronchial cells (infectious during incubation, prodrome phase and skin rash)
presentation: sore throat, oral lesions–> kopliks spots, red bumps that erupt on head and move towards trunk and extremities
prevention/treatment: MMR vaccine
rubella
causative agent: rubivirus
epidemiology: contact with respiratory secretions, congenitally to infants (infectious during prodromal phase and rash)
presentation: minor rash (babies), joint inflammation (adults)
prevention/treatment: rubella vaccine
fifth disease
causative agent: parovirus B1
epidemiology: extremely contagious/ droplet and direct contact
presentation: slapped cheek rash that then spreads around body
prevention/treatment: no vaccine or treatment
rosela
causative agent: human herpesvirus 6
epidemiology: infected during adulthood
presentation: usually not accompanied by rash stage, high fever that can result in seizures, rash stage follows
prevention/treatment: no vaccine or treatment
impetigo
causative agent: exfoliative toxins A and B (staph aur) or streptococcus pyogenes
modes of transmission: direct and indirect contact
presentation: skin flakes/peels and scabs (typically found around mouth face and extremities)
prevention/treatment: hygiene practices, topical mupirocin in serious
cellulitis
causative agent: streptococcus pyogenes in healthy, any bacteria and some fungi in immunocompromised, group b strepticocci for infants
modes of transmission:
presentation: pain/tenderness, fever, lymphangitis (red lines leading away from area
prevention/treatment:oral antibiotics, intravenous antibiotics for immuno, and surgical debridement with tissue is damages
chicken pox
causative agent: human herpesvirus (varicella
modes of transmission: respiratory droplets
presentation: rashes/lesions in the center of the body
prevention/treatment: live attentuated vaccine and antibiotics if bacterial
small pox
causative agent: variola virus
modes of transmission: droplets and fomites (contaminated bedding/clothing)
presentation: deep lesions distributed on extremities
prevention/treatment: live virus vaccine, drugs including tercovirimat and cidofovir
leishmaniasis
causative agent: parasites –> L. tropica and L. brasiliensis
modes of transmission: female sand flies
presentation: localized infection of capillaries of the skin
prevention/treatment: no vaccine, must avoid sand flies
cutaneous anthrax
causative agent: bacteria (bacillus antracis)
modes of transmission: direct contact with endospores through cuts and abrasions
presentation: papule that becomes necrotic and ruptures to form black eschar
prevention/treatment: avoid contact, vaccine exists but not commonly used
