Skin Infections Flashcards
What can infect the skin
Bacterial
- Staphylococcus
- Streptococcus
Viral
- Human papillomavirus
- Herpes virus
- Molluscum contagiosum
Yeasts and fungi
Mycobacterial
Treponemal
Parasites
how does the epidermis act as a defence
Epidermis
Physical barrier
- Dry
- Desquamates
Chemical barrier
- Unsaturated fatty acids (oleic acid)
Bacterial interference
- Colonisation by non pathogenic skin flora (microbiome of the skin)
What is the normal skin flora
- Staphylococcus, proprionobacteria, corynebacteria
- Yeasts (malassezia, aspergillus, Cryptococcus)
- Viruses (HPV, EBV, HHV8)
What is the role of the microbiome
Adapted to the sparse nutrients and harsh environment
Produces molecules that inhibit colonisation
Remains stable
Educates the innate and adaptive immune response (Inflammation)
What are clinical examples of superifical infection and colonisation of the skin
Pityriasis versolor (yeast)
Impetiginisation (bacteria)
Intertrigo (candida and fungus)
name two bacterial skin infections
Staphylococcal
streptococcal
name some viral skin infections
Human papillomavirus
Herpes virus
- Simplex
- zoster
Molluscum contagiosum
What is a yeast
- unicellular forms replicated by budding
what is Candida albicans
- commensal of mouth and GI tract; opportunistic infection
what is pityriasis versicolor
overgrowth of commensal yeast, young adults, brown/pink scaly patches, hypopigment if suntan
What is dermatophytes
multicellular filaments or hyphae that reporduce by spore formation
What is tinea
- denote fungal skin infection with st. corner hair or nails
name an example of parasites
scabies
name some unusual skin infections
Tuberculosis
Leprosy
Leishmania
Tick borne diseases
what must you not miss in investigating the skin
Skin signs of systemic infections
cutaneous necrosis associated with disseminated intravascular coagulation in sepsis
Toxic epidermal necrolysis and staphylococal scalded skin syndrome
Necrotitising fasciitis (a synergistic bacterial skin infection )
