dermatology Flashcards
(36 cards)
skin function
Provides an anatomical barrier
Main method of Heat Regulation
Sensory input from the body
Storage for lipids and water
Drug absorbtion and waste excretion
Commensal flora
Normal colonisation that inhibits
pathogens in healthy hosts
Mainly Bacteria and Fungi
Staphylocci and Candida
oily skin
More secretion from sebaceous glands (Sebum)
More bacterial colonisation
Skin becomes heavier & thicker
More risk of pore blockage
More ‘spots & pimples’
Less likely to wrinkle and ageing?
blackheads = comedones
Feature of Acne Vulgaris
Build up of keratin & sebum
Block pores and oxidise giving ‘black’
appearance
furuncles
Infection of skin – pockets filled with pus
Furuncles grouped together are ‘carbuncles’
Folliculitis is furuncle in a hair follicle
Organism “Staphylococcus Aureus”
Red, painful and swollen
Drain pus -
acne
Usually a term for lesions arising from
comedones
papules
pustules
nodules and
inflammatory cysts.
Usually in cosmetically sensitive areas
Follicular sensitivity to testosterone
Increase around puberty
Build up of comedones
Propionibacterium acnes overgrows
and leads to infection & cysts
Scars can form if cysts rupture
Made worse by
Some contraceptive pills (progestogen)
Greasy skin cleansers
Systemic steroid treatment
Some anticonvulsant drugs
Squeezing the spots!
Local management
Reduce excess skin oil
Cleansers – gentle soap
Antibacterial agents
Benzoyl peroxide
Retinoids
Antibiotic lotions
If local treatments fail
Antibiotics
Tetracycline based (minocyclin)
Retinoids
Isotretinoin
Hormone manipulation
Anti-androgens (cyproterone)
erysipelas
Streptoccus pyogenes
Defined sharp raised border
May blister and peel
Usually systemic symptoms
Fever
Rigors
Manage with SYSTEMIC antibiotics
Oral or sometimes IV
Can progress to
Necrotising fasciitis - death of fascial tissues
Septic shock
impetigo
Highly infections skin disease
Staphylococcal or Streptococcal
Crusty red blister appearance
Often associated with Eczema
Treated with topical antibiotics
Sometimes systemic antibiotics
Antibiotic choice found from culture
viral skin infections
Herpes Simplex
Shingles
Molluscum Contagiosum
Warts
Measles
Rubella
Fifth Disease
Roseola
Hand, Foot & Mouth
HIV
Kaposi’s Sarcoma
herpes virus infections
Herpes Simplex
Perioral or Genital
Shingles
Herpes zoster
Roseola
HHV6
Kaposi’s sarcoma
HHV8
herpex simplex
Affect single dermatome or adjacent
dermatomes
Activated by ‘trauma’
Physical, chemical, UV light, ‘run down’
Treat with Aciclovir
herpes zoster
Recurrent’ HZV
Affects SINGLE DERMATOME
Causes SIGNIFICANT pain
Neural inflammation from virus in the nerve
Pain may persist after rash has gone
Post herpetic neuralgia
Treat with HIGH DOSE Aciclovir
mollusc contagiousim
Caused by MCV – a pox virus
Resolve spontaneously in 1-2 years
Usually infants and small children
Clusters of small papules
Warm, moist areas
1-6mm size
More troublesome in children with atopic
eczema
Extensive in adults if HIV infection
warts
Human Papilloma Virus (HPV)
Types 1-3 cause most warts
Types 16 & 18 cause cervical cancer
Contact spread
Treat by
Keratolysis
Cryosurgery
Excision
If Immune competent then most resolve
spontaneously
skin infections
Fungal - dermatophytes
Athlete’s foot (tinea pedis)
Nail infections (onycholysis)
Ringworm
Intertrigo
Pityriasis versicolor
athletes foot
Typically affect feet between toes
groin involvement also common
Usually mixed fungal and bacterial infection
Scaling & sogginess of the skin
Prevent by keeping skin clean dry and damage free
Treat with antifungal/antibacterial cream
miconazole
onycholysis
Nail bed fungal infection
Usually Tinea unguium infection
Nail becomes malformed, thick and
crumbly
May be seen with athlete’s foot
ringworm
Can affect different parts of the body
Groin – tinea cruris
Often spread from feet
Body – tinea corporis
Can be caught from infected animals
Scalp – tinea capitis
Inflammation of scalp leading to hair loss
Mainly in young children
intertrigo
Fungal infection due to chafing in moist
body folds:
Under breasts
Armpits
Inner thighs
Treat with topical
antifungal cream:
Clotrimazole
or Miconazole
pityriasis versicolor
Caused by Pityrosporum orbiculare
Usually a harmless commensal
Also involved in ‘cradle cap’
Excessive growth causes the condition
Results in patchy skin pigmentation
Pale red or brownish
Treat with topical or systemic antifungal
Topical ketoconazole (in wash or shampoo)
Systemic Itraconazole
skin infestations
scabies
lice
scabies
Infection with the ‘Scabies Mite’
Sarcoptes scabiei
From contact with an infected individual
(skin-to-skin)
Occasionally from bedding
Usually 10-12 mites infect the host
3 eggs a day for life of mite – up to 2 months
Burrows appear on the skin
Folds between fingers & on wrists
ITCH is often most troublesome feature
More severe at night
On trunk and limbs
RASH appears on trunk and limbs
Tiny red intensely itchy bumps
May get secondary impetigo
Rash and Itch are ALLERGY and can persist long
after the infestation is gone
Use chemical insecticides – Scabicides
Benzyl benzoate
Permethrin
Malathion
Apply to the WHOLE body from the chin
down including under the nails
Treat ALL close contacts whether obviously
infected or not
lice
Three types
Head
Pubic
Body
Transmitted by close contact with an
infected individual
Transmitted by shared items
Clothing combs, bedding, brushes and toilet
seats!
Head lice most commonly affect
children
Can spread to rest of family though!
Look for ‘nits’ – eggs cemented to the
hair near the scalp
Need to go through hair with a ‘fine
toothed comb’!
NOT hygiene related
Body lice treated by personal and
clothing hygiene
Hot water washing and drying
Chemical Insecticides
Permethrin
Malathion
Phenothrin
inflammatory skin disease
eczema
occupational dermatitis
psoriasis
eczema
Inflammation of the skin
Becomes itchy, dry, flaky
Occasionally weeps
2 main types
atopic & contact
Usually affect FLEXOR surfaces of skin or trunk
