10- Paediatric Dermatology 2/2 Flashcards
There are a few specific signs suggestive of psoriasis:
- Auspitz sign refers to small points of bleeding when plaques are scraped off
- Koebner phenomenon refers to the development of psoriatic lesions to areas of skin affected by trauma
- Residual pigmentation of the skin after the lesions resolve
acne vulgaris background
- Very common condition
- Acne – comedowns
- Open comedowns- blackheads
- Closed comedowns- whiteheads
Pathophysiology of acne vulgaris
- Caused by chronic inflammation, with or without localised infection, in pockets of skin known as pilosebaceous unit
- Acne results from increased production of sebum, trapping keratin and blocking the pilosebaceous unit
- Leads to swelling and inflammation
- Androgenic hormones increase production of sebum- therefore exacerbated by puberty and improves with anti-androgenic hormonal contraception
- Bacteria: Propionibacterium acnes – bacteria which colonises the skin and can contribute to acne
RF for acne
- Puberty and adolescence
- Family history
Presentation of acne
- Significant variation in every of acne
- Red, inflamed and sore spots on the skin
- Typically distributed
o Face
o Upper chest
o Upper back
Management of acne
Stepwise
- No treatment if mild
- Psychosocial counselling
- Topical benzoyl peroxide
- Topical retinoids (chemicals related to vitamin A)- slows production of sebum
- Topical antibiotics – clindamycin (prescribed with benzoyl peroxide to reduce bacterial resistance)
- Oral antibiotics such as lymecycline (make sure not pregnant- tetracycline is a teratogen)
- Oral contraceptive pill e.g. Co-cyprindiol (Dianette)- COCP
- Oral retinoids e.g. isotretinoin
Oral retinoids
Isotretinoin i.e. Roaccutane
- Effective last line option
- Prescribed by specialist
- Highly teratogenic
- Women must have reliable contraception and do regular pregnancy tests
o And agree to termination if gets pregnant
o Stop a month before trying to get pregnant
MOA of roaccutane
- Reduce production of sebum, reducing inflammation and bacterial growth
side effects of oral retinoids
- Dry skin and lips
- Photosensitivity of the skin to sunlight
- Depression, anxiety, aggression and suicidal ideation. Patients should be screened for mental health issues prior to starting treatment.
- Rarely Stevens-Johnson syndrome and toxic epidermal necrolysis
Describing lesions: Acne
- Pustules are small lumps containing yellow pus
- Comedomes are skin coloured papules representing blocked pilosebaceous units
- Blackheads are open comedones with black pigmentation in the centre
- Ice pick scars are small indentations in the skin that remain after acne lesions heal
- Hypertrophic scars are small lumps in the skin that remain after acne lesions heal
- Rolling scars are irregular wave-like irregularities of the skin that remain after acne lesions heal
impetigo background
Very contagious superficial bacterial infection
Classified as
- Non-bullous
- Bullous
–> Epidermolytic toxins released by S.aureus break down proteins that hold skin cells together
–>This causes fluid filled vesicles
impetigo pathophysiology
Causative organism
- Usually Staphylococcus aureus
- Streptococcus pyogenes
Occurs when bacteria enter via a break in the skin
- Can be otherwise healthy skin
- Or related to eczema or dermatitis
presentation of impetigo
- Golden crust
1) Non-bullous impetigo
- Around nose or mouth
- ‘golden crust’
- Unsightly
- No systemic symptoms of illness
2) Bullous
- More common in neonates and children <2
- Always causes by staphylococcus aureus
- Fluid filled vesicles which grow in size and bursh, forming a “golden crust:
- Heal without scaring
- Can be painful and itchy
- Systemic symptoms
- Severe infection called : staphylococcus scalded skin syndrome
RF for impetigo
- Age. Impetigo occurs most commonly in children ages 2 to 5.
- Close contact. Impetigo spreads easily within families, in crowded settings, such as schools and child care facilities, and from participating in sports that involve skin-to-skin contact.
- Warm, humid weather. Impetigo infections are more common in warm, humid weather.
- Broken skin. The bacteria that cause impetigo often enter the skin through a small cut, insect bite or rash.
- Other health conditions. Children with other skin conditions, such as atopic dermatitis (eczema), are more likely to develop impetigo. Older adults, people with diabetes or people with a weakened immune system are also more likely to get it.
Stopping the spread: impetigo
Impetigo is very contagious so children should be kept off school during infection
- Until lesions have healws or had antibiotics for >48 hours
Advice for patient
- to not scratch or touch lesions
- hand hygiene
- avoid sharing face towels and cutlery
presentation of contact dermatitis
- Shows up on skin after direct contact e.g. face, hands, feet, arms, legs
- When allergen is removed, rash slowly resolves over several days to several weeks and will reappear with further contact
- Always itchy
- Erythematous blisters
- Oedema
- Dryness
- Fissuring
- Lichenification
- Pigmentation increase or decrease
presentation of warts/ HPV
- Cutaneous viral wards are hard due to their keratinous surface
- Tiny red or black dots can be visible in the wart are papillary capillaries
