Skin disorders Flashcards
How is the skin in a preterm infant different to a term birth?
The skin is thin, poorly keratinised and lacks subcutaneous fat
How is water loss different in preterm infants to term infants?
Transepidermal water loss is markedly increased and they are unable to sweat
What are congenital pigmented naevi?
Moles involving extensive areas of the skin.
Rare but disfiguring
4-6% lifetime risk of malignant melanoma
Prompt referral to paeds derm and plastics to assess removal
What are the risk factors for malignant melanoma?
Positive FHx Large number of moles Fair skin Repeated episodes of sunburn Living in a hot climate
What is albinism?
A defect in biosynthesis and distribution of melanin.
How does the lack of pigment in the iris, retina, eyelids and eyebrows in albinism affect function?
Failure to develop fixation reflex.
Pendular nystagmus
Photophobia.
The disorder is an important cause of visual impairment
What is eczema?
A genetic deficiency of skin barrier function.
What age does atopic eczema often present?
Usually in the first year of life, but uncommon in the first two months. Exclusive breast-feeding may delay the onset.
When does atopic eczema usually resolve by?
Mainly a disease of childhood.
50% resolved aged 12
75% resolved aged 16
How does eczema often present?
Itching, scratching and exacerbation of the rash.
The excoriated areas become erythematous, weeping and crusted.
Atopic skin is usually dry, and prolonged scratching and rubbing may lead to lichenification (accentuation of the normal skin markings)
What are some causes of exacerbations of eczema?
Bacterial infection Viral infection Ingestion of an allergen Contact with an irritant or allergen Environment: heat, humidity Change or reduction in medication Psychological stress Unexplained
What is a complication of eczema?
Infection
How would you treat eczema?
Avoiding irritants and precipitants Emollients Topical corticosteroids (hydrocortisone) Immunomodulators (tacrolimus) Occlusive bandages (prevent itching, especially at night) Antibiotics or antivirals if infected Dietary elimination Psychosocial support
How would you treat viral warts?
Daily application of proprietary salicylic acid and lactic acid paint or glutaraldehyde.
Cryotherapy with liquid nitrogen
What is ringworm?
Dermatophyte funghi invade dead keratinous structures, such as the horny layer of skin, nails and hair
How do you diagnose ringworm?
Fungal hyphae on skin scrapings
How do you treat ringworm?
Antifungals
What are the symptoms of scabies?
Very itchy burrows, papule an vesicles - distribution varies with age.
Scratching leads to excoriation, secondary eczematous or urticarial reaction often with secondary infection.
How do you treat scabies?
Permethrin cream should be used by the whole family
When does psoriasis normal present?
Not before 2 years
What type of psoriasis is common in children and what does it often preceded by?
Guttate type is most common.
Preceded by strep or viral sore throat or ear infection.
How does psoriasis normally present and for how long?
Lesions are small, raindrop like, round or oval erythematous scaly patches on the trunk and upper limbs.
An attack usually resolves over 3-4 months.
Does psoriasis in children normally recur?
Yes, most get a recurrence within the next 3-5 years
How do you treat psoriasis?
Guttate - bland ointments
What is the cause of acne?
Androgenic stimulation of the sebaceous glands and an increased sebum excretion rate. Obstruction to the flow of sebum in the sebaceous follicle initiates the process of acne
How does acne present and at what age?
1-2 years before puberty.
A variety of lesions, initially open comedones (blackheads) or closed comedones (whiteheads) progressing to papule, pustules, nodules and cysts.
Where does acne usually present?
Lesions occur mainly on the face, back, chest and shoulders
How do you treat acne?
Topical keratolytic agent, benzyl peroxide
Sunshine, in moderation, topical antibiotics or topical retinoids may be helpful.
