Dermatology Flashcards
Causes os eczema
mixture of genetic and environmental triggers.
-irritnks, skin infections, stress, contact allergens, extremes in temperature, inhaled allergens, FH of atopy.
Breastfeeding is protective.
Presentation of eczema in infants and in children
infants: erythematous scaly weeping lesions, usually on the face, neck, trunk and wrists (known as cradle cap)
children: dry and thickened skin, with scaling hyperpigmentation in flexor surfaces.
what is eczema herpeticum? how is it managed?
HSV 1 infection superimposed on top of atopic eczema.
blistering, pustular, systemic illness with fever and lymphadenopathy. Very infectious.
Will need IV flucloxacillin and IV acyclovir
Complications of eczema to look out for?
bacterial skin infections - crusting, surrounding cellulitis
Eczema herpeticum - systemic illness as will as infectious rash.
Diagnosis of eczema
itchy skin plus three of the following:
- itchy skin folds
- history of asthma or hayfever
- dry skin
- visual flexural eczema
- onset in first two years of life
Management of eczema
Parental advice: regular emollients, avoid triggers, look for signs of bacterial infections, 60% of children will recover by teens, keen nails short to avoid scratching.
- Emollient - substitute for soaps, regular use as moisturiser
- Topical steroid cream for flare ups - start with 1% hydrocortisone then step up, most potent is beclomethasone or dermoid cream.
- Antihistamines to stop scratching
- Topical calcineurin inhibitors (tacrilimus) can be used if unresponsive to steroids
What is impetigo? how common is it and what are the risk factors?
highly contagious ‘honeycomb crust’ bacterial infection, most common skin infection in children, more common in areas of poor hygiene and overcrowding.
Causes of impetigo?
staph aureus
other causes: strep pyogens or group B heamolytic strep
complications of impetigo?
if due to strep can have scarlet fever or glomerulonephritis.
bullous impetigo is common neonates if due to staph aureus
Presentation of impetigo
itchy rash with blisters, developing into a honeycomb crust, usually around the face and mouth.
if bullous disease - can have malaise, blisters rupturing, can occur on top of eczema
Management of impetigo
skin swab for culture and sensitivity.
isolation until infection resolves or been on antibiotics for 48hrs.
topical abx - fusidic acid
oral abx - flucloxacillin
good hygine, bathe only using water, usually resolves rapidly.
how common is nappy rash? what are the risk factors?
25% of infants, usually due to contact dermatitis.
more common if using baby wipes, skin cleaning regimines, recent diarrhoea or abx use, PTB.
causes of nappy rash
overhydration of the skin causing friction, prolonged contact with nappy and chemicals, results in a rash.
Ammonia is released by bacterial breakdown of urine which can be an irritant.
presentation of nappy rash (contact dermatitis)
eryethema and papules over areas of contact, with SPARING of the creases and gluteal cleft.
presentation of nappy rash complicated by candida infection
erythema, well defines rash, no sparing of skin folds, may have satellite lesions eg oral candida.
Treatment for nappy rash: contact dermatitis or candia infection
contact dermatitis -conservative management - can use prophylactic barrier cream.
candida - topical antifungals - miconazole gel or nystatin suspension.
Important to explain to parents it is not a sign or poor care - some babies have sensitive skin! use high absorbency nappies, fragrance free, change quickly, avoid irritant soaps and bubble baths.
What is stevens johnsons syndrome?
Detactchemnet of basement membrane of the skin, causing severe dehydration and increasing exposure to further infection effecting skin and mucous membranes, genitals and eyes.
It is immune medicated type 4 hypersensitivity disorder, which can present as a spectrum, from SJS to Toxic epidermal necrolysis.
what is the difference between SJS and TEN (stevens j and toxic epidermal necrolysis?)
- If 10% of the body is effected - SJS
* If over 30% of the body is effected - TEN
Causes of Steven Johnsons syndrome
adverse reactions to medications or viral infections
Medications: carbamazepine, sulphonamides, antivirals, phenytoin, lamotrigine, salicaytes, sertraline, NSAIDS< antifungals, allopurinol.
Infections: HSV, EBV, CMV, enterovirus, cocksakie, influenza, mumps, typhoid.
Presentation of SJS
Prodrome - viral illness, cough, fever
sudden rash - non itchy, palms and soles and extensor surfaces moving to trunk. Wide spreads blisters and erythematous skin. Mayalgia, arthalgia, cough.
OE: fever, tachycardic, hypotenion, altered GCS.
Management of SJS
A-E approach
identify and remove causative agent.
supportive therapy: fluids, emollient creams, systemic steroids and antihistamines
Complications of SJS
- Life threatening condition
- can cause permanent damage to eye sight
- can progress to TEN if more than 30% of the body is effected.
What is erythema nodosum?
hypersensitivity reaction, inflammation of fat cells under the skin resulting in tender red nodules.
caused of erythema nodosum?
hypersensitivity due to infection, medication, systemic disease, or idiopathic
