Dermatology Flashcards
Give three red flags for a chronic rash
Skin Pain
Mucous Membrane Involvement
Unwell Child
Give three causes of a clear fluid filled rash
HSV
Impetigo
Chickenpox
Give three causes of a pus filled rash
Acne
Folliculitis
Pustular Psoriasis
Give three causes of a raised rash
Urticaria
Viral Warts
Milia
Give three causes of a red and scaly rash without epidermal breakage
Psoriasis
Tinea
Sebhorreic Dermatitis
Give a cause of a red and scaly rash with epidermal breakage
Atopic Eczema
Give three differentials for a purpuric rash (non blanching)
Meningococcal Septicaemia
ITP
Leukaemia
Define Acne Vulgaris. What is the cause?
Inflammatory disease of Pilosebaceous Follicles
Under influence of androgens, sebaceous glands produce more sebum and subsequently get blocked
Can become colonised with bacteria - Propionibacterium Acne
Acne Vulgaris commonly affects face/chest/upper back. How does it present?
Non Inflammatory (open and closed comedones - black and white heads
Inflammatory (Papules, Postules, Nodules, Cysts)
If Acne is localised then topical therapy can be used. Describe the three different types
Benzoyl Peroxide - reduces sebum production and P.Acne growth (may cause skin to peel)
Topical Antibiotics - used in combination with another topical therapy, erythromycin/Tetracycline
Topical Retinoids - Anti Inflammatory effect, contraindicated in pregnancy
If Acne is diffuse then systemic therapy can be used. Describe the three different types
Doxycycline (if over 12 - photosensitivity and oesophagitis)
Anti Androgens - COCP
Oral Isotretinoin - Highly effective but toxic so given under consultant supervision
How long does Systemic Acne Therapy take to ‘work’ in theory
Allow 3-4 months before review
How can Acne scarring be treated?
Laser Resurfacing
Chemical Peels
Define Eczema/Atopic Dermatitis
Chronic atopic condition caused by genetic defect in skin barrier function (loss of variants of filaggrin)
Describe the pathophysiology of Eczema
Tiny gaps in skin barrier provide entrance for irritants/allergens/microbes , that create an immune response resulting in inflammation
Name three exacerbating factors for Eczema
Infections
Allergens
Sweating
How does Eczema typically present?
Itchy erythematous dry scaly patches
Infants - Face and Extensor
Children and Adults - Flexor
Nail pitting and ridging
How do Eczema exacerbations present?
Erythematous, Vesicular, Weepy
What is the maintenance therapy for Eczema?
Emollients (thick layers, should be used as soap substitutes)
Can be thin - E45, Diprobase
Or thick - Hydromol, Cetraben
How are Eczema flares treated?
Thicker emollients, Topical Steroids, Wet Wraps
The use of steroids should be the weakest possible for the shortest possible time. Describe the steroid ladder
Mild (Hydrocortisone)
Moderate (Eumovate - Clobetasone Diproprionate)
Potent (Betnovate)
Very Potent (Dermovate)
Describe some specialist treatment in resistant eczema
Zinc bandages
Topical Tacrolimus
Phototherapy
State three possible infective organisms in Eczema
S.Aureus
Eczema Herpeticum
Molluscum Contagiosum
What is Napkin Dermatitis/Nappy Rash?
Common due to urine/faeces/friction in the nappy area
Spares the folds and favours the convexities
When would you suspect Candida infection in Nappy Rash?
If there are satellite lesions
How is Nappy Rash managed?
Frequent nappy changes
Drying after bathing
Hydrocortisone Ointment
If Nappy Rash fails to respond to initial management, what other diagnoses could be considered?
Psoriasis
Zinc Deficiency
Langerhans Cell Histiocytosis
Give five causes of Pruritus Ani in infants
Contact dermatitis from faeces/urine/sweat Allergic Contact Dermatitis Threadworms Anal Disease (eg Crohns) Candidiasis
How should Pruritus Ani be investigated?
Threadworms are normally visible
Swans of Perianal Skin for MC&S
How should Pruritus Ani be managed?
Treat underlying cause
Improve Perianal Hygiene
Mild Steroid Ointment (if infective causes ruled out)
Give three causes of Pruritus Vulvae
Contact Dermatitis
Diabetes Mellitus
Threadworms
How should Pruritus Vulvae be managed?
Ensure no evidence of lichen sclerosus or diabetes
Void regularly
Change damp underwear
Wipe front to back
Treat acute inflammation with topical steroid until redness settles
Give three common allergens in Allergic Contact Dermatitis (delayed type IV hypersensitivity)
Nickel
Plasters
Henna Tattoos
How is Allergic Contact Dermatitis investigated and managed?
Ix - Patch test left on for 48hrs and then read on day 5 to 7
Mx - Allergen withdrawal and topical steroids
What is Perioral Lip Lick?
Eczema around mouth
Common in mouth breathers
How is Perioral Lip Lick managed?
Frequent lip balms
Topical steroids
Reduce irritant foods for 2-3 weeks (acidic, vinegar, tomato based)
Cutaneous warts are caused by cutaneous infection with HPV. How does it present?
Painless form papules with rough hyperkeratoic surface
Typically affects hands/knees/face/feet
Normally resolves within 3 years
Cutaneous warts normally don’t require management. If they are painful, or causing psychosocial problems, how can they be managed?
Destructive techniques - Keratolytic with Salicyclic, Liquid Nitrogen Cryotherapy, Podophyllotoxin
Immune Based - Immunotherapy
What is Impetigo?
Superficial bacterial skin infection caused by S.Aureus and less commonly S.Pyogenes characterised by Golden Crust
Describe the pathophysiology of Impetigo
When bacteria enter via a break in the skin (may be healthy or may be related to dermatitis)
Contagious so children should be kept home from school
Impetigo can be Bullous or Non Bullous. How does Non Bullous Impetigo present?
Typically occurs around nose and mouth
Exudate dries to form golden crust - unsightly but not unwell
How is Non Bullous Impetigo managed?
Localised - Topical Fusidic Acid/Hydrogen Peroxide
Widespread - Oral Flucloxacillin
Don’t touch lesions, remain off school until healed/48h of Anitbiotics
Impetigo can be Bullous or Non Bullous. How does Bullous Impetigo present?
Staphylococcus Aureus produces epidermolytic toxins, breaking down skins structural proteins, causing fluid filled vesicles
Vesicles grow and burst to form golden crust - painful and itchy
May have systemic symptoms
If widespread -Staphylococcal Scalded Syndrome
Which form of Impetigo is more common in under 2s?
Bullous
How is Bullous Impetigo managed?
Flucloxacillin (may require IV if severely unwell)
Give three complications of Impetigo
Cellulitis
Sepsis
Post Strep GN
Define Psoriasis and state the four main subtypes
Chronic autoimmune condition that causes symptoms of recurrent psoriatic lesions
Plaque, Guttate, Pustular, Erythrodermic
How does Chronic Plaque Psoriasis present?
Thickened erythematous scabs that can be on extensor surfaces and scalp
1-10cm
More common in adults
How does Guttate Psoriasis present?
Note: Most common form in children
Small raised papules across trunk and limbs that are mildly erythematous and scaly
Often triggered by Streptococcal throat infections, stress or drugs
Resolves within 3-4 months
How does Pustular Psoriasis present?
Pustules form under areas of erythematous skin
Can be systemically unwell and initially require hospital admission
How does Erythrodermic Psoriasis present?
Severe extensive erythematous areas covering most of skins surface
Raw exposed areas
Medical emergency and admission
Give three clinical features OE of Psoriasis
Auspitz Sign - small points of bleeding when plaques are scraped
Koebner Sign - development of lesions where skin has previously been affected by trauma
Residual pigmentation after resolution
Name five nail changes in Psoriasis
Pitting Thickening Discolouration Ridging Oncholysis
Name three management options for Psoriasis
Topical (Steroids, Vit D Analogue - Calcipitriol)
UVB Phototherapy
Severe - Systemic Methotrexate/Ciclosporin
Eczema Herpeticum is a viral skin infection. Describe the pathophysiology
Usually infection with HSV1, but can be with VZV
Normally occurs in a patient with pre-existing skin conditions
Associated with cold sore in patient or close contact
How does Eczema Herpeticum typically present?
Patient who already suffers eczema presenting with widespread, painful vesicular rash (containing pus)
May have systemic symptoms such as fever/lethargy/irritable
After the vesicular rash bursts - small punched out ulcers with red base
Eczema Herpeticum is normally a clinical diagnosis. How is it managed?
Aciclovir (oral or IV depending on severity)
Note: very dangerous in those who are immunocompromised
Define Erythema Multiforme
Erythematous rash caused by hypersensitivity reaction
Caused by viral infection (especially HSV), Mycoplasma Pneumoniae, Drugs (NSAIDs, Penicillins)
How does Erythema Multiforme present?
May or may not have preceding URTI/Fever/Flu
Widespread itchy rash, characterised by target lesions
Doesn’t normally affect mucous membranes
Erythema Multiforme is a clinical diagnosis. How is it managed?
Treat any underlying cause
Often mild and resolves spontaneously in 1-4 weeks
If severe - Fluids, Analgesia and Steroids
Molluscum Contagiosum is a viral skin infection. How does it present?
Small flesh coloured papules with a characteristic control papule
Spread through direct contact/sharing towels or bedding
How is Molluscum Contagiosum managed?
Normally self resolves within 18 months
Avoid sharing towels and scratching
Any signs of bacterial superinfection - topical fusidic
If immunocompromised/in problem area - Benzoyl Peroxide/Cryotherapy
Define Pityriasis Rosea
Generalised self limiting rash often occurring in adolescents and young adults. May be caused by HHV6 or HHV7
How does Pityriasis Rosea present?
May have a prodrome (headache, tiredness, flu)
Herald patch (Red/Pink scaly oval lesion, around 2cm on torso) Becomes widespread in ‘Christmas Tree Fashion’ along ribs
In darker skin tones it will appear grey
How is Pityriasis Rosea treated?
Normally resolves without treatment in 3 months
Can cause skin discolouration which will resolves within another 3 months
Not contagious
What is Seborrhoeic Dermatitis?
Inflammatory condition of sebaceous glands
Affects scalp/nasiolabial folds/eyebrows
Malassezia yeast plays a role
How does Infantile Seborrhoeic Dermatitis present?
AKA Cradle Cap
Crusty flakey scalp, normally resolving by four months
How is Infantile Seborrhoeic Dermatitis (AKA Cradle Cap) treated?
Brush scalp with oil then wash off
White petroleum jelly overnight
If fails - topical anti fungal such as Clomitrazole for 4 weeks
Seborrhoeic Dermatitis of scalp most commonly occurs in adolescents and young adults, how is it managed?
Ketoconazole shampoo left on for five minutes
Often recurs after successful treatment
How is Seborrhoeic Dermatitis of Face and body managed?
4 weeks Clotrimazole
Localised inflammation can be treated with Hydrocortisone
What is Ringworm?
Fungal infection of the skin also known as tinea/dermatophytosis
Can be subdivided into: Capitis, Pedis, Cruris, Corporis, Onchomycosis
How does Ringworm present?
Itchy rash that is erythematous, scaly and well demarcated
Edge of ring is more prominent in colour
How does Tinea Capitis present specifically?
Well demarcated hair loss
Scalp Dryness
How does Tinea Pedis present specifically?
White/Red/Flaky itchy patches between toes
More likely if feet are sweaty and damp for long periods
How does Onchomycosis present specifically?
Thickened discoloured nail
Ringworm is normally a clinical diagnosis, describe the different antifungal medications options
Topical Clomtrimazole
Ketoconazole Shampoo
Oral Fluconazole/Itraconazole
How is Onchomycosis treated?
Amorolfine Nail Lacquer
If resistant then Oral Terbinafine
Daktacort is also a management option for Ringworm. What is contained within it?
Miconazole
Hydrocortisone
What is Tinea Incognito?
Extensive but less well recognised infection due to steroid use (eg mistakenly diagnosed as dermatitis)
What is Erythema Nodosum?
Red lumps that appear across patients shins due to inflammation of subcutaneous fat (hypersensitivity reaction)
Name five associations with Erythema Nodosum
Strep Throat TB Lymphoma NSAIDs IBD
What is Staphylococcal Scalded Syndrome?
Condition caused by a type of S.Aureus that produces epidermolytic toxins (proteases that break down skin) usually affecting children <5y
How does Staphylococcal Scalded Syndrome present?
Intitially generalised erythema patches, skin then wrinkles, and then bullae form
When bullae burst it looks like a scald/burn
Systemic symptoms
What is Nikolsky sign in Staphylococcal Scalded Syndrome?
Rubbing of skin causes it to peel away
How is Staphylococcal Scalded Syndrome managed?
IV antibiotics
Fluids
