Dermatology Flashcards
Toxic Epidermal Necrolysis - Cause
NSAID, Penicillin, Sulphonamides, Allopurinol, Carbamezapine, Phenytoin
Toxic Epidermal Necrolysis - Presentation
Systemically Unwell
Nikolsky +ve
Affects mucosa
Toxic Epidermal Necrolysis - Treatment
IV Immunoglobulins
Immunosuppresion
At what body coverage is Steven Johnson Syndrome diagnosed?
<10%
At what body percentage is TEN diagnosed?
> 30%
Primary Management of Extensor Psoriasis
Topical Potent Steroid + Topical Vit D for 8 weeks 1x daily
After 4 weeks no improvement -> 4 weeks Vit D 2x daily
Potent Steroid 2x daily or Coal Tar
If the psoriasis is on the face or body how is it treated?
Mild or moderate topical steroid 1/2x daily for two weeks
If the patient has scalp psoriasis how is it treated?
Potent Topical steroid 1x daily
If initial management for scalp psoriasis hasn’t worked what is second line?
Different application method i.e shampoo
+ salicylic acid applied before
Lichen Planus - Signs and Symptoms
Purple Pruritic Papular Polygonal Flat
Triggers for lichen planus flairs.
B blockers Thiazides Penicillamine ACEi Anti malaria's
Seborrhoic Dermatitis - Management
Topical Antifungal - Ketoconazole
Steroids - used in short term
If scalp - Head and Shoulders
Rosacea - Treatment
Mild - Topical Metronidazole
Severe - Oral Oxytetracyline
Flushing - Topical Brimonidine
Telangectasia - Laser therapy
Behcets
Oral + Genital Ulcers + Anterior Uveitis
Erythema Ab Igne
Over exposure to infrared radiation
risk of squamous cell carcinoma
First line Abx for animal/human bite
Co-Amoxiclav
Doxycycline + Metronidazole
Mildy pruritic, hypo pigmented lesion generally
Ptyriasis Versicolour
Topical ketoconazole
Causes of erythema multiform
HSV #
Mycoplasma, streptococcus, penicillin, sulph, carbamezapine, allopurinol, NSAIDs, COCP, SLE, Sarcoidosisi
Abdominal Pain Vomting Motor Neuropathy Depression Hypertension Tachychardia Urine turns RED on standing
Acute Intermittent Porphyria
Autosomal Dominant defect inn porphobilinogen deaminase -> reduce harm synthesis
Management of Acute Intermittent Porphyria
Avoid Triggers + IV Haem Arginate (Haematin)
IV glucose if unavailable
Pemphigus - general description
Nikolsky +ve
Intraepidermal IgG - desmoglein proteins
Affects mucous membranes
Systemic glucocorticoids is mainstay of treatment
Subtypes of Pemphigus and brief description
Vulgaris - Desmoglein III, ulceration and pain
Foliaceous -Desmogein I , Milder than vulgaris, no mucous membrane
IgA - Vesicles and erythematous plaques - occurs on trunk
Paraneoplastic - severe, erosive stomatitis, treat underlying cause, usually
haematogenous cancer
Management of Pemphigus
Systemic corticosteroid -> recurrence = reducing dose + rituximab
Azathioprine or mycophenolate
Plasma exchange in severe acute
Pemphigoid - general description
Nikolsky -ve
No mucous membrane involvement
IgG and compliment deposited subepidermally - along basement membrane
Pemphigoid types
Bullous Pemphigoid
Pemphigus Gestationis
Mucous Membrane
Bullous Pemphigoid
Tense bullae preceded by pruritic plaque
No scarring
Potent topical steroid -> oral if severe - taper dose 2 weeks after last blister
Long term cover - mycophenolate or azathioprine
Non responsive - IV immunoglobulin or rituximab
Mucous membrane pemphigoid
Scarring is real risk
Blindness and airway compromise
Pemphigus Gestationis
Plaques and bullae develop around the umbilicus
Topical -> oral steroids
Delivery is curative
Dermatitis Herpetiformis
IgA deposition within the dermis Papules pustules and vesicles Erosions but no scarring Elbows knees buttocks Stop gluten + Dapson to reduce inflammation and blisters
Linear IgA bullous dermatitis
jewel like IgA deposition along basement membrane
Drug induced - stop Vancomycin Antihypertensives NSAIDs
Idiopathic - dapsone is given
Pityriasis Rosea
Herald spot
Widespread with scale rings
Resolves over 4-6 weeks rarely needs treatment
Oral antihistamines or topical steroid occasionally
Severe - oral acyclovir or phototherapy
Guttate psoriasis
Preceding URTI strep throat
Small red individual spots
May need similar treatment to psoriasis
Impetigo Management
- Hydrogen Peroxide 1%
- Fusidic acid
- Mupirocin if MRSA
- Oral flucloxacillin or erythromycin if pen allergic. For widespread or systemically unwell.
Impetigo - diagnosis and management
Staph Aureus or Strep Pyogenes
Golden crusting
Stay of school until 48 hours of abx or lesions have crusted over
If antibiotics don’t clear swab for sensitivity
Scabies managment
Permethrin is first line
Malathion lotion second line
All household and close contact individuals treated swell
Clean all bedding and clothes
Scabies in an immunosuppressed patient?
Crusted “norwegian” scabies
Invermectin is first line
How long can the itch last post scabies treatment?
4-6 weeks
Excision margins in SCC
If lesion under 20mm = 4mm margin
If lesion over 20mm = 6mm margin
Describe the effect the breslow thickness has on the revision and wide local excision of the melanoma site.
0-1mm = 1cm border 1-2mm = 1-2cm border 2-4mm = 2-3cm border >4mm = 3cm border
At what breslow thickness is a lymph node screen advised?
0.8mm
Can mimic NF
Rapidly growing painful ulcer
Linked to autoimmune diseases - Crohns, AS etc or minor trauma
Pyoderma Gangrenosum
Treat with steroids and immunosuppression NEVER surgical debridement Neutrophil mediated
Bright red raised lump - overgrowth of blood vessels
Can mimic an amelanotic Melanoma
Generally post trauma in diabetic etc
Pyogenic Granuloma
Management of a dermatophyte fungal nail infection.
Oral terbenafine
6 weeks to 3 months for fingernail
3 - 6 months for toe nail
Management of a candida fungal nail
Mild - topical amorolfine
Severe - oral itraconazole 12 weeks
Single rapidly growing lesion up to 1-2 cm
Spontaneoulsy regresses sloughing of tissue
Leaves scar
Smooth dome -> crater with keratin centre
Keratoacanthoma - often precursor to SCC
Requires excision
Black hairy tongue
Brown green or pink - slightly itchy
Poor oral hygiene, recent antibiotics, head or neck irradiation, HIV and IVDU
Tongue scraping required to rule out Candida
NO treatment unless positive for candida
Localised well demarcated hair loss
Broken exclamation mark hairs at border
Linked to autoimmune conditions
Alopecia Areata
50% recover hair within a year
80-90% eventualy
Topical steroids may be helpful
Cellulitis Management
Clinical Diagnosis
Mild - Flucloxacillin or Clarithromycin in Pen allergic ( Erythromycin in pregnant)
Severe - Co Amoxiclav Cefuroxime Clindamycin Ceftriaxone
When do you admit to hospital in cellulitis?
Severe or rapid spread <1yr Facial Cellulitis - unless very mild Frail Immunocompressed Significant Lymphedema
Purple papule or plaque affecting the skin or mucosa
Often ulcerated
Respiratory mucosal involvement leads to haemoptysis
Hx of immunosuppression related diseases
Kaposi Sarcoma - HIV
Human Herpes Virus 8 -
Radiotherapy and resection
Commonest Melanoma
Superficial Spreading - younger - arms legs chest
Other types of less common melanoma
Nodular - 2nd commonest - sun exposed middle aged - lumpy and more aggressive
Lentigo maligna - chronic sunexposed - older
Acral lentigous - palms soles - darker skin types
Management of Tinea
Clinical diagnosis -
Topical Terbanifine -> no improvement skin scraping
Nodules + Pustules + Sinus tracks with rope like scars affecting the intertroginous areas.
Recurrent furuncles and boils
Hidradenitis Supporative
Smoking obesity PCOS and FH all risk factors
Axilla is commonest site
Management of Hidradentis Suppurotiva
Good hygiene loose clothes weight loss and stop smoking
Acute - Steroids (oral or intralesional) or flucloxacillin
- Surgical excision and drainage
Chronic - Topical clindamycin or oral lymecyline
- surgical excision
Type 1 hypersensitivity
IgE mast cell
Anaphylaxis
Atopy
Asthma etc
Type II Hypersensitivity
IgM or IgG binding to cells
Pernicious anaemia, Rheumatic fever, ITP, Autoimmune Haemolytic anaemia
Type III hypersensitivity
Antibody mediated deposition of immune complex
SLE, Post glomerulonephritis, farmers lung, extrinsic allergic alveolitis
Type IV Hypersensitivity
Delayed T cell mediated
Contact allergic dermatitis, Graft versus host, TB, MS, Guilian Barre, Chronic Extrinsic allergic alveolitis
Type V hypersensitivity
Graves or Myasthenia Gravis
Management of hyperhydrosis
Topical Aluminium Chloride
Iontophoresis - gentle electrical stimulation
Botulinum toxin - axilla
transthorasc Sympathectomy
Cellulitis near nose or eyes. What antibiotic is required?
Co-Amoxiclav
Amoxicillin + Clavulanic Acid
Solitary firm papule which dimples on pinching.
Dermatofibroma
Necrotising Ulcerative Gingivitis - Management
Refer to dentist
Meanwhile give Metronidazole oral + Chlorehexidine Mouth wash + analgesia
Lichen Sclerosis - Management
Topical steroid + emollient
Tacrolimus if resistant to steroid
Management of a lipoma
Generally observed unless…
Uncertain of diagnosis or compressing on other structures - removed
When is an USS advised in a suspected lipoma?
Ruling out liposarcoma >5cm Increasing in size Pain Deep anatomical location
Koebners phenomena is common in
Psoriasis - #
Vitiligo
Commonest cause of leg cellulitis
Strep Pyogenes
Junctional Melanocytic naevi
Flat pigmented
Compound melanocytes naevi
Raised pigmented
Intradermal Melanocytic naevi
Raised and pale
Congenital melanocytic naevi
Present at birth
Large and hairy
Dysplastic melanocytic naevi
Atypical can resemble a melanoma
Spitz naevi
Develop in children
Grow rapidly
Pink or red in colour
