Dermatology Flashcards
1
Q
How does acne present?
A
- Mild – mostly non-inflamed lesions (open + closed comedones) with a few inflammatory lesions.
- Moderate – more widespread, with increased number of inflammatory papules and pustules.
- Severe – widespread inflammatory papules, pustules, nodules, and cysts. Scarring may be present.
- Conglobate acne – rare, severe, most often affects M. extensive inflammatory papules, suppurative nodules (may coalesce to form sinuses), and cysts on trunk and upper limbs.
- Acne fulminans – sudden, severe inflammatory reaction – deep ulcerations and erosions, may be systemic effects (hospital admission and oral steroids)
2
Q
How do you manage acne?
A
- Tretoin topical (topical retinoid) + topical ABx (erythromycin)
- Topical benzoyl peroxide
- Topical azelaic acid
- Conservative – avoid overcleaning the skin, not caused by poor hygiene. Don’t pick/ squeeze, maintain healthy diet.
- Mild – topical therapies: Benzoyl peroxide (may bleach clothes), salicylic acid, topical antibiotics (clindamycin), topical retinoids (adapalene)
- Moderate – severe: oral abx (doxycycline, lymecycline) change after 3 months if no response.
- COCP (dianette) can be used in conjunction (anti-androgen)
- Oral retinoids e.g. Isotretinoin may be prescribed when referred to dermatological specialist (SEs, and monitoring)
- Monitoring: lipid panel, LFTs, women – montly pregnancy tests.
- SEs: highly teratogenic, dry lips, cheilitis, dry skin, fragile skin, photosensitivity, temporary hair loss, brittle nails, myalgia, depression, abnormal LFTs.
- Advice: shave instead of wax, emollients, drink minimal alcohol, pregnancy prevention programme for women of childbearing age (2x reliable forms of contraception), daily spf.
- Scarring – laser resurfacing, dermabrasion, chemical peels.
3
Q
What is eczema?
A
- Eczema is an inflammatory skin condition where patches of skin become inflamed, itchy, red, and cracked. Most common form is ‘atopic eczema’.
- Atopic eczema is a chronic, itchy, inflammatory skin condition presenting most frequently in childhood.
4
Q
What are some RFs of eczema?
A
filaggrin gene mutation (impairs barrier function of the skin), age <5y, FH, allergic rhinitis, asthma, active/ passive smoking.
5
Q
How does eczema present?
A
- Itchy erythematous, dry scaly patches.
- More common on face and extensor aspects in infants, but on flexors in children and adults.
- Acute lesions are erythematous, vesicular, and exudative.
- Chronic scratching can lead to excoriations and lichenification (thickened and leathery)
6
Q
How is eczema managed?
A
- Emollients, bandages, soap substitutes
- Acute flare – topical corticosteroids such as hydrocortisone
- Hydrocortisone → eumovate →Betnovate → dermovate
- Tacrolimus – good steroid sparing agent
- Intermittent tropical corticosteroids: hydrocortisone/ desonide
- If severe itch or urticaria – non-sedating antihistamine (cetirizine, fexofenadine)
- Antibiotics for secondary bacterial infection – flucloxacillin
- Immunosuppressants (prednisolone, azathioprine, ciclosporin) for severe, non-responsive cases.
7
Q
What is the classification of urticaria?
A
- Acute <6wks
- Chronic >6wks
- Spontaneous (chronic) no identifiable cause
- Autoimmune IgG autoantibodies to IgE receptors
- Inducible (chronic) response to physical stimulus (temperature, pressure, UV)
8
Q
How is urticaria managed?
A
- Conservative: Avoidance of triggers, topical anti puritic agents e.g. calamine to relieve the itch. Chronic - QoL questionnaire
- 1st: Non-sedating anti-histamine e.g. cetirizine for <6wks:Increase to <4x standard
- 2nd: Severe – short course of oral corticosteroids (prednisolone 40mg OD for 7d)
9
Q
What is contact dermatitis and how does it present?
A
-
Irritant – non-immunological inflammatory reaction caused by direct physical/ toxic effects of a irritating substance on the skin (acute/chronic)
- Common irritants: water, sweating, detergents, solvents, powders, dust, soil
-
Allergic – type IV (delayed) hypersensitivity reaction after sensitiation and re-exposure to an allergen.
- Common allergens: personal care products, metals (nickel, Cu), topical medications (corticosteroids), plants
- Presentation: itching, burning, swelling, erythema, scaling, rash. Often seen on the hands (response to jewellery)
10
Q
How do you manage contact dermatitis?
A
- Conservative: stimulus avoidance (may take 8-12 weeks to see improvement), use gloves etc if cant avoid stimulus.
- Topical corticosteroids (as can be hard to distinguish allergic, from irritant)
- Dermatology referral if severe, chronic, recurrent or persistent.
11
Q
What is psoriasis?
A
- Chronic inflammatory skin condition characterised by erythematous, inflamed, silvery white scaly plaques and circumsribed papules and plaques.
- These often affect the elbows, knees, extensor limbs and scalp
- It can cause itching, irritating, burning and stinging
12
Q
What are the diff types of psoriasis?
A
- Chronic plaque psoriasis – most common, well demarcated erythematous, scaly plaques, scalp and extensor regions.
- Generalized pustular psoriasis – palms and soles, tender, red skin with small white elevations of pus
- Guttate psoriasis – triggered by strep infection in childhood, small, red, discrete ‘teardrop’ spots over the trunk and limbs.
- Flexural psoriasis – occurs within skin folds, smooth and shiny red lesions.
- Erythrodermic psoriasis – total body redness, fire red scales, extremely itchy and painful, scales fall off in sheets
- Psoriatic arthritis
13
Q
A
HIV/ AIDS, alcohol, strep infection, UV light exposure, pscyhological stress, trauma, drugs (lithium, anti-malarials, beta blockers, NSAIDs, ACEi)
14
Q
How is psoriasis managed?
A
- Immediate same day dermatology referral and assessment for generalized pustular psoriasis, or erythrodermic psoriasis
- Creams, lotions, gels, emollients for widespread psoriasis. Ointments for thick scale
- 1st: Mild topical corticosteroid (hydrocortisone) + Vitamin D (Dovobet gel and ointment)
- 2nd: Phototherapy: Narrow band UVB + methotrexate + ciclosporin, retinoids (acitretin)
- Biologics: infilixumab, apremilast + acicretin (oral retinoid)
15
Q
What is cellulitis?
A
Acute spreading infectin of the skin with visually indistinct borders that principally involve the dermis and subcut tissue
16
Q
How is cellulitis ixd, mxd?
A
Ix: usually clinical, WCC, ESR, skin swab + culture, skin biopsy, USS (for abscess)
Mx:
- Conservative: (pain relief, fluids), sterile dressings, elevate leg, compression stockings
- High dose flucloxacillin (+/- BenPen if rapid deterioration)
- Admit if à limb/life threatening (Class ¾), rapid deterioration, frail, facial cellulitis, orbital/periorbital cellulitis
- IV abx – vancomycin
17
Q
What are maligant melanomas?
A
- Overview: invasive malignant tumour of the epidermal melanocytes with the potential to metastasize.
- Most common cause of skin cancer related deaths.
- Risk factors: age, prev BCC/ SCC, XS UV exposure, skin type I, many or atypical moles, FH
- Pathophysiology
- Normal melanocytes found in the stratum basal
- Non-cancerous growth of melanocytes results in moles (benign melanocytic naevi) and freckles.
- Cancerous growth results in melanoma
- In situ if confined to epidermis
- Invasive if spread into dermis
- Metastatic if spread to other tissues)
18
Q
What are the diff types of malignant melanoma?
A
19
Q
How are malignant melanomas classified?
A
- ABCDEF (evolving)
-
Glasgow 7-point checklist
- Major – change in size, irregular shape, irregular colour
- Minor – diameter >7mm, inflammation, oozing, change in sensation
- Breslow thickness (see pic)
20
Q
What Ix are used for malignant melanoma?
A
- Diagnostic excision, calculate Breslow score / Clark’s level
- Breslow score measured in vertical mm from the base of the granular layer to the deepest point of tumour involvement
- TNM staging – sentinel lymph node biopsy, PET-CT
21
Q
How are malignant melanomas treated?
A
Surgical excision (wider excision margin up to 3cm) to ensure complete removal (SLNB)
+/- chemo for metastatic disease
Immunotherapy (iplimumab/ pembrolizumab) if widespread mets
22
Q
What are superficial spreading melanomas? How are they managed?
A
- Grow slowly and metastasize later on
- They have a better prognosis than nodular melanomas which invade deeply and metastasize early
- Management: Chemo - ipililumab
23
Q
What is the ABCDE criterias for the diagnosis of melanoma?
A
- Assymetry
- Border - irregular
- Colour - non uniform
- Diametes - 7mm
- Elevation
24
Q
What is a squamous cell caner of the skin?
A
- Overview: locally invasive malignant tumour of the epidermal keratinocytes, which has the potential to metastasize.
- Generally arises within an actinic keratosis, or Bowens disease.
- Ulcerated, crusted, firm irregular lesions on sun exposed sites
- Presentation: keratotic (scaly, crusty), ill-defined nodule which may ulcerate (common on lip due to smoking)
25
Q
What are some RFs for SCC?
A
- excessive exposure to sunlight / psoralen UVA therapy
- actinic keratoses and Bowen’s disease
- immunosuppression e.g. following renal transplant, HIV
- smoking
- long-standing leg ulcers (Marjolin’s ulcer)
- genetic conditions e.g. xeroderma pigmentosum, oculocutaneous albinism
- HPV
26
Q
How are squamous cell cancers of the skin managed?
A
- Surgical excision: 4-6mm margin
- 4mm if lesion <20mm
- 6mm if lesion > 20mm
- Mohs micrographic surgery (high risk, ill-defined, large recurrent tumours)
- Radiotherapy for large, non-resectable tumours and metastases.
27
Q
What is a basal cell carcinoma?
A
- Aka rodent ulcer
- Slow-growing, locally invasive malignant tumour of epidermal keratinocytes. Rarely metastasizes. Typically affects older people.
- Most common skin cancer
- Presentation:
- Most common over head and neck.
- Nodular (most common)= pearly rolled edge, small, skin coloured papule or nodule, surface telangiectasia (widened venules, thread-like lines on skin), may have necrotic/ulcerated centre. on sun exposed sites.
- Also – superficial (most common type in younger adults), cystic, sclerosing, keratotic, pigmented.
28
Q
How is BCC managed?
A
- Surgical excision: excision (histological examination – excisional, incisional, punch and shave biopsy) - 4-6mm margin
- Mohs micrographic surgery (removal of cancer thin layer at a time),
- Other: Cryotherapy, curettage, radiotherapy, phototherapy
- TopicalL: For superficial/ low risk BCC: 5FU + imiquimod
29
Q
What is actinic keratosis?
A
- Overview: most common precursor lesion for SCC. Pre-malignant change of the skin caused by chronic sun exposure.
- Risk factors: increasing age, immunosuppression, photosensitivity, XS UV exposure.
- Pathophysiology: XS UV exposure resulting
- Presentation: Flat, crusty, thickened papules or plaques. Can be red, pink, brown, or same colour as skin, typically seen on sun exposed areas. Crumbly yellow white scaly crusts on sun exposed skin
30
Q
How is actinic keratosis mxd?
A
- Conservative: Prevention of further risk – sun avoidance, sun cream
- Medical
- 5-FU cream – 2-3w course, skin may become red and inflamed initially so topical hydrocortisone might be used to settle the inflammation
- Topical diclofenac for mild cases
- Removal by cryotherapy (liquid nitrogen spray)
31
Q
What is Bowens disease?
A
- Overview: intraepidermal squamous cell carcinoma, also known as an SCC in situ. Atypical keratinocytes found throughout the epidermis without invasion through the basement membrane.
- Risk factors: More common in elderly females, often found on sun-exposed skin.
- Presentation: red, scaly patches/ plaques, often on sun exposed areas
32
Q
How is Bowens disease mxd?
A
- Medical: Topical 5-FU (OR imiquimod), cryotherapy, photodynamic therapy
- Surgical: excision, curettage + cautery
