Speciality: Dermatology Flashcards
Patient - Itchy, red, scaly patches on the flexural surfaces. ACF, popliteal fossae.
Eczema
Eczema Aetiology
- Genetic FHx
- Atopy
- Hygiene hypothesis
- Climate - heat and cold causes flares.
- Food antigens.
Eczema Pathology
- Primary immune dysfunction - IgE sensitisation and allergic inflammation.
- Primary defect of the epithelial layer.
Eczema Presentation
- Itchy, red, scaly patches on the flexural surfaces.
- In infants, can start on the face.
- Acute lesion can weep.
- Can become super infected w/ staph aureus.
- Excoriations.
- Eczema herpeticum - super infection with HSV.
Eczema Ix
1) Clinical
2) Bloods; eosinophilia and high IgE
3) Skin swabs if super-infection (Black for bacteria and Green for virus)
Eczema Rx
1) Education of trigger avoidance
2) Emollients
3) Steroids - topical hydrocortisone.
4) Topical immunomodulators - tacrolimus
5) ABx for superinfection - often flucloxacillin
6) Sedating antihistamines for itch
7) Bandaging
8) Systemic immunosuppression - Ciclosporin
Patient - Red, scaly patches w/ silver scales. Extensor surfaces, lower back, scalp, ears.
Psoriasis
Psoriasis Aetiology
- Polygenic
- Environmental triggers - cold, stress, alcohol, drugs, infection
- TNF
Psoriasis Pathology
- Skin biopsy shows; epidermal acanthosis and parakeratosis.
- Increased skin turnover
- Polymorphonuclear cells present in upper epidermis.
Psoriasis Presentation
- Chronic plaque psoriasis
- Flexural psoriasis
- Guttate psoriasis - rain drop like pattern, explosive eruption of small circular/oval plaques on the trunk.
- Nail changes - pitting, separation from the nail bed, yellowing
- Arthropathy
Psoriasis Ix
1) Clinical
2) Bloods; CRP & RF (PSa is seronegative)
Psoriasis Rx
1) Education around triggers
2) Emollients + skin cleaning and bandaging
3) UV exposure
4) Topical steroids
5) Vitamin D analogues (calcipotriol)
6) Severe = immunomodulators such as MTX ow + folic acid. AZA.
7) Biologics - Etanercept, adalimumab, infliximab.
Patient - Teenager w/ blackheads and lots of spots
Acne
Acne Aetiology
- Multifactorial
- Follicular epidermal hyper-proliferation.
- Blockage of pilosebaceous units
- Increased sebum production
- Infections w/ Propionibacterium acnes.
Acne Presentation
- Infantile acne
- Steroid induced acne
- Oil acne (work)
- acne fulminans - young males, severe necrotic and crusted lesions w/ malaise, pyrexia and arthralgia –> Rx urgently w/ oral pred followed by isotretinoin.
- Presents on the face, back, sternum.
- Open comedones (black) or closed comedones (whiteheads)
- Papules/pustules
- Greasy skin
Acne Ix
1) Clinical Dx
2) Skin swab for super-infection.
Acne Rx
1) Regular face washing to reduce oils
2) topical agents (kerolytics - benzoyl peroxide) or topical retinoids (tretinoin or isotretinoin) + topical erythromycin or clindamycin.
3) Low dose oral oxytetracycline 500mg Bd
4) Oral isotretinoin (in those w/ scarrin)
Patient - facial malar type flushing w/ papules and pustules around the nose, forehead and cheeks. Telangiectasia
- Rosacea
Rosacea Aetiology
- UK
- Potential underlying vasomotor instability
- Skin mite demodex
- Associated w/ blepharitis, conjunctivitis and keratitis.
Rosacea Presentation
- Often middle aged females
- Facial flushing w/ inflammatory pustules and papules.
- Telangiectasia
- Enlarging of the nose
- Flushing exacerbated by alcohol, sun and heat
Rosacea Ix
1) Clinical
Rosacea Rx
1) Long term use of topical 0.075% metronidazole or topical azelaic acid
2) 3 month course of oral tetracycline 500mg BD
3) Laser for telangiectasia.
SCC Aetiology
- Pre-malignant form = Solar keratoses. Silver-scalp papules or patches w/ conical surface and red base.
- Bowen’s disease = Intraepidermal Carcinoma in situ. Looks like psoriasis.
SCC Presentation
- Asymptomatic
- Lesions are keratotic, ill-defined nodules which can ulcerate.
- Can grow fast and metastasize.
SCC Ix
1) Clinical
2) Confirmed w/ biopsy and pathology
SCC Rx
1) Solar keratoses = Cryo or topical 5-FU cream
2) SCC = WLE, radio.
BCC Aetiology
- Sun exposure
- Genetics - Gorlin’s syndrome
- Immunosuppression.
BCC Presentation
- Common on sun exposed sites (not ear)
- Slow growing papule or nodule
- Roled pearly edge
- Telangiectasia.
BCC Ix
- Clinical
BCC Rx
1) Surgical excision w/ controlled borders. Mohs procedure for sensitive areas.
2) Cryotherapy
3) Radio
MM Aetiology
- Excessive sunlight
- RF’s = pale skin, lots of moles, immunosuppression, Lentigo maligna.
- Oncogenes; CDK4, PTEN.
MM Presentation
1) Lentigo maligna melanoma - patch of lentigo maligna develops a papule or nodule.
2) Superficial spreading MM - Large flat irregularly pigmented lesion growing laterally.
3) Nodular MM - Most aggressive, rapidly growing pigmented nodule which bleed and ulcerates.
MM Ix
1) Clinical A- asymmetry B- Border irregularity C - Colour variation D - Diameter >6mm E - Elevated 2) Dermatoscope 3) Excise then histology
MM Rx
1) Surgery - WLE
2) Sentinel node biopsy
3) Mets = chemo/radio
Impetigo Aetiology
- Staphylococcus or GAS
- Abnormal skin flora imbalance
Impetigo Presentation
- Weeping exudative areas w/ a honey crusted surface.
- Often around the face/mouth.
Impetigo Ix
1) Clinical
2) Skin swab + MC&S
Impetigo Rx
1) Prevention w. good hygiene
2) Topical fusidic acid.
3) Oral Fluclox for Saureus 500mg 4xdaily or phenoxymethylpenicillin 500mg 4xdaily for GAS.
HSV Aetiology
- Most facial cold sores = HSV 1
- Immunosuppression.
- Colds and illness.
- Can superinfect eczema.
HSV Presentation
- Clusters of painful blisters on the face.
- Painful gingivalstomatitis
- Cold sore
HSV Ix
1) Clinical
2) Skin swab + PCR
HSV Rx
1) Oral valaciclovir (500mg BD 5 days) for primary and painful HSV
2) Topical acyclovir for cold sores.
Athletes foots.
- Causes
- Presentation
- Ix
- Rx
- Fungal
- Trichophyton - Scaling, flaking, itching between toes.
- Clinical
- Swab
- Toenail clippings - Topical miconazole.
Dermatitis herpetiformis
- Causes
- Presentation
- Ix
- Rx
- Autoimmune associated with Coeliac disease.
- Deposition of IgA in the dermis. - Itchy, vesicular rash on the extensor surfaces; elbows, knees, arse
- Skin biopsy + direct immunofluorescence shows IgA in the dermis.
- Gluten free diet.
- Dapsone
Pyoderma gangrenosum
- Causes
- Presentation
- Ix
- Rx
- Idiopathic
- IBD
- RA/SLE
- Lymphoma
- PBC - Lower limbs
- Initially a small red papule which develops into a red, necrotic ulcer with a violaceous border.
- Systemic Sx. - Bloods - infection and inflammation
- Autoantibodies (p-ANCA)
- Swabs and MC&S
- Biopsy. - Oral steroids as first line.
- Difficult cases = cyclosporin or infliximab
Lichen Sclerosus
- Causes
- Presentation
- Ix
- Rx
- Inflammatory condition which effects the pussy or the penis.
- More common in women.
- Atrophy of the epidermis. - Itch
- White plaques - Clinical
- Biopsy if atypical or suspicious of VIN. - Increased risk of Ca
- Vulval Ca in women
- Rx with topical steroids and emollients.
Acanthosis nigerians associated conditions
- GI cancer
- DM
- Fatness
- PCOS
- Acromegaly
- Cushing’s
- Hypothyroidism
Venous ulcers
- Causes
- Presentation
- Ix
- Rx
- Venous blood flow return insufficiency
- Ulcer above the medial malleolus.
- ABPI - normal = 0.9-1.2 and indicate lack of arterial disease.
- Values below 0.9 or above 1.3 indicate arterial disease. - Compression bandaging, 4 layers.
- Little evidence for much else.
- Keep clean and prevent infection.
Scabies
- Causes
- Presentation
- Ix
- Rx
- Mite = Sarcoptes scabiei
- Spread via skin contact.
- Mite burrows into the skin and lays eggs in the stratum corneum. - Itching
- Linear burrows on the side of the fingers.
- Worse at night
- Secondary features of scratching and infection. - Clinical
- Permethrin 5% first line
- Malathion 05% is second line.
Hereditary haemorrhagic telangiectasia
- Causes
- Presentation
- Ix
- Rx
- AD inherited.
- Multiple telangiectasia over the skin and mucous membranes.
- diagnostic criteria =
a) Epistaxis - spontaneous and recurrent
b) Telangiectasia - lips, fingers, nose and oral cavity
c) FHx - Capillary microscopy.
- CT/MRI for lesion identification
- Often clinical - Acute haemorrhage w/ empirical Rx such as blood Tx etc.
- Surgical or laser ablation of telangiectasia.
- Septoplasty of the nose
Lichen Planus
Purple, pruritic, papular, polygonal rash on the flexor surfaces.
Granuloma annulare
- Papular lesion
- Hyperpigmented
- Central depression
- occur on the arm and legs.
- Associated w/ DM
Side effects of Isotretinoin
- Teratogenicity
- Dry skin, lips and eyes
- Low mood
- Raised triglycerides
- Nose bleeds
Hirsutism
- Causes
- Presentation
- Ix
- Rx
- PCOS
- Cushing’s
- CAH
- Androgen therapy
- Obesity
- Adrenal tumour
- Drugs - Increased hair growth
- Male pattern hair growth
- Ferrimen-gallwey scoring system; 9 areas. - Clinical
- Testing for causes listed above. - Cosmetic techniques; waxing etc.
- Use of COCP
Pityriasis Versicolour
- Causes
- Presentation
- Ix
- Rx
- Fungal skin infection
- Malassezia furfur
- RF’s = immunosuppression, malnutrition and cushing’s - Commonly affects the trunk
- Hypopigmented patches; pink or lighter brown.
- Scale
- Itch - Clinical
- Skin scraping for MC&S - Topical antifungal - ketoconazole shampoo
Erythema Nodosum
- Causes
- Presentation
- Ix
- Rx
- Inflammation of Subcut fat
- Sarcoidosis
- IBD
- Infection (TB)
- Drugs; penicillin’s, COCP. - Tender, red, nodular lesion
- Often on the shin
- Heals w/o scarring. - Throat swab for strep.
- CSR for sarcoidosis
- Serum ACE
- Look for cause. - Self-limiting
- Symptom relief only
- NSAID’s can help.
- Bed rest w/ foot elevation.
Tinea (ring worm)
- Causes
- Presentation
- Ix
- Rx
- Fungal - dermatophytes
- Well defined, annular with central clearing.
- Red lesions w/ pustules and papules - clinical
- Oral fluconazole
Erythroderma
- Causes
- Presentation
- Ix
- Rx
- When 95% of the body is covered in a rash
- Eczema
- Psoriasis
- Lymphoma
- idiopathic
- Drug reaction. - Widespread erythema of the skin.
- Scaling
- excoriation
- itching. - Clinical
- Monitor as inpatient
- Complications include; dehydration, infection and HF
- bed rest
- Emollients and wet dressings.
- Nutritional support.
- Steroids or ciclosporin and infliximab