Miscellaneous Flashcards
Erythema Multiforme
Hypersensitivity Reaction affecting skin and mucosal surfaces
Clinical features
- Erythematous macules and papules with concentric rings.
- Found on back of hands, palms, forearms, face but can be anywhere else.
- triggers - Idiopathic, HSV, Mycoplasma pneumonia, TB, Streptococcus, adenovirus, HIV, Drugs (Barbituates, penicillin, sulfonamides, phenothiazines, phenytoin.), Hodgkins Lymphoma, Systemic Lupus erythematosus
- Appearance - Raised macules with concentric rings usually at mouth and extremities.
Management
- Remove triggers
- Apply emolient
- Diprosone 0.05% ointment OD x 2 weeks
Melasma
- Bilateral blotchy brownish facial pigmentation
- Photoaging disorder in genetically predisposed individuals.
- Overproduction of melanin by melanocytes taken up by keratinocytes (epidermal melanosis) or deposited in the dermis (dermal melanosis)
- Risk:
- F
- 20-40yo
- Fitz III-V,
- Fam Hx (60% of cases)
- ^ Sun exposure
- Oestrogen Hormone exposure (pregnancy, COCP, Implanon, HRT 25% of cases)
- Thyroid disorder (Hypothyroidism)
- Medications and scented products (new cancer treatments and perfumed soaps/toiletries/cosmetic cause phototoxic reaction to trigger melasma.
Rx
- Change to non-oestrogen contraceptive method.
- Sun protection to affected areas
- Topical retinoids (Tretinoin 0.025% Applied to affected area once daily)
- Cosmetic camouflage
- Depigmenting agent - Hydroquinone 2% cream TOP BD x 2-4months
Tinea Cruris
Dermatophyte infection involving crural fold
- Predisposing factors - Hyperhydrosis, Immunodeficiency, Obesity, Diabetes
Diagnosis
- Skin scrapings from active border for potassium hydroxide examination.
Differential
- Flexural psoriasis, Candidal intertrigo, seborrhoeic dermatitis, erythrasma
Management
- Topical terbinafine TOP OD x 7-14 days / Clotrimazole once daily
- PO Terbinafine 250mg PO OD x 2 weeks / Fluconazole 150mg PO once weekly for 6 weeks.
- Avoid sharing towels
- Avoid wearing tight-fitting clothing / Keep the area dry.
- BMI 18-25.
Shingles
Reactivation of VZV ina dermatomal distribution.
- Vesicular rash on an erythematous base.
Non-pharmacological management
- Keep rash fully covered at all times
- Avoid touching the rash
- Wash hands regularly
- Avoid contact with children < 18/12, pregnant, elderly
Antiviral therapy if present < 72 hours.
- Valaciclovir 1g PO TDS x 7 days
- Famciclovir 500mg PO TDS x 7 days
- 2nd line - Aciclovir 800mg PO 5 times daily x 7 days.
Neuropathic Analgesia
- 1st - Pregabalin / Gabapentin
- 2nd - Nortriptyline, Amitriptyline, Duloxetine, venlafaxine
Herpes Zoster Opthalmicus? Refer to opthal for adjunctive topical steroid drops and to review for keratitis/iritis.
Zostavax if > 70 yo and 12 months after previous shingles infection.
Shingrix now becoming available as 2 dose (2 months apart) regimen and has higher efficacy than zostavax. Can be used in immunocompromised adults > 18yo
Genital Warts
Alternative diagnoses
- Pearly penile papules, fodyce spots, tyson glands, vestibular papillae
Note - HPV types related Genital warts have not been directly associated with causing cancer.
Rx
- Cryotherapy with repeat intervals of 1-2 weeks.
Topical preparations
- Podophyllotoxin 0.5% pain BD for 3 days followed by 4 day break. Repeat weekly for 4-6 cycles until warts resolve
- Imiquimod 5% cream 3 times weekly on alternate days until warts resolve (usually 8 to 16 weeks)
Generalised pruritus without primary skin lesions
Very broad differential
- Renal failure / Uraemia
- Liver disease
- Diabetes
- Thyroid disease (Hyper and Hypo)
- Hyperparathyroidism
- Iron Deficiency Anaemia
- Psychogenic
- Solid Malignancy (Lung, colon, brain)
- Haematological malignancy (Lymphoma, multiple myeloma, leukaemia)
- Paraneoplastic syndrome from malignancy
- Polycythaemia
- Macroglobulinaemia
- Neurological (Cerebral infarct, brain abscess, MS, PD)
- Infectious (HIV, HCV)
Rx
- Find and treat underlying cause
- Emolient for skin dryness.
Patient Education points prior to commencing Isotretinoin
- Typical course is 6-9/12
- Potent teratogen requiring two methods of contraception while being taken and for one menstrual cycle after medication is completed.
- Oral POP is unsuitable during isotretinoin use due to increased risk of poor compliance.
- Skin and mucosal irritation (Dry skin, eyes, mucosa, lips, nose-bleeds)
- Increased UV senstivity. Ensure adequate sun protectoin
- Can cause myalgia and joint stiffness.
- Regular follow up required to monitor liver function.
Psoriasis Management
- Topical corticosteroid. Use initially to control flare
- Tars and Keratolytics - LPC + Salicylic Acid. Add to therapy when inflammation is controleld as can be quite irritating otherwise. % of acid is 3 - 8%
- Calcipotriol - 1,25-dihydroxivitamin D analogue that regulates proliferation and differentiation of keratinocytes. Can take up to 6 weeks to see adequate clearance. Use as adjunct to above treatment.
- Note: Daivobet (Calcipotriol 50 + Betamethasone Diprionate 500) ointment or foam. Good to use in patients who need longer term use of potent corticosteroid with combination of Calcipotriol. Use for around 6 weeks.
- Remove potential triggers - ACEi, NSAIDS, lithium, hydroxychloroquine, IFN-a, GM-CSF, withdrawal of corticosteroids, Infections (streptococcal, viral including HIV), Skin trauma (Koebner phenomenon), stress, Alcohol, Sunburn, calcium deficiency, pregnancy, post-partum
- Review psychological impact on patient
- Review for co-morbidities (CVDRisk, psoriatic arthritis, IBD, ocular disease)
- Lifestyle management - Stress management, exercise, weight loss, smoking cessation, reduced alcohol intake, diabetes screening.
Grover Disease
Transient Acantholytic Dermatosis
- Unknown cause. Potential association with sweat duct damage and occlusion
- Frequent associated with skin occlusion, heat and sweating.
- Possible associated with drugs. Metabolites excreted in sweat causing toxic effects to adjacent skin.
- Affects middle-aged individuals
- M > F
- Can be mistaken often as a heat rash.
- Histology shows acantholysis (splitting of the epidermis)
- Can resolve over a few months or persist for years
Clinical Features
- Sudden onset.
- Location - Central back, mid chest, upper arms.
- Small, red, crusted or eroded papules or vesicles.
- Typically intensely itchy
Management
- Remain cool, as sweating may induce more itchy spots
- Topical Emolient when skin is dry (QV)
- Moderate-potency CS for itch / rash
- Betamethasone Valearate 0.02% cream TOP BD x 2-6weeks
- Triamcinolone acetonide 0.02% cream TOP BD x 2-6weeks
- Refractive to above? Refer to Derm (Can consider UV phototherapy and retinoids such as acitretin)
Chilblains
Perniosis
Localised inflammatory lesions caused by prolonged vasoconstriction and ischaemia from exposure to cold.
Acutely burning red or purple swellings to toes or foot but can also affect nose, ears and thighs.
Risk Factors
- Female, Low body weight. Impaired peripheral circulation
Management
- Avoid cold environments
- Wear clothing to keep extremities warm (thick socks, glioves,)
- Cessation of smoking.
- Soak extremities in warm water before exposure.
- Pain? Use a potent topical corticosteroid
- Betamethasone diprionate 0.05% ointment TO BD
- Severe and recurrent? Consider preventive therapy in colder months
- Vasodilators
- Nifedipine 30mg PO BD
- Topical GTN 0.2% Daily
Vitiligo
Pigment loss of skin
- Unknosn cause. Can be associated with autoimmune diseases
Rx
- Avoid sunburn to affected areas
- Cosmetic camouflage
- Topical therapy
- Betamethasone Diprionate 0.05% cream OD x 3 months
- Face? Pimecrolimus 1% cream TOP BD x 3 months
- 2nd line can use topical calcipotriol.
- UV Phototherpay with Specialist
Keratosis Pilaris
Common dry skin condition caused by keratin accumulation in hair follicles predominantly on upper arms and thighs.
Management
- Urea 10% cream daily after bathing.
- 2nd - Tretinoin 0.025% cream TOP Nocte
- Salicylic acid 3% in sorbolene cream OTP OD
Eczema Herpeticum
- Disseminated viral infection to skin characterised by fever and clusters of itchy vesicles.
- Can be complication of area affected by atopic dermatitis exposed to HSV type 1 or 2
- Signs appear 5-12 days after contact
- New patches can form over 7-10 after initial symptoms.
- Can be complicated by impetigo or cellulitis
Milker’s Nodule
Caused by parapoxvirus.
- Mild infectiosn on the teats of cows and ulcers in the mouth of calves.
INcubation 5-14 days -> Small, red, raised flat-topped spots -> Firm, tender blisters or nodules.
Usually on the hands but occasionally on the face of the milker.
Can lead to erythema multiforme.
Orf is the Sheep version of milker’s nodule.
Treatment
- Reassurance.
- Self-limiting with spontaneous resolution with 4-6 weeks.
Erythema Nodosum
- Panniculitis (inflammation of the subcutaneous fat_
- Painful erythematous indurated placques and nodules usually on lower legs.
- Associated with fever, malaise, arthralgia
- Typically resolve over 2-3 weeks. Leaves discoloration but no scarring.
Causes
- Sarcoidosis (Commonest)
- Infections - GBS pharyngitis, HBV, TB, Leprosy, Chlamydia, HSV, HIV, EBV, Fungal, Bacterial gastroenteritis
- IBD
- Drugs - Sulphonamides, Tetracyclines, COCP, Bromides, Iodides
- Malignancy - Lymphoma, Leukaemia
- Pregnancy
- Idiopathic (40% of all cases)
Investigations
Baseline
- FBC, ESR, EUC
(finding underlying cause)
- CXR (Sarcoidosis / TB)
- Mantoux test (TB)
- ASO titre (GBS pharyngitis)
- Bacterial throat swab (GBS pharyngitis)
Management
- Bed rest + NSAIDS 1st line
- Consider Prednisolone 25mg PO OD x 14 days then taper if symptoms severe
- Leg elevation
- Compression bandages / stockings
- Cease possible precipitants (Meds)
