Rash clinical cases Flashcards
How should any rash be assessed?
Detailed history, examination (distribution/site affected, morphology, secondary features)
How common is psoriasis?
Occurs in 2% of adults
Is psoriasis curable?
No-has chronic course
What is the most common form of psoriasis?
Chronic plaque psoriasis (psoriasis vulgaris)
What are some features of chronic plaque psoriasis?
Symmetrical, commonly extensors (elbow/knee), scalp, sacrum, hands, feet, trunk and nails, sharply demarcated, scaly, erythematous plaques
What is the Koebner phenomenon?
Psoriasis develops in areas of skin trauma
What is the Auspitz sign?
Removal of psoriasis surface scale reveals tiny bleeding points (dilated capillaries in elongated dermal papillae)
What are some forms of psoriasis?
Guttate, palmoplantar pustular, erythrodermic or widespread pustular (rare)
What are some sign of psoriatic nail disease?
Nail pitting, subungal hyperkeratosis, dystrophy, onycholysis
What are some systemic effects of psoriasis, and what are some of the co-morbidities?
Biomarkers of systemic inflammation are raised; psoriatic arthritis, obesity, hypertension, diabetes, lipid abnormalities, Crohn’s, depression, cancer, uveitis
What is the life expectancy for patients with severe psoriasis?
About 4 years due to increased CV risk (3 x more at risk of MI)
Who controls the topical therapies for psoriasis?
GPs
What are some topical therapies for psoriasis?
Vitamin D analogues, Calcipotriol (Dovonex-for localised plaques), Calcitriol (Silkis-for flexures, less irritating), coal tar, dithranol, steroid ointments, emollients
When is dithranol used to treat psoriasis?
If few localised plaques and short contact
What is the risk of using steroid ointments to treat psoriasis?
Can cause rebound if potent
What are some specialised treatments for psoriasis?
Phototherapy (narrowband UVB and PUVA), immunosuppression (methotrexate), immune modulation
What is acne vulgaris?
Chronic inflammation of the pilosebaceous unit
What is the typical age range of acne sufferers?
14-17 years old in females, 16-19 old years in males
What is the pathogenesis of acne?
Portal occlusion, bacterial colonisation of duct, dermal inflammation, increased sebum production
What does the distribution of acne reflect?
Sebaceous gland distribution (face, upper back, anterior chest)
What is the primary lesion in acne?
Comedones = open (blackheads), closed (whiteheads)
What are some of the skin changes that can form in acne?
Pustules and papules, cysts, erythema
What kinds of scarring can occur in acne?
Atrophic, ice-pick, texture changes, hypertrophic
How is acne graded?
Mild = scattered papules and pustules, comedones Moderate = numerous papules, pustules and mild atrophic scarring Severe = cysts, nodules and significant scarring
What are some topical acne treatments?
Benzoyl peroxide (keratolytic, antibacterial), vitamin A derivatives (retinoids = drying effect), antibiotics (antibacterial and anti-inflammatory)
How long should antibiotic treatment of acne last for?
At least six months
What does Isotretinon do?
Oral systemic retinoid = effect on sebaceous gland activity
What is an issue with systemic treatment of acne?
Lots of side effects including initial aggravation of acne
Where does rosacea tend to affect?
Nose, chin and forehead
What age group does rosacea tend to occur in?
Age 30-60
What are some features of rosacea?
Papules, pustules, erythema, prominent facial flushing, enlarged/unshapely nose (rhinophyma), conjunctival/gritty eyes
Why does rosacea not cause comedones?
It isn’t a disease of the pilosebaceous units
What are some triggers of rosacea?
Sudden temperature change, alcohol, spicy food
What are some ways to avoid the aggravating factors of rosacea?
Wear high factor sunscreens, avoid spicy foods and topical steroids
What are some topical therapies for rosacea?
Metronidazole, ivermectin (for demodex mite)
What are some oral therapies for rosacea?
tetracycline (long term), isotretinoin (low dose if severe)
What are some additional treatments for rosacea?
Vascular laser for telangiectasia, surgery/ laser shaving for rhinophyma
What characterises lichenoid eruptions?
Damage and infiltration between the epidermis and dermis
What are two examples of lichenoid eruptions?
Lichen planus, lichenoid drug eruptions
What age group commonly gets lichen planus?
Middle aged patients
What occurs in lichen planus?
T cell mediated inflammation targeting an unknown protein within the skin and mucosal keratinocytes
What is the skin manifestation of lichen planus?
Viloaceous (purple/pink) flat-topped shiny papules, intensely itchy
Where does lichen planus typically affect?
The volar wrists/forearms, shins and ankles
What is Wickhams striae as a sign of lichen planus?
Fine lace like pattern on surface of papules and buccal mucosa (often asymptomatic)
How long does lichen planus typically last before burning out?
12-18months
What is the management of lichen planus?
Check if possible drug precipitant, emollients, treat symptomatically (potent/very potent topical steroids, oral steroids if extensive), UVB phototherapy or PUVA
What are bullous disorders?
Autoimmune diseases where damage to adhesion mechanisms in the skin results in blistering at various levels
What are the main bullous disorders?
Bullous pemphigoid (split is deeper, through DEJ), pemphigus (split more superficial, intra-epidermal), dermatitis herpetiformis
What are the features of dermatitis herpetiformis?
Associated with Coeliac, intensely itchy, vesicles removed by scratching leaving erosions, symmetrical on scalp, shoulders, elbows, knees and buttocks
What is Nikolsky’s sign?
Top layers of skin slip away from the lower layers when slightly rubbed, indicates plane of cleavage within the epidermis
What are the features of bullous pemphigoid?
Elderly patients, localised to one area/widespread on the trunk and proximal limbs, non-scarring, mucosal lesions unlikely, Nikolsky’s sign negative, itchy erythematous plaques and papules may be the presenting feature
What are the features of Pemphigus vulgaris?
Typically affects scalp, face, axilla and groin, flaccid vesicles/bullae (thin roofed), lesions rupture and leave raw areas (increased infection risk), Nikolsky’s sign positive, mucosal involvement very common (eyes, genitals
What is the prognosis of bullous disorders?
Chronic self-limiting course, duration varies from months to years, most patients achieve remission within 3-6 months, pemphigus has high mortality if left untreated, bullous pemphigoid has much lower risk
What are the investigations for bullous disorders?
Skin biopsy with direct immunofluorescence, indirect immunofluorescence
What is the general treatment for bullous disorders?
Systemic steroids and other immunosuppressive agents
What is the treatment for pemphigus?
Tetracycline
What topical treatments are used for bullous disorders?
Emollients, topical steroids, topical antiseptics/hygiene measures
