Miscellaneous Flashcards
What is acanthosis nigricans?
Symmetrical, brown, velvety plaques, often found on the neck, axilla and groin.
What conditions is acanthosis nigricans associated with?
T2DM GI cancer Obesity PCOS Acromegaly Cushing's disease Hypothyroidism Familial Prader-Willi syndrome COCP and nicotinic acid
What is the pathophysiology of acanthosis nigricans?
Increased insulin resistance –>
Hyperinsulinemia –> Stimulation of keratinocytes and dermal fibroblasts –> Proliferation via interation with insulin-like growth factor-1.
What is acne rosacea?
Chronic skin disease of unknown aetilogy.
What is the appearance of acne rosacea?
Typically affects the nose, cheeks and forehead
Flushing - first symtpom
Telangiectasia
Develops into persistent erythema with papules and pustules
Rhinophyma
Ocular involvement - blepharitis
What may exacerbate the symptoms of ace rosacea?
Sunlight
What is the treatment of acne rosacea?
Topical metronidazole Topical brimonidine Systemic abx: Oxytetracycline Daily suncream Comflage cream Laser therapy
What is actinic (solar) keratoses?
A common pre-malignant skin lesion that develops as a consequence of chronic sun exposure.
How does actinic keratoses appear?
Small, crusty or scaly lesions
Pink, red, brown or skin colour
Typically on sun-exposed areas
Multiple lesions may be present
What is the management of actinic keratoses?
Sun avoidance, sun cream Fluorouracil cream Topical diclofenac Topical imiquimod Cryotherapy Curettage and cautery
What is Bowen’s disease?
A type of intraepidermal squamous cell carcinoma.
More common in elderly females - 3% development into invasive cancer.
How does Bowen’s disease present?
Red, scaly patches
Often occur on sun-exposed areas
What are the management options of Bowen’s disease?
Topical 5-fluorouracil or imiquimod
Cryotherapy
Excision
What is a cherry haemangioma?
(Campbell de Moran spots)
Benign skin lesions which contain an abnormal proliferation of capillaries.
What are the features of a cherry haemangioma?
Erythmatous, papular lesion
Typically 1-3 mm in size
Non-blanching
Not found on the mucous membranes
Benign - no treatment required
What is chondrodermatitis nodularis helicis (CNH)?
Common and benign - development of a painful nodule on the ear.
What are the causes of chondrodermatitis nodularis helicis (CNH)?
Persistent pressure on ear
Trauma
Cold
What is the management of chondrodermatitis nodularis helicis (CNH)?
Reducing pressure on the ear: foam 'ear protectors' may be used during sleep Cryotherapy Steroid injections Collage injections Surgery
What is dermatitis herpetiformis?
An autoimmune blistering skin disorder associated with coeliac disease. Caused by IgA deposition in the dermis.
What is the presentation of dermatitis herpetiformis?
Itchy, vesicular skin lesions on the extensor surfaces (e.g. elbows, knees, buttocks)
How is dermatitis herpetiformis diagnosed?
Skin biopsy: direct immunofluorescence shows deposition of IgA in a granular pattern in the upper dermis
How is dermatitis herpetiformis managed?
Gluten-free diet
Dapsone
What is eczema herpeticum?
A severe primary infection of the skin by HSV 1 or 2.
Who does eczema herpeticum usually present in?
More commonly seen in children with atopic eczeema and often presents as a rapidly progressing painful rash.
How does eczema herpeticum usually present?
Monomorphic punched-out erosions (circular, depressed, ulcerated lesions), usually 1-3mm in diameter.
What is the treatment f eczema herpeticum?
Potentially life-threatening, children should be admitted for IV aciclovir.
What is erythema ad igne?
Caused by over exposure to infrared radiation.
Reticulated, erythmatous patches with hyperpigmentation and telangiectasia.
(Typical history elderly woman who always sits next to an open fire)
(Looks like mottled skin)
What is erythema ad igne a risk factor of?
Squamous cell skin cancer
What is erythema nodosum?
Inflammation of subcutaneous fat
Typically causes tender, erythmatous, nodular lesions
Typically occurs over the shins, may occur elsewhere
Usually resolves within 6 weeks
Lesions heal without scarring
What are the causes of erythema nodosum?
Infection - streptococci, TB, brucellosis
Systemic disease - sarcoidosis, IBD, Behcet’s
Malignancy/lymphoma
Drugs - penicillins, sulphonamides, COCP
Pregnancy
What is erythrasma?
Generally asymptomatic, flat, slightly scaly, pink or brown rash usually found in the groin or axillae.
What causes erythrasma?
Overgrowth of the diphtheroid Coryneacterium minutissimum
How is erythrasma diagnosed?
Wood’s light reveals a coral-red fluorescence
What is the treatment of erythrasma?
Topical miconazole or antibacterial are usually effective.
Oral erythromycin.
What is erythroderma?
A term used when more than 95% of the skin is involved in a rash of any kind.
Extensive exfoliation may also occur.
What are the causes of erythroderma?
Eczema Psoriasis Drugs e.g. gold Lymphomas, leukaemias Idiopathic
What is erythrodermic psoriasis?
May result from progression of chronic disease to an exfoliative phase with plaques covering most of the body. Associated with mild systemic upset.
May be triggered by withdrawal of systemic steroids.
What is granuloma annulare?
Quite large papular lesions that are often slightly hyperpigmented and depressed centrally
Typically occur on the dorsal surfaces of the hands and feel and extensor aspects of arms and legs.
What are some associations of granuloma annulare?
Diabetes mellitus
What is hereditary haemorrhagic telangiectasia (HHT)?
(Osler-Weber-Rendu syndrome)
What is the inheritance pattern of HHT?
Autosomal dominant condition
50% occur without fHx
What is the presentation of HHT?
Multiple telangiectasia over the skin and mucous membranes.
What are the diagnostic criteria for HHT?
Epistaxis
Telangiectases
Visceral lesions e.g. GI telangiectasia, pulmonary AVM, hepatic AVM, cerebral AVM, spinal AVM.
Family history: 1st degree relative
2/4 - possible
3/4 - definitive diagnosis
What is hirsuitism?
Describes androgen-dependent hair growth in women
What is hypertrichosis?
Describes androgen-independent hair growth in women.
What are the causes of hirsuitism?
PCOS (most common) Cushing's syndrome CAH Androgen therapy Obesity: due to insulin resistance Adrenal tumour Androgen secreting ovarian tumour Drugs: phenytoin, corticosteroids.
What scoring system is used to assess hirsutism?
Ferriman-Gallwey score:
>15 moderate - severe
What is the management of hirsuitism?
Weight loss
Cosmetic techniques
COCP (Dianette)
Topical eflornithine
What are causes of hypertrichosis?
Drugs: minoxidil, ciclosporin, diazoxide
Congenital
Porphyria cutanea tarda
Anorexia nervosa
What is hyperhidrosis?
Excessive production of sweat
What are the management options of hyperhidrosis?
Topical aluminium chloride
Iontophoresis
Botulinum toxin
Surgery
What are keloid scars?
Tumour-like lesions that arise from the connective tissue of a scan and extend beyond the dimensions of the original wound.
What are predisposing factors to developing a keloid scar?
Ethnicity: darker skin
Younger adults
Common sites: sternum, shoulder, neck, face, extensor surface of limbs, trunk.
What is the treatment of keloid scars?
Intra-lesional steroids e.g. triamcinolone
Excision
What formulation of ketoconazole be used?
Only topical due to risk of heptic toxicity systemically
What is koebner phenomenon?
Typically in psoriasis, describes the formation of psoriatic skin lesions on parts of the body that aren’t typically where a person with psoriasis experiences lesions, following an injury.
What conditions is Koebner phenomenon associated with?
Psoriasis Vitiligo Warts Lichen planus Lichen sclerosus Molluscum contagiosum
What is Lentigo maligna?
A type of melanoma in-situ. Typically progresses slowly but may at some stage become invasive causing lentigo meligna melanoma.
What is Leukoplakia?
Premalignant condition which presents as white, hard spots on the mucous membranes of the mouth, More common in smokers.
What are the differentials for Leukoplakia?
Candidiasis
Lichen planus