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
How is the diagnosis for Leukoplakia made?
Biopsies
What is lichen planus?
A skin disorder of unknown aetiology, most probably immune-mediated
What are the features of lichen planus?
Itchy, papular rash most common on the palms, soles, genitalia and flexor surfaces of the arms.
Often polygonal in shape, with ‘white-lines’ pattern on the surface (Wickham’s striae)
Koebner pnenomenon may be seen
Oral involvement (50%)
Nails - thinning of nail plate, ridging.
What drugs can cause lichen planus eruptions?
Gold
Quinine
Thiazides
What is the management of Lichen Planus?
Potent topical steroids
Benzydamine mouthwash
Extensive - oral steroids or immunosuppression.
What is Lichen sclerosus?
Inflammatory condition usually affecting the genitalia and more common in elder females. Leads to atrophy of the epidermis and white plaques forming.
What are the features of lichen sclerosus?
Itch
White lesions, typically on genitalia.
How is lichen sclerosus diagnosed?
Clinical grounds
Biopsy can be performed
What is the management of lichen sclerosus?
Topical steroids and emollients
What is a potential complication of lichen sclerosus?
Increased risk of vulval cancer
What is the differential diangosis for lichen sclerosus?
VIN or cancer
What are indications for a biopsy in lichen sclerosus?
Unsure diagnosis Suspicion of neoplastic change Poor response to treatment Extragenital LS Pigmented areas
What is a lipoma?
A common, benign tumour of adipocytes.
What is the pathophysiology of a lipoma?
Generally found in subcutaneous tissues
May occur in deeper tissues, malignant transformation to liposarcoma is rare.
What are the features of a lipoma?
Smooth, mobile, painless lump.
What is the management of a lipoma?
May be observed, if diagnosis uncertain or compressing on surrounding structures then may be removed.
What are the features of a liposarcoma?
Features suggestive or sarcomatous change: Size > 5cm Increasing size Pain Deep anatomical location
What are Milia?
Milia are small, benign, keratin-filled cysts that typically appear around the face. They may appear at any age but they are more common in newborns.
What is mycosis fungoides?
A rare form of T-cell lymphoma affecting the skin
What are the features of mycosis fungiodes?
Itchy, red patches
Lesions tend to be of different colours in contrast to eczema/psoriasis where there is greater homogenicity
What is nickel dermatitis?
A common cause of allergic contact dermatitis, type 4 hypersensitivity reaction.
How is nickel dermatitis diagnosed?
Skin patch test
What is Pellagra?
A disease caused by nicotinic acid deficiency
What are the features of pellagra?
Dermatitis (brown scaly rash)
Diarrhoea
Dementia, depression
Death if not treated
What are the causes of pellagra?
Isoniazid therapy
More common in alcoholics
What is Polymorphic eruption of pregnancy?
A pruritic condition associted with last trimester
Lesions in abdominal striae
Periumbilical area often spared
What is the management of polymorphic eruption of pregnancy?
Emollients
Mild potency topical steroids and oral steroids
What is porphyria cutanea tarda?
Most common hepatic porphyria.
Due to an inherited defect in uroporphyrinogen decarboxylase or caused by hepatocyte damage e.g. alcohol, hepatitis C, oestrogen.
What are the features of Porphyria cutanea tarda?
Photosensitive rash with blistering and skin fragility on the face and dorsal aspect of hands.
Hypertrichosis (excessive hair growth)
Hyperpigmentation
What are the investigations of porphyria cutanea tarda?
Urine: elevated uroporphyrinogen and pink fluorescence of urine under Wood’s lamp
Serum iron ferritin level is used to guide therapy
What is the management of porphyria cutanea tarda?
Chloroquine
Venesetion - preferred if iron ferritin is above 600 ng/ml
What is a port wine stain?
Vascular birthmarks, tend to be unilateral.
Deep red or purple in colour
What is the prognosis of port wine stain?
Do not spontaneously resolve, often darken and become raised over time.
What is the treatment of port wine stains?
Cosmetic camouflage
Laser therapy
What are the causes of pruritis?
Liver disease Iron deficiency anaemia Polycythaemia Chronic kidney disease Lymphoma Hyper/Hypothyroidism Diabetes Pregnancy 'Senile' pruritis Urticaria Skin disorders: eczema, scabies, psoriasis, pityriasis rosea
When pruritis is caused by liver disease, what other features may be present?
History of alcohol excess
Stigmata of chronic liver disease: spider naevi, bruising, palmar erythema, gynaecomastic.
Evidence of decompensation ascites, jaundice, encephalopathy.
When pruritis is caused by iron deficiency anaemia, what other features may be present?
Pallor
Other signs: kolionychia, atrophic glossitis, post-cricoid webs, angular stomatitis.
When pruritis is caused by polycythaemia, what other features may be present?
Pruritis - ‘after warm bath’
Ruddy complexion
Gout
Peptic ulcer disease
When pruritis is caused by chronic kidney disease, what other features may be present?
Lethargy & pallor
Oedema & weight gain
Hypertension
When pruritis is caused by lymphoma, what other features may be present?
Night sweats
Lymphadenopathy
Splenimegaly, hepatomegaly
Fatigue
What is pyoderma gangrenosum?
A rare condition causing large, painful sores (ulcers) to develop on the skin.
What are the features of pyoderma gangrenosum?
Typically on the lower limbs
Initially small red papule
Later deep, red, necrotic ulcer with a violeceous border
Systemic symptoms: fever, myalgia
What are the causes of pyoderma gangrenosum?
Idiopathic - 50% IBD: UC or Crohn's RA, SLE Myeloproliferative disorders Lymphoma, myeloid leukaemias Monoclonal gammopathy (IgA) Primary biliary cirrhosis
What is the management of pyoderma gangrenosum?
Oral steroids
Other immunosuppresive therapy e.g. ciclosporin and infliximab.
What is a pyogenic granuloma?
Relatively common benign skin lesion.
Eruptive haemangioma
What are the causes of pyogenic granuloma?
Unknown
Linked with trauma, pregnancy, common in young women
What are the features of pyogenic granuloma?
Most common on the head/neck, upper trunk and hands.
Initially small red/brown spot, rapidly progresses to form raised, red/brown lesions which are spherical in shape
Lesions may bleed profusely or ulcerate
What is the management of a pyogenic granuloma?
Those associated with pregnancy may spontaneously resolve
Others may persist, removal may include curettage, cauterisation, cryotherapy and excision.
Give and example of a retinoid and what it can be used in the treatment of?
Isotretinoin
Used in the treatment of severe acne.
2/3 of patients have long-term remission or cure following a course.
What are some of the adverse effects of isotretinoin?
Teratogenicity: 2 x forms of contraception Dry skin, eyes and lips/mouth Low mood Raised triglycerides Hair thinning Nose bleeds Intracranial hypertension c.i. tetracyclines Photosensitivity
What are salmon patches?
Salmon patches are a kind of vascular birthmark which can be seen in around half of newborn babies, they are pink and blotchy and found on the forehead, eyelids and nape.
Usually fade over time.
What is a sebaceous cyst?
Encompasses epidermoid and pilar cysts.
Due to proliferation of epidermal cells within the dermis.
Contain a punctum.
Excision of the cyst wall is necesssary to prevent recurrence.
What is seborrhoeic keratoses?
Benign epidermal skin lesions seen in older people
What are the features of seborrhoeic keratoses?
Large variation in colour from flesh to light-brown to black
Stuck-on appearance
Keratotic plugs may be seen on the surface
What is the management of seborrhoeic keratoses?
Reassurance that benign
Removal - curettage, cryosurgery, shave biopsy.
What are the differentials for Shin lesions?
Erythema nodosum
Pretibial myxoedema
Pyoderma gangrenosum
Necrobiosis lipoidica diabeticorum
What is erythema nodosum?
Swollen fat under the skin, causing red bumps and patches.
Symmetrical, erythematous, tender, nodules which head without scarring.
(Often on the shins)
What are the most common causes of erythema nodosum?
Streptococcal infection, sarcoidosis, inflammatory bowel disease and drugs (penicillins, sulphonamides, COCP)
What is pretibial myxoedema?
Symmetrical, erythmatous lesions seen in Graves’ disease
Shiny, orange peel skin
What is Necrobiosis Lipoidica Diabeticorum?
Shiny, painless areas of yellow/red skin typically on the shin of diabetics
Often associated with telangiectasia
What are the three key skin malignancies?
Basal cell carcinoma
Squamous cell carcinoma
Malignant Melanoma
What is Kaposi sarcoma?
Tumour of vascular and lymphatic endothelium
Purple cutaneous nodules
Associated with immunosuppresion and HIV related disease
What is a dermatofibroma?
Benign lesion
Firm elevated nodules
Usually a history of trauma
Lesion consists of histocytes, blood vessels and fibrotic changes
What skin disorders are associated with pregnancy?
Atopic eruption of pregnancy
Polymorphic eruption of pregnancy
Pemphigoid gestationis
What is atopic eruption of pregnancy?
Eczematous, itchy red rash.
No specific treatment is neeeded.
What is polymorphic eruption of pregnancy?
Pruritic condition assocaited with last trimester
Lesions appear in abdominal striae
Emolients, mild potency topical steroids, oral steroids
What is pemphigoid gestationis?
Pruritic blistering lesions
Often develop in peri-unbilical region, spreads to trunk, back, buttocks and arms.
Usually presents in 2-3rd treimester and rarely seen in 1st pregnancy
Oral corticosteroids are usually required
What skin disorders are associated with SLE?
Photosensitive 'butterfly' rash Discoid lupus Alopecia Livedo reticularis: net-like rash Characteristic nasolabial sparing
What are the skin types?
Fitzpatrick Classification
I: Never tans, always burns (often red hair, freckles, and blue eyes)
II: Usually tans, always burns
III: Always tans, sometimes burns (usually dark hair and brown eyes)
IV: Always tans, rarely burns (olive skin)
V: Sunburn and tanning after extreme UV exposure (brown skin, e.g. Indian)
VI: Black skin (e.g. Afro-Caribbean), never tans, never burns
What are spider naevi?
(Spider angiomas)
Describe a central red papule with surrounding capillaries.
Blanch upon pressure
Upper body.
How can spider naevi be differentiated from telangiectasia?
Pressing on them
Spider naevi fill from the centre
Twelangiectasia from the edge
What diseases are spider naevi seen in?
Liver disease
Pregnancy
COCP
(10-15% of people will have one or more, common in childhood)
What are strawberry naevus?
(Capillary haemangioma) are usually not present at birth but may develop rapidly in the fist month of life.
Erythmatous, raised and multilobed tumours.
Typically increase in size until around 6-9 months before regressing over next few years.
What infants are more likely to have a strawberry naevus?
10% white infants
Females
Premature
Mothers had chorionic villous sampling
What are the potential complications or strawberry naevus?
Mechanical e.g. obstructing visual fields or airway Bleeding Ulceration Thrombocytopaenia Cosmetic
What is the treatment of strawberry naevus if it is obstructive?
Propranolol
What is Tinea?
Dermatophyte fungal infections
Tinea capitis - scalp
Tinea corporis - trunk, legs or arms
Tinea pedis - feed
What is Tinea capitis?
Scalp ringworm
Cause of scarring alopecia mainly seen in children, if untreated a raised, pustular, spongy/boggy mass called a kerion may form.
What is tinea corporis?
Ringworm
Causes (Trichophyton species)
Well-defined annular, erythematous lesions with pustules and papules
What is the treatment of tine corporis (ringworm)?
Oral fluconazole
What is toxic epidermal necrolysis?
A potentially life-threatening skin disorder that is most commonly seen secondary to a drug reaction.
Skin appears a scalded appearance over an extensive area.
(TEN can be seen as severe end of a spectrum of skin disorders which includes erythema multiforme and SJS)
What are the features of toxic epidermal necrolysis?
Systemically unwell e.g. Pyrexia, tachycardia
Positive Nikolsky’s sign: epidermis separates with mild lateral pressure
What drugs are known to induce toxic epidermal necrolysis?
Phenytoin Sulphonamides Allopurinol Penicillins Carbamazepine NSAIDs
What is the management of toxic epidermal necrolysis?
Stop precipitating factor
Supportive care, often in ICE
Intravenous immunoglobulin has been shown to be effective and now is commonly used first-line
Other treatment options include: immunosuppressive agents (ciclosporin and cyclophosphamide), plasmapheresis
What are the large vessel vasculitides?
Temporal arteritis
Takayasu’s arteritis
What are the medium vessel vasculitidis?
Polyarteritis nodosa
Kawasaki disease
What are the small vessel vasculitides?
ANCA-associated vasculitides (Wegener’s, Churg-Strauss, microscopic polyangiitis)
Henoch-Schonlein purpura
Cryoglobulinaemic vasculitis
Where is venous ulceration most typically seen?
Above the medial malleolus
What are the investigations of leg ulcers?
Ankle-brachial pressure index (ABPI)
A ‘normal’ ABPI may be regarded as between 0.9-1.2
What is the management of venous leg ulcers?
Compression bandaging
Oral pentoxifylline
How can the rash seen in acne rosacea differentiate from the rash seen in SLE?
In SLE papules and pustules are rarely seen but in AR they are common
What antibody is most likely to be seen in dermatitis herpetiformis?
Anti-tissue transglutaminase antibody
Assocaited with coeliac disease
