Dermatology Flashcards
What is CREST syndrome?
Systemic scleroderma
Calcinosis (calcium lumps under skin on fingers), Raynaud’s disease, (O)Esophageal dysmotility, Sclerodactyly, Telangiectasia
What is seborrheic keratosis?
Start as small rough areas, over time develop thick wart like surface, waxy, scaly elevated appearance
Usually brown, can be difficulty to distinguish from melanoma
What is actinic keratosis?
Dry scaly patches of skin caused by sun damage
Pink, red or brown, skin thickening, can look like horns
Can develop into SCC if not treated
Seen in fair skinned people
What are gottrons patches?
Scaly erythematous eruptions or red patches overlying the knuckles, elbows and knees
Characteristic of dermatomyositis
Describe features of psoriasis and its epidemiology
Pink scaly plaques, particularly on extensor surfaces which may be itchy and sore
Equally affects males and females
Two peaks of ages of onset: early onset 16-22, late onset 55-60
What are first line treatments for psoriasis?
Topical agents: emollients, steroids, calcipotriol, retinoids, purified coal tar
Phototherapy
Systemic therapy: methotrexate
An anxious 19 year old woman presents with a pigmented lesion on her left inner thigh. There is no significant past medical or family history. Inspection reveals a brown purple lesion of approximately 1cm diameter with a raised smooth surface. What is the likely diagnosis?
Dermatofibroma - benign skin lesion found especially on the legs
What is a Marjolins ulcer?
Squamous cell carcinoma developing in areas of chronic inflammation such as burn sites or varicose ulcers
A 68 year old woman is referred with an ulcerated lesion on the side of her nose. It was first noticed 4 months prior to presentation and had been slowly growing. Prior to that there was crusting of the skin which had been present for some years. Inspection reveals 12mm ulcer with raised everted edge. No lymph nodes are palpable. What is the likely diagnosis? What was the crusty lesion described before it developed?
Squamous cell carcinoma
Pre lesion - actinic keratosis
What are predisposing factors for squamous cell carcinoma?
Sun exposure
Radiation exposure
Pre malignant conditions: bowens, senile keratosis, lupus vulgaris, Paget’s disease
Inherited: xeroderma pigmentosum, albinism
Chronic irritation: Marjolins ulcer, leukoplakia, varicose veins, osteomyelitis sinus
Infection: HPV 5 and 8
What is xeroderma pigmentosum?
Hereditary defect of enzyme system that repairs DNA after UV damage resulting in extreme sensitivity to sunlight and a tendency to develop skin cancer
What is lupus vulgaris?
Chronic direct infection of the skin with TB causing dark red patches with a nodular appearance, often around the face and neck
What is leukoplakia?
White patch in the mouth - area of keratosis
What is lichen planus?
Disease of skin and/or mucus membranes that resembles lichen
Autoimmune process
Who is most likely to get psoriasis and at what age?
Males and females equally likely
Peaks of onset: 16-22 and 55-60
What is pemphigoid?
Autoimmune blistering condition characterised by development of bullous like lesions which typically develop on the lower limb
What is erythema nodosum?
Raised erythematous lesions on shins
Associated with drugs - sulphonamides, oral contraceptives and penicillins
Associated with infections - mycoplasma pneumonia, RA and sarcoidosis
What is pre tibial myxoedema?
Waxy discoloured induration of skin - orange peel
Occurs in graves, Hashimoto’s and stasis dermatitis
How does a basal cell carcinoma typically present?
Small pink coloured nodule or papule with visible surface telangiectasia and pearly rolled edges
What is erysipelas?
Acute episode of cellulitis
What are 3 causes for erythema nodosum?
Inflammatory bowel disease
Sarcoidosis
Pregnancy
How does erythema multiforme present?
Acute inflammatory condition often precipitated by herpes simplex
Tender nodules surrounded by page rings - target
Give 5 features of a lesion which make you suspect skin cancer
Change in size Change in shape Change in colour Bleeding Sensory change
Name 2 features of an examination that would make you suspect a basal cell carcinoma
Pearly nodule with rolled telangiectatic edge
Ulcer
Where would you look for secondary spread in a basal cell carcinoma?
Regional lymph nodes
Name 3 treatments for basal cell carcinoma
Excision
Cryotherapy and curettage
Radiotherapy
Name 1 feature of the examination of a basal cell carcinoma which would narrow the treatment options available
Size
What is pyoderma gangrenosum associated with?
Rheumatoid arthritis
Inflammatory bowel disease
Paraproteinaemia
A 64 year old woman is referred by her GP with an itchy red brown lesion on her cheek. It has been present for many months and has been growing slowly. On examination there is a 1 X 0.5cm lesion with a crusty surface. There are no other lesions and there is no lymphadenopathy. What is the diagnosis?
Bowens disease
What is the main risk factor for bowens disease?
UV exposure
A 45 year old woman is referred for a lesion on her cheek. On examination it is raised above the level of the surrounding skin, has an irregular surface with smooth sides, central umbilication and a crusty core. What is it?
Keratoacanthoma: hyperplasia of hair follicles
A 70 year old woman is referred with a 3 X 2cm pigmented brown black lesion on her right temple. On examination the lesion has an irregular edge but a smooth flat surface. No lymphadenopathy is palpable. What is it?
Lentigo maligna: melanoma in situ
A 34 year old male IV drug user is seen in the clinic with several new red brown nodules on his limbs. He has also recently been treated for an opportunistic pneumonia and his prescription includes AZT. What does he have?
Kaposis sarcoma: manifestation of HIV infection
64 year old man referred with an itchy pigmented lesion on his cheek which has recently changed size and shape. On examination the lesion has an irregular edge and raised surface with variable pigmentation. There is a surface clot following a recent contact bleed. What is the likely diagnosis?
Nodular melanoma
Anxious 19 year old woman presents with pigmented lesion on left inner thigh. No past medical or family Hx. Inspection reveals a brown purple lesion of 1cm diameter with a raised smooth surface. What is the likely diagnosis?
Dermatofibroma
What is a pyogenic granuloma?
Hands and face of children and young adults
Lesions on lips and gums of pregnant women
Benign capillary haemangiomas
What is the other name for neurofibromatosis?
Von recklinghausens disease
What features of a leg ulcer would make you think it is venous?
Warm Oedematous Eczematous Haemosiderin deposits Lipodermatosclerosis Atrophie Blanche
What features of a leg ulcer would make you think it is arterial?
Pale Shiny Hairless Cold skin Painful especially when elevated in bed
What ankle brachial plexus index values would you be worried about?
1.2 arterial calcification
What are the different types of melanoma?
Nodular
Superficial spreading
Lentigo maligna
Acral lentiginous
What are risk factors for developing malignant melanoma?
More than 5 episodes of sunburn under age of 10
>100 naevi
Atypical naevus syndrome
Personal and/or family history of melanoma
Large congenital melanocytic naevus
Skin type 1: tending to burn easily and not tan in the sun
How do you manage a superficial spreading malignant melanoma?
Excise with a 2mm clinical margin to confirm diagnosis
Wider excision will be required, margin depending on thickness of the tumour
What is an important risk factor for recurrence of a malignant melanoma?
Breslow thickness: depth of tumour, measured on histology in millimetres from granular cell layer to deepest point of tumour
What can be triggers for erythema nodosum?
Streptococcal throat infection TB Leprosy Chlamydia Sarcoidosis IBD Pregnancy Malignancy Drugs: contraceptive pill, sulphonamides
What factors can be used to prevent the recurrence of venous leg ulcers?
Compression stockings
Keeping legs elevated
Avoidance of trauma to skin
What are causes of urticaria?
Idiopathic Allergy to food Insect bites Drug induced Infections Physical: pressure, sunlight, cold
What can cause reactivation of quiescent herpes simplex virus?
Stress
Trauma
Febrile illness
UV radiation
What are complications of hsv 1 infection?
Eye infection: Dendritic ulceration, Keratitis
Acute encephalitis
Skin infections: herpetic whitlow, erythema multiforme
What is the koebner phenomenon?
Tendency for skin disorders to appear at the sites of trauma
What are signs of secondary syphilis?
Generalised lymphadenopathy
Skin rashes including palms and soles
Condylomata lata: warty plaque like lesions in perianal area
Superficial confluent ulceration of mucosal surfaces: snail track ulcers
What is a gumma?
Soft, non-cancerous growth resulting from the tertiary stage of syphilis
A form of granuloma
Firm, necrotic center surrounded by inflamed tissue, which forms an amorphous proteinaceous mass
What are the 6 Ps of lichen planus?
Planar (flat-topped) Purple Polygonal Pruritic Papules Plaques
What must be excluded in men with balanoposthitis?
Diabetes
What are differences between pemphigus and pemphigoid?
Both characterised by bullae
Pemphigus vulgaris: autoantibodies against epidermal cell junctions, flaccid bullae that burst easily
Bullous pemphigoid: autoantibodies against basement membrane of epidermis, subepidermal bullae, less fragile, tense
What is impetigo?
Highly infectious skin disease common in children
Weeping exudative area with honey coloured crust
Spread by direct contact
Staph or group A beta haemolytic strep
What is the treatment for impetigo?
Flucloxacillin for staph
Phenoxymethylpenicillin for strep
Avoid school for 1 week
What is the difference between bullous impetigo and staph scalded skin syndrome?
Toxin A: bullous impetigo, localised
Toxin B: staph scalded skin syndrome, spreads throughout body
What causes viral warts?
Human papilloma virus
What can you use to treat a viral wart?
Topical keratolytic agent: salicylic acid
Cryotherapy
What is molluscum contagiosum?
Pox virus
Multiple small translucent Papules which look fluid filled but are actually solid
Central punctum
Can occur at any site including genitals
Continue to occur in crops over 6-12 months
What is orf?
Disease of sheep due to a pox infection
Vesicular and pustular rash
People who have come into contact with fluid may develop lesions on hands
1-2cm reddish Papules with surrounding erythema which usually become pustular
What can be a complication of orf?
Erythema multiforme
Describe the lesion seen in tinea corporis
Ringworm of body
Asymmetrical scaly patches which show central clearing and an advancing scaly raised edge
Describe the lesion seen in Candida albicans
Red ragged peeling edge that may contain a few small pustules
Small circular areas of erythema or small Papules and pustules may be seen in front of the advancing edge - satellite lesions
Mouth/genitals: superficial white or creamy pseudomembranous plaques
How does atopic eczema present?
Itchy erythematous scaly patches especially in flexures and around neck
In infants, usually starts on face and spreads to the body
Acute lesions may weep or exude and can show small vesicles
Scratching produces excoriations
Repeated rubbing produces lichenification - skin thickening
What are complications of atopic eczema?
Staph aureus infection: crusted weeping impetigo like lesions
Cutaneous viral infections: viral warts and molluscum
HSV: eczema herpeticum
Conjunctival irritation
Keratoconjunctivitis
Cataract
Retarded growth
What are treatments for atopic eczema?
Avoiding known irritants
Wearing cotton clothes
Not getting too hot
Triple combination: topical steroid, frequent emollients and bath oil and soap substitute (aqueous cream)
What is seborrhoeic eczema?
Overgrowth of pityrosporum and strong immune reaction to this yeast produces inflammation and scaling
Who is most likely to get seborrhoeic eczema?
Parkinson’s
HIV
Neonates: cradle cap
What is the treatment for seborrhoeic eczema?
Mild steroid ointment
Topical anti fungal: miconazole
What are the different types of psoriasis?
Chronic plaque Flexural Guttate Erythrodermic Pustular
What can be used to treat psoriasis?
Emollients Topical steroids Vitamin D3 analogues: calcipotriol, calcitriol Tazarotene (retinoid) Purified coal tar
What do erythema multiforme lesions look like? And what typically causes it?
Target lesions
Herpes virus
What is nikolskys sign?
Epidermal layer sloughs off when pressure is applied
What can maternal infection with rubella cause during pregnancy?
Spontaneous abortion
Foetal death
Congenital abnormalities
What signs and symptoms might a patient with rubella have?
Fever Maculopapular rash Lymphadenopathy Conjunctivitis Arthritis
What are some potential complications of measles?
Pneumonia
Laryngotracheitis
Otitis media
Encephalitis
What are risk factors for pressure sore development?
Prolonged immobility Poor nutrition Vascular disease Sensory loss Age Incontinence
What needs to be done before commencing oral retinoid therapy?
Pregnancy test
Contraceptive advice
Signed consent
Monthly pregnancy test
What characteristics of a lesion would make you think it is seborrhoeic keratosis?
Older age group Face scalp and trunk Warty surface Stuck on appearance Matte surface Multiple lesions Shiny keratin cysts Comedo like openings
What characteristics of a lesion would make you think it is a benign mole?
Longstanding Hasn't changed Regular borders Well defined Only one colour Symmetrical Small
What are risk factors for venous ulcer development?
PVD
Varicose veins
Venous hypertension: DVT, valvular incompetence
What are risk factors for developing arterial ulcers?
Smoking High cholesterol Hypertension IHD Age Diabetes Obesity
What monitoring should be done for a patient on long term azathioprine?
FBC and U and Es every 3 months
