Dermatology Flashcards

(119 cards)

1
Q

Causes of acanthosis nigricans

A

type 2 diabetes mellitus
Addisons disease
gastrointestinal cancer
obesity
polycystic ovarian syndrome
acromegaly
Cushing’s disease
hypothyroidism
familial
Prader-Willi syndrome
drugs- combined oral contraceptive pill, nicotinic acid

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2
Q

Typical features of acne vulgaris

A

Comedones are due to a dilated sebaceous follicle
-if the top is closed a whitehead is seen
-if the top opens a blackhead forms

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3
Q

Inflammatory changes seen in acne vulgaris

A

papules
pustules

An excessive inflammatory response may result in:

nodules
cysts

NB- eventually scars may form eg. ice pick scars, hypertrophic scars

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4
Q

Management of acne vulgaris

A

Mild- benzoyl peroxide, topical antibiotics, and topical retinoids
Moderate- oral antibiotics, and anti-androgens (in females) eg. COCT (Dianette- risk of VTE)
Severe- oral retinoids (eg. isoretinoin)

NB- ABX of choice: tetracyclines: lymecycline, oxytetracycline, doxycycline (erythromycin in pregnancy, breastfeeding, children under 12)

NB- pregnancy is contraindicated to oral or topical retinoids

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5
Q

Actinic keratoses

A

Pre-malignant skin lesions that form as a result of chronic sun exposure;

small, crusty or scaly, lesions
may be pink, red, brown or the same colour as the skin
typically on sun-exposed areas e.g. temples of head
multiple lesions may be present

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6
Q

Management of actinic keratoses

A

Lifestyle- sun avoidance, sun cream
Medical- fluorouracil cream (sometimes topical hydrocortisone is given following fluorouracil to help settle the inflammation), topical diclofenac, topical imiquimod, cryotherapy
Surgery- curettage and cautery

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7
Q

BCC

A

Most common cancer in the Western world

many types of BCC are described. The most common type is nodular BCC, which is described here
sun-exposed sites, especially the head and neck account for the majority of lesions
initially a pearly, flesh-coloured papule with telangiectasia
may later ulcerate leaving a central ‘crater’

Management;
surgical removal
curettage
cryotherapy
topical cream: imiquimod, fluorouracil
radiotherapy

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8
Q

Bowens disease

A

Bowen’s disease is a type of precancerous dermatosis that is a precursor to squamous cell carcinoma. It is more common in elderly patients. There is around a 5-10% chance of developing invasive skin cancer if left untreated.

red, scaly patches
often 10-15 mm in size
slow-growing
often occur on sun-exposed areas such as the head (e.g. temples) and neck, lower limbs

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9
Q

Management of Bowens disease

A

-may sometimes be diagnosed and managed in primary care if clear diagnosis or repeat episode
-topical 5-fluorouracil (typically used twice daily for 4 weeks, often results in significant inflammation/erythema. Topical steroids are often given to control this)
-cryotherapy
-excision

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10
Q

Bullous Pemphigoid

A

An autoimmune condition causing sub-epidermal blistering of the skin.

itchy, tense blisters typically around flexures
the blisters usually heal without scarring
there is usually no mucosal involvement (i.e. the mouth is spared)*

investigation- immunofluorescence shows IgG and C3 at the dermoepidermal junction

Management- refer to dermatology, oral steroids and immunosuppressants, also oral steroids and ABX

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11
Q

Assessing extent of a burn

A

Lund and Browder chart: the most accurate method

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12
Q

Which burns are referred to secondary care

A

all deep dermal and full-thickness burns.
superficial dermal burns of more than 3% TBSA in adults, or more than 2% TBSA in children
superficial dermal burns involving the face, hands, feet, perineum, genitalia, or any flexure, or circumferential burns of the limbs, torso, or neck
any inhalation injury
any electrical or chemical burn injury
suspicion of non-accidental injury

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13
Q

Initial burn management

A

superficial epidermal: symptomatic relief - analgesia, emollients etc
superficial dermal: cleanse wound, leave blister intact, non-adherent dressing, avoid topical creams, review in 24 hours
severe/full thickness: IV fluids, stabilise airway, escharotomy/plastics input

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14
Q

Cherry haemangioma

A

erythematous, papular lesions
typically 1-3 mm in size
non-blanching
not found on the mucous membranes

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15
Q

Chronic plaque psoriasis

A

Chronic plaque psoriasis is the most common form of psoriasis seen in clinical practice, accounting for around 80% of presentations.

erythematous plaques covered with a silvery-white scale
typically on the extensor surfaces such as the elbows and knees. Also common on the scalp, trunk, buttocks and periumbilical area
clear delineation between normal and affected skin
plaques typically range from 1 to 10 cm in size
if the scale is removed, a red membrane with pinpoint bleeding points may be seen (Auspitz’s sign)
50% have associated nail changes (e.g. pitting, onycholysis)

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16
Q

Contact dermatitis

A

irritant contact dermatitis: common - non-allergic reaction due to weak acids or alkalis (e.g. detergents). Often seen on the hands. Erythema is typical, crusting and vesicles are rare

allergic contact dermatitis: type IV hypersensitivity reaction. Uncommon - often seen on the head following hair dyes. Presents as an acute weeping eczema which predominately affects the margins of the hairline rather than the hairy scalp itself. Topical treatment with a potent steroid is indicated

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17
Q

Dermatitis herpetiformis

A

An autoimmune blistering skin disorder associated with coeliac disease. It is caused by deposition of IgA in the dermis.

Features- itchy, vesicular skin lesions on the extensor surfaces (e.g. elbows, knees, buttocks) and abdomen

Diagnosis- skin biopsy: direct immunofluorescence shows deposition of IgA in a granular pattern in the upper dermis

Management
-gluten-free diet
-dapsone

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18
Q

Deramtofibroma

A

solitary firm papule or nodule, typically on a limb
typically around 5-10mm in size
overlying skin dimples on pinching the lesion

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19
Q

Eczema herpeticum

A

Eczema herpeticum describes a severe primary infection of the skin by herpes simplex virus 1 or 2.

It is more commonly seen in children with atopic eczema and often presents as a rapidly progressing painful rash.

On examination, monomorphic punched-out erosions (circular, depressed, ulcerated lesions) usually 1–3 mm in diameter are typically seen. May have itchy vesicles that contain pus. May have lymphadenopathy

As it is potentially life-threatening children should be admitted for IV aciclovir.

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20
Q

Erysipelas

A

Erysipelas is localised skin infection caused by Streptococcus pyogenes. In simple terms, it is a more superficial, limited version of cellulitis.

The treatment of choice is flucloxacillin.

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21
Q

Erythema ab igne

A

Erythema ab igne is a skin disorder caused by over exposure to infrared radiation. Characteristic features include reticulated, erythematous patches with hyperpigmentation and telangiectasia. A typical history would be an elderly women who always sits next to an open fire.

If the cause is not treated then patients may go on to develop squamous cell skin cancer.

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22
Q

Erythema multiforme

A

a hypersensitivity reaction which is most commonly triggered by infections. It may be divided into minor and major forms.

Causes;
viruses: herpes simplex virus (the most common cause), Orf
idiopathic
bacteria: Mycoplasma, Streptococcus
drugs: penicillin, sulphonamides, carbamazepine, allopurinol, NSAIDs, oral contraceptive pill, nevirapine
connective tissue disease e.g. Systemic lupus erythematosus
sarcoidosis
malignancy

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23
Q

Features of erythema multiforme

A

target lesions
initially seen on the back of the hands / feet before spreading to the torso
upper limbs are more commonly affected than the lower limbs
pruritus is occasionally seen and is usually mild

NB- the more severe form, erythema multiforme major is associated with mucosal involvement.

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24
Q

Erythema nodosum

A

inflammation of subcutaneous fat
typically causes tender, erythematous, nodular lesions
usually occurs over shins, may also occur elsewhere (e.g. forearms, thighs)
usually resolves within 6 weeks
lesions heal without scarring

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25
Causes of erythema nodusum
infection -streptococci -tuberculosis -brucellosis systemic disease -sarcoidosis (with raised calcium) -inflammatory bowel disease -Behcet's malignancy/lymphoma drugs -penicillins -sulphonamides -combined oral contraceptive pill pregnancy NB- IBD and sarcoid most common
26
Erythrasma
Erythrasma is a generally asymptomatic, flat, slightly scaly, pink or brown rash usually found in the groin or axillae. It is caused by an overgrowth of the diphtheroid Corynebacterium minutissimum Examination with Wood's light reveals a coral-red fluorescence. Topical miconazole or antibacterial are usually effective. Oral erythromycin may be used for more extensive infection
27
Erythroderma
Erythroderma is a term used when more than 95% of the skin is involved in a rash of any kind. Causes of erythroderma; eczema psoriasis drugs e.g. gold lymphomas, leukaemias idiopathic
28
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 more serious form is an acute deterioration. This may be triggered by a variety of factors such as withdrawal of systemic steroids. Patients need to be admitted to hospital for management
29
Guttate psoriasis
Guttate psoriasis is more common in children and adolescents. It may be precipitated by a streptococcal infection 2-4 weeks prior to the lesions appearing. Features; tear drop papules on the trunk and limbs gutta is Latin for drop pink, scaly patches or plques of psoriasis tends to be acute onset over days
30
Management of guttate psoriasis
most cases resolve spontaneously within 2-3 months there is no firm evidence to support the use of antibiotics to eradicate streptococcal infection topical agents as per psoriasis UVB phototherapy tonsillectomy may be necessary with recurrent episodes
31
Onychomycosis
fungal infection of the nails Risk factors include for fungal nail infections include diabetes mellitus and increasing age. Features -'unsightly' nails are a common reason for presentation -thickened, rough, opaque nails are the most common finding Differential diagnosis; psoriasis repeated trauma lichen planus yellow nail syndrome Investigation; nail clippings scrapings of the affected nail
32
Management of fungal nail infections
Asymptomatic and not bothered- no treatment dermatophyte infection (Trichophyton rubrum)- oral terbinafine is currently recommended first-line with oral itraconazole as an alternative. 6 weeks - 3 months therapy is needed for fingernail infections whilst toenails should be treated for 3 - 6 months. treatment is successful in around 50-80% of people Candida infection- mild disease should be treated with topical antifungals (e.g. Amorolfine) whilst more severe infections should be treated with oral itraconazole for a period of 12 weeks NB- ine's are first line, oral itraconazole second line NB- T for T, terbinafine for trichophyton
32
HHT
an autosomal dominant condition characterised by (as the name suggests) multiple telangiectasia over the skin and mucous membranes. Twenty percent of cases occur spontaneously without prior family history. epistaxis : spontaneous, recurrent nosebleeds telangiectases: multiple at characteristic sites (lips, oral cavity, fingers, nose) visceral lesions: for example gastrointestinal telangiectasia (with or without bleeding), pulmonary arteriovenous malformations (AVM), hepatic AVM, cerebral AVM, spinal AVM NB- usually have a positive FH
33
Hidradenitis suppurativa
a chronic, painful, inflammatory skin disorder. It is characterized by the development of inflammatory nodules, pustules, sinus tracts, and scars in intertriginous areas. It should be suspected in pubertal or post-pubertal patients who have a diagnosis of recurrent furuncles or boils, especially in intertriginous areas.
34
Management of Hidradenitis suppurativa
Lifestyle- Encourage good hygiene and loose-fitting clothing, Smoking cessation, Weight loss in obese Acute flares can be treated with steroids (intra-lesional or oral) or flucloxacillin. Surgical incision and drainage may be needed in some cases. Long-term disease can be treated with topical (clindamycin) or oral (lymecycline or clindamycin and rifampicin) antibiotics. Lumps that persist despite prolonged medical treatment are excised surgically.
35
Hirsutism (women)
androgen-dependent hair growth in women (ie. specific to androgenous regions ie. face, chin, axillae, pubis etc.) Polycystic ovarian syndrome Cushing's syndrome congenital adrenal hyperplasia androgen therapy obesity: thought to be due to insulin resistance adrenal tumour androgen secreting ovarian tumour drugs: phenytoin, corticosteroids
36
Hypertrichosis (women and men)
androgen-independent hair growth (ie. not specific to androgenous regions ie. whole body) drugs: minoxidil, ciclosporin, diazoxide congenital hypertrichosis lanuginosa, congenital hypertrichosis terminalis porphyria cutanea tarda anorexia nervosa
37
Management of hirsutism
advise weight loss if overweight combined oral contraceptive pill facial hirsutism: topical eflornithine - contraindicated in pregnancy and breast-feeding
38
Hyperhidrosis
Excessive sweating topical aluminium chloride preparations are first-line. Main side effect is skin irritation iontophoresis: particularly useful for patients with palmar, plantar and axillary hyperhidrosis botulinum toxin: currently licensed for axillary symptoms surgery: e.g. Endoscopic transthoracic sympathectomy. Patients should be made aware of the risk of compensatory sweating
39
Impetigo
a superficial bacterial skin infection usually caused by either Staphylcoccus aureus or Streptococcus pyogenes. It can be a primary infection or a complication of an existing skin condition such as eczema, scabies or insect bites (common in children) 'golden', crusted skin lesions typically found around the mouth very contagious Management; conservative- children should be excluded from school until the lesions are crusted and healed or 48 hours after commencing antibiotic treatment Localised- hydrogen peroxide 1% cream, topical fuscidic acid if unable Severe- oral flucloxacillin (erythromycin)
40
Keloid scars
tumour-like lesions that arise from the connective tissue of a scar and extend beyond the dimensions of the original wound Predisposing factors; ethnicity: more common in people with dark skin occur more commonly in young adults, rare in the elderly common sites (in order of decreasing frequency): sternum, shoulder, neck, face, extensor surface of limbs, trunk Treatment; early keloids may be treated with intra-lesional steroids e.g. triamcinolone excision is sometimes required
41
Keratocathoma
Keratoacanthoma is a benign epithelial tumour. They are more common with advancing age and rare in young people. Features - said to look like a volcano or crater initially a smooth dome-shaped papule rapidly grows to become a crater centrally-filled with keratin Spontaneous regression of keratoacanthoma within 3 months is common, often resulting in a scar. Such lesions should however be urgently excised as it is difficult clinically to exclude squamous cell carcinoma. Removal also may prevent scarring.
42
Ketoconazole
Due to the high risk of hepatic toxicity (ranging from hepatitis to cirrhosis/liver failure) it advised against the use of oral ketoconazole completely. This does not affect the prescription of topical ketoconazole
43
Koebner phenomenon
The Koebner phenomenon describes skin lesions that appear at the site of injury. It is seen in: psoriasis vitiligo warts lichen planus
44
Leukoplakia
a premalignant condition which presents as white, hard spots on the mucous membranes of the mouth. It is more common in smokers. Biopsies are usually performed to exclude alternative diagnoses such as squamous cell carcinoma and regular follow-up is required to exclude malignant transformation to squamous cell carcinoma, which occurs in around 1% of patients.
45
Lichen planus
itchy, papular rash most common on the palms, soles, genitalia and flexor surfaces of arms rash often polygonal in shape, with a 'white-lines' pattern on the surface (Wickham's striae) Koebner phenomenon may be seen (new skin lesions appearing at the site of trauma) oral involvement in around 50% of patients: typically a white-lace pattern on the buccal mucosa nails: thinning of nail plate, longitudinal ridging Planus (P's)- purple, pruritic, papular, polygonal rash on flexor surfaces. Wickham's striae over surface. Oral involvement common Lichenoid drug eruptions - causes: -gold -quinine -thiazides
46
Management of lichen planus
topical steroids benzylamine mouthwash or spray is recommended for oral lichen planus extensive lichen planus- oral steroids or immunosuppression
47
Lichen sclerosus
an inflammatory condition that usually affects the genitalia and is more common in elderly females. Lichen sclerosus leads to atrophy of the epidermis with white plaques forming Features; white patches that may scar itch is prominent may result in pain during intercourse or urination Management- topical steroids and emollients (biopsy if it doesn't respond) NB- increased risk of vulval cancer
48
Lipoma
Benign tumour of adipocytes smooth mobile painless Usually not treated- if diagnosis uncertain, or compressing on surrounding structures then may be removed
49
Liposarcoma
Very rare for lipomas to undergo malignant transformation Features suggestive of sarcomatous change: Size >5cm Increasing size Pain Deep anatomical location
50
Types of melanoma
Superficial spreading- A growing mole Nodular- Red or black lump or lump which bleeds or oozes (worst prognosis) Lentigo maligna- A growing mole Acral lentiginous- Subungual pigmentation (Hutchinson's sign) or on palms or feet
51
Diagnostic features of melanoma
The main diagnostic features (major criteria): -Change in size -Change in shape -Change in colour Secondary features (minor criteria) -Diameter >= 7mm -Inflammation -Oozing or bleeding -Altered sensation The ‘ABCDE Symptoms’ rule (*major suspicious features): Asymmetrical shape* Border irregularity Colour irregularity* Diameter > 6mm Evolution of lesion (e.g. change in size and/or shape)* Symptoms (e.g. bleeding, itching)
52
Management of melanoma
Suspicious lesions should undergo excision biopsy. The lesion should be removed in completely as incision biopsy can make subsequent histopathological assessment difficult. Once the diagnosis is confirmed the pathology report should be reviewed to determine whether further re-excision of margins is required
53
Malignant melanoma prognostic factors
The invasion depth of a tumour (Breslow depth) is the single most important factor in determining prognosis of patients with malignant melanoma
54
Molluscum contagiosum
a common skin infection caused by molluscum contagiosum virus Transmission occurs directly by close personal contact, or indirectly via fomites The majority of cases occur in children
55
Features of molluscum contagiosum
characteristic pinkish or pearly white papules with a central umbilication, which are up to 5 mm in diameter Lesions appear in clusters in areas anywhere on the body (except the palms of the hands and the soles of the feet). In children, lesions are commonly seen on the trunk and in flexures, but anogenital lesions may also occur. In adults, sexual contact may lead to lesions developing on the genitalia, pubis, thighs, and lower abdomen. Rarely, lesions can occur on the oral mucosa and on the eyelids.
56
Management of molluscum contagiosum
Lifestyle- self-limiting and should resolve in 18 months, don't scratch, contagious so don't share towels etc. Medical- usually not required, but may be pierced, cryotherapy, or emollient with steroid if itching
57
Referral for molluscum contagiosum
For people who are HIV-positive with extensive lesions urgent referral to a HIV specialist For people with eyelid-margin or ocular lesions and associated red eye urgent referral to an ophthalmologist Adults with anogenital lesions should be referred to genito-urinary medicine, for screening for other sexually transmitted infections
58
Mycosis fungoides
a rare form of T-cell lymphoma that affects the skin. Features; itchy, red patches which are lesions tend to be of different colours in contrast to eczema/psoriasis where there is greater homogenicity
59
Mycosis fungoides
a rare form of T-cell lymphoma that affects the skin. Features; itchy, red patches which are lesions tend to be of different colours in contrast to eczema/psoriasis where there is greater homogenicity
60
Pellagra
caused by nicotinic acid (niacin, B3) deficiency. The classical features are the 3 D's - dermatitis (around the neck), diarrhoea and dementia. Pellagra may occur as a consequence of isoniazid therapy (isoniazid inhibits the conversion of tryptophan to niacin) and it is more common in alcoholics.
61
Pemphigus vulgaris
an autoimmune disease. It is more common in the Ashkenazi Jewish population. mucosal ulceration is common and often the presenting symptom. Oral involvement is seen in 50-70% of patients skin blistering - flaccid, easily ruptured vesicles and bullae. Lesions are typically painful but not itchy. These may develop months after the initial mucosal symptoms. Nikolsky's describes the spread of bullae following application of horizontal, tangential pressure to the skin acantholysis on biopsy Management- steroids, then immunosuppressants
62
Perioral dermatitis
a condition typically seen in women aged 20-45 years old. Topical corticosteroids, and to a lesser extent, inhaled corticosteroids are often implicated in the development of the condition. Features; clustered erythematous papules, papulovesicles and papulopustules most commonly in the perioral region but also the perinasal and periocular region Management; steroids may worsen symptoms should be treated with topical or oral antibiotics
63
Pityriasis rosea
an acute, self-limiting rash which tends to affect young adults. The aetiology is not fully understood but is thought that herpes hominis virus 7 (HHV-7) may play a role. Features; a minority may give a history of a recent viral infection herald patch (usually on trunk) followed by erythematous, oval, scaly patches which follow a characteristic distribution with the longitudinal diameters of the oval lesions running parallel to the line of Langer ('fir-tree' appearance) NB- usually disappears after 6-12 weeks
64
Pityriasis (tinea) versicolour
a superficial cutaneous fungal infection caused by Malassezia furfur (formerly termed Pityrosporum ovale) Features; most commonly affects trunk patches may be hypopigmented, pink or brown (hence versicolor). May be more noticeable following a suntan scale is common mild pruritus Predisposing factors; occurs in healthy individuals immunosuppression malnutrition Cushing's
65
Management of pityriasis versicolour
topical antifungal- ketoconazole shampoo if failure to respond to topical treatment then consider alternative diagnoses (e.g. send scrapings to confirm the diagnosis) + oral antifungal eg. itraconazole
66
Polymorphic eruption of pregnancy
pruritic condition associated with the last trimester lesions often first appear in abdominal striae the periumbilical area is often spared management depends on severity: emollients, mild potency topical steroids and oral steroids may be used NB- Atopic eruption of pregnancy is the commonest skin disorder found in pregnancy it typically presents as an eczematous, itchy red rash.
67
Pompholyx
a type of eczema which affects both the hands and the feet Pompholyx eczema may be precipitated by humidity (e.g. sweating) and high temperatures. Features; small blisters on the palms and soles pruritic often intensely itchy sometimes burning sensation once blisters burst skin may become dry and crack Management; cool compresses emollients topical steroids
68
Porphyria cutanea tarda
classically presents with photosensitive rash with blistering and skin fragility on the face and dorsal aspect of hands (most common feature) hypertrichosis hyperpigmentation Investigations; urine: elevated uroporphyrinogen and pink fluorescence of urine under Wood's lamp serum iron ferritin level is used to guide therapy Management; chloroquine venesection
69
Causes of pruritis
Liver disease Post stroke priritus Iron deficiency anaemia Polycythaemia CKD Lymphoma hyper- and hypothyroidism diabetes pregnancy 'senile' pruritus urticaria skin disorders: eczema, scabies, psoriasis, pityriasis rosea
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Nail changes and psoriasis
pitting onycholysis (separation of the nail from the nail bed) subungual hyperkeratosis loss of the nail NB- 90% people with psoriatic arthritis have nail changes
71
Exacerbation of psoriasis
trauma alcohol drugs: beta blockers, lithium, antimalarials (chloroquine and hydroxychloroquine), NSAIDs and ACE inhibitors, infliximab withdrawal of systemic steroids Streptococcal infection may trigger guttate psoriasis.
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Causes of purpura in children
Meningococcal septicaemia • Acute lymphoblastic leukaemia • Congenital bleeding disorders • Immune thrombocytopenic purpura • Henoch-Schonlein purpura • Non-accidental injury DIC
73
Causes of purpura in adults
• Immune thrombocytopenic purpura • Bone marrow failure (secondary to leukaemias, myelodysplasia or bone metastases) • Senile purpura • Drugs (quinine, antiepileptics, antithrombotics) • Nutritional deficiencies (vitamins B12, C and folate)
74
Pyoderma gangrenosum
a rare, non-infectious, inflammatory disorder. It is an uncommon cause of very painful skin ulceration. It may affect any part of the skin, but the lower legs are the most common site. Features; usually starts quite suddenly small pustule, red bump or blood-blister the skin then breaks down resulting in an ulcer which is often painful the edge of the ulcer is often described as purple, violaceous and undermined. the ulcer itself may be deep and necrotic may be accompanied by systemic symptoms eg. fever, myalgia
75
Causes of pyoderma gangrenosum
idiopathic in 50% -inflammatory bowel disease in 10-15% -ulcerative colitis -Crohn's rheumatological -rheumatoid arthritis -SLE haematological -myeloproliferative disorders -lymphoma -myeloid leukaemias -monoclonal gammopathy (IgA) -granulomatosis with polyangiitis primary biliary cirrhosis
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Management of pyoderma gangrenosum
Oral steroids and possibly immunosuppressants Surgery when disease is controlled
77
Pyogenic granuloma
most common sites are head/neck, upper trunk and hands. Lesions in the oral mucosa are common in pregnancy initially small red/brown spot rapidly progress within days to weeks forming raised, red/brown lesions which are often spherical in shape the lesions may bleed profusely or ulcerate Management; -lesions associated with pregnancy often resolve spontaneously post-partum -other lesions usually persist. Removal methods include curettage and cauterisation, cryotherapy, excision NB- difference with pyoderma gangrenosum is that they are raised
78
Adverse effects of retinoids
-teratogenicity- females should ideally be using two forms of contraception (e.g. Combined oral contraceptive pill and condoms) -dry skin, eyes and lips/mouth (most common) -low mood/ suicidal ideation -raised triglycerides -hair thinning -nose bleeds (caused by dryness of the nasal mucosa) -intracranial hypertension (not be combined with tetracyclines) -photosensitivity -joint pains
79
Rosacea (acne rosacea)
typically affects nose, cheeks and forehead flushing is often first symptom telangiectasia are common later develops into persistent erythema with papules and pustules rhinophyma ocular involvement: blepharitis sunlight may exacerbate symptoms/ Lifestyle- sun cream applied every day Medical- topical metronidazole, severe disease is treated with systemic antibiotics e.g. Oxytetracycline Specialist- laser therapy (if prominent telangiectasia)
80
Scabies
caused by the mite Sarcoptes scabiei and is spread by prolonged skin contact. Features; widespread pruritus linear burrows on the side of fingers, interdigital webs and flexor aspects of the wrist in infants, the face and scalp may also be affected secondary features are seen due to scratching: excoriation, infection
81
Management of scabies
Lifestyle- avoid close physical contact with others until treatment is complete, all household and close physical contacts should be treated at the same time, even if asymptomatic, iron or tumble dry clothing, bedding, towels, etc., on the first day of treatment to kill off mites. Medical- permethrin 5% is first-line, malathion 0.5% is second-line NB- pruritus persists for up to 4-6 weeks post eradication NB- Ivermectin for crusted scabies
82
Seborrheic dermatitis in adults
a chronic dermatitis caused by an inflammatory reaction to Malassezia furfur (fungus)
82
Seborrheic dermatitis in adults
a chronic dermatitis caused by an inflammatory reaction to Malassezia furfur (fungus) Features; -eczematous lesions on the sebum-rich areas: scalp (may cause dandruff), periorbital, auricular and nasolabial folds -otitis externa and blepharitis may develop Associated conditions; -HIV -Parkinson's disease Management; Scalp- over the counter preparations containing zinc pyrithione ('Head & Shoulders') and tar ('Neutrogena T/Gel'), then ketoconazole Rest of body- topical antifungals: e.g. ketoconazole and topical steroids: best used for short periods
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Shingles
an acute, unilateral, painful blistering rash caused by reactivation of the varicella-zoster virus (VZV). Following primary infection with VZV (chickenpox), the virus lies dormant in the dorsal root or cranial nerve ganglia. Features; prodromal period; burning pain over the affected dermatome for 2-3 days pain may be severe and interfere with sleep around 20% of patients will experience fever, headache, lethargy rash; initially erythematous, macular rash over the affected dermatome quickly becomes vesicular characteristically is well demarcated by the dermatome and does not cross the midline. However, some 'bleeding' into adjacent areas may be seen NB- clinical diagnosis
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Management of shingles
Lifestyle- tell patients they are infected, cover lesions, avoid pregnant women and immunosuppressed (wait until vesicles have crusted over, usually 5-7 days), Medical- analgesia: paracetamol and NSAID's (neuropathic if needed), antivirals within 72 hours of onset (aciclovir)- reduces the chance of post-herpetic neuralgia (can be given after 72 hours of they are at risk ie/ immunosuppressed/elderly) Complications- herpes zoster opthalmicus, herpes zoster oticus (ramsay hunt), post-herpetic neuralgia
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Spider naevi
Causes; Idiopathic liver disease pregnancy combined oral contraceptive pill NB- Spider naevi fill from the centre (spiders sit in the centres of their web), telangiectasia from the edge
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Risk factors for SCC
excessive exposure to sunlight / psoralen UVA therapy actinic keratoses and Bowen's disease immunosuppression e.g. following renal transplant, HIV smoking long-standing leg ulcers (Marjolin's ulcer) genetic conditions e.g. xeroderma pigmentosum, oculocutaneous albinism Management- surgical excision, radiotherapy - for large, non-resectable tumours
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Steven-Johnson syndrome
a severe systemic reaction affecting the skin and mucosa that is almost always caused by a drug reaction. Features; -rash is typically maculopapular with target lesions being characteristic. May develop into vesicles or bullae -mucosal involvement -systemic symptoms: fever, arthralgia Causes; penicillin sulphonamides lamotrigine, carbamazepine, phenytoin allopurinol NSAIDs oral contraceptive pill NB- hospital admission, steroids, immunoglobulins and immunosuppressant medications guided by a specialist.
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Tinea
a term given to dermatophyte fungal infections. Three main types of infection are described depending on what part of the body is infected tinea capitis - scalp tinea corporis - trunk, legs or arms tinea pedis - feet
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Tinea capitis (scalp ringworm)
oral antifungals: terbinafine for Trichophyton tonsurans infections and griseofulvin for Microsporum infections. Topical ketoconazole shampoo should be given for the first two weeks to reduce transmission
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Tinea corporis (ringworm)
causes include Trichophyton rubrum and Trichophyton verrucosum (e.g. From contact with cattle) well-defined annular, erythematous lesions with pustules and papules may be treated with oral fluconazole
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Tinea pedis (athlete's foot)
characterised by itchy, peeling skin between the toes common in adolescence
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Toxic epidermal necrolysis (TEN)
a potentially life-threatening skin disorder that is most commonly seen secondary to a drug reaction. In this condition, the skin develops a scalded appearance over an extensive area. Some authors consider TEN to be the severe end of a spectrum of skin disorders which includes erythema multiforme and Stevens-Johnson syndrome Features -systemically unwell e.g. pyrexia, tachycardic -positive Nikolsky's sign: the epidermis separates with mild lateral pressure Drugs known to induce TEN -phenytoin -sulphonamides -allopurinol -penicillins -carbamazepine -NSAIDs
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Management of TEN
Conservative- stop precipitating factor, admit to hospital Medical- supportive care (ICU), volume loss and electrolyte derangement are potential complications, IV immunoglobulins, immunosuppression
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Urticaria
describes a local or generalised superficial swelling of the skin. The most common cause of urticaria is allergy although non-allergic causes are seen. Features; pale, pink raised skin. Variously described as 'hives', 'wheals', 'nettle rash' pruritic Management; non-sedating antihistamines are first-line (loratadine, cetirizine, sedating would be prochlorperazine eg.) prednisolone is used for severe or resistant episodes
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Chickenpox (primary varicella) vaccine
This is a live attenuated vaccine. Example indications include: -healthcare workers who are not already immune to VZV -contacts of immunocompromised patients (e.g. child whose parent is undergoing chemotherapy)
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Venous ulceration
Investigations; -ankle-brachial pressure index (ABPI) is important in non-healing ulcers to assess for poor arterial flow which could impair healing -a 'normal' ABPI may be regarded as between 0.9 - 1.2. Values below 0.9 indicate arterial disease. Interestingly, values above 1.3 may also indicate arterial disease, in the form of false-negative results secondary to arterial calcification (e.g. In diabetics) Management; -compression bandaging, usually four layer (only treatment shown to be of real benefit)
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Vitiligo
an autoimmune condition which results in the loss of melanocytes and consequent depigmentation of the skin. Features; well-demarcated patches of depigmented skin the peripheries tend to be most affected trauma may precipitate new lesions (Koebner phenomenon) Associated conditions; type 1 diabetes mellitus Addison's disease autoimmune thyroid disorders pernicious anaemia alopecia areata Management; lifestyle- sunblock, camouflage make-up medical- topical corticosteroids, topical tacrolimus and phototherapy (caution needs to be exercised with light-skinned patients)
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Erysipelas vs cellulitis
Erysipelas is distinguished from cellulitis by a well-defined, red raised border
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Erysipelas vs cellulitis
Erysipelas is distinguished from cellulitis by a well-defined, red raised border
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Risks for melanoma
excessive UV exposure, skin type I (always burns, never tans), history of > 100 moles or atypical neavus syndrome moles, family history in first degree relative or previous history of melanoma
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Features of eczema
acute- bitchy papules with exudative vesicles chronic- dry, scaly patches, erythema, lichenification, altered pigmentation NB- most common on face and extensor aspects in new-borns, flexor aspects in adults
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Management of eczema
Conservative- avoid exacerbating agents, emollients, soap substitute Medical- topical steroids, oral antihistamines, ABX if secondary infection NB- phototherapy, immunosuppressants, biologics for severe/non-responsive cases NB- can get secondary bacterial infection, eczema herpeticum, and molluscum contagiosum
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Management of psoriasis
1. Primary care- regular emollients, topical corticosteroid (betamethasone) and vitamin D analogue (Calcipotriol) separate (or (Dovobet- combined)), short acting dithranol 2. Secondary care- phototherapy 3. Systemic therapy- oral methotrexate, biologics eg. infliximab, etanercept NB- complication: erythroderma NB- if corticosteroid doesn't work, then continue vitamin D analogue (can't use steroids long-term) NB- vitamin D analogue (Calcipotriol) is the only one that can be used long-term (wouldn't use steroids long-term) NB- need to know the order of steroid potency eg. eumovate, dermovate etc.
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Hand foot and mouth disease
Hand, foot and mouth disease is caused by the coxsackie A virus (or enterovirus). Incubation is usually 3 – 5 days. viral upper respiratory tract symptoms such as tiredness, sore throat, dry cough and raised temperature small mouth ulcers appear, followed by blistering red spots across the body (most notable on the hands, feet and around the mouth) Painful mouth ulcers rash may be itchy No treatment
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Nappy rash
Contact dermatitis
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Management of nappy rash
Switching to highly absorbent nappies (disposable gel matrix nappies) Change the nappy and clean the skin as soon as possible after wetting or soiling Use water or gentle alcohol free products for cleaning the nappy area Ensure the nappy area is dry before replacing the nappy Maximise time not wearing a nappy Infection with candida or bacteria warrants treatment with an anti-fungal cream (clotrimazole or miconazole) or antibiotic (fusidic acid cream or oral flucloxacillin).
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Causes of non-blanching rashes in children
Meningococcal septicaemia Henoch-Schonlein purpura (HSP) Idiopathic thrombocytopenic purpura (ITP) Acute leukaemias: Haemolytic uraemic syndrome (HUS) Mechanical Traumatic (NAI) Viral illness
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Investigations for non-blanching rash
Full blood count: Urea and electrolytes: C-reactive protein (CRP): Erythrocyte sedimentation rate (ESR): Coagulation screen, including PT, APTT, INR and fibrinogen Blood culture: Meningococcal PCR: Lumbar puncture: Blood pressure: Urine dipstick:
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Staphylococcal scolded skin syndrome (SSSS)
a condition caused by a type of staphylococcus aureus bacteria that produces epidermolytic toxins Features; generalised patches of erythema skin looks thin and wrinkled formation of fluid filled blisters called bullae, which burst and leave very sore, erythematous skin This has a similar appearance to a burn or scald Nikolsky sign fever, irritability, lethargy and dehydration. If untreated it can lead to sepsis and potentially death. Management- IV fluids and ABX
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Difference between bullous pemphigoid (BP) and pemphigus vulgaris (PV)
BP- no mucosal (oral) involvement PV- mucosal (oral) involvement
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Causes of hair loss
Alopecia Tinea capitis Psoriasis Discoid lupus
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Multiple courses of topical steroids
Aim for a 4 week break before considering another course of topical steroids
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Strawberry naevus (capillary haemangiomas)
Not present from birth Develop rapidly in first weeks of life If treatment is required (e.g. Visual field obstruction) then propranolol is increasingly replacing systemic steroids as the treatment of choice. Topical beta-blockers such as timolol are also sometimes used. NB- Cavernous haemangioma is a deep capillary haemangioma Potential complications -mechanical e.g. Obstructing visual fields or airway -bleeding -ulceration -thrombocytopaenia
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Port wine stain
Unlike salmon patches and strawberry naevus they do not spontaneously regress
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salmon Patches
They are pink and blotchy, and commonly found on the forehead, eyelids and nape of the neck. They usually fade over a few months, though marks on the neck may persist.
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Bullous pemphigoid vs pemphigus vulgaris
BP- older, no mucosal involvement, Nikolskys negative, tense and firm blisters PV- younger, mucosal involvement, Nikolskys positive, flaccid/ruptured blisters
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Ototoxicity
Ototoxicity is an important side effect of the aminoglycoside antibiotics, which include gentamicin, neomycin, and tobramycin. Neomycin is the aminoglycoside that is most ototoxic.