Derm 4.5

Question 1

Intertriginous & peri-oral dermatitis, alopecia, taste impairment, diarrhoea, short stature, hypogonadism, hepatosplenomegaly, cognitive impairment, glucose intolerance - what deficiency?

Answer 1

Zinc

Question 2

Pellagra, dermatitis, alopecia, oedema, glossitis, weakness, ataxia, paralysis, peripheral neuritis - what deficiency?

Answer 2

Niacin

Question 3

rx of acne rosacea?

Answer 3

• topical metronidazole if mild
• systemic Abx eg Oxytetracycline if more severe
• high sf
• laser Rx if prominent telangiectasia

Question 4

Mild topical steroid?

Answer 4

Hydrocortisone 0.5-2.5%

Question 5

Moderate topical steroid?

Answer 5

Betamethasone 0.025% (Betnovate RD)

Clobetasone butyrate 0.05% (Eumovate)

Question 6

Potent topical steroid?

Answer 6

Fluticasone propionate 0.05% (Cutivate)

Betamethasone valerate 0.1% (Betnovate)

Question 7

V potent top steroid?

Answer 7

Clobetasol propionate 0.05% (Dermovate)

Question 8

Rx for SCC of skin?

Answer 8

• surgical excision with 4mm margins if lesion <20mm in diameter
• if >20mm then margins should be 6mm
• Mohs micrographic surgery in high-risk
• of high risk, then do surgery & consider systemic Retinoids

Good prognosis = well differentiated, <20mm diameter, <2mm deep, no ass diseases

Poor = poorly differentiated, >20mm diameter, >4mm deep, immunosuppression

Question 9

Psoriasis Rx?

Answer 9

• regular emollients
  1st line = potent steroid OD + vit D analogue OD deparately, for 4weeks
  2nd line = vit D analogue BD if no improvement after 8wks
  3rd line = potent steroid BD for 4wks OR coal tar prep OD/BD, if no improvement after 8-12wks
• short acting dithranol can also be used

Question 10

Vitamin D analogues in psoriasis?

Answer 10

• reduce cell division & differentiation
• adverse effects uncommon
• can be used long term
• don’t smell/stain
• reduce scale & thickness of plaques but not erythema
• avoid in pregnancy

Question 11

2ry care Rx for Psoriasis?

Answer 11

Phototherapy

• narrow band UVB Rx of choice 3x/wk
• PUVA photo chemotherapy
• adverse effects: skin raging, SCC

Systemic Rx

• 1st line MTX esp if joint disease
• ciclosporin: palmoplantar, considering conception, rapid/short term disease control
• systemic retinoids
• biologics: infliximab, etanercept, adalimumab
• Ustekinumab IL-12 & IL-23 blocker showing promise in early trials

Question 12

Bullous pemphigoid = autoimmune condition causing sub-epidermal blistering of skin, 2ry to development of Ab against hemidesmosomal proteins BP180 & BP230
Features?
Skin Bx?
Rx?

Answer 12

• more common in elderly
• itchy, TENSE blisters typically around flexures
• blisters HEAL without scarring
• mouth spared classically
• immunofluorescence shows IgG & C3 at dermoepidermal junction
• oral steroids
• top steroids, immunosuppressants & Abx also used
• classic causes are: furosemide, penicillamine, captopril

Question 13

crusty enlarging lumps on a background of acinic keratosis on sun-exposed skin. They may ulcerate and are often tender or painful
Dx?

Answer 13

SCC skin

Question 14

ix for venous ulcers?

Rx?

Answer 14

ABPI to assess poor arterial flow which could impair healing
- normal is 0.9-1.2, if <0.9 arterial disease is suggestive, but can have false negative with arterial calcification

• compression banding, 4layer
• oral Pentoxifylline = peripheral vasodilator, improves healing rate

Question 15

Vitiligo: AI condition which results in loss of melanocytes & depigmentation of skin, Sx develop age 20-30
Features?
Ass conditions?
Rx?

Answer 15

• well-demarcated patches of depigmented skin
• peripheral most affected
• Koebner phenomenon
• T1DM, Addison’s, AI thyroid, pernicious anaemia, alopecia areata
• Rx = sunblock, camouflage make-up, top steroids, may be a role for top tacrolimus & phototherapy

Question 16

Polymrphic eruption of pregnancy

• when
• where
• Rx?

Answer 16

• itchy rash with 3rd trimester
• 1st in abdo striae
• emollients, top steroids, oral if severe

Question 17

Pemphigoid gestationis

• what
• where
• when
• Rx?

Answer 17

• itchy BLISTERING lesions
• peri-umbilical then spread to trunk, back, buttocks, arms
• 2nd/3rd trimester (rarely ever in 1st pregnancy)
• oral steroids usually needed

Question 18

Hereditary haemorrhagic telangiectasia = auto dom telangiectasia on skin & mucous membranes
4 main Dx criteria?

Answer 18

1. epistaxis: spontaneous, recurrent
2. telangiectasia: at characteristic sites
3. visceral lesions: GI, pulm, hepatic, cerebral, spinal AVM
4. FHx: 1st degree relative

Question 19

Pemphigus vulgairs = AI disease caused by Ab against desmoglein 3, a cadherin type epithelial cell adhesion molecule, more common in Ashkenazi jewish
Features?

Answer 19

• mucosal ulceration often PC
• skin blistering - FLACCID early ruptured vesicles & bull, PAINful but not itchy - may develop months after initial mucosal Sx
• acantholysis on Bx

Question 20

Erythema multiform = hypersensitivity reaction most commonly triggered by infections

• features?
• causes?

Answer 20

• target lesions
• initially on back of hands/feet before spreading to torso
• UL more commonly affected than LL
• pruritus occasionally seen & mild
• HSV commonest, Orf
• idiopathic
• mycoplasma, streptococcus
• penicillins, sulfonamides, carbamazepine, allopurinol, NSAIDS, OCP, nevirapine
• SLE
• sarcoid
• malignancy

Question 21

4 main subtypes of melanoma?

Answer 21

superficial spreading 70%

nodular
- red/black lunp or lump which bleeds/oozes

lentigo maligna

acral lentiginous - subungual pigmentation or on palms/feet

Question 22

Ix & Rx of malignant melanoma?

Answer 22

• Incomplete excision Bx of suspicious lesions

0-1mm thick - 1cm
1-2mm - 1-2cm
2-4mm - 2-3cm
>4mm - 3cm

Question 23

Cholestasis-induced pruritus Rx options?

Answer 23

rifampicin
sertraline
cholestyramine

Question 24

Erythema nodosum = inflammation of SC fat - tender, erythematous nodular lesions over shins usually, resolves within 6wks, heal without scarring
Causes?

Answer 24

• streptococci, TB, brucellosis
• sarcoid, IBD, Behcet’s
• malignancy, lymphoma
• penicillins, sulphonamides, COCP
• pregnancy

Question 25

rx of guttate psoriasis? | - precipitated by strep infection 2-4wks prior

Answer 25

- most resolve spontaneously 2-3months - topical agents as per psoriasis - UVB - tonsillectomy may help with recurrent episodes

Question 26

Pyoderma gangrenosum: typically on LL starts as small red papule later deep, red, necrotic with violaceous border +/- systemic Sx - Causes? - Rx?

Answer 26

``` idiopathic 50% IBD RA, SLE myeloproliferative disorders lymphoma, myeloid leukaemias IgA monoclonal gammopathy PBC ``` - oral steroids as potential for rapid progression - other immunosuppressants may have a role

Question 27

What is Palmar-plantar erythrodysesthesia

Answer 27

- common side-effect of many chemo Rx, from days-months into Rx - tingling & numbness in fingers/palms then toes/soles - then erythematous rash which can desquamate, blister & ulcerate which can be ass with onycholysis - Rx depends on severit

Question 28

What is yellow nail syndrome? | associations?

Answer 28

- slowing of nail growth leads to characteristic thickened & discoloured nails - congenital lymphoedema - pleural effusions - bronchiectasis - chronic sinus infections

Question 29

Prognostic markers ass with Severe eczema? Rx of eczema?

Answer 29

``` onset age 3-6months severe disease in childhood ass asthma/hayfever small family size high IgE serum levels ``` - emollients - topical steroids - UV radiation - immunosuppressants eg ciclosporin topical, antihistamines, azathioprine

Question 30

Conditions ass with seborrhoea dermatitis? | Features?

Answer 30

- HIV - PD - eczematous lesions on sebum-rich areas e.g. scalp, periorbital, auricular, nasolabial folds - otitis externa & blepharitis may develop

Question 31

Lichen planus - features? causes of drug eruptions? Rx?

Answer 31

- itchy, papular, polygonal, white-lace pattern - Koebner phenomenon - oral involvement in 50% - thinning of nail plate, longitudinal ridging - Gold, Quinine, Thiazides - topical steroids - benzydamine mouthwash/spray for oral - extensive lichen Plans may need oral steroids/immunosuppression

Question 32

Main side-effect of Dapsone?

Answer 32

Haemolytic anaemia - need reg FBCs | - also peripheral neuropathy, rarely agranulocytosis

Question 33

Erythroderma - 95% skin involved - causes? - what is erythrodermic psoriasis?

Answer 33

- eczema, psoriasis, drugs e.g. gold, lymphoma, leukaemia, idiopathic - progression of chronic disease to exfoliative phase with plaques covering most of body, ass with mild systemic upset - more serious form is acute deterioration that may be triggered by e.g. withdrawal of systemic steroids

Question 34

Pityriasis versicolor = superficial cutaneous fungal infection caused by Malassezia fur fur - features? - predisposing factors? - Rx?

Answer 34

- commonly trunk, hypo pigmented/pink/brown patches more noticeable after a suntan, scale common, mild pruritus - yellow-green fluorescence under Woods lamp - in healthy, immunosuppression, malnutrition, Cushing's - Rx = topical antifungal - consider other Dx or oral itraconazole if fails to respond

Question 35

rx for face/flexural/geinital psoriasis?

Answer 35

Mild/moderate potency steroid OD/BD for max 2 wks

Question 36

Steven-Johnson syndrome = severe systemic reaction affecting skin & mucosa almost always a drug reaction - when does it occur? - features? - causes? - Rx?

Answer 36

- 1-4weeks after 1st drug exposure, on average day 14 - maculopapular rash with target lesions, may develop vesicles/bullae - mucosal involvement - fever, arthralgia - penicillin, sulfonamide, lamotrigine, carbamazepine, phenytoin, allpurinol, Nsaids, OCP - hospital admission for supportive Rx

Question 37

Pellagra = nicotinic acid/niacin deficiency | - features?

Answer 37

- can be a consequence of isoniazid Rx, more common in alcoholics - dermatitis bron scaly rash on sun-exposed sites - diarrhoea - dementia, depression

Question 38

Bowen's disease = intraepidermal SCC more common in elderly females - 3% chance of developing invasive skin cancer - features? - Rx options?

Answer 38

- red, scaly patches, often occur on sun-exposed areas e.g. LL - Top 5-FU or IMIQUIMOD - cryotherapy - excision

Question 39

Rx of actinic keratoses?

Answer 39

- SPF, avoid sun etc - Fluorouracil cream 2-3wks (topical steroid can help inflammation that it will case) - topical diclofenac - topical Imiquimod - cryotherapy, curettage & cautery

Question 40

Exacerbating factors of psoriasis?

Answer 40

``` trauma ETOH withdrawal of systemic steroids beta-blockers lithium antimalarials NSAIDs ACE-I infliximab ```

Question 41

Polymorphic light eruption = 1ry photosensitivity commonly occurs in young women - when/what

Answer 41

- usually each spring provoked by several hours outside on a sunny day - rash settles if further exposure avoided

Question 42

lesions due to Microsporum canis green fluorescence under Wood's lamp*. However the most useful investigation is scalp scrapings Dx?

Answer 42

Tinea capitis (scalp ringworm) - causes scarring alopecia - Rx oral Terbinafine for Trichophyton tonsurans infections; Griseofulvin for Microsporum infections - give topical Ketoconazole shampoo for the first 2 weeks to reduce transmission

Question 43

causes include Trichophyton rubrum and Trichophyton verrucosum (e.g. From contact with cattle) well-defined annular, erythematous lesions with pustules and papules Dx? Rx?

Answer 43

``` Tinea corporis (ringworm) - oral fluconazole ```