Dermatology Flashcards
What are features of rosacea?
Photosensitive rash on cheeks/nose
Papules/pustules
Telangiectasia
Rhinophymia
What is mild rosacea and how is it managed?
Erythema/flushing only - no pustules or papules
Mangement - topical brimonidine and lifestyle changes
What is moderate rosacea and how is it managed?
Mild papules and pustules
Topical metronidazole
Topical azelaic acid
What is severe rosacea and how is it managed?
Extensive papule and pustules
Oral abx e.g. oral oxytetracycline
How are telangiectasia in rosacea managed?
laser therapy
What are medications which exacerbate psoriasis?
BLANQET Beta blockers Lithium Anti-malarials NSAIDs Quinolones E T
How is eczema herpeticum treated?
Needs admission for IV Aciclovir
Which infections are associated with erythema multiforme?
HSV
Mycoplasma pneumoniae
Which rash presents with a herald patch and then a fir tree rash?
Pityriasis rosea
Which rash presents with a tear drop rash?
Guttate psoriasis
How is actinic keratosis treated?
5-fluorouracil cream
topical imiquimod
sun avoidance/suncream
What margins are needed for excisional biopsy for SCC?
Less than 20mm = 4mm margins
More than 20mm = 6mm margins
Major criteria for melanoma?
Change in size
Change in shape
Change in colour
Minor criteria for melanoma?
Diameter > 7mm
Inflammation
Oozing/bleeding
Altered sensation
What is lichen planus (what signs do you see) and how is it managed?
Skin disorder
Purple, pruritic, papular, polygonal
Koebner phenomenon - new lesions at site of trauma
Wickham’s striae - white line pattern
Management = topical corticosteroids
What drugs can cause SJS/TEN?
Never Press Skin As It Can Peel (Nikolsy’s Sign)
NSAIDs Phenytoin Sulphonamides Allopurinol/Anti-epileptics - Lamotrigine/Carbamazepine/Phenyton IV Ig COCP Penicillins
SJS vs TEN?
SJS = Maculopapular rash + target lesions with systemic features e.g. fever, arthralgia
TEN = Very high fever, widespread tender erythema and widespread mucosal involvement
Leads to full thickness necrosis
TEN = Nikolsy’s sign (skin peels with pressure)
What is Bowen’s disease? How does it present and how is it managed?
Precancerous lesion which can become SCC
Red scaly patches in sun exposed areas
5-fluorouracil cream
Which type of melanoma can affect areas not exposed to the sun?
Acral lentiginous melanoma
Which rash is associated with coeliac disease and how is it managed?
Dermatitis herpetiformis
Dapsone
How to tell the difference between the different types of burns?
Superficial –> blanching erythema
Superficial dermal –> blisters
Deep dermal –> white; and patches of non-blanching erythema
Full thickness –> painless
What skin cancer is most common in patients with a renal transplant?
Squamous cell carcinoma
What are 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
What is a keratocanthoma?
Benign epithelial tumour
Slow growing but can look similar to a SCC
Urgent excision needed due to difficulty excluding SCC
What medications can cause erythema nodosum?
Penicillins
Sulphonamides
COCP
In which conditions is the Koebner phenomenon seen in?
- psoriasis
- vitiligo
- warts
- lichen planus
- lichen sclerosus
- molluscum contagiosum
What are causes of spider naevi?
Liver disease
Pregnancy
COCP
Rosacea vs. malar rash in SLE?
SLE – spares nose
Spider naevi vs. telangiectasia?
Spider naevi fill from the centre
Telangiectasia fill from the edge
What is Athlete’s foot and how does it present? How is it managed?
Tina infection (tinea pedis) Scaling/flaking/itchy between toes
Topical ketoconazole
How is a fungal nail infection treated?
If singular nail can use Amorolfine nail lacquer
Otherwise - oral terbinafine
Which melanoma is most common?
Superficial spreading
Which melanoma is most aggressive and most likely to bleed/ooze?
Nodular
What are risk factors for squamous cell carcinoma?
Actinic keratosis
Bowen’s disease
Immunosuppressed
Smoking
When should you admit someone with cellulitis?
If they are: Under 1 year Frail Significant systemic upset - tachycardia/tachypnoea/hypotension Sepsis Necrotising fasciitis Immunocompromised Facial cellulitis
How is severe cellulitis treated?
Co-amox
What is pyoderma gangreosum? What is it associated with? How is it. managed?
Rapidly enlarging painful ulcer IND RA SLE Myeloproliferative disorders
management = oral steroids
How is erythema nodosum treated?
Self-limiting
Can give NSAIDs
What are non dermatological causes of pruritus?
Liver disease Iron deficiency anaemia Chronic kidney disease Polycythaemia Lymphoma
What is the stepwise management of psoriasis in primary care?
1) topical potent corticosteroid + vitamin D analogue (both once daily)
2) vitamin D analogue twice a day
3) topical potent corticosteroid twice a day or coal tar preparation twice a day
