Dermatology Flashcards
Penicillins, Carbamazapine, Lamotrigine and Phenytoin are all known causes of Stevens-Johnson syndrome, name 4 more.
Sulphonamides
Oral contraceptive pill
Allopurinol
NSAIDs
What type of infection precipitates guttate psoriasis?
Streptococcal infection (usually 2-4 weeks prior appearance of the lesions).
What are the features of guttate psoriasis?
Tear drop papules on the trunk and limbs
Tends to be acute onset over days.
What is the management of guttate psoriasis?
Most cases resolve spontaneously in 2-3 months
Topical agents (the same for psoriasis)
UVB phototherapy
Tonsillectomy may be indicated if there is recurrent episodes.
What are the features of pityriasis versicolor?
Most commonly affects the trunk
Patches may be hypopigmented, pink or brown.
Scale is common
Mild pruritis
What are the predisposing factors for pityriasis versicolor?
Healthy individuals
Immunosuppression
Malnutrition
Cushing’s
What is the management of pityriasis versicolor?
Topical antifungal - ketoconazole shampoo
If failure to respond - consider alternative diagnoses (send scrapings) + oral itraconazole.
What is the most aggressive subtype of melanoma? Why?
Nodular
Invades aggressivley and metastasises quickly.
Pregnancy and malignancy are two of the causes of erythema nodusum, name 3 more.
Infection: streptococci and TB
Systemic disease: sarcoidosis, IBD and Behcet’s
Drugs: Penicillins, sulphonamides and COCP
What are the features of a pityriasis rosea rash?
Herald patch (normally on the trunk)
Followed by erythematous, oval, scaly patches.
The rash runs with the lines of Langer.
May be preceded by URTI.
What usually precedes pityriasis rosea?
Viral infection
How long does it ususally take for the rash in pityriasis rosea to resolve?
6-12 weeks
What is the firstline treatment for lichen sclerosus?
Potent topical steroids
Patient presents with skin discolouration on her legs, a reddish-blue net-like pattern of discolouration (non-blanching) that is associated with cold weather. What is the most likely diganosis? What condition is this associated with?
Livedo reticularis
SLE
What rash can be associated with herpes simplex virus?
Erythema Multiforme
What is the typical clinical description of the rash seen in erythema multiforme?
Early lesions are papular and then become target lesions. Erythematous. Usually found on extensor surfaces.
What is the firstline treatment for pyoderma gangrenosum?
Oral prednisolone
What is the managment for a symptomatic chronic subdural haemorrhage?
Burr hole evacuation
Which malignancy is most commonly associated with ancanthosis nigricans?
Gastrointestinal malignancy
What is the school exclusion advice with molluscum contagiosum?
The child can go to school but they should avoid sharing clothes, towels etc due to infectious nature.
Describe the typical rash that presents with shingles.
Maculopapular erytheamatous rash with vesicles and crusting. Dermatomal distribution. Associated with ‘stabbing’ pain.
Beta blockers and lithium are two drugs that are known to exacerbate psoriasis, name 4 more.
NSAIDs
Anti-malarials
ACEi
Infliximab
What is the firstline treatment for hyperhydrosis?
Aluminum chloride (topical)
What is the firsline treatment for lichen planus?
Potent topical steroids
