Dermatology Teaching Flashcards
What is teledermatology?
also known as skin analytics
professional clinical photography of skin lesions that can be sent digitally to a dermatologist for triage
helpful when seeing patients in clinic to review these images for comparison
Which benign lesion presents similarly to melanoma?
atypical naevus (funny looking mole)
Which premalignant lesions present similarly to SCC?
How would you explain these to patients who ask - “ so is this cancer? “
Actinic keratosis
Bowen’s disease
Sun damage to top layer of skin = actinic keratosis
Sun damage that goes slightly deeper = Bowens disease
Sun damage that affects the full thickness of the skin = squamous cell carcinoma - ulceration suggests carcinoma as it affects the full thickness
Which is more concerning - darker pigment at the centre of a mole, or darker pigment at the periphery?
Darker pigment at the periphery - suggests it is spreading
What are Longitudinal melanonychia?
dark stripes on the nails - patients with darker skin should check in their nail beds for these as they can be a precursor to melanoma
What is Hutchinson’s sign?
Suggestive of melanoma
periungual extension of brown-black pigmentation from longitudinal melanonychia onto the proximal and lateral nailfolds
Kaposi sarcoma often presents with visible lesions on the mucosa. How else may it present ?
with unilateral limb swelling
Which are the high risk areas of skin post-transplant for patients with darker skin?
patients with darker skin are more at risk in their sun protected sites post transplant- palms of hands and soles of feet and genital area - they should keep an eye on these areas for any changes
Which types of skin lesions are transplant patients with fair skin more susceptible to?
Which type of lesions are transplant patients with darker skin more susceptible to?
patients with lighter skin are more at risk of SCC
patients with darker skin are more at risk of Kaposi sarcoma
Which are the high risk areas of skin post-transplant for patients with lighter skin?
sun exposed areas - backs of hands, forearms, face, ears
What blood tests may you want to do for a patient with hair loss?
check thyroid, ferritin (aim for 70 and above) and vitamin D
What are these lesions?
solar lentigos - sun spots
What is this lesion?
an intradermal naevus
Do you expect new moles to develop in the older population?
no - any new moles over the age of 40 is concerning
Which immunosuppressant drug is a particular driver of skin cancer?
Azathioprine
How can you roughly estimate the percentage of body surface affected by a rash / a burn?
palm rule : the size of their palm = 1% of their body surface area
rule of 9s: arm = 9%, chest = 9%, stomach = 9%
What type of hypersensitivity reaction is SJS?
Type 4 hypersensitivity reaction – unlike anaphylaxis, symptoms gradually come on as offending drug builds up in the body
What should you ask all patients with suspected SJS?
Always ask about palms, soles and mucous membranes – involvement of these is the distinguishing feature
Always ask about OTC meds as well as prescribed
Ask about recent infection
What systemic sxs may be seen in SJS?
Pyrexia
Sore throat
Flu like sxs
Sore red eyes, conjunctivitis
Arthralgia
What is the difference between SJS and TENS?
SJS = 10% body involvement
TENS is the same as SJS but with over 30% body involvement
How might you investigate SJS?
Skin biopsy
Culture – swab culture or blood culture
Blood tests for inflammatory markers
CXR for lung involvement
What can be used to predict mortality in SJS?
SCORTEN score can be used to predict mortality in SJS and TENS cases:
Age >40
Presence of malignancy
HR >120
Initial epidermal detachment >10%
How can you manage SJS?
Stop offending meds
IV Fluids
Wound care, Eye care
Analgesics, topical steroids, abx
IV Immunoglobulins (within 72 hours)
What is pyoderma gangrenosum? How would you describe the lesions?
Autoimmune neutrophilic dermatosis
Usually on the legs because it is a common site of trauma
Well demarcated, erythematous, ulcerative nodule on a background of normal skin
How could you investigate pyoderma gangrenosum?
Pathergy test positive – skin prick test causes a papule, pustule or ulcer
Wound swab
Skin biopsy
ANCA blood test
How can you manage pyoderma gangrenosum?
Potent topical steroid – e.g. dermovate
Can also do intralesional steroid injections
Can give doxycycline because it is a very good anti-neutrophil drug
Can give oral prednisolone if severe
Skin changes around a stoma =
think Pyoderma gangrenosum!
