Dermatology Flashcards
What is TEN?
Toxic epidermal necrolysis
Scalded appearance to skin
Systemically unwell/febrile
Nikolsky’s sign the epidermis separates with mild lateral pressure
What drugs can cause TEN?
phenytoin
sulphonamides
allopurinol
penicillins
carbamazepine
NSAIDs
Features + treatment of Pityriasis (tinea) Versicolor
cutaneous fungal infection caused by Malassezia furfur
trunkal patches of hypopigmentation, pink or brown, scale, mild puritus
may become more obvious with a suntan
manage with keotoconazole shampoo
Psoriasis Management
1- potent corticosteroid OD + vitamin D analogue applied OD for 4 weeks
2 - increase vitamin D analogue to BD
3- increase potent corticosteroid to BD for 4 weeks or coal tar preparation OD or BD
4- referral for systemic or phototherapy
Scalp psoriasis management
1- potent topical corticosteroids OD for 4 weeks
2- trial different formulation of corticosteroid + topical agent to remove scale e.g. salicylic acid.
Face, flexural and genital psoriasis management
mild or moderate potency corticosteroid applied once or twice daily for a maximum of 2 weeks
Causes of Stephen Johnson Syndrome
penicillin
sulphonamides (co-trimoxazole)
lamotrigine, carbamazepine, phenytoin
allopurinol
NSAIDs
oral contraceptive pill
Three Pregnancy Specific Skin Changes?
1: Atopic eruption of pregnancy - looks like eczema
2: Polymorphic eruption of pregnancy - pruritic, last trimester, lesions often appear in abdominal striae first,
emollients, steroids.
3: Pemphigoid gestationis - pruritic blistering lesions, peri-umbilical region, spreading to the trunk, back, buttocks and arms 2nd or 3rd trimester and is rarely seen in the first pregnancy.oral corticosteroids are usually required.
Causes of acanthosis nigricans
type 2 diabetes mellitus
gastrointestinal cancer
obesity
polycystic ovarian syndrome
acromegaly
Cushing’s disease
hypothyroidism
familial
Prader-Willi syndrome
drugs: COCP, nicotinic acid
Pityriasis versicolor appearance, caused by , management
Hypopigmented or brown patches , often on torso
Malassezia furfur
kzetokonozole shampoo –> skin scrapings and itraconazole PO
What virus causes Molluscum?
MCV - poxvirus
What virus causes hand foot and mouth disease?
Coxsackievirus
What virus causes slapped cheek syndrome?
Parvovirus B19
Dermatitis artefacta vs. Neurotic excoriations?
DA - patient denies they are self induced
NE - patient will admit they are self inflicted
Steroid cream potency
Help Every Budding Dermatologist
Mild - Hydrocortisone
Moderate - Eumovate
Potent - Betnovate
Very Potent - Dermovate
What are dermatofibromas? (AKA Histiocytoma)
Solid nodules/papules caysedby abnormal growth of histiocyte cells. ‘dimple sign’. often occur at site of insect bite/thorn prick/
Pyogenic granuloma
misnomer - benign lesions usually affecting young people
pyoderma gangrenosum
neutrophilic dermatosis - painful necrotic ulcers of the lower limbs.
associated with IBD, requires immunosuppression e.g. infliximab
fungal nail infections
-causes
-management
dermatophytes 90%
candida 10%
<2 nails - amorolfine lacquer
oral terbinafine or itraconazol for candida
What is Pityriasis rosea?
Self limiting rash of young adults
‘heald patch’ usually on trunk followed erythematous scaly patches which may sit along line pf langer
Acne rosacea management
flushing only - brimonidine gel
mild to moderate - ivermectin topical (or topical metronidazole or azelaic acid)
moderate to severe - topical ivermectin + oral doxycycline
Rhinophyma/ treatment failure- refer
Superficial Spreading Melanoma: Frequency, typically affects, appearance
70%
arms/legs/torso - young people
a growing mole in locations above
Nodular melanoma
Frequency, typically affects, appearance
2nd most common melanoma
sun exposed skin, middle aged
red or black lump +/- bleeding/ooze
Lentigo maligna melanoma
Frequency, typically affects, appearance
less common
chronically sun exposed skin - older people
a growing moles with diagnostic features
Acral lentiginous melanoma
rare
nails, palms, soles. People with darker skin pigmentation
sublingual pigmentation on palms or feet
