Dermatology Flashcards
what is vitiligo associated with
autoimmune hypothyroidism
pernicious anaemia
alopecia areata
addisons
Type 1/ 2 polyendocrine syndromes
endocrine causes of itch
hypo/hyperthyroid
DM
diabetes insipidus
drugs that cause itch?
opiates
gold
alcohol
hepatotoxics
OCP
drugs commonly causing urticaria?
aspirin
penicillin
NSAIDs
opiates
endocrine causes of hyperpigmentation?
Addison’s disease
Cushing’s syndrome
Acromegaly
Nelson’s syndrome
pregnancy
metabolic causes of hyperpigmentation?
Types of alopecia?
scarring - destruction of hair follicle
non-scarring - preservation of hair follicle
causes of scarring alopecia?
trauma, burns
radiotherapy
lichen planus
discoid lupus
tinea capitis*
causes of non scarring alopecia?
male pattern baldness
drugs: cytotoxics, carbimazole, OCP, heparin, colchicine
iron/ zinc deficiency
alopecia areata (Autoimmune)
telogen effluvium (15% -> 70& of scalp hairs in resting state, secondary to shock)
management of alopecia areata?
usually nothing - spontaneous recovery
can consider
in limited patchy hair loss:
- intralesional corticosteroid
in extensive patchy hair loss:
- contact immunotherapy
GI causes of clubbing?
ulcerative colitis/ crohns
liver cirrhosis
primary biliary cirrhosis
Causes of onycholysis?
idiopathic
trauma
infection: fungal
psoriasis/ dermatitis
impaired peripheral circulation e.g. Raynauds
Systemic disease: hyper/ hypothyroidism
Causes of erythema multiforme?
viruses: herpes simplex, orf
idiopathic
bacteria: mycoplasma, strep
drugs: penicillin, sulphonamides, OCP, carbamazepine
SLE
Sarcoid
malignancy
Ix for venous ulceration?
ABPI
- impt to assess for poor arterial flow which could impair healing
- <0.9 indicates arterial disease
- >1.3 may also indicate arterial disease secondary to arterial calcification e.g. diabetics
management of venous ulcers?
four layer compression bandaging
- oral pentoxifylline (peripheral vasodilator) may improve healing rate
- small evidence base supporting flavinoids
what drugs may exacerbate psoriasis?
beta blockers
lithium
antimalarials (chloroquine and hydroxychloroquine)
NSAIDs and ACE inhibitors
infliximab
Management of tinea capitis?
oral griseofulvin for 2 - 3 months
or ketoconazole for resistant cases
management of pityriasis versicolor?
topical antifungal e.g. terbinafine/ selenium sulphide
if extensive/ failure to respond to topical treatment then consider oral itraconazole
what diameter is suggestive of melanoma?
>6mm
what is the single most important factor determining prognosis of patients with malignant melanoma?
Breslow depth
<1mm: 95-100% 5- yr survival
1-2mm: 80-96%
2.1-4: 60-75
>4mm: 50%
Causes of Nikolsky’s sign?
pemphigus vulgaris
porphyria cutanea tarda
drug reactions esp pseudoporphyria
Management of genital warts if multiple, non-keratinised?
topical podophyllum
management of solitary ketanised genital wart?
cryotherapy
associated conditions with seborrheic dermatitis?
otitis externa
blepharitis
*seborrhoeic dermatitis is more common in pts with Parkinson’s disease/ HIV
what organism is implicated in seborrheoic dermatitis?
Malasezzia furfur
management of scalp seborrheoic dermatitis?
OTC preparations containing zinc pyrithione (head and shoulders) and Tar (Neutrogena T/ Gel)
2nd line: ketoconazole
management of face/ body seborrheoic dermatitis?
topical antifungal e.g. ketoconazole
topical steroids for short periods
difficult to treat- recurrences are common
what may erythema ab igne predispose to?
if cause is not treated, may develop Squamous skin cancer
- caused by overexposure to infrared radiotherapy
how to diagnose leprosy?
skin biopsy: showing mycobacterium leprae
what toxin is Staph aureus most likely to be producing in recurrent Staph aureus skin infections?
Panton-Valentine Leukocidin (PVL) producing S aureus
management of peristomal pyoderma gangrenosum?
tacrolimus
antibodies that you might see in paraneoplastic pemphigus?
anti-envoplakin/ periplakin / desmoplakin
anti bullous pemphigoid antigen I/ alpha2- macroglobulin like 1
anti- desmoglein 3/1
Sezary syndrome?
assoc w Cutaneous T cell lymphoma
Lipodermatosclerosis affects which structure of the skin?
hypodermis