DUMS Flashcards
Where are melanocytes derived from?
Neural crest
What are the three layers of Keratin (corneocytes)?
Granular
Prickle
Basal
What are the two types of sweat gland and what are their function?
Apocrine = armpit + groin (androgen dependent) Eccrine = normal (everywhere else)
What do melanocytes do?
Convert tyrosine to melanin (for light absorption)
What are the mechanoreceptors in the skin?
Merkel cells
What in the skin senses pressure and vibration?
Pressure = Pacinian corpuscules Vibration = Meissners corpuscules
What type of light is needed for VitD to stimulate Ca absorption from the bowel and mineralisation of bone?
UVB (290-320nm)
What is a porphyria?
Inherited genetic condition that causes accumulation of porphyrins in the body (necessary for RBC function) Either acute (nervous system) or cutaneous (skin)
What are the symptoms of porphyria cutanea tarda?
Burning pain on sun exposure
Blistering on exposed surfaces
Red or brown pee
What is Ramsay Hunt syndrome?
Reactivation of Herpes zoster virus (chickenpox/shingles)
Affects facial nerve (facial palsy)
Vesicles and pain in auditory canal and throat (deafness, vertigo, tinnitus)
What is used to treat herpes?
Aciclovir
What type of herpes causes oral lesions?
HSV type 1
What is erythema multiforme?
Target lesions, usually a drug reaction
How does molluscs contagiosum present?
Raised pink lesions with a dimple, usually in children, self-limiting
What strains of HPV (human papilloma virus) cause genital warts or cervical cancer?
Genital warts: HPV type 6 and 11
Cervical cancer: HPV types 16 and 18
What is erythema infectiosum?
Slapped cheek disease (in kids)
From human parvovirus infection
Rash on face followed by lacy macular rash on body
How does syphillis present and what is the infecting organism?
T. palladium (sexually transmitted)
Genital, mouth or skin ulcer (small and painless open sore)
What are the phases of synphillis infection?
- Primary infection: small painless ulcer at site of entry (mouth/genital)
- Secondary phase: red rash all over body, snail track ulcers on mucous membranes
- Tertiary phase: CNS, CVS involvement
What contagious skin condition is associated with care homes and how is it treated?
Scabies
Malathion lotion
What drug is used to treat staph aureus infection?
Flucloxacillin
What drug is used to treat tinea infections?
Clotrimazole
What are the 2 types of necrotising fasciitis?
Type I: mixed anaerobes/coliforms (post abdominal surgery)
Type II: group A strep infection (strep pyogenes)
What is the order of treatment of psoriasis?
Emollients, VitD analogues (calcitriol) Phototherapy Systemic therapy (methotrexate) Biologics (...numab)
(not steroids due to rebound flares)
What are black and whiteheads called?
Blackhead: open comedone
Whitehead: closed comedone
What is the order of treatment of acne?
Benzoyl peroxide (antibacterial)
Retinoid (adapalene - drying effect)
Isotretin (may cause an initial flare up)
What is the treatment of rosacea?
Topical metronidazole
Long term: oral tetracycline
(avoid steroids)
How do vesicles/bullae appear in pemphigus vs pemphigoid?
Pemphigus vulgaris: flaccid, thin roofed (Superficial)
Bullous pemphigoid: large, tense (deep)
What is Nikolsys signs and what type of bullous disease expresses it? What occurs in the other?
Slight rubbing of the skin causes shedding of the outer layer = Pemphigus
Pemphigoid = erosions (from bursting of blisters)
What disease is an ash leaf macule diagnostic of?
Tuberous sclerosis
What is tuberous sclerosis and how may it present?
Genetic mutation causing non-cancerous tumours across many organ systems
Presents with facial angiofibromas or infantile seizures
What disease presents with cafe au lait spots? What are the more severe manifestations of this disease?
Neurofibromatosis type 1
Learning difficulties, blindness, skeletal disfigurement, may progress to malignancies
How does neurofibromatosis type 2 present?
Bilateral vestibular schwannomas
How does a BCC present?
Slow growing lump or non-healing ulcer
How does an SCC present?
Crusted lump or ulcer on sun damaged skin
Fast growing and may be painful/bleed
What are the precursor lesions to SCC?
Actinic keratoses
Bowen’s disease (red/brown plaques on lower legs of elderly males)
What scale is used to measure the severity of a melanoma? What is the risk <1mm, >4mm?
Breslow thickness
<1mm = 95-100% survival
>4mm = 50% survival
(mets = 5% survival)
What are the growth phases of a melanoma?
Radial growth phase: less invasive
Vertical growth phase: very invasive (risk of mets)
What are the different strengths of topical steroid and give an example of each?
Mild: Hydrocortisone
Moderate: clobestasone butyrate
Potent: betamethasone valerate
Very potent: clobetasol propionate
How does erythema nodosum commonly present?
Red tender lumps or nodules on both shins, usually young people (12-20)
Often have flu-like symptoms and aching joints first
Self-resolving within 30 days
How does pyoderma gangrenosum commonly present and who gets it?
Deep ulcers usually on the legs that become necrotic (after initial small red papule)
Seen with IBD (UC/crohns) and connective tissue disorders
What disease is associated with a non-blanching rash?
Henoch-Schönlein purpura
