Dermatology Flashcards
What disease is erythema nodusm seen in?
Early stages of sarcoidosis
What colour is a lupus pernio rash? and where is it usually seen? What condition is it associated with?
blue/purple and usually seen on skin of nose bridge/beneath eyes and cheeks. Chronic sarcoidosis
What bacteria causes lupus vulgaris?
Myobacterium TB
Which organism is there a hypersensitivity to in seborrheic dermatitis?
Malassezia furfur - a superficial fungal infection
How does seborrheic dermatitis present?
Scaling plaques and underlying erythema
How is seborrheic dermatitis treated?
Topical steroids and anti-fungals
What type of referral does a BCC warrants except if it’s massive or in risk location?
Routine referral
What is a predictor of a bad melanoma prognosis?
Deep lesion
What is pityriasis versicolour? (tinea versicolour)
Flaky discoloured hypopigmented patches mainly on chest and back due to proliferation of Malassezia furfur yeast.
Which condition can cause cafe au lait spots?
Neurofibromatosis type 1
What hormone level in pregnancy is associated with hyperpigment?
High oestriol
What is urticaria pigmentosa?
It is a rare disease caused by excessive numbers of mast cells in the skin that produce hives or lesions on the skin when irritated - usually disappear by teenage years
What is whipple’s disease?
caused by the bacteria Tropheryma whippelii. Symptoms include chronic digestive issues, weight loss, and joint pain. Other symptoms include neurological issues, endocarditis, and infections in the joints, lungs, and eyes
What can whipple’s disease do to the skin?
Cause hyperpigmentation
What can skin burns do to potassium levels?
Increase potassium levels
How should burns be treated?
Calcium gluconate: stabilises myocardium
Insulin and glucose - to reduce the potassium by shifting it into cells
Chromium salts can be found in what occupational object? And what can it result in
Cement - dermatitis
What type of hypersensitivity reaction is SLE and henoch-schonlein purpura?
Type 3
What is a type iv reaction?
Delayed
What is a type i reaction?
Immediate hypersensitivity
What is an early sign of acne rosacea?
Facial flushing
How is mild rosacea treated?
Topical metronidazole twice a day for 6-9 weeks
How is severe rosacea treated?
Oxytetracycline
When does scabies reaction come on?
It’s usually delayed and 4 weeks post exposure when the mites eggs have opened.
How may scabies be detected in GP?
With the felt tip test which can show burrow or delineated lines for example in hand web spaces.
What is 1st line treatment for scabies?
Permethrin
What treatments must be trialled in psoriasis before starting on methotrexate or ciclosporin (must be used for a short course only to induce remission)?
Retinoids, vitamin D, topical corticosteroids and PUVA (photochemotherapy)
If Retinoids, vitamin D, topical corticosteroids and PUVA (photochemotherapy), ciclosporin and methotrexate don’t work what can be used for psoriasis?
Etanercept - biotherapy - it’s an Anti-TNF
What is a seborrheic keratosis?
a non-cancerous skin growth that appears as a wart-like bump on the skin - usually in old ppl
What is a melanocytic naevus
a non-cancerous skin lesion that contains clusters of pigment-producing cells called melanocytes. It’s more flat
Which skin rash is associated with coeliac?
Dermatitis herpetiform - red, itchy blisters.
What skin lesion can appear post viral infection that are harmless?
Viral warts - can use cryotherapy to get them off if there are only a few of them
What is pemphigus vulgaris?
a rare group of autoimmune diseases. It causes blisters on the skin and mucous membranes. can cause the skin to peel off
What is a tzanck test?
The Tzanck smear is mainly used in an acute
setting to rapidly detect a herpes infection or to distinguish Stevens- Johnson syndrome / toxic epidermal necrolysis (SJS/TEN) from staphylococcal scalded skin syndrome. However, it can be used to diagnose a variety cutaneous infections and blistering diseases.
What would a tzanck test show with pemphigus vulgaris?
Acantholytic cheranitoncytes
What does denuded mean?
Removal/ peeling of skin
What would CMV show on a smear?
Multinucleated giant cells
Which drugs are most common in triggering psoriasis flares?
Beta blockers
Antimalarials
Lithium
Interferons
When would you treat hyperkalaemia?
Only if pt is symptomatic or K is equal to or greater than 6.5 mmol or there are ECG changes
What is the pathophysiology of acne?
Propionibacterium acne causes hydrolysis of complex lipids in sebum to FA in turn causing inflammation of the hair follicles.
How is dermatitis herpetiform treated?
With gluten free diet and dapsone (antibiotic)
How to differentiate between psoriasis and seborrheic dermatitis on hair area?
In seborrheic dermatitis the patches are usually confined to hairline and hair loss is uncommon where as in psoriasis they extend beyond the hairline .
What are periungual fibromas? Koenen’s tumor
skin-colored or reddish nodules seen on the lateral nail groove, nail plate, or along the proximal nail folds. They are more commonly found on the toes than on the fingers.
Associated with tuberous sclerosis
What is a keratoacanthoma?
Fast growing, dome shaped skin tumour on a sun exposed area. They rapidly grow like 2cm in a few weeks.
How quickly do keratoacanthoma’s resolve?
With 4-6 months leaving a scar. Complete excision is not needed but is a choice
How does a SCC look?
Ulcerated and may bleed . May look scaley or horn like
How is SCC treated?
Surgical excision
In recurrent cases of BCC or BCC where it’s on ears, nose , face what can be useful?
Moh’s microscopy
What is 1st line treatment for seborrheic dermatitis?
Ketoconazole 2% cream 1-2 x a day for 4 weeks
What is the difference between a STSG (split thickness skin graft) FTSG (full thickness skin graft)
STSG is the entire epidermis and varying thickness of dermis
FTSG is entire epidermis and entire dermis.
STSG can heal by primary intention but FTSG must be sutured and healed by secondary intention.
What is the definition of cellulitis?
Local inflammation in the subcut layer
What is the most common causative bacteria of cellulitis?
Strep pyogenes
How is cellulitis treated?
IV penicillin
Which bacteria cause impetigo?
Staph aureus
How is impetigo treated?
Topical fuscidic acid or oral flucloxacillin
What is the treatment for vitiligo?
Phototherapy , corticosteroids, tacrolimus ointment
What type of drug is tacrolimus?
Immunosuppressant
Which auto-antibodies are present in coeliac?
Anti-endomysial antibodies
What type of antibodies are present in coeliac? and what other cells
IGA depostis, neutrophil infiltration, fibrin deposition which is seen on light microscopy.
What are some complications of hereditary haemorrhagic telangiectasia?
GI , resp complications
Bleeding
Anaemia
Dyspnea
Stroke
Cirrhosis
Which blisters need deroofing?
Thin walled over 6mm
Thick walled on palms, soles and fingertips
Blister with rupture or loose skin
Which autoantibodies cause all types of pemphigus?
Desmoglein
What does tinea corporis look like?
Rig shaped fungal rash with scaly patches and central clearing with distinct borders.
What is Behcet’s disease?
Recurrent painful ulcers in genitals that heal with scarring.
Retinitis and uveitis
Erythema nodousm
Cerebral vasculitis
Headaches, seizures, confusion
Increased IgA
How is Bechet’s disease treated?
Colchicine
Glucocorticoids
Immunosuppressant: cyclophosphamide + Azathioprine
Anti-tnf - infliximab
At what level of hyperkalaemia do tall tented T waves appear?
6 or more mmol
What are osborne waves (J waves) due to?
Hypothermia
How does alopecia areata start then progress?
Coin size patches which then may become confluent to bigger patches
Short tapered hairs may be seen at edge of bald patches
(Exclamation mark hairs)
What is a sign of regrowth in alopecia?
Fine white hair
What is actinic keratosis (solar keratosis)?
Scaly area of skin that feels rough With time they may become hard with a wartlike surface. Also known as a solar keratosis, an actinic keratosis grows slowly and usually first appears in people over 40.
Can sometimes become SCC
What is treatment for actinic keratosis?
5 fluorouracil
Topical diclofenac
Imiquimod cream
Cryotherapy
What’s the most common skin cancer?
BCC
What is the 2nd most common skin cancer?
SCC
What does SCC look like?
Small, red, ulcerated with scaling
What does BCC look like?
Pearly nodules, raised edges and telangiectasia
What is an infantile haemangioma? (STRAWBERRY MARK)
Red raised growth in first 6 months of life anywhere on the body. They then shrink and disappear by 7 years
What is a Port wine stain (capillary malformation)
Non raised red/ purple stain increases in size during pregnancy, puberty and menopause
What is a salmon match (stork mark)
Light pink on forehead, neck eyelids - disappear within a few months
How many cafe au lait spots on a child would warrant a investigation into neurofibromatosis type 1?
6 or more
What is the difference between a carbuncle and furuncle?
SC collections of pus but furuncle is like a boil - there’s only one discharging sinus but in carbuncle there’s two or more discharging sinuses
Which rash is associated with IBD and early sarcoidosis?
Erythema nodosum
Which rash is associated with penicillin, phenytoin use, NSAIDS, sulfar drugs, HSV, Mycoplasma
Erythema multiforme
What’s the differences between NF1 and NF2?
NF1: cafe au lait spots, optic nerve tumours, skeletal dysplasia, learning disabilities
NF2: Balance issues, hearing problems, vestibular schwannoma
What is lichen planus?
a chronic inflammatory disease that affects the skin, nails, hair, and mucous membranes. Shiny purple plaques on skin and white wickham striae on tongue
What does chronic lichen planus put someone at risk of?
SCC
How is lichen planus treated?
Topical steroids
Immunomodulators
What is idiopathic thrombocytopenia purpura?
Number of platelets decrease due to being destroyed. Spreads purpura and bruising and occasional nose bleeds
What is 1st line treatment in idiopathic thrombocytopenia purpura?
Prednisolone and dexamethasone
What is 2nd line for scabies?
Malathion cream
What is Wallace’s rule of 9 ?
Estimates burn size. One palmar surface of hand = 1% of body surface
What is 1st line treatment for psoriasis?
Betnovate and vitamin D (calciptriol)
What is 1st line investigations for NF1?
MRI brain - then look for evidence of bone deformity (skeletal dysplasia)
What is erythema ab igne caused by?
Peoplewho sit near fires for ages of use hot water bottles to much - due to the infrared radiation that comes off these things
What is most common complication of peutz jehgers?
Cancer
What is a distinct way of telling there is a malignant melanoma?
Easy bleeding
What is prescribed first line for mild-moderate acne?
Benzyl-peroxide
What is prescribed for acne if there is scarring risk ?
Benzyl peroxide + topical clindamycin
What is prescribed for moderate acne involving back and shoulders?
Oral clindamycin
Do BCC metastasise?
Rarely and if they do it’s local invasion
What is guttate psoriasis?
Tear drop shapes
Salmon pink colour papules that have a fine scale
Usually on trunk and upper limbs
What can trigger guttate psoriasis?
2/3 of pt will have a recent strep throat infection - the guttate psoriasis will occur after the infection
In scarlet fever a rash occurs, is it before after or during infection?
It’s during infection
“strawberry tongue”
Rash that feels rough like sandpaper
What is erythrodermic psoriasis?
Dermatological emergency a red rash to form over most of your body - looks like a burn.
Drop in BP
Tachycardic
Hypyrexia borderline
Rigors
What is treatment for erythrodermic psoriasis?
Admit to hospital
IV fluids
Wet cool dressings
Ciclosporin IV as it’s fast acting. Methotrexate is more slow acting
What type of pathogen is pityriasis rosacea caused by?
Virus - NOT FUNGUS
What is discoid lupus erythematous?
utoimmune skin condition on the lupus erythematosus spectrum of illnesses. It presents with red, painful, inflamed and coin-shaped patches of skin with a scaly and crusty appearance, most often on the scalp, cheeks, and ears.
Photosensitive rash
What is pyoderma gangrenosum associated with?
IBD
What diagnoses pyoderma gangrenosum?
Painful necrolytic lesion, cutaneous ulcers and a rapid response to systemic steroids Fever
Joint pain
Pustules that may develop into ulcers
Pathergy, an exaggerated response to minor skin injuries
What is treatment for pyoderma gangrenosum?
Systemic corticosteroids, Ciclosporin, and Infliximab
What is another name for 5-fluorauracil cream ? and what does it do?
Efudix - destroys abnormal cells in top layer of the skin
What is Chondrodermatitis nodularis
Benign nodules on ear associated with pressure on ear usually due to sleeping on sides. Treat with steroids: clob
Gold standard therapy is excision
What is lentigo maligna?
Melanoma in situ
Slow growing
Hasn’t yet spread to dermis
Takes years to develop usually in sun exposed areas
What is a dermatofibroma?
Overgrowth of fibrous tissue in dermis due to minor skin in trauma e.g. insect bite - it’s bengign
After how many weeks using a topical steroid for psoriasis in the same spot must a break be had.
after 8 weeks use a 4 week treatment break is needed
Which skin layer is involved in psoriasis?
Epidermis
What is telogen effluvium?
thinning or shedding of hair resulting from the early entry of hair in the telogen phase. It is in this phase that telogen hairs begin to shed at an increased rate,
Triggers: child birth, severe trauma, illness
What is anagen effluvium?
a form of nonscarring alopecia commonly associated with chemotherapy.
Other triggers: anti-depressants, allopurinol, beta blockers, retinoids
Why should infliximab be avoided in pt with latent TB?
Because it can reactivate it instead use adalimumab
What is Kaposi’ sarcoma?
cancer cells are found in the skin or mucous membranes that line the gastrointestinal (GI) tract, from mouth to anus, including the stomach and intestines. These tumors appear as purple patches or nodules
Associated with AID’s defining malignancy caused by HSV 8
What is an AIDS defining malignancy?
If a person with HIV develops one of these cancers, it means they have AIDS.
What is prescribed for headlice?
Dimeticone 4% lotion
How does molluscum contagiousum get treated?
Usually goes away by itself in 1-2 years. Unless infected. If the molluscum is causing anxiety or discomfort potassium hydroxide can be used
What is spa folliculitis?
Red macules that evolve to papules
What bacteria causes spa folliculitis?
Pseudomonas aerguginosa in contaminated waters - can enter hair follicle resulting in pustular eruption
What is a marjolin ulcer?
SCC which develops in a scar (usually in burn scars)
Painless and slow growing as it’s mostly avascular and contains no nerves
Name a vitamin D analogue?
Calciptriol
What is pompholyx? (dyshidrotic eczema)
a skin condition that causes itchy eczema blisters to form on the hands and feet
What pathogen causes hand foot and mouth?
Coxackie virus
What is Nikolsky’s sign?
Skin slough’s off due to toxic epidermal necrolysis - usually due to drug induced reactions
How is fungal infection tested?
Scraping for mycology
What skin rash can occur with TB?
Erythema nodusm
What is definition of erythroderma?
Any condition that causes more than 90% of skin surface to become inflamed, erythematous and scaly
Where does atopic dermatitis usually occur?
In flexures
What is naevus flammus? - another word for port wine stain
Unilateral homogenous red to violet macule due to capillary vascular malformation - can occur anywhere but usually face - follows the trigeminal nerve (5th nerve) distribution can be a marker of underlying neuro or ophthalmological condition
What is dobovet?
Gel containing both calcipotriol (vitamin d analogue) and betamethasone (steroid_
For severe burns which fluid should be given?
Haartman or ringers lactate as it most closely resembles plasma and contains a small amount of lactate which can buffer any metabolic acidosis due to the burnH
What is the formula to work out how much fluid to give burn patient?
Parkland formula: 4ml x weight x total body surface area (burned)
Half of the total fluid volume should be given within the first 8 hours, and the other half within the next 16 hours
What is Necrobiosis lipoidica?
Necrobiosis lipoidica is a rare, chronic skin condition predominantly associated with diabetes mellitus. It can also occur in individuals with rheumatoid arthritis
Shiny well-defined plaques waxy and yellow with overlying telangiectasia
What is 1st line treatment for verucas for HPV?
Salicylic acid
What may be an initial common complaint a patient with acitinic keratosis may come with when starting 5 fluoruracil treatment?
The lesion looks worse for the first 4 weeks
What are dermal melanocytosis (mongolian spot)?
Blue / grey birth mirk
When do mongolian spots dissapear?
By age 4
Which have better reinnervation, sensation and stress tolerance FTSG or STSG?
FTSG + less susceptible to scarring and contractures
What are desmogleins auto antibodies to?
Desmosomes
What is koebner’s phenomenon
In psoriasis - appearance of new skin lesions of a pre-existing dermatosis on areas of cutaneous injury in otherwise healthy skin. can look like scar lines
Difference in what’s attacked in vulgaris vs bullous pemphigoid?
Vulgaris: desmosomes
Bullous: Hemidesmosomes
What is asteatotic eczema?
Asteatotic eczema is a common type of dermatitis that occurs as a result of dry skin and is primarily due to water loss from the stratum corneum.
Present with ‘ crazy paving’ pattern on low limbs
Can be associated with diuretic use and hypothyroid and dry winter climates.
