Dermatology Flashcards
ACNE
What is it and when is the normal onset?
Inflammation of pilosebaceous units
adolescence to early adulthood
ACNE
Features of Acne?
1) Increased sebum production by sebaceous glands
2) Colonisation of pilosebaceous glands by Propionibacterium acnes
3) Follicular epidermal hyperproliferation + blockage of pilosebaceous ducts
ACNE
Why is it more common during puberty?
- Androgen and progesterone production increases so sebum production increases
ACNE
Types of Acne?
- Open comedones- blackheads- keratin
- Closed comedones- Whiteheads- sebum, keratin and deeper in ducts
ACNE
What may closed comedones cause?
Inflammatory papules , nodules &cysts
ACNE
First Line treatment?
Keratolytics (benzyl peroxide)- thins skin, clears pores, decreases bacteria
Topical Retinoids- (iso/tretinoin), topical erythromycin
ACNE
Second Line treatment?
low does Abx ( Doxycycline/ erythromycin)
ACNE
Third line treatment?
- Po retinoids (isotretinoin )
vitamin A analogues that affect cell growth and differentiation
ECZEMA
Aetiology?
- Abnormal epithelial barrier function
- Allows antigens/irritants to penetrate skin & reach immune cells
ECZEMA
Which cell(s) drive the acute phase?
Th-2 CD4 Lymphocytes
ECZEMA Which cell(s) drive the chronic phase?
Th0/Th1 CD4 lymphocytes
ECZEMA
Exacerbating factors?
- animal hair
- strong detergents
- dietary allergens
ECZEMA
Where is it normally found and what does it look like?
- usually found in flexures
- Itchy, erythematous, scaly patches
ECZEMA
Management?
1) Emollient creams (hydrate)
2) Steroid creams e.g hydrocortisone/ betamethasone
CONTACT DERMATITIS
Cause?
- CLeaning products
- Chemical irritants
- Type IV hypersensitivity
CONTACT DERMATITIS
Features?
- Unusual rash, clear cut borders/ odd shaped areas of erythema/ scaling
CONTACT DERMATITIS
Treat?
1) Remove cause
2) Steroids
3) Antipruritic agents `
PSORIASIS
Cause and triggers?
- polygenic- 9 loci identified
1) Group A strep infection
2) UV light
3) Lithium
4) Alcohol
5) Stress
All T- lymphocyte driven
PSORIASIS
What is plaque psoriasis?
found in kids/ adults
- Eruption of small circular plaques, on trunk, 2 weeks after strep infection (sore throat)
PSORIASIS
What is Erythrodermic psoriasis?
severe and life threatening
- widespread intense inflammation of the skin- fever, malaise, circulating problems
PSORIASIS
What may be seen if someone has psoriasis?
1) pitting/ onycholysis / yellow- brown nails
2) Psoriatic arthritis in 20% of patients
PSORIASIS
Management? (1st and 2nd)
1st - emollient creams (hydrate)
2nd- Topical Agents - Vit D3 analogues (calcipotriol)
- Coal tar
- Retinoids (Tazorotene)
- Corticosteroids
- Salicylic acid
PSORIASIS
3rd and 4th line treatment?
3rd- UV radiation - risk of skin cancer/ ageing
4th- Systematic therapy if all else fails and also erythrodermic psoriasis requires systematic therapy
- Oral retinoids
- Immunosuppression (methotrexate, azathioprine)
- Biological Agents (infliximab)
SKIN CANCER
What is the most serious case of skin cancer?
MALIGNANT MELANOMA
Metastases early and hard to treat after this
SKIN CANCER
Criteria of malignant melanoma?
Asymmetry of mole Border irregularity Colour variation Diameter >6mm Evolution
SKIN CANCER
List the Glasgow 7 point Criteria
MAJOR
- Change in size
shape
colour
MINOR
- diameter >6mm
- inflammation/bleeding
- mild itch/ altered sensation
SKIN CANCER
Name 4 types of melanoma?
Superficial Spreading Melanoma
Nodular Melanoma
Lentigo Malignant Melanoma
Acral Lentiginous Melanoma
SKIN CANCER
What is Superficial Spreading Melanoma (70% of melanomas)
Large, flat, irregular pigmented lesion that grows out before deep
SKIN CANCER
What is Nodular Melanoma? (15% of all melanomas)
- rapidly growing pigmented nodule that bleeds/ ulcerates
SKIN CANCER
What is Lentigo Malignant Melanoma?
- Patch of ‘lentigo melanoma’- slow growing lesion on face of elderly
SKIN CANCER
WHat is Acral Lentiginous Melanoma?
Pigmented lesions on palm, sole or under nail
SKIN CANCER
Treat?
- excision
- mets treated with chemo
What is Basal Cell Carcinoma?
- most common malignant skin tumour
- occurs later in life on sun exposed skin
- shiny nodule which may ulcerate
Treatment of basal cell carcinoma and squamous cell carcinoma?
- excision
- radiotherapy to treat mets/ recurrence
What is Squamous Cell Carcinoma?
- more dangerous than BCC as it can metastasise
- ulcerated lesion with hard, raised edges at sun exposed sites
SKIN ULCERS
What are they?
Abnormal breaks in epithelial surface
SKIN ULCERS
Different classes?
- Venous (70%)
- Mixed A+V (15% )
- Arterial (2%)
- neuropathic, diabetic, traumatic, infective, lymphoedema
SKIN ULCERS
Where is a common site for a venous skin ulcer and how does it occur?
1) Incompetence of valves in lower legs
2) Blood pooling and varicose veins
3) They aren’t drained fast enough- dies and sloughed off leaving ulcer, commonly just above medial malleolus
SKIN ULCERS
Cause of Arterial Skin Ulcer?
- Atheroma
- More painful and shallow
- NEVER use compression bandaging
SKIN ULCERS
Management?
1) prevent smoking, adequate nutrition, good nursing care
2) Compression bandaging if ABPI okay
don’t cut off blood supply! this is a cause
CELLULITIS
What is it
- spreading infection involving deep subcutaneous layer
CELLULITIS
Causes
Group A strep / s pyogens/ s aureus
CELLULITIS
Lower limb risks?
- lymphoedema
- ulcer
- trauma
- athletes foot
CELLULITIS
Features
- Erythema, poorly marked margins, warmth, swell, tender, maybe a fever
CELLULITIS
Ix?
- FBC
- Cultures
- swab at rash/ point of entry
CELLULITIS
Treatment?
- Phenoxymethylpenicillin/ Flucloxacillin (erythromycin if allergic)
NECROTIZING FASCIITIS
What is it?
Rapid deep fascia infection = necrosis of subcutaneous tissue
NECROTIZING FASCIITIS
Features?
- pain
- erythema
- systemic toxicity
NECROTIZING FASCIITIS
Treat?
-benzylpenicillin and surgical debridement
