learning outcomes Flashcards
layers of the skin
stratum corneum stratum lucidum stratum granulosum stratum spinosum stratum basale
stratum corneum description
hard protein envelope with keratin and lipids
stratum lucidum description
dead cells with dispersed keratohyalin
stratum granulosum description
keratohyalin with a hard protein envelope
stratum spinosum description
keratin fibers and lamellar bodies
stratum basale description
site of cellular mitosis
functions of skin
functions of skin; thermoregulation, immunity via innate and adaptive and a barrier against external damage and retains water, electrolytes and macromolecules. It enables sensation, vitamin D synthesis and interpersonal communication
causes of external skin disease
temperature, UV, chemical, infection or trauma. Internally It may arise form systemic disease, genetics, drugs and infection.
eruptive xanthoma cause
hyperlipidemia
ancanthosis nigricans causes
obesity, malignancy and diabetes
pretibial myxoedema causes
thyroid skin disease
macule term
small circumscribed area
patch term
large circumscribed area
papule term
small raised area
plaque term
large raised area
vesicle term
small fluid filled
bulla term
large fluid filled
pustule term
small pus filled
abscess term
large pus filled
erosion term
loss of epidermis
ulcer term
loss of epidermis and dermis
bacterial investigations in dermatology
if bacterial infection that charcoal swab, microscopy, culture and testing sensitivities.
viral investigations
if viral infection then swab for PCR
fungal skin investigations
if fungal then skin scrapping, nail clipping, hair sample for fungal cultures
if the mechanical barrier of skin fails
sepsis
if fluid or electrolyte balance fails
protein, fluid loss, renal impairment and peripheral vasodilation
what drugs can be topically applied in dermatology
corticosteroids, antibiotics, antiviral, dithranol, vitamin analogues, chemotherapy, parasiticidals, coal tar, anti-inflammatory, salicylic acid.
topical steroids pharamacology
regulate pro inflammatory cytokines, supress fibroblasts, endothelial, leukocytes function. They also stimulate vasoconstriction and inhibit vascular permeability, very safe is used appropriately.
dose of topical steroids
0.5g finger tip
side effects of topical steroids
thinning, atrophy, striae, bruising, hirsutism, telangiectasia, acne, glaucoma, systemic absorption, cataracts
retinoids pharmacology
vitamin A analogues that are anti-inflammatory and anti-cancer for normalising keratinocyte function.
retinoids uses
Used in Acne, psoriasis, T cell lymphoma, and hand eczema.
immunosuppressant examples
steroids, ciclosporin, methotrexate, azathioprine
biologics pharmacology
treating inflammatory conditions. They are genetically engineered proteins derived from human genes for specific components of the immune system.
SJS features
– fever, malaise, arthralgia, rash, mouth ulceration (white membrane, haemorrhagic crusting)
toxic epidermal necrolysis features
prodromal febrile illness, ulceration of mucous membranes, rash, positive nikolsky’s sign.
management for SJS and toxic epidermal necrolysis
stop drug culprit and supportive therapy
pemphigus features
flaccid easily ruptured blisters, commonly around face, groin and axillae. Nikolsky’s sign positive, affects mucous membranes, erosion. Patients may be unwell is extensive.
pemphigus treatment
; systemic steroids, dress erosions and supportive therapy
pemphigoid features
intact blisters usually tense. May be extensive but patient fairly well.
pemphigoid features
intact blisters usually tense, may be extensive but patient fairly well
pemphigoid treatment
topical steroids, only systemic if diffuse.
erythrodermic psoriasis and pustular psoriasis features
withdrawal of topical steroids, rapid development of generalised erythema, clusters of pustules, fever.
erythrodermic psoriasis and pustule psoriasis treatment
avoid steroids, initiate systemic therapy
eczema herpeticum features
punched out erosions and monomorphic blisters, fever, lethargy
eczema herpeticum treatment
aciclovir, treat secondary infection. Mild topical steroid to treat eczema.
staphylococcal scalded skin syndrome features
common in children, diffuse erythematous rash with tenderness, prominent in flexures, develops into blistering and desquamation, fever and irritability.
treatment of staphylococcal scalded skin syndrome
requires IV antibiotics, and supportive care initially.
urticaria features
variable size with erythema with itching and burning sensation. Duration several hours. Acute if less than 6 weeks. Described as a weal, wheal or hive.
acute urticaria treatment
oral antihistamine, short course of oral steroids avoid opiates and NSAIDS
chronic urticaria treatment
standard dose antihistamine, then increase dose. Second line agent anti-leukotriene, tranexamic acid for angioedema. Finally use of omalizumab or cyclosporine.
DRESS first line therapy
systemic steroids
pemphigus first line
systemic steroids
pemphigoid 1st line
topical steroids
eczema herpeticum 1st line
aciclovir
staphylococcal scalded skin syndrome first line
IV antibiotics
urticaria first line
anti-histamines
presentation of psoriasis
sharply demarcated erythematous plaques with micaceous scales with family history. There will be numerous small, widely disseminated papule and plaques with erythroderma and pustules. The nails there will be onycholysis, pitting and oil spots.
signs of psoriasis
Signs include koebner phenomenon and woronoff’s ring. Possible symptoms also include arthritis
pathogenesis of psoriasis
there is multiple genes involved in its development. It then requires something to trigger it in the form of an infection, drug, injury or even sunlight.
There is activation of immune cells in the skin in response to damage. This is then presented to more immune cells which then attacks the stressed skin cells resulting in further skin cell production. White blood cell involvement results in pus formation.
1st line treatment for psoriasis
emollients and soap substitutes with use of vitamin D3 analogues, coal tar creams, careful use of topical steroids and salicylic acid
systemic treatment for psoriasis
Systemic include retinoid, immunosuppression via methotrexate (treats PsArthritis), ciclosporin and biologic therapies.
erythrodermic psoriasis requires what treatment?
requires admission, regulation of fluid balance, bloods and IV access and thick greasy ointment emollients.
carcinoid syndrome signs
episodic flushing, no sweating, facial telangiectasia
paraneoplastic pemphigus signs
erosive stomatitis and rash
erythema gyratum repens signs
concentric erythematous lesions, variable sites that can be affected
acquired hypertrichosis lanuginose signs
acute onset lanugo hairs at face and body
leser trelat signs
eruptive seborrheic keratoses
bazex syndrome signs
– hyperkeratosis of extremities, resembles psoriasis
ectopic ACTH syndrome signs
generalised hyperpigmentation
paget’s and extra mammary paget’s skin sign’s
eczematous plaque at nipple, and primary intraepithelial adenocarcinoma.
skin conditions associated with an underlying cancer?
carcinoid syndrome paraneoplastic pemphigus erythema gryatum repens acquired hypertrichosis leser trelat Bazex Syndrome ectopic ACTH syndrome extra-mammary Paget's disease
acanthosis nigricans signs
older patient, rapid onset, involves lips, weight loss.
dermatomyositis signs
inflammatory myopathy + rash, periorbital heliotrope rash, gottrons papules over bony prominences, shawl sign, photosensitive poikiloderma, scalp erythema
strongly associated with cancer skin condition
acanthosis nigricans
dermatomyositis
associated with malignancy skin conditions
bullous pemphigoid
pyoderma gangrenosum
sweet’s syndrome
genetic cancer syndromes with skin manifestations
MEN
xeroderma pigmentosa
autoimmune GI skin signs
malignant atrophic papulosis (GI haemorrhage), erythema nodosum, pyoderma gangrenosum (IBD)
genetic GI signs
hereditary haemorrhagic telangiectasia, ehlers danlos, pseudo xanthoma elasticum, blue rubber bleb naevus
diabetic skin signs
ancanthosis nigricans, acral erythema, carotenemia, diabetic bullae, diabetic dermopathy, disseminated granuloma annulare, eruptive xanthomas, necrobiosis lipoidica, rubeosis, scleredema
skin conditions associated with autoimmunity
cutaneous lupus
cutaneous vasculitis
alopecia
vitiligo
impetigo features
common in children, arises from poor hygiene and skin trauma. Initially a macule that develops into a vesicle, then pustule with erosion developing with a yellow crust (honeycomb
impetigo management
treatment is local wound care and topical antibiotics if necessary, e.g. around eye but normally self-limiting.
folliculitis features
infection of hair follicle from occlusion, maceration, hydration, waxing, topical corticosteroids and diabetes. Initially a pustule that develops into a cyst or abscess.
folliculitis managment
antibacterial wash and ointments but may require a charcoal swab for identification of bacteria.
erysipelas features
very young, aged and debilitated with lymphoedema or chronic cutaneous ulcers. Erythema with defined margins. Skin feels hot tense and indurated affecting face or lower extremities. Patient may experience fever, chills, malaise and nausea. Progresses rapidly.
erysipelas management
laboratory test highlights elevated leukocyte test, requires 10-14 days penicillin.
cellulitis features
lymphedema, alcoholism, diabetes, IV drug use and peripheral vascular disease. Erythema, warmth, pain and swelling. Ill defined, non-palpable borders. Children affects head and neck, adults affects extremities
cellulitis management
little to test for, requires antibiotics
syphilis features
widespread rash and flu like symptoms separated by periods in time. STI that produces initially a painless ulcer (chancre). Secondary in rash with rough, red/brown papules and patches trunk, palms and soles, no itch. Tertiary is a gumma, granulomatous lesion.
syphilis management
serology test 5-6 weeks after infection, non-specific treponemal tests VDRL, specific anti-treponemal antibody tests TTPA. Treatment is injection of penicillin.
herpes features
; orolabial (1) or genital (2). Sore areas with erythematous base with vesicles followed by pustules and ulcerations.
herpes management
topic antiviral therapy
chicken pox features
contagious virus that causes acute fever, blistering rash in children. Presence of macules that form vesicles, then pustules then crusts. “dew drops on a rose petal”. Starts of scalp and face before spreading to trunk and extremities.
chicken pox management
symptomatics and calamine lotion
shingles features
; localised, blistering and painful rash following a reactivation of varicella zoster virus. Dermatomal distribution. Complications include infection and post-herpetic neuralgia (pain persistence)
shingle’s managment
infection prevention, pain relief and rest.
viral warts features
hyperkeratotic papules, thick plaques, may form mosaic clusters.
viral warts management
salicylic acid or cryotherapy.
molluscum contagiosum features
affects infants <10, overcrowding, warm climates. Firm umbilicated perly papules with waxy surface in skinfolds. molluscum contagiosum management
molluscum contagiosum treatment
curettage, liquid nitrogen, chemovesicants may be self-limiting.
dermatophytosis features
post pubertal affects groin, scalp, foot and nail. Wave lake with centre clear. Results in dead scaly skin with loss of hair.
dermatophytosis management
skin scrape for identifications
candida features
Predisposing factors are diabetes, occlusion, hyperhidrosis, broad spectrum antibiotics, or immunosuppression. Erythematous patches with satellite pustules in creases and folds particularly moist areas like diapers.
candida management
remove predisposing factors, oral antifungal or topical antifungal.
pityriasis versicolour features
sebum rich areas of skin, high temperatures, humid, oily skin, excessive sweating, round oval patches with mild scale. Different colours of brown, white or red.
pityriasis management
topical antimycotic treatment shampoo and creams
scabies features
close contact, overcrowding, passionate itching, presence of burrows, water increases itching, spares the scalp with papules, disturbs sleep, irregular tracks between fingers, palms, wrists and fingers.
scabies management
skin scraping, visualisation and antiscabietic topical treatment.
head lice features
itch and irritation on scalp, behind nape of neck and skin behind ears, red brown spots on skin. Younger children
head lice management
easily visible. 2 applications of insecticide or physical methods inform school or day care.
clinical features of classical dermatitis
flexures, necks, eyelids, face, hands and feet. Acute changes of pruritus, erythema, scale, papules, vesicles, exudate, crusting and excoriation. Chronically there is lichenification (hard leather skin), plaques and fissures.
exogenous eczema features
contact dermatitis, lichen simplex (scratching), photoallergic.
seborrheic eczema features
chronic dermatitis due to malassezia yeast causing red, sharp marginated lesion with greasy scales.
pompholyx eczema features
palms and soles, very itchy, resolution can cause desquamation.
asteatotic eczema features
very dry skin, cracked scales affecting the elderly due to the loss of oil.
venous eczema features
increased venous pressure generating oedema
eczema herpeticum features
disseminated viral infection generating itchy clusters of blisters and erosions
filaggrin gene involvement in atopic dermatitis
the filaggrin gene. Without this gene there is the loss of the protective lipid layers and anti-microbial peptides resulting in a dysfunctional microbial flora causing dry skin. This aids in a barrier dysfunction which results in the escape of water generates inflammation
atopic dermatitis immune response to losing filaggrin gene
the response of T2 cells and subsequent interleukins result in more inflammation and barrier dysfunction generating an antagonistic cycle.
histology findings for atopic dermatitis
there is spongiosis (swelling within the epidermis), acanthosis (thickening of the epidermis) inflammation in the form of superficial perivascular lymphatic infiltrate.
features for diagnosis of atopic dermatitis
itchy skin, plus 3 of the following onsent before the age of 2, history of flexural involvement, history of generally dry skin, atopic disease.
contact dermatitis investigation
patch testing applies Monday, remove Wednesday and re-assess Friday
seborrheic eczema topical treatment
ketoconazole topical anti-yeast
venous eczema treatment
compression stocking
eczema herperticum treatment
admission, antivirals, treat secondary bacterial infection
general treatment for atopic dermatitis
emollients (greasy, light, watery), soap substitutes, intermittent topical steroids. Sometimes may need rotation of topical steroids with calcineurin inhibitors. Anti-histamines and anti-microbials.
treatment for severe eczema
– ultraviolet light or immunosuppression via methotrexate, ciclosporin, azathioprine
acneiform pathophysiology
keratocytes normally undergo their cell cycle and are shed around the hair follicle via the infundibulum. The sebaceous lobule also secretes oily liquid to lubricate the hair follicle. The issue arises when the keratocytes are genetically altered resulting in increased adhesions and shedding resulting in a blockage of the infundibulum. This prevents the secretion of sebum (oil). The normal flora present Propionibacterium acnes then proliferate, resulting in an inflammatory reaction. If this penetrates to the dermis It can cause scarring.
white head cause
white heads if the infundibulum is sealed completely
black head cause
if there is open entry it forms blackheads as the lipid contents oxidise or become infected and form a pustule
epidemiology of acneiform eruptions
90% of teenagers have acne, there are genetic syndrome that increase risk and by 40 1% of men and 5% of women are still symptomatic
presentations for acneiform eruptions
; open and closed comedones, inflammatory lesions, presence of papules, pustules, nodules and cysts in more moderate disease. If severe disease there are the presence of pseudocysts, pigmentation changes and scarring.
acne fulminans features
rare severe cystic acne that is systemic and abrupt.
drug induced acne features
pustules without comedones following use of lithium, phenytoin or steroids
acne excoriee features
picked acne that form crusted scabs that may scar
acne vulgaris features
younger, open and closed comedones, inflammatory lesions, papules, pseudocysts, pustules, nodules and cysts, permanent scarring and post inflammatory pigmentation, seborrhoea.
Rosacea features
common in fair skinned individuals, third and fourth decades, vascular changes, episodic flushing, no sweating, erythema with burning sensation by minor irritants, centrally, papules and pustules in advanced cases with tissue thickening, fibrosis, oedema and glandular hyperplasia. Deep red colour, exaggerated pores and lumpy surface. Another symptom may be eye dryness, tired eyes, tearing, pain, chalazia and corneal damage.
Acne first line
first line is often the use of the anti-inflammatory and anti-septic Benzyl peroxide or topical retinoids (deactivate keratinocyte proliferation)
other treatments for acne
There is also azelaic acid. First line orally is the antibiotics tetracyclin or lymecycline. Older women with menstruation problems may use a contraceptive pill. Final line may be the use of isotretinoin tablets (anti-keratinocyte proliferation and reduces sebum but lots of side effects and teratogenic as well as a long treatment (1yr
rosacea avoid the use of
vasodilators and irritants
rosacea 1st line treatment
1st line is metronidazole cream or gel as a topic therapy
rosacea other treatments
Alternatives are azelaic acid, ivermectin cream(kills mites), tetracyclines are the most oral medications or surgery for rinophymas
pyogenic granuloma features
rapid raw growth at site of trauma. Common on hand or head.
pyogenic granuloma management
curettage or cautery.
angioma management
excision or laser
angioma epidemiology
overgrowth of blood vessels, all ages and sexes but due commonly due to pregnancy or liver disease
lipoma features
smooth, rubbery subcutaneous mass, tender, asymptomatic
dermatofibroma features
fibrous nodule on limbs, firm and tethered to skin but mobile over fat. Pale pink/brown with positive dimple sign. Usually asymptomatic.
dermatofibroma management
excision if symptomatic
cysts features
encapsulated lesion containing fluid or semi fluid, firm and fluctuant
cysts management
excision, if inflamed then antibiotics, intralesional steroids, drainage
viral warts features
rough hyperkeratotic surface
viral warts management
cryotherapy, curette
seborrheic keratoses features
warty growths, variable, multiple +/- cherry angiomas
soberrheic management
cryotherapy or curettage
actinic keratoses features
; low risk precursor to SCC, rough scaly patches on sun damaged skin.
bowen’s disease features
SSC in situ; full thickness dysplasia, contained in epidermis, irregular scaly erythematous plaque.
basal carcinoma features
pearly rolled edge, telangiectasia, central ulceration, arborizing vessels on dermoscopy. Slow growing, locally invasive
squamous cell carcinoma features
sun exposure, metastatic, fast growing, tender, scaly and can ulcerate
SSC variant keratoacanthoma features
hair follicle from damage skin may rapidly grow and shrink.
melanoma features
changing size, shape colour, with inflammation, >5mm diameter, oozing and itching black spot resembling a mole it may be superficial, lentigo, nodular, subungal (under nail), acral lentiginous, or ocular.
mycosis fungoides features
(cutaneous lymphoma); older male patients, flat red oval patches that itch or may resolve, thick itchy plaques, irregular lumpy ulcerating tumour and metastatic.
sezary syndrome features
(cutaneous lymphoma) red man syndrome, skin thick, scaly and red, very itchy with lymph node involvement.
basal cell carcinoma treatment
excision, curettage in some circumstances. If not suitable for surgery or RT (i.e. metastatic) then Vismodegib.
SSC treatment
excision +/- radiotherapy
SSC variant keratoacanthoma treatment
excision
melanoma treatment
surgical excision, lymph node biopsy, may require chemo/immunotherapy. i.e. ipilimumab(CTLA4), pembrolizumab (PD1), vemurafenib, dabrafenib (B-RAF).
mycosis fungoides and sezary syndrome treatment
topical steroids, local radiotherapy, interferon, low dose methotrexate, chemotherapy, bexarotene and total skin electron beam therapy, extracorporeal photophoresis, bone marrow transplant.
what regional cancer regularly metastasize to the skin
breast lung and colon
skin cancers that metastasize
mycosis fungoides, melanoma, squamous cells carcinoma, basal cell rarely.
lymphoma pathophysiology
lymphoma commonly is T cell mediated. It is the result of abnormal neoplastic proliferation of lymphocytes in skin.
