Urticaria Flashcards
Name the term that means “increased thickness of keratin layer”
Hyperkeratosis
Name the term that means “increased turnover of keratinocytes/persistence of keratin nuclei”
Parakeratosis
Name the term that means “increased thickness of epithelium”
Acanthosis
Define “papillomatosis” and name a condition it is present in
Irregular epithelial thickening
Acanthosis nigricans
Define “spongiosis”
Oedema between keratinocytes
In psoriasis, what is the basic pathology that is occuring?
Parakeratosis in the corneal layer
What is meant by the Koebner phenomenon?
Trauma to a site of the body can stimulate skin lesions in that particular area
Neutrophils are present in the corneal layer in psoriasis. True/False?
True
Unusual but true
What is Auspitz sign in psoriasis?
Bleeding spots when psoriasis scales are scraped off
Where does acne vulgaris tend to affect?
Sites of high sebaceous gland concn
face, neck, upper back, chest
How does sebum, produced by sebaceous glands, lead to acne?
Sebum builds up in the hair follicle, increasing pressure to cause rupture
What are comedones?
Keratin and sebum build up in hair follicles, producing whiteheads and blackheads
Rosacea is commoner in males. True/False?
False
Commoner in females
What are the facial features of rosacea?
Erythema with no comedones Flushing Visible blood vessels Pustules Thickened skin (rhinophyma)- enlarged unshapely nose
List some triggers of rosacea
Alcohol
Sunlight
Spicy food
Stress
Which mites are often present in rosacea?
Demodex mites
Name 3 examples of immunobullous diseases
Pemphigus
Bullous pemphigoid
Dermatitis herpetiformis
What is the most common subtype of pemphigus?
Pemphigus vulgaris
Pemphigus vulgaris is an autoimmune condition. What happens?
IgG antibodies made in response to desmoglein 3 - this is the glue that maintains desmosomal attachments
intra-epidermal (thin roofed)
In bullous pemphigoid, where does the blistering develop?
Underneath the epidermis
Acantholysis (loss of desmosomal attachments in epidermis) occurs in bullous pemphigoid. True/False?
False (occurs in pemphius vulgaris)
pemphigus is intra-epidermal
Bullous pemphigoid is an autoimmune condition. What happens?
IgG produces antibodies against hemidesmosomes
Causes epidermis to separate from basement membrane (at the DEJ)
is subepidermal
Dermatitis herpetiformis is linked to which GI disease?
Coeliac disease
How is dermatitis herpetiformis produced in coeliac patients?
IgA against wheat cross-reacts against connective tissue matrix proteins
What is the commonest form of psoriasis?
Chronic plaque psoriasis (psoriasis vulgaris)
Psoriasis is symmetrical and usually affects flexor surfaces. True/False?
False
Symmetrical and affect extensor surfaces
List treatment for psoriasis
Emollients Vitamin D analogue Coal tar Steroid ointment Phototherapy Systemic therapy- methotrexate (immunosuppression)
Give examples of vitamin D analogues
Calcipotrol (Dovonex)
Calcitrol (Silkis)
What is the basic function of retinoids in psoriasis?
Reduces skin turnover (reduces parakeratosis)
Which organism can colonise the hair follicle duct, causing acnes?
Propionibacterium acnes
Open comedones are called blackheads/whiteheads
Closed comedones are called blackheads/whiteheads
Open comedones are called blackheads, closed comedones are called whiteheads
List topical treatment for acne
Keratolytic – Benzoyl peroxide
Retinoids (vit A derivative) - Tretinoin= drying effect
Antibiotics – Tetracycline= antibacterial and anti-inflammatory
What does benzoyl peroxide do?
Keratolytic + antibacterial
What type of drug is adapalene?
Topical retinoid (dries skin)
Name an oral retinoid that can be used for systemic treatment of acne
Isotretinoin
Comedones are present in rosacea. True/False?
False
Outline treatment for rosacea
Reduce triggers
Topical antibiotic- metronidazole
Oral antibiotic- tetracycline
Low dose isotretinoin if severe
Bullous pemphigoid is a deep blister; pemphigus is a superficial blister. True/False?
True
BP goes through DEJ; pemphigus is intra-epidermal between keratinocytes
What is Nikolsky sign?
Top layers of the skin slip away from the lower layers when slightly rubbed; i.e., popped blister
Which disease - bullous pemphigoid or pemphigus vulgaris - is Nikolsky positive?
Pemphigus vulgaris
Outline treatment for pemphigus and pemphigoid
Steroid
Immunosuppressive
Tetracyline in pemphigus
What is psoriasis?
Chronic inflammatory skin condition defined as itchy red skin with scaly silver-white papules and plaques.
What is psoriasis linked with?
Arthritis
Nails- onycholysis
What is guttate psoriasis?
“Teardrop” psoriasis seen in young adults
o Occurs two weeks after strep throat infection
o Resolves spontaneously but recurrence is likely
What are lichenoid disorders?
Conditions characterised by damage to basal epidermis and infiltraton between the epidermis and dermis
What is lichen planus?
T-cell mediated inflammation
Rash is characterised by small, purple flat-topped, polygonal papules that are very itchy.
Where is lichen planus more common?
More common on flexors of wrists and legs
Oral lesions are very common
White reticular network in mouth (‘Wickham’s striae’)- lace-like pattern on surface of papules and buccal mucosa
What is the management for lichen planus?
Underlying cause (drug reaction)
Emollients +/- Steroids +/- Phototherapy
What is the pathogenesis of acne vulgaris?
poral occlusion, bacterial colonisation of duct, dermal inflammation, sebum production
What glands do acne come from?
Pilosebaceous glands
