Dermatology Flashcards
What is eczema ?
A chronic atopic condition caused by defects in the normal continuity of the skin barrier leading to inflammation in the skin.
How does eczema present ?
Dry, red, itchy and sore patches of skin over the flexor surfaces.
What is the pathophysiology of eczema ?
Eczema is caused by defects in the barrier that the skin provides. Tiny gaps in the skin barrier provide an entrance for irritants, microbes and allergens that create an immune response resulting in inflammation.
What is the management of eczema ?
Maintenance - emollients and specially designed soap substitutes.
Flares - thicker emollients, topical steroids and wet wraps
What are some thin cream emollients ?
E45
Diprobase cream
Oilatum cream
Aveeno
What are some thick cream emollients ?
50:50 ointment
Hydromol
Diprobase
What is the steroid ladder for eczema ?
Mild - hydrocortisone
Moderate - eumovate
Potent - betnovate
Very potent - dermovate
What is eczema herpeticum ?
A viral skin infection caused by the herpes simplex virus or varicella zoster virus.
HSV-1 is the most common causative organism.
How does eczema herpeticum present ?
Widespread, painful, vesicular rash with systemic symptoms such as fever, lethargy, irritability and reduced oral intake.
Lymphadenopathy
What is the management of eczema herpeticum ?
Aciclovir
What are some investigations for eczema herpeticum ?
Viral swabs
What are some complications of eczema herpeticum ?
Immunocompromised
Bacterial superinfection
What is psoriasis ?
A chronic autoimmune condition that causes recurrent symptoms of psoriatic skin lesions.
Genetic component
What is plaque psoriasis ?
Thickened erythematous plaques with silver scales, commonly seen on extensor surfaces and scalp.
What is guttate psoriasis ?
Small raised papules across the trunk and limbs.
Mildly erythematous and slightly scaly.
What is pustular psoriasis ?
Pustules form under areas of erythematous skin. The pus in these areas is not infectious.
Should be treated as a medically emergency
How does psoriasis present ?
Dry flaky scaly
Slightly erythematous skin lesions
Extensor surfaces and scalp
What is the management of psoriasis ?
Topical steroids
Topical vitamin D analogue ( calcipotriol )
Topical dithranol
Phototherapy
What is nail psoriasis ?
Nail changes that can occur in patients with psoriasis.
Nail pitting, thickening, discolouration, ridging and onycholysis.
What are some associations of psoriasis ?
Nail psoriasis
Psoriatic arthritis
Psychosocial implications
What is acne vulgaris ?
An extremely common skin condition often affecting people during puberty and adolescence.
What is the pathophysiology of acne vulgaris ?
Chronic inflammation with or without localised infection, in pockets within the skin known as pilosebaceous unit.
Acne can result from increased production of sebum, trapping of keratin and blockage of the pilosebaceous unit.
How does acne vulgaris present ?
Red, inflamed and sore spots on the skin.
Macules, papules, pustules, comedomes
Blackheads
What is a macule ?
Flat marks on the skin
What is a papule ?
Small lumps on the skin
What is a pustule ?
Small lumps containing yellow pus
What is a comedone ?
Skin coloured papules representing blocked pilosebaceous units
What is a blackhead ?
Open comedones with black pigmentation in the centre
What is the management of acne vulgaris ?
Topical benzoyl peroxide
Topical retinoids
Topical antibiotics
Oral antibiotics
What is isotretinoin ?
A retinoid that works by reducing production of sebum, reducing inflammation and reducing bacterial growth.
Strongly teratogenic
What are some side effects of isotretinoin ?
Dry skin and lips
Photosensitivity of skin to sunlight
Depression, anxiety, aggression and suicidal ideation
Rarely stevens-Johnson syndrome or toxic epidermal necrolysis
What is viral exanthemas ?
An eruptive widespread rash caused by a viral origin.
What are the 6 diseases that cause exanthem ?
First disease - measles
Second disease - scarlet fever
Third disease - rubella
Fourth disease - duke’s disease
Fifth disease - parvovirus B19
Sixth disease - roseola infantum
How does measles spread ?
Highly contagious via respiratory droplets
How does measles present ?
Fever
Coryzal symptoms
Conjunctivitis
Koplik spots
Rash on the face - erythematous and macular
What are some complications of measles ?
Pneumonia
Diarrhoea
Dehydration
Encephalitis
Meningitis
Hearing loss
Vision loss
Death
What is scarlet fever ?
Associated with group A streptococcus infection - tonsillitis
How does scarlet fever present ?
Red-pink, blotchy macular rash with rough sandpiper skin
Fever
Lethargy
Flushed face
Sort throat
Strawberry tongue
What is the treatment of scarlet fever ?
Abx - penicillin V for 10 days
What are some conditions associated with scarlet fever ?
Post -streptococcal Glomerulonephritis
Acute rheumatic fever
How does rubella spread ?
Highly contagious and spread by respiratory droplets
How does rubella present ?
Erythematous macular rash - starts on face and spreads
Mild fever
Joint pain
Sore throat
Enlarged lymph nodes
What is the management of rubella ?
Supportive
The condition is self limiting
What are some complications of rubella ?
Thrombocytopenia
Encephalitis
Congenital rubella syndrome - in pregnancy
What is the triad of symptoms of congenital rubella syndrome ?
Deafness
Blindness
Congenital heart disease
How does parvovirus B19 present ?
Mild fever
Coryza
Muscle aches
Lethargy
‘Slapped cheeks’
What is the management of parvovirus B19 ?
Self limiting
Supportive - fluids and simple analgesia
What are some complications of parvovirus B19 ?
Aplastic anaemia
Encephalitis or meningitis
Pregnancy complications - foetal death
Rarely hepatitis, myocarditis and nephritis
What is erythema multiforme ?
An erythematous rash caused by a hypersensitivity reaction.
How does erythema multiforme present ?
Produces widespread, itchy, erythematous rash
Target lesions - red rings within larger red rings
Stomatitis
What are some other symptoms present in erythema multiforme other than the rash ?
Mild fever
Stomatitis
Muscle ache
Joint ache
Headache
General flu-like symptoms
How is erythema multiforme present ?
Supportive
Penicillin V
What are some investigations of erythema multiforme ?
CXR to look for mycoplasma pneumonia