Common Dermatological Conditions Flashcards
What questions do you focus on in a dermatological history?
Childhood complaints Family history Other medical history; eg: hay fever What else have you tried? What makes it worse? When did it start? What did it seem related to? Are you systemically unwell? Known allergies
Is there a genetic association in atopic eczema?
Yes, there’s a genetic predisposition
Elicit from family history
What is the atopic triad?
Asthma
Hay fever
Eczema
What are the clinical features of atopic eczema?
Moderate itchiness Erythematous Diffuse Flexural - on thinnest skin Worse in winter because dry Worse in summer because of heat
What are the environmental triggers of atopic eczema?
Irritants Allergy Heat Infection Itch-scratch cycle Stress and anxiety
Where is atopic eczema found on an infant, compared to adults?
Often on extensor surfaces, rather than flexural surfaces
What is discoid eczema?
Eczema in annular disk-like patches
What does discoid eczema mimic?
Psoriasis
Tinea
What does discoid eczema respond to?
Potent topical steroids
What is asteatotic eczema?
Cobblestoned dry skin
Worse on front of legs of elderly patients
What does asteatotic eczema respond to?
Emollients - keeps barrier intact to avoid infections
Topical steroids
What is pompholyx?
Vesicular hand (and foot) eczema
What can precipitate pompholyx?
Excessive washing
Sweating
How is pompholyx treated?
Potent topical steroids
How is pompholyx prevented?
Avoidance of - Detergents - Soaps - Irritants Regular emollients
What is diffuse erythrodermic eczema?
Severe eczema - >90% of body surface area Significant morbidity Usually infected with Staphylococcus Can be - Tachycardic - Hypotensive - Septic shock
What is the treatment of diffuse erythrodermic eczema?
Hospital admittance
Intense topicals
Systemic immunosuppression
What are the complications of eczema?
Bacterial superinfection
Eczema herpeticum
Contact dermatitis
What happens in bacterial superinfection of eczema?
Eczematous skin lacks natural antibacterial peptides
Often superinfected with S aureus - produces golden crust
What is the treatment for bacterial superinfection of eczema?
Systemic anti-Staph antibiotics
30 mL of bleach in 30-40 L bath > bathe children > can decrease high Staph load
What is eczema herpeticum?
Secondary infection by HSV pf eczematous skin
What are the clinical features of eczema herpeticum?
Dermatomal pattern Intensely painful vesicles Sudden onset Worsening of pre-existing eczema Punched out erosions
Why is eczema herpeticum an emergency?
Risk of corneal scarring
Needs urgent assessment by ophthalmologist
What is the treatment for eczema herpeticum?
Systemic antiviral treatment
What is the difference between allergic and irritant contant dermatitis?
Allergic = your own immune system reacting to a substance Irritant = affects everyone; eg: dipping your hands in hydrochloric acid
What is used to diagnose allergic contact dermatitis?
Patch testing
What are the general measures for the treatment of atopic eczema?
Avoid soap
Regular emollient
Warm, not hot showers
What are the specific treatments for atopic eczema?
Topical steroid to inflamed areas
Mild steroid for face/non-steroidal anti-inflammatory creams
Treat infection with systemic antibiotics
What are the other treatment options for atopic eczema?
Wet dressings
Phototherapy with UVB
Systemic immunosuppression
In whom is psoriasis more common: children or adults?
Adults
What is the distribution pattern of psoriasis?
Symmetrical
Around joints
- Affects joints too
What are the clinical features of psoriasis?
Genetic predisposition Age of onset - 20s - 50s Extensor rash Symmetrical Silvery scale Well demarcated Itchy, but not primary complaint, like in eczema Erythematous/salmon pink
Describe flexural and genital psoriasis
Affects only certain flexural surfaces, like - Under breasts - Around groin - Around gluteal cleft Flatter and less scaly
Describe palmar-plantar psoriasis
Painful
Can develop quite deep fissures
Bacterial infections through damaged skin barrier
Extreme swelling can lead to infarcts
- Grossly swollen hands medical emergencies
- Sometimes surgical emergencies
What are sterile pustules?
Full of pus, but just part of inflammatory response, not response to infection
What is post-streptococcal guttate psoriasis?
1-2 weeks after Streptococcus URTI/tonsillitis
Sudden generalised onset of small plaque psoriasis
Most will clear with treatment
Recurs if Streptococcus infection again
What is the treatment for post-streptococcal guttate psoriasis?
Very responsive to phototherapy
What is generalised pustular psoriasis?
Acute pustular flare of psoriasis Often accompanied by systemic symptoms - Fever - Chills Loss of - Barrier function - Thermoregulation - Protein Risk of - Pre-renal impairment - High output cardiac failure - Sepsis Hospital admission to stabilise
How do you treat psoriasis?
Depends on severity and comorbidities Topical Phototherapy Systemic Often used in combination
What are the topical treatments of psoriasis?
Steroids Tars Calcipotriol Dithranol Keratolytics Emollients
What are the phototherapy treatments of psoriasis?
Narrowband UVB treatment
What are the systemic treatments of psoriasis?
Oral acitretitin
Methotrexate
Cyclosporin A
Biological treatments
What are the causes of acne?
Starts in adolescence - Increasing sebum production Can be flared by - Hormonal factors - Picking - Emotional stress Medications - Lithium - Anabolic steroids - Topical corticosteroids Topical occlusion - Oily makeup - Moisturisers - Headwear - Hairstyling
What are the four parts of acne?
Abnormal keratinisation of sebaceous duct
Colonisation with Propionobacterium acnes
Increase in androgen levels > increased sebum production
Inflammation
What are blackheads?
Open comedone
- Oxidised sebum
What are whiteheads?
Closed comedone
What is hormonal acne?
Premenstrual flare
Mainly on lower face
What is the treatment of hormonal acne?
Anti-adrogenic OCP +/- anti-androgen
What may hormonal acne associated with other features like hirsutism and androgenetic alopecia suggest?
PCOS
What is rosacea
2 parts - both can occur at same time/in isolation
- Vascular reactivity = redness and flushing
- Inflammatory rosacea = papules and pustules
What triggers vascular reactivity in rosacea?
Sunlight Alcohol Hot foods and drinks Spicy foods Emotion Heat Topical steroids can worsen
What are the long-term complications of rosacea?
Vascular dilatation - Redness - Telangiectasia Tissue hypertrophy - Rhinophyma
What is the management of rosacea?
Avoid triggers Vascular rosacea - Vascular laser Inflammatory rosacea - Topical metronidazole gel - Topical azaleic acid - Systemic antibiotics - Systemic isotretinoin Rhinophyma - Ablative laser - Surgery
What are the clinical features of scabies?
Intensely itchy rash Starts on - Hands - Interdigital spaces - Feet Itch worse at night Spreads to - Genital areas - Generalised body rash Spares face and head in adults Other close contacts develop itch after few weeks
How is scabies treated?
Treat all close contacts at same time - Sexual contacts - Household contacts Index case retreated after 1 week Post-scabies itch takes weeks to settle 5% permethrin Apply cream all over from neck down Leave on overnight Wash off in morning Treat clothing - Hot wash - Tumble dry
