DERM Flashcards
What is the definition of urticaria (hives)?
Local or generalized superficial swelling of the skin due to an allergic reaction.
What is the first-line management for urticaria?
Non-sedating antihistamines (e.g., loratadine or cetirizine).
Sedating antihistamines (e.g., chlorphenamine) can be considered at night.
What is the management if urticaria is severe?
Oral prednisolone for severe cases.
What are the common characteristics of the rash in urticaria?
- Pruritic (itchy)
-Pale pink raised lesions
What is the definition of Herpes Zoster (Shingles)?
Acute infection caused by reactivation of varicella zoster virus (VZV), which causes chickenpox and lies dormant in the dorsal root.
Clinical diagnosis is made by the rash.
What are the risk factors for Herpes Zoster?
Age, HIV, immunosuppression (e.g., long-term steroids).
What are the key features of Herpes Zoster?
- Unilateral, dermatomal rash (most common T1-L2)
- Prodromal pain (burning sensation over dermatome)
- Rash: initial erythematous macules that progress to vesicular rash
- If rash around eye/tip of nose → Herpes Zoster Ophthalmicus
How do you manage Herpes Zoster?
- Antivirals (oral aciclovir) within 72 hours
- Analgesia (NSAIDs, neuropathic agents, oral corticosteroids if severe)
- Patient is infectious until vesicles have crusted over after 1 week
- Neuralgia post-infection is common but resolves within 6 months; give neuropathic painkillers.
What is the vaccination approach for Herpes Zoster?
- Primary VZV infection vaccination for healthcare workers who are not naturally immune.
- Reactivation vaccination for all individuals aged 70+.
What is Pityriasis Versicolor?
A superficial cutaneous fungal infection caused by Malassezia furfur, leading to patches of hypopigmented, pink, or brown rash, typically on the trunk. May scale.
How do you manage Pityriasis Versicolor?
First-line treatment: topical antifungal (e.g., ketoconazole shampoo).
If not responsive, perform skin scraping and consider oral antifungal treatment.
What is Tinea?
A term used for dermatophyte fungal infections (does not include Pityriasis/Tinea Versicolor).
Known as ringworm, commonly caused by Trichophyton species.
What is Tinea Capitis?
Fungal infection of the scalp, often caused by Trichophyton tonsurans.
Presents with itchy scalp and hair loss.
Diagnosis: scalp scraping.
Management: topical antifungal shampoo or oral antifungal.
**You wear a cap on your scalp **
What is Tinea Corporis?
Fungal infection of the trunk, legs, or arms, caused by Trichophyton rubrum and Trichophyton verrucosum.
Features: well-defined annular erythematous lesions, itchy.
Treatment: oral fluconazole.
What is Tinea Pedis?
Also known as athlete’s foot, a fungal infection of the feet.
Features: itchy, peeling skin between the toes.
Management: topical antifungal cream.
What is Scabies?
A skin infection caused by the Sarcoptes scabiei mite. Characterized by an itchy rash, often accompanied by burrows, especially in the interdigital webs, wrists, and fingers.
What is the pathophysiology of Scabies?
The mites burrow under the skin, lay eggs, and cause further infection. It is highly contagious, so inquire about contact with others.
What is Crusted Scabies?
A severe form of scabies that affects immunosuppressed patients, presenting with scaly patches instead of the usual spots/burrows.
What are the clinical features of Scabies?
PC: Extreme pruritus (itchiness).
O/E: Scratch marks, erythematous raised papules, and linear burrows on fingers, interdigital webs, and flexor wrists.
What is the treatment for Scabies?
First-line: Permethrin 5% cream.
Instructions: Apply to the whole body, leave for 8-12 hours, repeat after 1 week. Itchiness may persist for up to 4 weeks.
What are important management points for Scabies?
Avoid close contact until treatment ends.
Wash everything
Treat all household members and anyone with physical contact.
What is Impetigo?
A superficial bacterial skin infection, very contagious and common in children, caused by Staphylococcus aureus or Streptococcus pyogenes. It can be primary or secondary (e.g., from eczema, bites, or scabies).
What are the clinical features of Impetigo?
O/E: Golden, crusted lesions around the mouth.
Rash: Vesicles may form, leading to bullous impetigo (if caused by Staphylococcus aureus).
What is the treatment for limited, localized Impetigo?
Hydrogen peroxide 1% cream or topical fusidic acid (antibiotic) if not resolving.
What is the treatment for severe or bullous Impetigo?
Oral flucloxacillin.
What is the exclusion policy for Impetigo?
Exclude from school until 48 hours after starting antibiotics.
What is Molluscum Contagiosum?
A skin infection caused by the poxvirus, common in children (1-4 years old), transmitted by close contact or shared surfaces. It belongs to the Poxviridae family.
What are the risk factors for Molluscum Contagiosum?
Atopic eczema is a significant risk factor.
What are the clinical features of Molluscum Contagiosum?
O/E: Clusters of pink/white papules with a central umbilication, making the lesion look like a target.
What is the management for Molluscum Contagiosum?
Generally self-limiting (up to 18 months). No treatment needed, but cryotherapy may be used for cosmetic reasons.
Avoid sharing towels, scratching, and refer HIV patients to a specialist.
What is Lichen Planus?
A skin disorder thought to be autoimmune, often triggered by medication use.
What are the clinical features of Lichen Planus?
Ps: - Purple, Puritic (itchy), Papular (raised), Polygonal lesions
- Wickham’s striae (white lines over the surface)
- Koebner phenomenon (lesions after trauma)
- Oral involvement (white lace pattern)
What is the management for Lichen Planus?
Potent topical steroids
What is Seborrheic Dermatitis?
A chronic dermatitis thought to be caused by an inflammatory reaction related to a proliferation of the normal skin fungus Malassezia furfur.
Associated with HIV and Parkinson’s disease.
What are the clinical features of Seborrheic Dermatitis?
- Itchy rash on the face and scalp, often causing dandruff
- Complications: otitis externa and blepharitis
What is the management for Seborrheic Dermatitis?
- Scalp disease: ketoconazole 2% shampoo
- For other areas: topical antifungal (ketoconazole) + topical steroids (short-term)
What is Bullous Pemphigoid?
Autoimmune condition causing skin blistering, typically in those 60+ years old.
What are the clinical features of Bullous Pemphigoid?
- Itchy, tense blisters
- Mouth spared
How is Bullous Pemphigoid diagnosed?
Skin biopsy
What is the management of Bullous Pemphigoid?
- Topical steroids → oral steroids
- Antibiotics (ABx)
- Immunosuppression
What is the definition of TEN/SJS?
Severe systemic reaction affecting skin and mucosa.
- <10% body involvement = SJS.
- > 30% body involvement = TEN.
What are the common causes of TEN/SJS?
- Penicillin
- Sulphonamides
- Lamotrigine, carbamazepine, phenytoin
-Allopurinol
-NSAID
What are the key features of TEN/SJS?
- Nikolsky’s sign (epidermis splits from dermis → skin peels off)
– Systemically unwell: pyrexia, tachycardia
-Mucosal involvment
- Maculopapular rash with target lesions, progressing to vesicular/bullae
What is the management of TEN/SJS?
- Stop the causative drug
- Hospital admission for supportive care (electrolyte disturbance, volume loss)
- IV immunoglobulin (IVIG) if severe
What is the definition of HSV Eczema Herpeticum?
HSV causing a severe skin reaction.
- More common in children with atopic eczema.
- May be life- and sight-threatening → urgent.
What are the key features of HSV Eczema Herpeticum?
- Small punched-out erosions
What is the management of HSV Eczema Herpeticum?
- IV aciclovir
- Urgent referral
What is the definition of Rosacea (Acne rosacea)?
Rosacea (also known as Acne rosacea) is a chronic skin condition characterized by redness, flushing, and other skin changes on the nose, cheeks, and forehead.
What are the key clinical features of Rosacea?
PC:- Flushing and erythema on the nose, cheeks, and forehead.
-Worsneed by sunlight
Later - papuples and pustules
- Telangiectasia.
- Rhinophyma (enlarged nose)
What is the management of Rosacea?
Conservative:
-sunscreen
Medical
– Flushing/erythema: Topical brimonidine gel (PRN).
Pustules/papules
–Topical ivermectin
- Moderate-Severe: Topical ivermectin + oral doxycycline.
- Telangiectasia: Laser therapy.
- Refer if not improving or for rhinophyma.
What is the definition of Acne Vulgaris?
Acne Vulgaris is a very common condition, particularly in teenagers (80-90%). It results in the formation of keratin plugs with pustules and comedones (blackheads) on the face and upper back.
What is the pathophysiology of Acne Vulgaris?
Inflammation follows colonization by the bacterium Propionibacterium acnes.
There is also an increase in sebum (oil) production by hair follicles, which contributes to the development of acne.
What are the classifications of Acne Vulgaris?
- Mild: Comedones (blackheads).
- Moderate: Widespread non-inflammatory lesions and numerous papules and pustules.
- Severe: Extensive inflammatory lesions with scarring.
What are the clinical features of Acne Vulgaris?
PC:
comedons (blackheads)
inflam papules and pustules
may progress to inflamed cysts
OE
-scarring (ice pick or hypertrophic
- Acne fulminans: Severe acne with systemic features.
What is the management of mild to moderate Acne Vulgaris?
Mild to Moderate:
12 weeks of topical combination therapy
- Fixed combination of topical adapalene + benzoyl peroxide or
- Fixed combination of topical tretinoin + topical clindamycin or
- Fixed combination of benzoyl peroxide + clindamycin.
What is the management of moderate to severe Acne Vulgaris?
Moderate to Severe:
- 12 weeks of topical combination therapy:
-Retinoids (adapalene, tretrinoin)
– Antiseptic (benzoyl peroxide).
- Emollient (azelaic acid).
- ABx (doxycycline, lymecycline, clindamycin).
-Consider COCP
- Never use oral and topical antibiotics together.
What are the indications for specialist referral in Acne Vulgaris?
Refer if:
- Oral isotretinoin needed (contraindicated in pregnancy).
- Failure of 2 cycles of treatment for mild-moderate acne.
- Acne with scarring or mental health issues.
What is the definition of Atopic Dermatitis?
Atopic Dermatitis (also known as eczema) is a common dermatological condition characterized by inflammation of the dermis. It is more common in children and is part of the atopic triad (asthma, eczema, hay fever).
What is the pathophysiology of Atopic Dermatitis?
Atopic dermatitis results from epidermal barrier dysfunction and/or immune dysfunction.
What are the triggers for Atopic Dermatitis?
- Irritants: soaps, detergents.
-Infections
-Extreme temp
-animal hair
-stress
-food /inhaled allergens
What are the clinical features of Atopic Dermatitis?
PC:
- Dry, red skin with poorly defined edges.
- Itchy, with excoriations.
- Adults: often on hands.
- Children: often on face, flexor surfaces (wrist, ankles).
O/E
- If severe, may have blisters, oozing, bleeding.
What investigations are done for Atopic Dermatitis?
If there is suspicion of infection, a skin swab can be done.
Common infections include HSV (leading to eczema herpeticum) and Staphylococcus aureus (leading to impetigo).
What is the management of Atopic Dermatitis?
- Conservative: Avoid triggers, use emollients, and reduce scratching (antihistamines may help).
- Emollients: Large quantities applied to the whole body 3–4 times a day. Examples include Dermol (antimicrobial), E45, Diprobase (thin), and Hydromol (thick).
- Topical Steroids: Used during flare-ups.
Mild - hydrocortisone
Moderate - Eumovate (clobetasnone)
Potent - Betnovate (betamethasone)
Very potent - Dermovate (clobetasol) - Further steps: Wet wrapping (in children), topical calcineurin inhibitors (e.g., tacrolimus), UV therapy, or oral immunosuppression (steroids, ciclosporin, methotrexate).
What is the definition of Psoriasis?
Psoriasis is a chronic skin disorder characterized by red, scaly patches. It is associated with increased risk of arthritis and cardiovascular disease (CVD).
It improves with sun exposure.
What is the pathophysiology of Psoriasis?
Psoriasis is multifactorial, with genetic, immunological factors contributing to the condition.
The exact mechanism is not fully understood but is worsened by various triggers.
What are the types of Psoriasis?
- Plaque psoriasis (most common).
-Flexural
-Guttate - post strep - self limiting
What are the triggers for Psoriasis?
- Skin trauma.
-Stress
-Alcohol - Medications: BB, lithium, anti-malarials, NSAIDs, ACE inhibitors.
What are the clinical features of Psoriasis?
PC:
- Well-demarcated, dry, red, scaly plaques (raised).
- Covered in white scales/flakes.
- Itching possible, no oozing.
- Location: Symmetrical, typically on extension surfaces (elbow, knee), also trunk, scalp, palms, soles.
O/E:
- Nail changes: pitting, onycholysis.
What investigations are done for Psoriasis?
A skin biopsy may be performed to rule out other infections.
What is the management of Psoriasis?
- Regular emollients.
-1st line medical:
- Potent topical steroids + vitamin D analogue (apply OD).
-Dovobet = combo
4 week break between coirses
2nd line medical:
- Vitamin D analogue BD (calcipotriol, calcitriol, tacalcitol).
3rd line
- Potent topical steroid BD or coal tar preparation.
- Phototherapy: UVB therapy, photochemotherapy (PUVA).
- Systemic agents: Methotrexate for flares.
What is the definition of Actinic Keratosis?
Actinic Keratoses (also known as solar keratoses) are premalignant skin changes caused by chronic sun exposure.
What are the features of Actinic Keratosis?
- Small, dry, crusty/scaly skin lesions.
- Colours may include pink, red, brown, or skin-coloured.
- Typically multiple lesions on sun-exposed areas.
- Malignancy red flags: bleeding, rapid change in colour, size, or feeling.
What is the management of Actinic Keratosis?
- Fluorouracil cream (with topical hydrocortisone following).
- Topical diclofenac.
- Consider cryotherapy or cautery for removal.
What is the definition of Dermatofibroma?
Dermatofibroma (also known as histiocytomas) is a common benign fibrous skin lesion, often developing following a precipitating injury.
What are the features of Dermatofibroma?
- Solitary firm nodule.
- Typically located on arms or legs.
- Overlying skin dimples.
What is the management of Dermatofibroma?
Management is generally not required unless cosmetic concerns arise, in which case excision may be performed.
What is the definition of Seborrheic Keratosis?
Seborrheic Keratosis is a common benign skin lesion, often seen in older patients.
What are the features of Seborrheic Keratosis?
- Dark-colored (black-brown) crusty/greasy spot.
- Stuck-on appearance.
What is the management of Seborrheic Keratosis?
Benign; may be frozen off (cryotherapy) if symptomatic or for cosmetic reasons.
What are the risk factors for skin cancer?
- Light skin
-sun exposure
-hx of sunburns
-immunosuppression (POST RENAL)
-previous lesion
-FH
-smoking
What is the skin lesion ABCDE rule for melanoma?
ABCDE:
-Asymmetry
-Border irregularity
-Colour variation
-diameter >7mm
-Evolving
Red flags: Inflammation, bleeding, oozing, or altered sensation.
What is the NICE 7-point checklist for melanoma referral?
Urgent 2-week referral if 3+ points:
- 2 points each: Change in size, shape, or color
- 1 point each: >7mm, inflamed, oozing/bleeding, change in sensation.
What are the types of melanoma?
- Superficial spreading melanoma: Most common, grows relatively slowly, often in younger people.
- Nodular melanoma: Aggressive, associated with sun exposure, red/black lump, may bleed.
-Lentigo Maligna
-Acral lentiginous melanoma
What is the management for melanoma?
- Excision biopsy
-Claculate Breslow thickness
What are the features of SCC (Squamous Cell Carcinoma)?
- Rapidly expanding
-ULCERATED, may bleed
-sun exposed areas
What is the management of SCC?
- Excision biopsy
What are the features of BCC (Basal Cell Carcinoma)?
- Pearly or pale papule with raised edges
-Telangiectasia
-Ulcercation may occur
What is the management of BCC?
- Routine referral for:
- Cryotherapy, surgical removal, topical cream, or radiotherapy
