Dermatology Flashcards
What endocrine diseases are associated with acanthosis nigricans?
Diabetes and GI cancer
What condition is dermatitis herpetiformis associated with?
Coeliac
What are the key characteristics of the rash associated with lupus?
Rash is associated with photosensitivity, alopecia, livedo reticularis, and Raynaud’s phenomenon.
SLE investigations
Diagnosis involves testing for antinuclear antibodies (ANA) and anti-double-stranded DNA (anti-dsDNA).
SLE management
prednisolone for systemic lupus erythematosus (SLE) and betamethasone 0.1% cream for discoid lupus erythematosus (DLE).
What is a common cause of erythema multiforme, and how is it treated?
Erythema multiforme is often caused by herpes simplex infection. Treatment options include clobetasol 0.05% cream or prednisolone.
Which body parts are affected by erythema multiforme?
Minor cases involve the hands/feet, while major cases present with systemic symptoms and mucosal involvement.
What conditions are associated with pyoderma gangrenosum?
ulcerative colitis (p-ANCA) and Crohn’s disease
How does pyoderma gangrenosum present and how is it managed?
Enlarging painful ulcers - prednisolone
What are the key features of dermatomyositis?
Myositis (muscle weakness), a photosensitive rash (shawl sign), Gottron papules, and nail fold erythema
How is dermatomyositis diagnosesd?
creatine kinase (CK), antinuclear antibodies (ANA), anti-Jo-1
What are the common causes of erythroderma?
Erythroderma can be idiopathic or result from psoriasis, dermatitis, or drugs.
How does erythroderma present?
Generalized erythema affecting more than 90% of the skin, and patients may feel cold despite the skin feeling hot.
What drugs commonly cause Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN)?
Allopurinol, sulphonamides, NSAIDs, and anticonvulsants
What is the causative organism of necrotizing fasciitis?
Streptococcus pyogenes
Clinical features of necrotising fascitis
Pain out of proportion, dusky purple rash and oedema progressing to blisters and necrosis
How is localised impetigo treated?
Fusidic acid cream
What is the causative organism of impetigo?
Staphylococcus aureus
How is widespread impetigo treated?
Oral flucloxacillin
How is dermatophytosis (tinea) treated?
Terbinafine 1% cream
What is the clinical presentation of varicella zoster?
Pyrexia followed by a macular-papular-vesicular pruritic rash
What are the common areas affected by dermatophytosis (tinea)
Feet (athlete’s), hands, groin
How is Varicella zoster treated
Calamine lotion
What are the treatment options for head lice infestation?
Dimeticone 4% lotion or malathion 0.5% liquid
Where is plaque psoriasis commonly found on the body?
Extensor surfaces, sacrum, scalp
What is seen in psoriasis?
Red scaly plaque
What is the associated risk with leukoplakia?
Squamous cell carcinoma
What are the key features of acne rosacea?
Flushing, telangiectasia, photosensitive erythema, papules, and pustules
What virus is associated with Kaposi’s sarcoma, and in which context is it commonly seen?
Kaposi’s sarcoma is associated with Human Herpesvirus 8 (HHV-8). It is commonly seen in immunocompromised individuals, especially those with HIV/AIDS.
What is the most common type of skin cancer?
Basal cell carcinoma
How does basal cell carcinoma present?
Grows slowly over time
How is Bowen’s disease related to actinic keratoses?
Bowen’s disease is considered squamous cell carcinoma in situ
What are the characteristics of squamous cell carcinoma (SCC), and how does it typically grow?
It grows quickly and often presents as a raised lesion with crusting and ulceration. Surgical excision is the primary treatment.
Scoring system used to calculate quantity of fluid required in first 24 hours after a burn
Parkland criteria
What advice should be given to someone with a herpetic cold sore?
Avoid kissing babies while you have the lesion
How does psoriasis appear on black skin vs white
Purple rather than silver scales
Which medications may exacerbate psoriasis
Beta blockers and aspirin
Management plan for severe urticaria
Non-sedating antihistamine e.g. citirazine + short course of oral steroids
Most aggressive type of melanoma
Nodular
Wallace’s rule of 9s in burns
9% for each arm; 18% for anterior torso
What is the Parkland formula - used to calculate the fluid requirement in burns
4ml x body weight (kg) x total body surface area affected (%)
- Give 50% of this in first 8 hours and rest in the remaining 16
Name 2 features you would assess for in your history and examination that
would be suspicious for potential smoke inhalation
- Burning sensation in the nose / throat
- Productive cough
- Stridor
- Dyspnoea
- Rhonchi
- Wheezing
- Hoarse voice
- Accessory muscle usage
- Tachypnoea
- Cyanosis
- Odynophagia
- Headache
- Delirium
- Hallucinations
- Decreasing consciousness / comatose
- Convulsions / seizures
- Hypertonia
- Facial burns / loss of facial or intranasal hair
- Soot in mouth or sputum
How carbon monoxide affects the oxyhaemoglobin dissociation curve
Carbon monoxide has a greater affinity for haemoglobin than oxygen (so readily binds to Hb)
Causing the curve to shift to the left
Left shift → increased affinity of haemoglobin for oxygen / so haemoglobin holds onto oxygen more tightly
Reducing the release of oxygen to tissues, causing hypoxia and the associated symptoms
Which gene is associated with IBD, psoriasis, ankylosing spondylitis
HLA B27
Define the appearance of chronique plaque psoriasis
- Found on extensor surfaces / elbows + knees / trunk / scalp
- Symmetrically distributed
- Raised
- Clearly defined plaques / clear delineation
- Pink or red / erythematous/ violet or grey in pigmented skin
- Silvery scales
- Itch
- May become fissured / painful (in certain sites)
- 1cm - a few cm in diameter
- Auspitz sign / pinpoint bleeding points if scale is removed
