Dermatology Flashcards
Eczema
A chronic atopic condition caused by defects in the normal continuity of the skin barrier, leading to gaps which allow irritants, microbes and allergens to enter, creating an immune response and leading to inflammation.
Environmental Triggers for Eczema
changes in temperature, certain dietary products, washing powders, cleaning products and emotional events/stress.
Symptoms of Eczema
Usually in infancy - Dry, red, itchy skin with sore patches over the flexor surfaces (elbows, knees) and face and neck - Often episodic with flares
Management of Eczema
For maintenance, emollients e.g. E45, Diprobase should be used as often as possible, especially after washing and before bed which help create an artificial barrier over the skin
How should Eczema flare ups be treated?
- Flare ups can be treated with thicker emollients such as Cetraben ointment or topical steroids such as Hydrocortisone and Betnovate (beclomethasone) which help keep moisture locked in overnight - Other specialist treatments include topical tacrolimus, oral corticosteroids and methotrexate.
Stevens-Johnson Syndrome
A disproportional immune response causing epidermal necrosis resulting in blistering and shedding of the top layer of the skin - less than 10% of body surface area affected
Aetiology of Stevens-Johnson Syndrome is mainly down to 2 things - which are?
Medications + Infections
Medication causes of Stevens-Johnson Syndrome
- Anti epileptics - Antibiotics - Allopurinol - NSAIDs
Infectious causes of Stevens-Johnson Syndrome
Herpes simplex
Mycoplasma pneumonia
Cytomegalovirus
HIV
Symptoms of Stevens-Johnson Syndrome
- Some cases will be mild whilst others will be severe and potentially fatal
- Non-specific symptoms initially with fever, cough, sore throat, sore mouth, sore eyes and itchy skin
- Purple/red rash which spreads across the skin and blisters, this then breaks away and leaves the raw tissue underneath
- Pain, blistering and shedding can also happen to the lips and mucous membranes
- Inflammation and ulceration of the eyes can also happen - It can also affect the urinary tract, lungs and internal organs
Managment of Stevens-Johnson Syndrome
Medical emergency: supportive care is essential - Steroids, immunoglobulins and immunosuppressant medications can all be given with specialist guidance
Complications of Stevens-Johnson Syndrome
Secondary infection such as cellulitis, sepsis - Permanent skin damage
What is allergic rhinitis?
Allergic rhinitis is an IgE-mediated hypersensitivity reaction of the nasal mucosa to allergens, leading to symptoms such as sneezing, nasal congestion, rhinorrhea, and itchy eyes or nose.
What are the two types of allergic rhinitis?
Seasonal allergic rhinitis (hay fever) – occurs during specific pollen seasons.
Perennial allergic rhinitis – occurs year-round due to allergens like dust mites, pet dander, or mold.
What are the common allergens causing allergic rhinitis?
Pollen
Dust mites
Animal dander
Mold spores
What is the pathophysiology of allergic rhinitis?
Allergens trigger IgE production, leading to mast cell activation and the release of histamine, leukotrienes, and prostaglandins. This causes inflammation and typical allergy symptoms.
List the risk factors for allergic rhinitis.
Family history of atopy (e.g., asthma, eczema)
Exposure to allergens
Urban living
Presence of other atopic conditions
What complications can arise from untreated allergic rhinitis?
Chronic sinusitis
Nasal polyps
Otitis media with effusion
Sleep disturbances
Allergic rhinitis is mediated by __________ and involves hypersensitivity reactions.
IgE
__________ is a major risk factor for developing allergic rhinitis, especially in individuals with asthma or eczema.
Family history of atopy
Common nasal symptoms of allergic rhinitis include __________, __________, and __________.
Sneezing, nasal congestion, rhinorrhea
The __________ test is used to confirm allergen-specific IgE levels in allergic rhinitis.
Skin prick
Nasal corticosteroids like __________ are first-line treatments for moderate to severe allergic rhinitis.
Fluticasone
Which of the following is NOT a common symptom of allergic rhinitis?
A. Sneezing
B. Nasal congestion
C. Chest pain
D. Rhinorrhea
C. Chest pain