What are the characteristics of Pityriasis Alba?
Mild form of Atopic Dermatitis Commonly presents as hypopigmented macules on the face and neck.
What is a simple drug eruption?
ACDR that is limited to the exanthem (skin) only.
What findings would indicate Chronic Urticaria?
If the individual lesions resolve within 24-48 hours, but the reaction continues for >6 weeks. Also, there are no confounding symptoms such as arthralgias or fever.
What is a complex drug eruption?
ACDR that has constitutional symptoms (multi system)
Describe Steven-Johnsons Syndrome and Toxic Epidermal Necrolysis.
They are the same condition, TEN is more severe. Acute, life-threatening reactions to drugs (occasionally idiopathic) Result in extensive necrosis and detachment of the epidermis.
A severe allergic reaction with life-threatening systemic findings, mainly laryngospasm, airway obstruction, vascular collapse, and hypotension. Usually occurs within 1 hour of exposure.
What medications can be used for atopic dermatitis?
Antihistamines - for itching Skin hydration - emollients and limited use of soap Topical calcineurin inhibitors - for itching, not for use on children
How should emergency department care begin for a patient with anaphylaxis?
O2 2 large-bore IVs for hypotension IV antihistamines IV steroids
What type of reaction is an ACDR?
Most are hypersensitivity, immunologic reactions, varying widely between Type I, II, III, and IV
What precautions should patients at risk for anaphylaxis take?
Carrying an epinephrine auto-injector
How do you diagnose ICD?
Through the history and clinical exam
How may SJS or TEN present?
Begin as target-like lesions or diffuse erythema. Progress to necrosis and epidermal detachment.
What is the Nikolsky sign/phenomenon?
Where the epidermis is dislodged from the dermis when rubbed laterally with your hand. May be seen in EM Major.
What findings would indicate Acute Urticaria?
If the individual lesions resolve within 24-48 hours and the overall reaction resolves in
How do you manage Acute Urticaria?
Remove triggers Antihistamines - H1 blockers for skin and vasculature, reducing pain, itching, and edema H2 blockers - parietal cells (stomach) Corticosteroids (prednisone) - short oral course
How do you manage Chronic Urticaria?
Remove triggers. Refer all cases that are not Acute or Physical. Antihistamines - H1 blockers for skin and vasculature, reducing pain, itching, and edema H2 blockers - parietal cells (stomach)
What findings would indicate Physical Urticaria?
If the individual lesions AND the overall reaction resolves within 2 hours (such as sweat, cold, solar...)
What are symptoms of chronic ICD?
painful burning and itching USUALLY evolves through several stages: chapping, hyperkeratosis with scaling, fissures, and crusting
Where does atopic dermatitis commonly manifest on the body?
Commonly found on the face and flexor surfaces, neck, dorsa of feet and hands
What age group is commonly affected by Pityriasis Alba?
What type of hypersensitivity response can you generally use antihistamines with to treat symptoms?
Type I Immediate - usually involves release of histamines
What are the symptoms of atopic dermatitis?
Pruritic (itchy), excoriated inflammation of the skin Poorly defined erythematous patches, papules, and plaques that may result in a puffy appearance. Linear or punctate erosions develop from scratching. Infants, scaling and wet crusts are common.
What is hypersensitivity?
a local or generalized reaction following contact with a specific allergen to which previous exposure and sensitization has occurred.
Describe Lichen Simplex Chronicus.
Manifests as a chronic patch of lichenification that forms from repetitive rubbing or scratching. This patch has a hypersensitive itch response, which creates a habit of rubbing or scratching that continues its cycle.
Which form of ICD is the most common, acute or chronic?
Chronic. Frequently seen on hands of people exposed to wet work
How do you manage ACD?
Burow's solution Topical glucocorticoids (ointments preferred over creams) Prednisone - severe cases Oral soporific antihistamines - may help patient sleep
Describe Erythema Multiforme
A cutaneous reaction to antigenic stimuli (autoimmune). May present as a drug reaction or bacterial organism, but MOST COMMONLY a reaction to herpes simplex virus.
What is a Type I Immediate hypersensitivity response?
IgE mediated (antibody) reaction that occurs within minutes of exposure.
What are examples of common irritants/toxic agents?
soaps, detergents, cement, petroleum, acetone, fiberglass, wool, friction, pressure
A pruritic skin eruption characterized by transient, blanchable wheals of varying shapes and sizes that may become confluent. Usually resolves in 48 hours