Eczema and Glandular Disease Flashcards
Two types of contact dermatitis?
irritant and allergic
Which is more common - Irritant or allergic contact dermatitis?
Irritant - 80%
Allergic - 20%
Definition of Irritant Contact Dermatitis?
Direct contact of the skin when an irritant directly damages the skin
Etiology of Irritant contact dermatitis?
- disruption of normal skin barrier triggers inflammation.
- almost any material may be a cutaneous irritant with sufficient exposure in time and/or concentration .
- most common irritants are dry air, water, soap, solvents.
Epidemiology of irritant contact dermatitis?
- Those with light-colored/fair skin are at greatest risk.
- Occurs at any age, more frequent in elderly who have thinner skin.
- More common in women due to environmental factors.
Pertinent history of Irritant contact dermatitis?
- sufficient exposure to a cutaneous irritant
- itching and pain caused by fissuring of skin
- symptoms occurs within minutes to hours of exposure in acute ICD; symptoms may be delayed by weeks in cumulative ICD
- common in occupations that involve repeated hand washing or exposure of the skin to water, food materials, and other irritants.
Exam findings for Irritant contact dermatitis?
- erythematous patches, hyperkeratosis (thickening of skin), or fissuring
- may be well-demarcated (well-defined)
Tx options for irritant contact dermatitis?
- withdrawal of offending agent
- moisturizers
- use of bland cleansers instead of soap
- topical steroids
- avoid abrasive cleansers that traumatize the skin
Definition of allergic contact dermatitis?
Direct contact of the skin with an allergen provokes an immune reaction
Pathophys of allergic contact dermatitis?
- delayed sensitivity reaction to an allergen
- once an individual is sensitized to an allergen, ACD develops within hours to days of exposure.
- memory T cells persist in the dermis after ACD clinically resolves.
Epidemiology and common allergens of allergic contact dermatitis?
no racial, age, or gender predilection
ACD is 1 of the 10 leading occupational illnesses.
Common allergens: poison ivy/oak/sumac, nickel,dyes, fragrances, cosmetics, rubber, preservatives, formaldehyde (common in clothing), neomycin (antibiotic in neosporin), leather, topical steroids, benzocaine, thimerosol (mercury based preservative)
Pertinent hx for allergic contact dermatitis?
intensely itching
rash occurs within 12-48hrs of exposure
ask about profession/hobbies
sx may improve on weekends and holidays
Diagnosis technique for allergic contact dermatisis?
patch testing for chronic cases non-responsive to traditional treatment
Treatment options for allergic contact dermatitis?
avoidance: sx resolve 2-4wks after exposure stops
topical steroids; oral steroids for severe cases
topical immunomodulators (can be used on more sensitive areas where you wouldn’t want to use steroids-face, eyelids, etc.)
oral antihistamines (avoid topical antihistamines)
wet compresses
phototherapy
What is the most common type of non-scarring hair loss?
androgenic alopecia
(male/female pattern baldness)
Male/female exam findings for androgenic alopecia
M: bitemporal recession, frontal or vertex thinning, or total hair loss sparing occipital and temporal regions
F: diffuse thinning around the crown
Treatment options for androgenic alopecia
- topical minoxidil solution (Rogaine)
- finasteride (males only)
- antiandrogens (females only)
Description of androgenic alopecia cause
Combined effect of a genetic predisposition and the action of androgren on the hair follicles of the scalp
Exam findings for alopecia areata
- one or multiple focal areas of smooth hair loss
- typically involves the scalp, but can affect any area of the body
- no scarring or atrophy
- nail pitting may occur in 30% of cases
Ways to treat alopecia areata
There is no cure so treatments are aimed at management. Hair is likely to grow back on its’ own, but intralesional steroid injections, corticosteroids, or minoxidil can be used.
Diagnosis of alopecia areata
Hx and PE
(a gentle hair pull with reveal 10+ anagen or telogen hairs per pull)
Define Atopic Dermatitis
An inflammatory, chronic, pruritic skin disorder
Discuss the pathophysiology of Atopic Dermatitis.
Defective barrier of the skin leads to the entry of antigens.
Various antigen react with antibodies to produce increased levels of IgE.
Pts may have genetic predisposition to react to various antigens.
Pts may have defective lipid production.
Discuss the etiology of Atopic Dermatitis.
The skin of pts is colonized by Staphylococcus Aureus bacteria.
Sxs may flare in extreme climates, with the interaction of wool, or various food such as soy, eggs, meat, milk or fish.
What is hyperhidrosis and what causes it?
- Sweating in excess of that required for normal thermoregulation (glandular disease)
- Common, chronic idiopathic condition (no known cause)
- Could be result of metabolic or neurologic disorder, febrile illness, malignancy, drug side effects
What pt population is most suseptible to Atopic Dermatitis?
8-25% of people worldwide have atopic dermatitis.
The disease is equal among races and genders.
It is more common in children than adults.
Personal or family history of asthma, allergic rhinitis or hayfever.
Common characteristics of hyperhidrosis, including age of onset and location on the body?
- Excessive sweating that impairs daily activities
- At least 1 episode/wk for 6 months
- Onset before age 25 (later onset should prompt search for secondary cause, like malignancy or neurological issue)
- Focal sweating (localized to one area) that stops during sleep
- Bilateral and relatively symmetric; usually affects axillae, palms, and/or soles
Clinical presentation of Atopic Dermatitis?
Xerotic, erythematous, scaly, lichenified, ill-defined plaques and patches.
Incessant pruritis.
More common in fexure folds or creases, but can be present anywhere.
May be associated with Dennie-Morgan folds (see pic), allergic conjunctivitis, or hyperlinear palms.
How is Atopic Dermatitis dx?
Clinical presentation, Hx, PE
Can check IgE levels
Allergy testing is not extremely helpful.
Hyperhidrosis dx, tx, prognosis
- Dx based on Hx and PE
- Tx
- Topical aluminum chloride (drysol or Xerac)
- iontonphoresis
- botulinum toxin
- anticholineragic or sympathectomy for severe
- Prognosis: difficult to treat but newer therapies are beginning to offer better prognosis