Dermatology Flashcards
Dermatitis
- Dermatitis or eczema is a pattern of cutaneous inflammation that presents with erythema, vesiculation, and pruritus in its acute phase
- The chronic phase is characterized by dryness, scaling, lichenification, fissuring, and pruritus
Multiple types of dermatitis:
o 1. Seborrheic
o 2. Atopic
o 3. Dyshidrotic
o 4. Nummular
Seborrheic Dermatitis
- Affect person in post puberty
- Pityrosporum Ovale, lipophilic yeast of Malassezia genus
- May induce inflammatory response
- Present on all person
- Responds to antifungal
- Infancy and adolescence
CLINICAL PRESENTATIONS of Seborrheic Dermatitis
Affect area where sebaceous blends in high frequency and are most active
♣ Scalp
♣ Eyebrows
♣ Eyelashes
♣ Forehead
♣ Nasolabial fold (common in kids with CP)
♣ External ear canal
Also found near umbilicus, under breast
Treatment for Seborrheic Dermatitis (4)
- Under androgen control - responds well to anti-fungal shampoo
- Frequent cleansing with soap removes oils
- Outdoor recreation improve seborrhea
- Avoid sun damage
Antidandruff Shampoo
- 2.5% percent selenium sulfide
- 1-2% pyrithione zinc
- Head and Shoulders
- Coal Tar
- OTC Ketoconazole shampoo treats the fungus infection; can rotate with Coal Tar
Some popular name brands - Antidandruff shampoo
OTC with salicylic acid –> X-Seb, Scalpicin Pyrithione Zinc 1% –> Head and shoulder, Zincon, Dandex Pyrithione Zinc 2% –> DHS zinc, Theraplex Z Prescription medicine selenium sulfide Selsun, Exsel) or pyrithione zinc DHS Zinc, Head & Shoulders Shampoos with coal tar DHS Tar, Neutrogena T/Gel, Polytar may be used 3 times a week Carmol HC ♣ Contains urea smoothing agent; takes top layers of skin and smooth them down ♣ Not aesthetic because urea burns Elidel off-label use; calcium inhibitor and very good for seborrhea (BBW and high lymphoma risk)
TREATMENT: Special Considerations for African Americans Seborrheic Derm
- Use of daily shampooing not applicable
- Weekly shampooing
- Fluocinolone acetonide in oil as pomade
- Other option
- Moderate to mid potency topical
- Corticosteroid in ointment base
- Some AA children do not wash hair everyday because it would dry out
- Use with mid-strength steroid to clear it up
Contact Dermatitis 2 types
Skin condition created by a reaction to an externally applied substance
Types of contact dermatitis:
o Irritant Contact Dermatitis (ICD)
o Allergic Contact Dermatitis (ACD)
Allergic Contact Dermatitis Overview
- ACD occurs when contact with a particular substance elicits a delayed hypersensitivity reaction
- The sensitization process requires 10-14 days
- Upon re-exposure, dermatitis appears within 12-48 hrs
- The most common cause is Rhus dermatitis, from poison ivy, poison oak, or poison sumac (all contain the resin – urushiol) T-cell mediated***
Other common causes of A Contact Derm (9)
o Fragrances
o Formaldehyde
o Preservatives
o Neosporin
o Benzocaine
o Vitamin E
o Rubber compounds
o Nickel – Number 1 contact dermatitis
o Balsam of Peru – ALL MAKE-UP**
Clinical Findings of Atopic Contact Dermatitis
- Main symptom of ACD is pruritis
- Weepy, huge amounts of vesicles Bilateral
- Presents as eczematous, scaly edematous plaques with vesiculation distributed in areas of exposure
- ACD is bilateral if the exposure is bilateral (e.g., shoes, gloves, ingredients in creams, etc.)
Poison oak leaves are usually (5)
o Are 3‐7cm in length
o Lobulated notched edges
o Groups of 3, 5, or 7
o Grows on bush‐like plants
o Turn colors in autumn
Poison Ivy leaves are usually
o Are 3‐15cm in length
o Notched edges o Groups of 3s
o Grows on hairy‐stemmed vines or low shrubs
o Turn colors in autumn
LEAVES OF 3 LET THEM BE
Rhus Allergy Initial episode
Subsequent outbreaks
Total length Initial episode
- The initial episode occurs 7-10 days after exposure
- On subsequent outbreaks the rash may appear within hours of exposure and usually within 2 days
- Individual sensitivity is variable so the eruption may be mild to severe
- Rhus dermatitis lasts from 10-21 days depending on the severity
- Initial episode is the longest (up to 6 weeks!)
What should you use for drying weeping allergic contact derm?
BURROWS solution – covered under medicaid phenomenal for drying up weeping allergic contact dermatitis
Linear Streaks
Koebner phenomenon
Fomites can be contaminated by…
the plant oil and lead to recurrent eruptions
Contact dermatitis; topical steroid level
3 along with anti-itch medication (aveeno, eucerin)
Rhus Dermatitis Mimics of Lesions – Bullous insect bites (3)
o Usually scattered
o Not linear or grouped
o No history of multiple bites
Rhus Dermatitis Mimics of Lesions – Cellulitis
- Spreading erythematous, non-fluctuant tender plaque
- Can be associated with fever
Rhus Dermatitis Mimics of Lesions – Herpes Zoster
Painful eruption of grouped vesicles in a dermatomal distribution
Rhus Dermatitis Mimics of Lesions – Urticaria
o MOVING edematous plaques, not vesicles
o Early lesions of allergic contact dermatitis could be mistaken for urticaria
Rhus Dermatitis Treatment
- Most patients need minor supportive care
- Topical steroids for localized involvement
- Topical or oral antihistamines may improve pruritus
- Oatmeal soaks/calamine lotion may soothe weeping erosions
- Severe involvement may require oral steroids
- In cases of failing potent topical steroids, or widespread
- If given for less than 2-3 weeks, patients may relapse
- Do not give short bursts of steroids for this reason
Rhus Allergy Prevention
- Avoid the plants
- Wash clothing, shoes, and objects after exposure (within 10 minutes if possible)
- Apply barrier: clothing, OTC products which bind resin more than skin
Eyelid Allergic Contact Dermatitis Common Causes
Intensely pruritic
- Scaling red plaques on upper > lower eyelids
- Allergic contact dermatitis of the eyelid is often caused by transfer from the hands
- Common causes:
- Nail adhesive/polish
- Fragrances and preservatives in cosmetics – Balsam of Peru
- Nickel
Evaluation of Dermatitis
- • Important to take a comprehensive history
- Ask questions about possible culprit
- Think about what they might be doing
- Complete dermatologic assessment of the patient
- Shape, configuration, and location of the dermatitis are useful clues in identifying the culprit allergen
- Elimination of a suspected trigger may be both diagnostic and therapeutic
- In chronic cases, patch testing is necessary to identify specific allergens
HISTORY TAKING FOR Dermatitis
o In addition to the dermatitis-specific history (e.g., onset, location, temporal associations, treatment), be sure to ask about:
- Daily skin care routine
- All topical products
- Occupation/hobbies
- Regular and occasional exposures (e.g. lawn care products, animal shampoos)
Are they washing their dog with flea shampoo? Hobby, recreation
Steroid Potency
Regular use of Class 1, 2, or 3 steroids on thin skin will lead to steroid atrophy (thinning and easy bruising/purpura)
o Also hypopigmentation in darker skin types
If topical steroids are to be used on the eyelid for a period of more than one month, refer to an ophthalmologist for monitoring of intraocular pressure and the development of cataracts
Steroid Potency FOR THE FACE
For the face:
- Class 6, 7 steroids (e.g., desonide) can safely be used intermittently during flares
- Hydrocortisone cream 1%
- Elidel and protopic (Black Box Warnings) ELIDEL – Works for contact derm around eyes
PATCH testing (6)
- Patch testing is used to determine which allergens a patient with allergic contact dermatitis reacts against
- A series of allergens are applied to the back, and they are removed after 2 days
- On day 4 or 5, the patient returns for the results
- Positive reactions show erythema and papules or vesicles
- Identification of specific allergens helps the patient find products free of those allergens
- Example of a patient with patches (allergens) placed on the back o Best test for allergic contact dermatitis
POSITIVE PATCH TEST
Positive patch test reactions at 96-hour reading
This patient had three positive reactions
♣ Nickel, Balsam of Peru, and Fragrance Avoidance of these allergens should improve their rash
Identifying Allergens
- Not all patients with ACD need patch testing
- Refer patients when the allergen is unclear or the dermatitis is chronic
- A positive reaction on patch testing does not mean that the patient’s rash is due to that specific allergen
- Elimination of the rash with removal of the allergen confirms the clinical relevance of the positive patch test
ACD Treatment
- Avoid exposure to offending substance
- Treatment of the acute phase depends on the severity of the dermatitis
- In mild to moderate cases, topical steroids of medium to strong potency for a limited course is successful
- A short course of systemic steroids may be required for acute flares
- Oatmeal baths or soothing lotions can provide further relief in mild cases
- Wet dressings are helpful when there is extensive oozing and crusting BURROWS*
Chronic cases or patients with dermatitis involving over _____ of the BSA should be referred to a dermatologist
10%
Latex Allergy
- Delayed hypersensitivity: Patients develop an allergic contact dermatitis
- Often presents on the dorsal surface of the hands
- Immediate hypersensitivity: May present with immediate symptoms such as burning, stinging, or itching with or without localized urticaria on contact with latex proteins
- May include disseminated urticaria, allergic rhinitis, and/or anaphylaxis #1 allergen that will go from a localized reaction to systemic reaction
- Can get type 1 reaction after years of having a type 4 T-cell mediated allergic reaction
S from SCRATCH
- stands for symmetrical.
- Commonly affected areas include exposed surfaces such as the face, neck, arms, and legs
- Covered areas such as the abdomen, palms, soles, diaper area, etc. are spared. C stands for cluster.
- Lesions usually appear in a “meal cluster,” that is often described as “breakfast, lunch, and dinner.” This grouping of lesions are characteristic of bedbug bites, but also are seen in flea bites and with IBIH.
- Appear in a meal cluster; breakfast, lunch and dinner
R stands for
- Rover
- Is there is a family pet where the child could come into contact with fleas?
A stands for
- age.
- IBIH is rarely seen in babies, and these reactions peak after the age of 2.
T stands for
- Target and time.
- Target lesions are characteristic for IBIH, particularly in dark‐pigmented patients. Time refers to the chronic nature of this condition.
C stands for
- confused.
- Patients and their parents are often confused/surprised that these reactions are due to bugs.
H stands for
- history.
IBIH is not often associated with family history, unlike with scabies and atopic dermatitis where we see a strong family history correlation
3 P’s for Insect Bites
- Prevention
- Wearing protective clothing for outdoor play with use of insect repellents.
- Patience
- Pruritis control
- Topical steroids may help
- Due to depth of inflammatory, topical agents can ineffective.
- Use of antihistamine
- Little evidence to support due to the predominance of T‐cell–mediated response and a lack of histamine‐mediated lesions.
- Topical steroids may help
Irritant Contact Dermatitis
Overview
- Inflammatory reaction in the skin resulting from exposure to a substance that can cause an eruption in most people who come in contact with it
- Strictly on hands – most likely irritant contact dermatitis
- No previous exposure is necessary
- May occur from a single application with severely toxic substances
- Most commonly results from repeated application from mildly irritating substances (e.g., soaps, detergents)
Multifactorial disease where…
Most important exogenous factor for ICD
Areas that are most susceptible
- Multifactorial disease where both exogenous (irritant and environmental) and endogenous (host) elements play a role.
- Most important exogenous factor for ICD is the inherent toxicity of the chemical for human skin
- Site differences in barrier function, making the face, neck, scrotum, and dorsal hands more susceptible
Major Risk Factor for Irritant Hand Derm
-
Atopic dermatitis is a major risk factor for irritant hand dermatitis because of impaired barrier function and lower threshold for skin irritation
- More likely to get irritant CD
- When you go to apply a moisturizer for atopic derm you need to be careful because if they do travel – using a moisturizer that doesn’t have a lot of chemicals in it
ICD Clinical Findings
- Mild irritants produce
- Erythema
- Chapped skin
- Dryness
- Fissuring after repeated exposures over time
- Pruritus can range from mild to extreme
- Pain is a common symptom when erosions and fissures are present
- Severe cases present with edema, exudate, and tenderness
- Potent irritants produce painful bullae within hours after the exposure
What to use for Itch (5)
- Topical steroids
- Antihistamines
- Only provide relief when pruritus is mediated by antihistamine as in case of urticaria
- Eczema—anti histamine does not work
- Pramoxine
- Topical anesthetic
- Aveeno anti itch
- Eucerin calming cream
- Pramasone
- Topical anesthetic
- Capsaicin
- Capzasin cream activate the TRP-V1 channel to produce mildly painful sensation and interferes with itch
- Used for bug bite*
- Menthol
- Topical ant-itch product—Sarna, and aveeno
- Activates TRP channels to create a competitive sensation to itch
- Vicks vapor rub
ICD Evaluation and Treatment
- Identification and avoidance of the potential irritant is the mainstay of treatment
- Need to avoid whatever causes it
- Topical therapy with steroids to reduce inflammation and emollients to improve barrier repair are usually recommended
- Referral to a dermatologist should be made for patients who are not improving with removal of the irritant or in severe cases
- Patch testing should be performed in occupational cases with suspected chronic irritant dermatitis to exclude an allergic contact dermatitis
- PATCH to ALLERGY
ICD prevention
- Patient Education about things the irritant is included in
- Need to read and be able to look for it
- Use personal protective equipment (e.g. protective gloves should be worn for any wet work)
- Instead of soap, use less irritating substances, such as emollients and soap substitutes when washing
- Only recommend: White Dove for soap
- Care should be taken for several months after the dermatitis has healed, as the skin remains vulnerable to flares of dermatitis for a prolonged period
Take Home Points
- Allergic contact dermatitis (ACD) and Irritant contact dermatitis (ICD) are the two types of contact dermatitis.
- ACD occurs when contact with a particular substance elicits a delayed hypersensitivity reaction.
- ACD = delayed T-cell hypersensitivity reaction
- Most patients need minor supportive care, but some cases will require oral steroids.
- Patch testing is used to determine which allergens a patient with allergic contact dermatitis reacts against.
- Not all patients with ACD need patch testing.
- Latex allergy may present as a delayed or immediate hypersensitivity.
- Can go from type 4 to type 1 anaphylaxis
- ICD is an inflammatory reaction in the skin resulting from exposure to a substance that can cause an eruption in most people who come in contact with it.
- Inflammatory
- Identification and avoidance of the potential irritant is the mainstay of treatment.
- Patch testing may be performed in cases with suspected chronic irritant dermatitis to exclude an allergic contact dermatitis.
- If a rash is due to an exposure at work, the medical evaluation may be covered by worker’s compensation.
- Important to ask about the patient’s occupation/school related activity
- Referral to a dermatologist should be made for patients with contact dermatitis who are not improving with the removal of the allergen/irritant or severe cases.
