Other Eczematous Disease Flashcards
What two age groups are most commonly affected by seborrheic dermatitis?
Infants and adults, rarely kids
Pathogenesis of seborrheic dermatitis
Altered sebum and Malassezia spp
Most common areas affected by seborrheic dermatitis?
Scalp, ears (external canal retroauricular fold), medial eyebrows, upper eyelids, nasolabial folds, central chest and major body folds
First-line agents of seborrheic dermaittis?
Topical antifungal creams and shampoos, selenium sulfide or zinc shampoo’s, mild topical CS for face and body folds, moderate strength topical CS for scalp and ears (fluocinonide)
-2nd line: topical tacrolimus ointment (stings)
Diseases associated with severe seborrheic dermatitis?
HIV infection and neurological disease
Risk factors for asteatotic eczema?
Winter weather, dry weather, and increased age
Posterior axillary line involvement can be seen in what eczematous diseases?
Can be seen in chronic GVHD or asteatotic eczema
What is an Id reaction?
Systemic eczematous reaction to a previously localized dermatitis. Can also be a rebound phenomenon from a rapid CS taper.
Areas favored by Id reaction?
Symmetric extensor surfaces of extremities, palms and soles
What are the two entities which most often trigger id reaction?
Allergic contact dermatitis and stasis dermatitis
Clinical of nummular dermatitis
- Doesn’t need the atopic march, coin-shaped lesions 2-3 cm in diameter commonly on the arms in women, but all extremities can be involved.
- Has erythematous border
- Chronic relapsing course
What must be seen for the dx of HTLV-associated infective dermatitis?
+ HTLV-1 serology
What age group most affected by HTLV-associated infective dermatitis?
Neonates, infants, rare in adults
Clinical of dyshydrotic eczema?
Firm extremely pruritic vesicles of palms>soles and on lateral and medial aspects of the digits
What medication can trigger dyshidrotic eczema?
IVIG
Triggers for dyshydrotic eczema?
Stress, allergic or irritant contact derm, IVig
Tx of dyshydrotic eczema?
Potent topical CS, topical tacrolimus (first line), PUVA, and systemic CS
Clinical of juvenile plantar dermatosis?
Dry and scaly skin w/ mild inflammation and “glazed” appearance on bottom of feet. +/- painful fissures on feet.
What is juvenile plantar dermatosis caused by?
Hydration of the corneal layer 2/2 wearing impermeable shoe materials –> shearing from the friction of softened corneum–> usually only seen in children w/ atopic diathesis.
Treatments for juvenile plantar dermatosis
Synthetic socks, keeping feet dry
Most common cause of diaper dermatitis ?
Irritant contact (urine, stool, etc)
What type of milk is a/w less candida diaper dermatitis?
Breast fed –> cow’s mild fed kids have more urease producing bacteria –> more basic and then you get more candidiasis
3 most common causes of diaper dermatitis?
Irritant contact dermatitis, candidiasis, seborrheic dermatitis
Less common causes of diaper dermatitis?
Bacterial infections (bullous impetigo, streptococcal perianal dermatitis and intertrigo), psoriasis, allergic contact dermatitis, atopic dermatitis
Rare causes of diaper dermatitis?
Dermatitis enteropathica, early kawasaki, langerhans histiocytosis
What is one of the most common allergens for contact dermatitis in the genital area?
Wipes! (Kathon CG, methychloroisothiazolineone / methylisothiazolinone)
Way to differentiate candida in the groin from tinea cruis
Candida has satellite lesions and it involves the scrotum. Candida should also be thought of when you see spreading at the periphery
Most common species of candida in the diaper area?
C. Albicans or C. Tropicalis
Most common bulleous dermatosis of children?
Bulleous impetigo, and autoimmune: linear IgA
What toxins cause bullous impetigo?
S. aureus produces exfoliatoxins A and B (ETA and ETB) this cleaves desmoglein-1–> sub corneal inter granular acntholysis w/ neutrophil iseen in blister cavity on histology. This is the same mechanism as staph scalded skin but is localized
Treatment for bullous impetigo?
Topical mupirocin, retapamulin or fusidic acid. If widespread IV antibiotics
Epi of perianal strep?
Children>>>adults
What do you call seb derm that is on the chest
Petaloid
what is the gold standard tx for infantile seborrheic dermatitis?
Topical ketoconazole
What is disseminated eczema/autosensitization?
It can be a rebound phenomenon from rapid CS taper or a reaction to a previously localized dermatitis.
Most common locations for autosensitization reactions?
Symmetric extensor surfaces of extremities, palms, and soles.
What are the two most common causes of id reaction or autosensitization?
Allergic contact dermatitis and/or venous stasis dermatitis.
Presentation of HTLV-1 associated dermatitis?
Presents with exudative and crusty eczematous dermatitis of scalp, ears, eyelid margins, paranasal skin, axillae, and groin.
What test is required for HTLV-1 associated dermatitis?
HTLV-1 serology
What are endemic areas for HTLV-1?
Africa, NE South America, Caribbean basin, southern Japan, and Iran
What are some potential triggers for dyshidrotic eczema?
Stress, allergic or irritant contact dermatitis, administration of IVIg, a/w atopic dermatitis and hyperhidrosis
Why does candida secondary infection happen with diaper dermatitis?
You get a more basic pH environment (urine and ureases from fecal bacteria) which then leads to candidiasis.
Babies fed what are at higher risk of getting candidiasis?
Cow-milk fed. Babies fed cow’s milk have more urease-producing bacteria –> more basic environment.
What areas are spared in irritant diaper dermatitis?
The genitocrural folds.
Presentation of diaper area candidiasis?
Intense erythema, satellite pustules/lesions, fabors folds, genitals.
Seborrheic dermatitis presentation in the diaper area?
Well-demarcated salmon-colored to red moist or scaly patches and plaques
Favors folds involvement of other sites.
Clinical presentation of asteatotic dermatitis?
Dry skin with cracking (looks like cracked river bed), erythema, and scale
-Can have oozing and crust
Symptoms and distribution of asteatotic eczema?
Usually is itchy and favors the lower legs
Histology of steatotic dermatitis?
Xerosis (compact corneum) and spongiosis
Treatment for asteatotic eczema?
Emollients are key to tx and prevent flairs (apply immediately after bathing)
- Avoid aggravating factors
- Topical CS and TCI
Morphology/presentation of nummular eczema?
Round or coin-shaped pink plaques, of on extremities
- Very pruritic
- Can look acute (eczematous) or chronic (lichenified)
Treatment of nummular dermatitis?
Mid to high potency TS (ointments preferable to creams), TCI’s and phototherapy
What is progesterone dermititis?
Cyclic flares of dermatitis during the luteal phase of the menstrual cycle
Starts 1 week prior to menses –> resolves a few days after menses
If you have a women who is noting flares of eczematous dz a week prior to her period and it resolves after her period what test would you do to confirm dx?
Intradermal injection of progesterone –> induces skin reaction
What are the treatments for progesterone dermatitis?
OCP’s, tamoxifen to inhibit ovulation
What is a major ddx item for progesterone dermatitis and how do you tell these apart?
Estrogen dermatitis
-These can be compared b/c estrogen dermatitis gets wore just prior to menses, intradermal estrone test can identify
What is the pathophysiology of statsis dermatitis?
Swelling promotes venous HTN which leads to capillary distention and leak. The fluids, plasma, proteins, and erythrocytes cause edema –> fibrosis, ulceration, inflammation, and microangiopathy
Where does stasis dermatitis often start?
Often starts on the medial ankle or the distal third of leg
What is occurring if the legs start to take the shape of an “inversted wine glass” in the setting of chronic stasis dermatitis?
Lipodermatosclerosis (stasis panniculitis)
-This is caused by the chronic inflammation leading to a tight cuff of adherent skin/subcutaneous tissue to the fascia
What can be seen in the setting of chronic stasis dermatitis?
Atrophie blanche, ulceration
-These are from the venous changes, often occur on the supra malleolar region
(compare with livedoid vasculopathy)
What is the histology of stasis dermatitis?
Lobular capillary hyperplasia +/- vessel cuffing; hemosiderin and fibrosis of dermis and subcutaneous fat septae
Treatment of stasis dermatitis?
Treat venous HTN w/ compression and elevation. Treat the skin component w/ emollients and topical CS
How long after the initial triggering condition does ID reaction occur?
Days to weeks after primary lesion
What are the most common causes of contact urticaria?
In Finland: Cow dander> natural rubber latex> Flour/grain/feed
What are the risk factors for contact urticaria?
AD, hand dermatitis, and allergy to fruits (Kiwi, avocado, banana, and melon)
What is the pathogenesis of contact urticaria?
Mediated by allergen-specific IgE on mast cells which leads to the release of histamine
Common food-based causes of contact urticaria?
Potato, celery, raw meat, fish, shellfish
What is the most common cause of contact urticaria in healthcare workers?
Latex
What patients are at higher risk of contact urticaria from latex?
Patients with spinal bifida and those with atopic dermaittis
What type of reaction is more common for latex?
Type I is much more common than type IV
What are things that can increase the risk of anaphylaxis from latex allergy?
Aerosolized glove powder or mucosal exposure
What things cross-react with latex?
“BACK Passion”
Banana
Avocado
Chestnut
Kiwi
Passion fruit
What is the difference between contact urticaria immunological and non-immunologic mediated?
The non-immunologic is caused by something directly driving the skin response (i.e. nettles)
What are the most common causes of non-immunologic contact urticaria?
Urticaceae/stinging nettles and jellyfish
Pathophysiology of non-immunlogic contact urticaria?
Triggers (nettles etc) trigger the release of histamine, acetylcholine and serotonin
What types of things can cross-react with contact urticaria and a reaction to birch pollen?
Apples, pears, and cherries (and others)
What test should be used for contact urticaria?
The open patch test
- The open part means that you apply the substances directly to the forearms and wait ~30 min to see if there is a response if nothing can wait 30 min longer
- This is better than prick, scratch, and intradermal testing as these cna lead to anaphylaxis
What is the treatment of contact urticaria?
Antihistamines, avoid trigger, epi and supportive care if anaphylaxis
What are the changes to the sebum noted in seborrheic dermatitis?
Increased triglycerides/cholesterol and decreased squalene and FFA
Cholesterol is usually the lowest part of sebum and triglycerides are usually the most abudant followed by squalene
What is the histology of seborrheic dermatitis?
Psoriasiform acanthosis, spongiosis, “shoulder parakeratoissi<” superficial perivascular/perifollicular lymphocytic infiltrate
What is the gold standard treatment for seborrheic dermatitis?
Topical azoles
- Can also use ciclopirox, topical CS, TCI, zinc/selenium sulfide shampoos, coal tar shampoos, mineral oil for babies
What areas are favored in the pediatric population for seborrheic dermatitis?
Scalp (cradle cap), body creases (posterior neck, scalp, face, postauricular, presternal, and intertriginous areas (grown, axillae, popliteal fossae too)
