Other eczematous disorders Flashcards
Infantile and adult forms of seb derm, talk about epidemiology?
infantile form self limited and within first 3 months of life
adult form is chronic, with peak in 4th-6th decades
no genetic predisposition, no horizontal transmission
Extensive or therapy resistant = HIV related
Which yeast is implicated in seb derm?
What is the implicated path (two main factors)
Malassezia furfur
- M. Furfur likely acts as an opportunistic pathogen → patient has enlarged sebaceous glands, overproduce sebum which leads to overproduction of m. furfur
- Imbalance of skin flora/ altered composition of skin lipids → TGs/ cholesterol elevated, squalene/ FFAs decreased
Bonus, P. Acnes is decreased in seb derm pts
Describe seb derm lesions
Sharply demarcated patches or thin plaques varying from pink-yellow to dull red/ red brown with greasy scales/ flakes
predilection for sebum rich areas scalp, face, ears, presternal, intertriginous
Pruritus/ burning is common
Triggers of seb derm
Stress
Immunosuppression
Sun exposure
Heat
Fever
Associated diseases with seb derm
HIV
Parkinsons
Epilepsy
differentiating between psoriasis and seb derm on scalp
psoriatic lesions more circumscribed, thick silvery plaques - typically less itchy, lesions on body, nail changes
differential of seb derm on scalp
psoriasis, seb derm, chronic contact dermatitis, tinea capitis
Facial seb derm differential
Rosacea
Actinic keratoses
Lupus
Dermatomyositis (heliotrope rash often more violaceous)
Tinea faciei ( typically more annular, asymmetic dist. on cheek)
diagnosis of Seb Derm
KOH prep (spaghetti and meatballs, hyphae/ spores)
Biopsy
HIV testing
Histology of seb derm
Treatment of Seb derm→
Scalp vs face vs infants
Scalp: topical selenium sulfide shampoo, Ketoconazole shampoo, ciclopirox, salicylic acid, tar shampoo
2-3 x weekly for 5-30 minutes
Face: Topical antifungals (ketoconazole Vs. Ciclopirox +2.5% Hydrocortisone
Infants: No tear shampoo → selenium sulfide
Key features of Asteatotic eczema
Affects aging adults >60 yo
AKA Eczema Craquele
Dry, rough, scaly and inflamed skin with superficial cracking
Predilection on shins, lower flank, posterior axillary line
a/w aging, xerosis, low humidity, frequent bathing
Xerosis of aging skin pathogenesis
deficient intercellular lipids in stratum corneum
Altered ratio of fatty acids esterified to ceramide
persistence of corneodesmosomes + premature expression involucrin and formation of cornified envelope
Describe the lesions/ what is the condition
Asteatotic eczema (Eczema Craqeuele)
- Diffuse xerosis w/ fine scale progresses to inflammation/ cracking of skin like porcelain*
- Eventually may cause fissuring/ pruritus*
What endocrine factors/ diseases can exacerbate regular xerosis and cause asteatotic eczema?
Hypothyroidism
Renal failure
Liver DZ
malnutrition (Zinc)
HIV
Sjogren’s (ANA)
Treatment of Asteatotic eczema
mild topical steroids
Regular use of emollients, urea-, ceramide-, lactic acid containing preparations, bath oils
topical calcineurin inhibitors
What is this disease and what are the clinical features?
Nummular dermatitis - eruption of round (discoid) eczematous patches almost exclusively of the extremities , often lower legs of men/ forearms & hands of women
The lesions are well demarcated, 1-3cm, sometimes acutely inflamed with vesicles/ weeping
more often lesions are lichenified plaques/ hyperkeratotic
usually pruritic with excoriations present
CHRONIC
Histological features of nummular dermatitis
Irregular acanthosis of the epidermis is accompanied by marked spongiosis as well as parakeratotic scale and crust. A lymphohistiocytic infiltrate is present in the dermis with a few lymphocytes within the epidermis. Edema is present in the papillary dermis.
HTLV-1 induces proliferation followed by receptor expression and increased secretion of ______________
Induces spontaneous T cell proliferation with increased IL2 receptor expression, IL2 secretion, IFN gamma, IL5 and IL10, IL 6 and TNF alpha raise subsequently
HTLV associated infective dermatitis criteria
Eczema of head/neck, scalp, ears, eyelids, paranasal skin, axilla, groin, chronic watery nasal discharge, chronic relapsing dermatitis , numerous lab findings
dishydrotic eczema is / isnt related to issues with sweat glands?
Not associated with
Is associated with atopic dermatitis, usually a late stage finding
however hyperhidrosis may exacerbate the condition
Explain this histology
Clinically, firm vesicles are seen along the side of the thumb and thenar eminence. Some of them are deep-seated. B Histopathologically, spongiosis within the epidermis is accompanied by macrovesicles; the thickened stratum corneum points to an acral location.
Dermatitis that arises simultaneously at non-sites of contact is referred to as
Disseminated Eczema aka Autosensitization
(Id reaction)
What is this, talk about the pathology
Juvenile plantar dermatosis
- Erythema and scaling of the plantar foot*
- Histologically similar to stasis dermatitis*
Enclosed environments (boots) causes humid environment/ friction leading to hyperhydrosis of the horny layer and when the corneum layer is rubbed off it leads to glazed skin + xerotic cracks
Differential Ddx of diaper dermatitis
