Other eczematous disorders

Question 1

Infantile and adult forms of seb derm, talk about epidemiology?

Answer 1

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

Question 2

Which yeast is implicated in seb derm?

What is the implicated path (two main factors)

Answer 2

Malassezia furfur

1. M. Furfur likely acts as an opportunistic pathogen → patient has enlarged sebaceous glands, overproduce sebum which leads to overproduction of m. furfur
2. Imbalance of skin flora/ altered composition of skin lipids → TGs/ cholesterol elevated, squalene/ FFAs decreased

Bonus, P. Acnes is decreased in seb derm pts

Question 3

Describe seb derm lesions

Answer 3

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

Question 4

Triggers of seb derm

Answer 4

Stress

Immunosuppression

Sun exposure

Heat

Fever

Question 5

Associated diseases with seb derm

Answer 5

HIV

Parkinsons

Epilepsy

Question 6

differentiating between psoriasis and seb derm on scalp

Answer 6

psoriatic lesions more circumscribed, thick silvery plaques - typically less itchy, lesions on body, nail changes

Question 7

differential of seb derm on scalp

Answer 7

psoriasis, seb derm, chronic contact dermatitis, tinea capitis

Question 8

Facial seb derm differential

Answer 8

Rosacea

Actinic keratoses

Lupus

Dermatomyositis (heliotrope rash often more violaceous)

Tinea faciei ( typically more annular, asymmetic dist. on cheek)

Question 9

diagnosis of Seb Derm

Answer 9

KOH prep (spaghetti and meatballs, hyphae/ spores)

Biopsy

HIV testing

Question 10

Histology of seb derm

Question 11

Treatment of Seb derm→

Scalp vs face vs infants

Answer 11

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

Question 12

Key features of Asteatotic eczema

Answer 12

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

Question 13

Xerosis of aging skin pathogenesis

Answer 13

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

Question 14

Describe the lesions/ what is the condition

Answer 14

Asteatotic eczema (Eczema Craqeuele)

• Diffuse xerosis w/ fine scale progresses to inflammation/ cracking of skin like porcelain*
• Eventually may cause fissuring/ pruritus*

Question 15

What endocrine factors/ diseases can exacerbate regular xerosis and cause asteatotic eczema?

Answer 15

Hypothyroidism

Renal failure

Liver DZ

malnutrition (Zinc)

HIV

Sjogren’s (ANA)

Question 16

Treatment of Asteatotic eczema

Answer 16

mild topical steroids

Regular use of emollients, urea-, ceramide-, lactic acid containing preparations, bath oils

topical calcineurin inhibitors

Question 17

What is this disease and what are the clinical features?

Answer 17

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

Question 18

Histological features of nummular dermatitis

Answer 18

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.

Question 19

HTLV-1 induces proliferation followed by receptor expression and increased secretion of ______________

Answer 19

Induces spontaneous T cell proliferation with increased IL2 receptor expression, IL2 secretion, IFN gamma, IL5 and IL10, IL 6 and TNF alpha raise subsequently

Question 20

HTLV associated infective dermatitis criteria

Answer 20

Eczema of head/neck, scalp, ears, eyelids, paranasal skin, axilla, groin, chronic watery nasal discharge, chronic relapsing dermatitis , numerous lab findings

Question 21

dishydrotic eczema is / isnt related to issues with sweat glands?

Answer 21

Not associated with

Is associated with atopic dermatitis, usually a late stage finding

however hyperhidrosis may exacerbate the condition

Question 22

Explain this histology

Answer 22

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.

Question 23

Dermatitis that arises simultaneously at non-sites of contact is referred to as

Answer 23

Disseminated Eczema aka Autosensitization

(Id reaction)

Question 24

What is this, talk about the pathology

Answer 24

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

Question 25

Differential Ddx of diaper dermatitis