Eczematous Disorders Flashcards
Eczematous disorders
Eczema Nummular dermatitis (non-atopic) Asteatotic eczema Dermatitis & eczema of the hands Dermatitis & eczema of the lower legs Dermatitis & eczema of the eyelids Juvenile plantar dermatosis
Eczema
SYMPTOMS
Itch —> may disturb sleep
Soreness
SIGNS Erythema Dryness Excoriation Exudation Fissuring Hyperkeratosis/scaling Lichenification Papulation Vesiculation
ACUTE vs CHRONIC
Acute —> oedematous, vesicular, exudative
Subacute = acute eczema failed to clear almost completely in 3-4 weeks
Chronic —> erythema, scaling, excoriation, lichenification
SECONDARY DISSEMINATION
autosensitisation/autoeczematisation
Often preceded by exacerbation at the primary site
Especially likely if primary site legs/feet
Feet —> hands
Hands —> feet
Secondary eruption features - initial small oedematous papules —> grouped papulovesicles (rarely macules/wheals) —> confluent in small plaques —> symmetrical
Course of secondary eruption depends on progress of primary lesion
Inflamed primary lesion —> secondary eruption increases in severity, may generalise —> possible erythroderma
Primary lesion settled —> secondary eruption subsides
Primary lesion relapses —> secondary eruption recurs readily
CONDITIONED HYPERIRRITABILITY
Phenomenon where an area of inflamed skin on 1 part of body results I’m generalised hyperirritability of the skin at distant sites
eczematous individuals more vulnerable to mild primary irritants i.e. false positive “irritant reactions” to APT/“angry back syndrome”
HISTO (acute phase) -
Spongiosis —> discrete spongiotic epidermal vesicles (palms, soles —> large by coalescing vesicles)
+/- Subcorneal pustules if infected
Lymphocyte exocytosis +/- polymorphs if infected
Lymphohistiocytic infiltrate in dermis +/- polymorphs +/- eos
Vascular dilatation
HISTO (subacute phase) - Parakeratosis Acanthosis Spongiosis, vesiculation diminish Vascular dilatation
HISTO (chronic phase) - Hyperkeratosis replaces parakeratosis Acanthosis > spongiosis Lichenification (rete ridges become elongated and broadened) —> particularly prominent in atopic eczema Lymphohistiocytic infiltrate in dermis Vascular dilatation
CLASSIFICATION (aetiology +/- site) Exogenous eczemas - ACD Irritant eczema Dermatophytide Infective dermatitis Post-traumatic eczema Photoallergic contact eczema Eczematous polymorphic light eruption
Endogenous eczemas - Atopic eczema Asteatotic eczema Nummular dermatitis Eyelid eczema Hand eczema Juvenile plantar dermatosis Pityriasis alba Seborrhoeic dermatitis Venous eczema Chronic superficial scaly dermatitis Metabolic eczema/eczema assoc with systemic disease
GENETICS fillagrin loss of function mutations linked to barrier impairment - - hand eczema - ICD - ACD d/t nickel/other allergens
ENVIRONMENTAL TRIGGERS (Note occupation and recreational activities - relevant)
Irritants —> ICD
Allergens —> ACD
COMPLICATIONS
reduction of skin barrier function —> increases risk of bacterial, viral secondary skin infection
Eczema herpeticum linked to atopic eczema + fillagrin mutations
COURSE/PROGNOSIS
chronic relapsing remitting
INVESTIGATIONS
Clinical dx
Total IgE —> ? Atopic tendency esp if distribution atypical and no background of other atopic illness
Swab MCS if suspect secondary infection —> causative organism, bacterial resistance
Fungal scrapings if suspect dermatophytosis
Dermoscopic exam/scrapings ? scabies
Bx can be helpful to confirm eczema - DIF helpful to exclude DH or pre-bullous Pemphigoid in older patients
APT Main indications - - Atypical eruptions - Asymmetrical eruptions - Facial eczema - Hand eczema - Feet eczema Not routinely indicated for typical endogenous eczema I.e. atopic eczema, pityriasis alba, seborrhoeic dermatitis however maintain low threshold as sensitisation common to topical medicaments —> exacerbate eczema - - fragrances - preservatives - vehicles - epoxy - rubber chemicals Wary of false positive irritant reactions —> conditioned hyperirritability Allow acute eczema to settle before APT
ACUTE ECZEMA MX Rest Elevate affected legs Use affected hands as little as possible Avoid exposures to irritants, allergens Psychological support Derm day unit Soap substitutes Dilute Condys soaks (oedematous, vesicular, exudative eruptions) Liberal bland Emollients Face, genitals - mild to mod TCS Hands, feet - potent, superpotent TCS Trunk, limbs (except hands, feet) - mod, potent TCS \+/- top tacrolimus/pimecrolimus Wet tubular dressings (tubifast) covered with dry layer —> cooling effect When secondary infection or if staph contamination an aggravating factor - - topical antiseptic/antibiotics —> mindful risk of sensitisation, bacterial resistance - oral ABs If excoriated, sedation to reduce this - - sedative antihistamine I.e. phenergan
SUBACUTE ECZEMA MX Derm day unit/admission Avoid exposures to irritants, allergens Soap substitutes Liberal bland Emollients Zinc/coal tar paste bandages (occlude areas that are frequently excoriated I.e. lower leg eczema - ensure firm but not tight to cause discomfort, restrict blood flow) —> soothing, reduce itch TCS under glad wrap occlusion to reduce itch \+/- top tacrolimus/pimecrolimus
CHRONIC ECZEMA MX
Avoid exposures to irritants, allergens
Soap substitutes
Frequent application of bland emollients
Flares - TCS daily according to eczema severity, site, age
After flares - reduce frequency of TCS gradually to prevent rebound flares
Flare prone individuals - twice a week TCS to maintain remission
+/- top tacrolimus/pimecrolimus (if prolonged exposure to TCS on the face to avoid skin atrophy)
Phototherapy - nbUVB, PUVA, UVA1 (chronic eczema resistant to topicals esp atopic eczema)
Oral immunosuppressants -
Systemic CS - acts rapidly 1-2 days, risk of rebound flares
CSA
MTX
AZA
MMF
Alitretinoin for chronic hand eczema
Nummular dermatitis/discoid eczema (non-atopic eczema)
PRESENTATION
Young F
Older M
Circular, coin-shaped, oval plaques of closely-set thin walled vesicles on an erythematous base, with well demarcated edge
Arises rapidly from confluence of tiny papules/papulovesicles
Acute phase —> dull red, exudative, crusted, very itchy
Thereafter —> less vesicular, more scaly, often central clearing , peripheral extension —> ring-shaped/annular lesions
Fades leaving dry scaly patches
Subacute to chronic phase —> secondary lesions occur often mirror-image on opposite side of body
Characteristic for patches that have apparently become dormant may become active again esp if Rx discontinued prematurely
Chronic
Relapses and remissions
Worse during colder months
4 CLINICAL VARIANTS
- Exudative type Nummular dermatitis
- Very itchy
- Resemble acute phase lesions
- Leakage of serous fluid
- Crust
- More severe end of spectrum
- May require PO ABs - Dry type Nummular dermatitis
- Uncommon
- Minimal itching
- Multiple dry scaly oval discs on arms/legs
- Scattered microvesicles on a erythematous base on palms and soles
- More chronic, persists for several years
- Fluctuation/remission
- Rx resistant - Nummular dermatitis of the hands
- Dorsa hands
- Dorsa or sides of fingers
- Single plaque which may occur at site of trauma I.e. burn, local chemical/irritant reaction
- Secondary lesions may occurs on fingers, hands, forearms
- Generalisation uncommon
- Irritant occupational dermatitis, but may also occur w/o occupational exposure
- Atopy frequent - Exudative discoid and lichenoid chronic dermatosis
Extremely itchy
Widespread
Discoid lesions with “lichenoid” + exudative phases (co-exist, or alternate rapidly)
Spontaneous cure after chronic course for months, years
Middle age M Jews
DDX
Tinea corporis (if central clearing)
Psoriasis (scaling more prominent, lesions dry)
Pit rosea (herald patch, Christmas tree pattern)
Pityriasis alba
Chronic superficial dermatitis
Pre-lymphomatous eruption
ASSOCIATIONS
can occur as part of atopic eczema
Total IgE often within normal range
CAUSATIVE ORGANISMS
heavy colonisation of staph may increase severity, even in the absence of clinical evidence of infection
Allergic sensitivity to staph/micrococci may be responsible for secondary dissemination
ENVIRONMENTAL FACTORS Dry skin esp. in elderly Excess ETOH Clinically relevant ACD I.e. - - Rubber chemicals - Formaldehyde - Neomycin - Chromate - Nickel - Cobalt - Fragrance Sensitivity to - - Aloe - Depilatory creams - Oral Methyldopa - Oral Mercury - Oral Gold (dose dependant)
HISTO
subacute dermatitis
Spongiotic vesicles
Lymphohistiocytic infiltrate +/- eos
IX APT if - - unusually severe, persistent - Few patches - Asymmetrical - Unusual configuration
GENERAL MEASURES avoidance of irritants Bed rest Removal from stressful environment Correct low humidity
FIRST LINE
Acute phase - Emollients, potent/very potent TCS +/- topical/oral AB if severe/exudative
Chronic phase - Emolients, coal tar paste + mod potent TCS
SECOND LINE
Topical calcineurin inhibitor
THIRD LINE
Phototherapy (nbUVB, PUVA)
MTX
Pred
Asteatotic eczema/eczema craquele/winter eczema
Eczema developing in very dry skin
Usually elderly
PRESENTATION
Legs, arms, hands of elderly in context of dry skin
Flare during winter d/t reduction in humidity assoc w/ central heating
Dry, slightly scaly
Crazy paving pattern on lower legs —> eczema craquele
Finger pulps dry and cracked, retaining prolonged depression after pressure —> parchment pulps
CLINICAL VARIANTS
Generalised/extensive forms involving trunk, legs —> rare —> consider possible malignancy —> malignancy screen
ASSOCIATIONS May be presenting sign of myxoedema (thyroid disease) Zinc deficiency If generalised/extensive, consider malignancy - - Malignant lymphoma - Angioimmunoblastic lymphadenopathy - Gastric adenoCA - Breast CA
PREDISPOSING FACTORS
ENVIRONMENTAL FACTORS Degreasing agents Diuretics Cimetidine TCS Cold dry winter Installation of central heating
COMPLICATIONS
Secondary infection
Nummular dermatitis
COURSE/PROGNOSIS
If no Rx —> chronic, relapsing each winter, clearing in summer —> permanent
Scratching, rubbing, contact irritants, sensitisers —> spread or diffuse vesiculosquamous eruption
HISTO
Mild subacute eczema
varying amount of dermal infiltrate
IX
Malignancy screen if generalised/extensive
GENERAL MEASURES
Avoid wool (poorly tolerated, may irritate)
Restrict baths, ensure not hot
FIRST LINE
Central heating should be humidified
Avoid abrupt temp changes
SECOND LINE
Bath oils (can be hazardous in elderly as slippery)
Oatmeal packs
Soap substitute
Emollients (paraffin based, urea as a humectant very appropriate) after baths, throughout day —> Restoration of skin hydration
THIRD LINE
Mild TCS
Topical pimecrolimus 1% cream
Juvenile plantar dermatosis/forefoot eczema/dermatitis plantaris sicca/atopic winter feet
PRESENTATION Children 3-14 yrs old Redness SORENESS Plantar surface Forefoot Shiny (glazed), dry fissured dermatitis More severe on ball of foot, toe pads Spares non-weight bearing instep Symmetrical Toe clefts normal (differentiates from tinea pedis) Occasionally affects hands —> sore shiny fissured palms, fingertips
ASSOCIATIONS
Atopy (more likely if affects hands)
ENVIRONMENTAL FACTORS
Friction
Hyperhidrosis
COURSE/PROGNOSIS
Mostly clear spontaneously during childhood/adolescence
At persist into adulthood
IX
Clinical dx
Fungal scrapings may be helpful to exclude tinea
APT may be helpful to exclude footwear allergy if any doubt
HISTO
Mild non-specific eczema
Sometimes blockage of sweat ducts
GENERAL MEASURES/FIRST LINE
Change from non-porous footwear to leather footwear, cotton socks OR open sandals (may not resolve problem)
SECOND LINE
Emollients including urea containing prep (humectant)
THIRD LINE
Lassar’s paste
Coal tar
Topical tacrolimus ointment
Hand eczema
CLINICAL FEATURES
Hands —> Most common site of atopic eczema in adults —> can be isolated atopic eczema
+/- feet
Secondary bacterial infection —> sudden deterioration, pain, exudate
Itch, painful fissuring
Occupation —> improvement with leave from work
Recreational activities
Hand protection strategies
10 CLINICAL VARIANTS
HYPERKERATOTIC PALMAR ECZEMA
Scaly, fissured, hyperkeratotic patches
Palms, palmar surfaces of fingers
Common
POMPHOLYX
Vesicles —> confluence —> large bullae —> +/- hyperkeratotic phase
Palms, soles
If chronic recurrent vesiculation —> chronic vesicular dermatitis
APRON ECZEMA
Proximal palmar aspect adjacent fingers + contiguous palmar skin over MCP joints (“apron”)
Endogenous vs irritant vs allergic
CHRONIC ACRAL DERMATITIS (a syndrome) Middle age persons Very itchy Hyperkeratotic papulovesicular eczema Hands, feet Elevated IgE in context no personal/fam Hx Atopy Poor response to topicals Responds to oral pred
NUMMULAR DERMATITIS (discoid eczema)
FINGERTIP ECZEMA
Palmar surface tips of some or all fingers
Dry, cracked +/- fissured
May merge with palmar eczema
2 patterns -
Most/all fingers of dominant hand, mainly thumb + forefinger —> comulative irritant dermatitis from degreasing agents + trauma —> worse in winter, improves on holiday
Thumb + forefinger + 3rd finger on 1 hand —> usually occupational ICD (newspaper delivery employees) vs ACD (colophony in polish) —> if non-dominant hand, consider onions, garlic held in non-dominant hand —> APT, 20 min contact tests
‘GUT’/SLAUGHTERHOUSE ECZEMA Unknown pathogenesis Workers who enviserate and clean pig carcasses Vesicular eczema Starts in finger webs —> spreads to sides of fingers Self limiting Clear within a week despite ongoing work Recurs in intervals
PATCHY VESICULOSQUAMOUS ECZEMA
Mixture of irregular, patchy vesiculosquamous lesions
Both hands
Assymetrical
RECURRENT FOCAL PALMAR PEELING @ keratolysis exfoliativa
Sometimes a mild form of pompholyx —> some patients develop true pompholyx
Asymptomatic
Little/no irritation
Vesicles not seen
Summer —> abrupt small areas of superficial white desquamation —> Sides of fingers/palms/feet —> expand —> peel off
RING ECZEMA
Young F after marriage/childbirth
Patch of eczema begins under a broad wedding ring —> spreads to adjacent middle finger and palm —> confined vs occasional discoid patches elsewhere vs diffuse vesicular eczema
Nickel, cobalt, chromate sensitivity commonly found on APT
Rarely “white gold” alloys implicated
Fragrance sensitisation
Aetiology - soap/detergent concentrated beneath ring, hot water tightening ring, microtrauma esp friction
DDX hyperkeratotic palmar eczema
Psoriasis -
- Can be difficult to differentiate clinically and histologically
- Silvery scale
- Knuckle involvement
- Sharply demarcated scalloped edges to the erythema along borders of hands and fingers
- Absence of itch
- Nail pits in absence of nail fold inflammation
- Fam Hx psoriasis
Tinea manuum
- Unilateral scaling of palm —> Trichophyton infection
- Discoid plaque —> T verrucosum in farmers
LP
- Margins well demarcated
- Violaceous hue
- characteristic lesions elsewhere
PRP -
- Yellowish orangey hue
- Characteristic lesions elsewhere
DDX POMPHOLYX ECZEMA Palmoplantar pustulosis - Vesicles —> pompholyx - Sterile pustules --> resolve with characteristic brown marks (palmoplantar pustulosis) Pustular bacteride secondary to bacterial infection elsewhere Bullous pemphigoid Pemphigoid gestationis Linear IgA disease
COMPLICATIONS
Secondary bacterial infection
PROGNOSIS
Atopic hand eczema has worse prognosis out of all types of hand eczema
Eczema on dorsal hands clears more readily/less likely to recur that palmar eczema
Interdigital dermatitis in hairdressers —: precursor to more severe dermatitis
ASSOCIATIONS Atopic eczema —> predisposition to discoid pattern of hand eczema Exposures to - - School - Hobby - Occupational irritants
PREDISPOSING FACTORS —> d/t fillagrin mutation - - Naturally dry skin - Atopy - Allergic contact dermatitis - chronic Irritant contact dermatitis - more likely to develop digital fissures/chapping Premenstrual exacerbation Pregnancy deterioration
ENVIRONMENTAL FACTORS Cold and dry air Contact irritants Contact allergens - - Chromate - Epoxy glues - Rubber —> dorsal hands Occupation - - Hairdressers - Caterers/food handlers —> seafood protein —> type 1 reaction —> seafood contact urticaria - Fish industry workers - Farmers - Construction workers - Metal workers - Dental personnel - Medical personnel —> natural rubber latex protein in latex gloves —> type 1 reaction —> contact urticaria, rhinitis, asthma, anaphylaxis Oral ingestion of allergens (controversial) - - Nickel - Chromium - Balsam of Peru
IX
Fungal scrapings to exclude tinea (esp if circumscribed asymmetrical area of scaling/vesiculation on palms/sole
APT as guided by occupation and other allergen exposures to exclude ACD (esp if limited to 1 or 2 interdigital spaces or asymmetrical or involves dorsal hands)
Latex prick testing to exclude type 1 latex hypersensitivity (if immediate symptoms on wearing latex gloves)
Mx hand eczema
MX ACUTE HAND ECZEMA
Avoid contact irritants and allergens
Soap substitutes
If exudative/vesicular —> dilute condys soaks
Copious Emolients
If secondary bacterial infection —> PO fluclox for staph coverage pending swab MCS
MX CHRONIC HAND ECZEMA (persisting for at least 6 weeks)
Hand care advice sheets
Rubber gloves for housework (PVC gloves for rubber allergy) - does not protect against acrylates, epoxy resins
Cotton gloves beneath rubber gloves if sweating beneath gloves makes condition worse
Avoid irritants
Soap substitutes - avoid ones with propylene glycol or alcohol
Frequent emollients - choice depends on max compliance of patient (any emollient is better than none)
TCS for flares (except very mild hand eczema) - potent/superpotent for severe eczema
TCS impregnated tape for painful fissures fingertips
TCS at bedtime under Occlusion with polythene gloves sealed at the wrist with sticky tape for difficult, unresponsive cases —> discontinue as soon as satisfactory improvement d/t risk of atrophy and secondary bacterial infection
If no improvement with TCS —>
- reconsider dx I.e. tinea
- reiterate irritant and allergen exposure
- Contact sensitisation to medicaments bases, preservative, steroid itself —> APT if necessary
Topical tacrolimus 0.1% better for palms > soles
Tar paste for chronic unresponsive cases
Sal acid ointment for hyperkeratosis/persistent scaling
ILCS into recalcitrant localised patches
Iontophoresis for pompholyx
Alitretinoin 30mg daily
Acitretin
AZA 50mg daily
CSA
MTX
Phototherapy - PUVA > nbUVB
Lower legs eczema
Venous eczema/varicose eczema —> skin changes from venous HTN
Stasis dermatitis —> skin changes from reduced lower leg venous flow —> absence of venous HTN
CLINICAL FEATURES
Venous eczema -
- May develop suddenly/insidiously
- Late result of DVT
Overlap between venous eczema, stasis dermatitis —> share same clinical features
Erythematous, scaly, exudative
Ankle, lower leg
Occasionally pendulous skin of obese abdomen, AV fistula upper limb
Accompanied by Other manifestations of venous HTN -
- Varicose veins
- Oedema
- Purpura
- Haemosiderosis
- Ulceration
- “Atrophie blanche” - small patches of white atrophic telengiectatic scarring
+/- purple papules (subepidermal vascular proliferation) around ankles resembling Kaposi sarcoma
CLINICAL VARIANTS
Secondary patches of eczema on other leg
Generalised secondary dissemination —> Erythroderma
DDX
Atopic eczema (children/young adults)
ACD to topical medicaments I.e. paste bandages —> APT
Infected ulcer complicated by infective eczema spreading from edge of ulcer —> respond to appropriate AB
Nummular dermatitis esp anterior/anterolateral aspect
Asteatotic eczema (elderly)
Psoriasis (clear margins, more scaly)
Hypertrophic LP
Dermatophyte/tinea incognito
AKs
Borreliosis (legs feel heavy, thick cyanotic itchy skin)
VENOUS ECZEMA PREDISPOSING FACTORS
Previous DVT
Venous stasis
STASIS DERMATITIS PREDISPOSING FACTORS
Obesity
Immobility
Previous cellulitis
COMPLICATIONS ACD - Eczematous eruption with sharp linear cut-off matching application of topical Rx, wound dressing, compression hosiery - Risk d/t highly inflamed skin/sensitive/primed, prolonged contact with topicals and compression hosiery - Topical ABs - TCS - Preservatives - Fragrances - Rubber accelerators
Secondary infection
- Sudden worsening of eczema
- Pain, increased warmth/swelling, malaise, rigors —> cellulitis
- Mild infection —> Topical ABs
- Mod infection —> PO ABs
- Severe infection —> IV ABs
Bacteria from swab MCS may not be pathogenic
Lipodermatosclerosis
Venous ulcers
- Result of venous HTN
- Healing inhibited by venous eczema, stasis dermatitis d/t chronic LL swelling
COURSE/PROGNOSIS Venous eczema
Chronic, relapses, remissions
Improvement with compression, sometimes varicose vein surgery
IX
ABI prior to graduated compression bandage Rx -
> 0.8 suitable In the Absence of vessel calcification d/t diabetes, atherosclerosis (these can give false high reading)
MX
Control venous HTN
Control pedal oedema
Obese —> Lose weight
Well-fitted support stockings/firm bandages regularly —> mindful to avoid forming a band at the top of the leg (too tight)
Leg elevation
Emolients
TCS - mild TCS to relieve irritation, potent TCS only for a few days d/t risk of atrophy and subsequent ulceration
Topical tacrolimus
ABs for secondary infection - PO may be preferred over topical d/t risk of sensitisation
Paste bandages if trauma playing a part and patient cannot resist scratching
Referral to vascular surgeon for Varicose vein surgery as third line option
Eyelids eczema
CLINICAL FEATURES
Common feature of atopic eczema - can be isolated without other manifestations
Infraorbital Dennie-Morgan fold
Other causes of presentation -
Seb derm
ACD to eye make up components, nail varnish, fragrance, rubber, ophthalmic medicaments
Allergy to nickel in spectacle frames (lower eyelid eczema)
MX Avoid allergens/irritants Emollients Hydrocortisone 1% cream Topical tacrolimus 0.03%-0.1% ointment or Pimecrolimus 1% cream (avoids risk of atrophy, rosacea, raised intraocular pressure assoc with prolonged use of TCS)
Pityriasis alba
CLINICAL FEATURES
Children
Main feature of hypopigmentation
Non well demarcated Rounded, oval irregular hypopigmented patches
Mild erythema, fine scaling usually precedes hypopigmentation
Erythema +/- minimal serous crusting —> erythema completely subsides —> persistent fine scaling + hypopigmentation
Face (cheeks, around mouth, chin)
+/- neck, shoulder, arms
DDX
Vitiligo (depigmentation)
Naevus depigmentosus (single well demarcated lesions on trunk)
Nummular dermatitis (very itchy, larger lesions, more oedematous)
Hypopigmented MF
ASSOCIATIONS
manifestation of atopic eczema but not confined to atopic ppl
COURSE/PROGNOSIS
Variable
Usually lasts ~1 yr
May still show hypopogmentation >12 months after all scaling subsides
Recurrent crops of new lesions
Disappointment response to Rx d/t long time for pigmentation to recover
MX Bland emollient to reduce scaling Mild TCS if inflammed Topical tacrolimus/pimecrolimus Mild tar paste for Chronic lesions on trunk
HISTO Acanthosis Mild spongiosis Hyperkeratosis Patchy parakeratosis \+/- Follicular plugging EM - - Reduced numbers of active melanocytes - Reduced numbers/size of melanosomes
Infective dermatitis/eczema (microbial eczema)
Eczema caused by microorganisms/their products
Bacterial/viral invasion of the skin occuring as the primary event —> followed by secomdary eczematisation beyond the area of infection
I.e. patches of eczema that occasionally develop around lesions of molluscum contagiosum even though MC lesions have not been scratched/traumatised
Eczema clears when the organisms are eradicated/subside
Increased CRP may be useful clue
CLINICAL FEATURES
Advancing erythema +/- microvesicles
Around discharging wounds, ulcers, moist skin lesions
Overgrowth of gram neg organisms —> tinea pedis becomes eczematous
Can complicate pediculosis, scabies, chronic threadworm infestation
Not always clear how much eczematous change is due to scratching, secondary impetigo, direct response to infestation
CLINICAL VARIANTS —> Infective dermatitis of the forefeet Eczema that mainly affects interdigital spaces medial toes Cx staph/strep Respond to antiseptic/ABs Predisposing factors - Poor standard of hygiene - Hyperhidrosis - Heavy footwear
In contrast, INFECTED eczema = eczema complicated by secondary bacterial/viral infection
- Erythema
- Exudation - may be profuse —> greasy/moist scale, surface beneath raw and red
- Crusting
- Sharp margin
- Encircling collarette
- Small pustules in the advancing edge
- Deep persistent fissuring to flexures if involved
HISTO = subacute/chronic eczema Spongiosis Acanthosis Hyperkeratosis Patchy Parakeratosis Dermal polymorphonuclear + lymphocytic infiltrate —> exocytosis Subcorneal pustulation
MX Treat primary cause i.e. ulcer Modify footwear if relevant Mild cases - topical ABs Severe cases - oral ABs Acute exudative lesions - dilute condys soaks + oral ABs
Infective eczema/dermatitis of children assoc with HTLV-1 (human T-cell leukaemia virus)
Severe exudative eczema with crusting
- scalp
- eyelid margims
- perinasal skin
- retroaurocular areas
- Axillae
- Groin
Generalised fine papular rash
Chronic nasal discharge
Positive staph/beta haemolytic strep from nose/skin
Responded to PO ABs —> relapsed on cessation
Risk of developing -
- T-cell leukaemia in adulthood
- Tropical spastic paraparesis
Post-traumatic eczema
Koebner phenomenon —> rare for eczemas
No past hx eczema
Eczema developing at sites of trauma, burn scars
Saphenous vein graft donor sites for CABG surgery
- Reddish brown
- Slightly crusted, scaly
- Occasional papulovesicles
- sensory neuropathy
Histo - subacute spongiotic dermatitis
Responds to TCS, relapse upon cessation
Chronic superficial scaly dermatitis
@
Small plaque parapsoriasis
Digitate dermatosis
Bening form of parapsoriasis en plaques
CLINICAL FEATURES Chronic Regular oval round to finger-like erythematous, pink, brown, slightly yellow, slightly wrinkled (like cigarrete paper), slightly scaly patches Little or no irritation Though some itching possible Limbs, trunk Seldom involves face, palms, soles Does not become malignant Onset middle age Rare in darker skin type Aetiology unknown
Prelymphomatous eruption vs chronic superficial scaly dermatitis
N.B some cases originally dx as chronic superficial scaly dermatitis later develop reticulate pigmentation or atrophy —> re-classifed as prelymphomatous poikiloderma
PRELYMPHOMATOUS ERUPTION Bizarre or angulated shape Fine scale (chronic superficial ssalyndermatitis has coarser scale) May be irritable Progresses to cutaneous lymphoma
COURSE/PROGNOSIS
More prominent in winter than summer
May clear temporarily with natural sunlight/phototherapy
May clear with topical Rx but recurs in the same/adjacent areas when Rx stopped
Stabilise —> persist throughout life
In some —> clears permanently
DDX Nummular dermatitis Eczematides Poikiloderma MF
MX = symptomatic Rx Emollient Mild TCS ointment Heliotherapy Phototherapy - UVB, PUVA —> remission, but relapses
HISTO not characteristic
Mild eczematous changes - patchy parakeratosis, mild spongiosis
Little/no dermal infiltrate - mainly perivascular lymphocytes
Dermatophytide
Reaction at a remote site to a dermatophyte infection
Secondary distant aseptic skin lesion
Should be suspected when the presence of a dermatophyte infection has been established and no fungus demomstrated in the dermatophytide lesions
Clearing of dermatophytide after dermatophyte eradicated
More likely with inflammatory dermatophytes i.e. T. Mentagrophytes
CLINICAL PATTERNS
Hands Eczematous vesicles symmetrically on sides of fingers —> usually reaction to tinea pedis
Mimic pityriasis rosea
Erysipelas-like dermatitis
Erythema nodosum
EAC
Urticaria
Erythroderma
