Irritant dermatitides

AKA sweaty sock syndromeLocation

Plantar surfaces of feet and big toes, palmsTiming

Toddlers and school-ageFall or winterResolution by adolescence

DescriptionChronic, red, scaly patches with fissuring

Juvenile Plantar-Palmar Dermatosis

Due to wetting of skin during day followed by drying at night

TreatmentShoes that breatheCharcoal insolesLubrication of feet at nightTopical steroids in severe cases

Juvenile Plantar-Palmar Dermatosis

Irritant dermatitides

Lip-licking eczema Thumb sucking eczema

Other rashes

Benign self-limited disorderTiming

Most common adolescents and young adultsProdrome of malaise, h/a

DescriptionHerald patch

Pink, slightly scalyMay clear centrally

Pityriasis rosea

5-10 days laterSmall lesions: trunk, proximal extremeties

Inverse pityriasisLesions predominate on face and distal ext

(palms/soles)Description

Small, round papulesEnlarge to 2mm ovalsScaly surfaceRaised, but can be macularErythematous, hyper or hypopigmentedMay create “christmas tree” pattern over thorax

Pityriasis rosea

CoursePeaks in several weeksDuration 2-3 mos

TreatmentNo treatment requiredOral erythromycin and

UV light may hasten resolution

Etiology unknown?infectious?

Pityriasis rosea

Extend beyond margin of the woundMost common in BlacksTreatment

Intralesional steroidsCombination with surgical excisionOften recur

Keloids

Unclear etiology… no treatment required

Annular eruption Begins as papule that

gradually extends peripherally to form a ringRaised, induratedOverlying epidermis intactSame color as adjacent

skinExtensor surfaces

Resolves over months

Granuloma Annulare

Contact Dermatitis

Irritant contact dermCaustic agents (non-allergic)Allergic contact derm

T-cell mediated (type 4- delayed)Poison Ivy or NickelInitial rxn needs 7-14 day sensitization period

Reexposure provokes rapid rxn (hours)

Categories

DescriptionLinear streakserythematous papules and

vesciclesLarge patches (heavy exposure)Impressive swelling (face,

digits, genitalia)Contact

Sap of plants, objects, smokeWash skin immediatelyCan not spread after 20min

Rhus Dermatitis (Poison Ivy)

Photocontact (Phototoxic)True cell-mediated delayed hypersensitivitySun exposure precipitates urticarial eruptionMarked by sun exposed areas onlyPrecipitated by

TetracyclineSulfaThiazidesNSAIDSFluoroquinolonesGriseofulvinTopical agents

Photocontact and Phototoxic Reactions

Agents applied to skin:Non-immunologic exaggerated sunburn rxnPhotodermatitis most common

Plant-derived photosensitizers:Psoralens (lemons, limes, figs, dill, parsley,

parsnips, carrots, celery)Macules: Bullae: Hyperpigmented patchMay have bizarre patterns mimicing abuse

Phototoxins

Phototoxic Rxn (Psoralens)

LemonsLimesFigsDillParsleyParsnipsCarrotsCelery

Localized: topical steroidsSevere or Widespread: systemic steroids

1mg/kg/day tapered over 2wksIdentification of trigger and avoidance are

key!!

Treatment of Contact Derm

Fungal infections

Aka autoeczematizationWidespread secondary eczematous dermatitis

Contact dermTinea (particularly at start of therapy)

Id Reaction

DermatophytesTinea (ringworm fungi)

YeastsCandida

Diaper dermatitisPityrosporum

Tinea versicolorBoth have been implicated in seborrhea

Classification

DescriptionPruritic, annular lesion with central clearingBorder: microvesicles rupture then scale

AcquisitionDirect contact with infected kittens

Trichophyton tonsurans

CourseMay expand up to 5cm over several weeks

Tinea corporis

DiagnosisConfirmed by KOH

Loose scales at marginLong, branching, septate rods of uniform width

that cross borders of epidermal cells

TreatmentGlabrous skin areas: topical antifungalsMultiple or widespread: oral griseofulvin

Tinea Corporis

Aka: Athlete’s footLocation:

Web spaces b/w toesSides of toesMay involve the plantar or dorsal surfaces

Timing: Mostly adolescentsAcquisition: contaminated showers, etc

Warm, moist environmentsDescription:

Scaling and fissuringVesiculopustular lesions and maceration Intense burning or itching

Tinea Pedis

Dx:Clinical groundsConfirmed by KOH

Tx:Antifungal creams or

powdersReducing foot moistureOral antifungals if

severe

Tinea Pedis