A U d t EA U d t EAn Update on Eczema An Update on Eczema & Common Skin Infections& Common Skin Infections& Common Skin Infections & Common Skin Infections

in Childrenin Children

Nelly Rubeiz, MDNelly Rubeiz, MDD f D lD f D lDept. of DermatologyDept. of Dermatology

American University of BeirutAmerican University of Beirutyy

Atopic dermatitisAtopic dermatitisAtopic dermatitis Atopic dermatitis

U ll t t i l i fU ll t t i l i fUsually starts in early infancy Usually starts in early infancy

Xerosis (dry skin) Xerosis (dry skin) Pruritus Pruritus Eczematous lesionsEczematous lesions

PathophysiologyPathophysiologyPathophysiologyPathophysiology

Genetic predispositionGenetic predispositionXerosisXerosis -- defective lipid barrierdefective lipid barrierXerosis Xerosis defective lipid barrierdefective lipid barrierImmune defect Immune defect

AtopyAtopyAtopyAtopy

Skin barrierSkin barrierSkin barrierSkin barrier

The itch scratch cycleThe itch scratch cycleThe itch scratch cycleThe itch scratch cycle

Atopic dermatitisAtopic dermatitisAtopic dermatitisAtopic dermatitis

“Th it h th t h ”“The itch that rashes”

Very commonVery commonVery commonVery common

At i d titi ff tAt i d titi ff t 1515 2525% f hild% f hildAtopic dermatitis affects Atopic dermatitis affects 1515--2525% of children% of childrenAdults: Adults: 00..99%%

Increased incidence in urban populationsIncreased incidence in urban populationsp pp p

AgeAgeAgeAge

Most prevalent in infancy & childhoodMost prevalent in infancy & childhoodInIn 8585% of cases: in the% of cases: in the 11stst year of lifeyear of lifeIn In 8585% of cases: in the % of cases: in the 11 year of lifeyear of life9595% of cases: before % of cases: before 5 5 yearsyears

Infantile EczemaInfantile Eczema

After After 66--8 8 weeks of lifeweeks of lifeDry skin Dry skin -- usually spares the diaper area usually spares the diaper area yy y p py p pFace, scalp, chest, and extensor extremities Face, scalp, chest, and extensor extremities Erythematous exudative patchesErythematous exudative patchesErythematous exudative patches Erythematous exudative patches Child often very irritable and sleeps poorly Child often very irritable and sleeps poorly because of itchingbecause of itchingbecause of itching because of itching

ChildhoodChildhood

Ski i d d hSkin is dry and rough Pallor of the face Dennie-Morgan folds Flexures (antecubital and poplitealFlexures (antecubital and popliteal fossae), neck, back, ankles & wristseck, back, ankles & wrists

/ h fPruritus / Lichenification Excoriations and crusting are commong

AdulthoodAdulthoodAdulthoodAdulthood

Lesions become more diffuseLesions become more diffuseThe face is commonly involvedThe face is commonly involvedXerosis is prominentXerosis is prominentXerosis is prominentXerosis is prominentLichenificationLichenification

AdultsAdultsAdultsAdults

DiagnosisDiagnosis

PruritusPruritusPruritus Pruritus Distribution Distribution Chronic recurring course Chronic recurring course Strong family history of atopyStrong family history of atopyStrong family history of atopyStrong family history of atopy

Differential DiagnosisDifferential DiagnosisDifferential DiagnosisDifferential Diagnosis

Contact DermatitisNummular DermatitisNummular DermatitisPsoriasisScabiesSeborrheic DermatitisSeborrheic DermatitisTinea Corporis

Disease courseDisease courseDisease course Disease course

Tendency for sensitive skin may remain Tendency for sensitive skin may remain Most cases eczema gradually improvesMost cases eczema gradually improvesMost cases, eczema gradually improvesMost cases, eczema gradually improves~~22//3 3 of children “outgrow” their eczemaof children “outgrow” their eczemaFew continue to have eczema Few continue to have eczema

Kissling S. Hautarzt 1994;45:368-71.

AssociationsAssociationsAssociationsAssociations

3030% d l th% d l th3030% develop asthma % develop asthma 3535% have nasal allergies % have nasal allergies

Urticaria and anaphylactic reactions to food Urticaria and anaphylactic reactions to food occur with increased frequencyoccur with increased frequencyoccur with increased frequency occur with increased frequency

peanuts, eggs, milk, soya, fish, and seafood. peanuts, eggs, milk, soya, fish, and seafood.

Associated Conditions

EczemaEczema -- impetigoimpetigoEczema Eczema impetigoimpetigo

Herpes simplexHerpes simplexHerpes simplexHerpes simplex

Molluscum contagiosumMolluscum contagiosumMolluscum contagiosumMolluscum contagiosum

WartsWartsWartsWarts

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Triggers of EczemaTriggers of EczemaTobacco smokeTobacco smokeExcessive temperatures (hot or cold)Ha sh chemicals s ch as sol ents dete gentsHarsh chemicals such as solvents, detergents..Skin care products: alcohol, soaps..Irritating fibers such as wool and syntheticsCosmetics and perfumesEmotional stressFood allergens (milk fish eggs peanuts )Food allergens (milk, fish, eggs, peanuts..)Other allergens (pollen, pets, dust mites)SweatSweat

TreatmentTreatmentHydrationHydration -- EmollientsEmollientsHydration Hydration Emollients Emollients Avoid irritants / allergensAvoid irritants / allergensTopical steroidsTopical steroidsTopical steroidsTopical steroidsTopical immunomodulatorsTopical immunomodulatorsS i hS i hSystemic therapy Systemic therapy

Systemic antibiotics Systemic antibiotics Antihistamines Antihistamines Systemic steroids: rarely usedSystemic steroids: rarely usedy yy y

Topical immunomodulatorsTopical immunomodulatorsTopical immunomodulatorsTopical immunomodulators

Tacrolimus Pimecrolimus

Pimecrolimus (Elidel®)Pimecrolimus (Elidel®)Pimecrolimus (Elidel®) Pimecrolimus (Elidel®) Topical steroidTopical steroid--free medication withfree medication withTopical steroidTopical steroid free medication with free medication with immuneimmune--modulating and antimodulating and anti--inflammatory inflammatory propertiespropertiespropertiespropertiesInhibits calcineurin Inhibits calcineurin S l ti l bl k TS l ti l bl k T ll & t llll & t llSelectively blocks TSelectively blocks T--cell & mast cell cell & mast cell inflammatory cytokine production inflammatory cytokine production

Pimecrolimus (Elidel®)Pimecrolimus (Elidel®)Pimecrolimus (Elidel®) Pimecrolimus (Elidel®)

Available as a Available as a 11% cream% creamProvides a steroidProvides a steroid--free alternativefree alternativeProvides a steroidProvides a steroid free alternative free alternative It relieves the itch and inflammation It relieves the itch and inflammation

d b t i d titid b t i d titicaused by atopic dermatitiscaused by atopic dermatitis

Pimecrolimus (Elidel®)Pimecrolimus (Elidel®)

A d fA d f

Pimecrolimus (Elidel®) Pimecrolimus (Elidel®)

Approved for Approved for shortshort--term term intermittent longintermittent long--term treatmentterm treatmentpatients overpatients over 33 months of agemonths of agepatients over patients over 3 3 months of agemonths of ageIn some countries, it is only approved for In some countries, it is only approved for children overchildren over 22 yrsyrschildren over children over 2 2 yrs yrs

How to use PimecrolimusHow to use PimecrolimusHow to use PimecrolimusHow to use Pimecrolimus

Aff t d ( ) t i d ilAffected area(s) twice dailyDo not use occlusive dressings Mi i iMinimize sun exposure Stop use once signs or symptoms resolveU lli t i t thUse an emollient as maintenance therapy

How to use PimecrolimusHow to use Pimecrolimus

R t t t t t t fi t i fR t t t t t t fi t i f

How to use PimecrolimusHow to use Pimecrolimus

Restart treatment at first sign of recurrence Restart treatment at first sign of recurrence →→→→itchitchIf diti d t i ithiIf diti d t i ithi 66If condition does not improve within If condition does not improve within 6 6 weeks of treatment or if it worsens, stop weeks of treatment or if it worsens, stop applying pimecrolimus creamapplying pimecrolimus creamapplying pimecrolimus cream applying pimecrolimus cream May need a short course of topical steroid May need a short course of topical steroid to control a flare of eczemato control a flare of eczemato control a flare of eczemato control a flare of eczema

Pharmacokinetics studiesPharmacokinetics studiesPharmacokinetics studiesPharmacokinetics studies

Adults & children with extensive ADAdults & children with extensive ADNegligible absorption of pimecrolimusNegligible absorption of pimecrolimusNegligible absorption of pimecrolimus Negligible absorption of pimecrolimus through the skinthrough the skinG tlG tl ↓↓ lik lih d f t i ff tlik lih d f t i ff tGreatly Greatly ↓↓ likelihood of systemic effects likelihood of systemic effects after topical applicationafter topical application

Pimecrolimus side effectsPimecrolimus side effectsPimecrolimus side effectsPimecrolimus side effects

The most common side effect at the The most common side effect at the site of application site of application pppp

Sensation of Sensation of warmth or burningwarmth or burningMild to moderate in severityMild to moderate in severityMild to moderate in severityMild to moderate in severityClears within a few days Clears within a few days

Pimecrolimus side effectsPimecrolimus side effectsPimecrolimus side effectsPimecrolimus side effects

slightly increased susceptibility to skin slightly increased susceptibility to skin infections such as infections such as folliculitisfolliculitis, , impetigoimpetigo, , ,, p gp g ,,herpes simplexherpes simplex and and molluscum molluscum contagiosumcontagiosumcontagiosumcontagiosum. .

PimecrolimusPimecrolimus -- precautionsprecautionsPimecrolimus Pimecrolimus precautionsprecautions

Avoid use in areas affected by active, Avoid use in areas affected by active, cutaneous bacterial and viral infectionscutaneous bacterial and viral infections

Wahn, U. et al. Efficacy and Safety of Pimecrolimus Cream in the Long-Term Management of AtopicCream in the Long Term Management of Atopic Dermatitis in Children. Pediatrics 2002;110:e2

Wahn, U. et al. Pediatrics 2002;110:e2

Pimecrolimus groupPimecrolimus groupPimecrolimus groupPimecrolimus group

Significantly fewer AD flaresSignificantly fewer AD flaresRegardless of baseline severityRegardless of baseline severityRegardless of baseline severityRegardless of baseline severityAt At 6 6 months and months and 1 1 year, patients with year, patients with

fl t i hfl t i hno flare twice as muchno flare twice as muchLonger flareLonger flare--free periodfree periodLonger flareLonger flare free periodfree periodLess topical steroid required Less topical steroid required

Wahn, U. et al. Pediatrics 2002;110:e2

Studies to date concerning infants and Studies to date concerning infants and children using the cream for up to a children using the cream for up to a g pg pyear have shown that pimecrolimus year have shown that pimecrolimus appears to beappears to be well tolerated in all agewell tolerated in all ageappears to be appears to be well tolerated in all age well tolerated in all age groups. groups.

However, as this is a new drug, the However, as this is a new drug, the full safety profile of the medication is full safety profile of the medication is y py punknown; the main concerns relate to unknown; the main concerns relate to its effect on the immune systemits effect on the immune systemits effect on the immune system. its effect on the immune system.

TacrolimusTacrolimus -- Protopic®Protopic®Tacrolimus Tacrolimus Protopic®Protopic®

M h i f ti i il t i liM h i f ti i il t i liMechanism of action similar to pimecrolimus Mechanism of action similar to pimecrolimus Children: tacrolimus ointment Children: tacrolimus ointment 00..0303%. %. Ad ltsAd lts 00 11% ointment% ointmentAdults: Adults: 00..11% ointment% ointment

ImpetigoImpetigoImpetigoImpetigo

Superficial skin infectionSuperficial skin infectionStaph or StrepStaph or StrepStaph or StrepStaph or StrepHighly contagiousHighly contagiousChildrenChildren

TreatmentTreatmentTreatmentTreatment

Topical antibiotic: localizedTopical antibiotic: localizedSystemic antibiotic: widespreadSystemic antibiotic: widespreadSystemic antibiotic: widespreadSystemic antibiotic: widespread

LocalizedLocalizedLocalized Localized

Fusidic acid (Fucidin)Fusidic acid (Fucidin)--------resistanceresistanceMupirocin (Bactroban)Mupirocin (Bactroban)

Retapamulin (AltabaxRetapamulin (Altabax®)®)Retapamulin (AltabaxRetapamulin (Altabax®)®)

A new class of antibacterials called A new class of antibacterials called pleuromutilinpleuromutilinppFDAFDA--approved for the treatment of approved for the treatment of impetigo (impetigo (20072007))impetigo (impetigo (20072007))Indicated for use twice daily for Indicated for use twice daily for 5 5 days days in patients > in patients > 9 9 months of age months of age

Topical retapamulin versus oralTopical retapamulin versus oralTopical retapamulin versus oral Topical retapamulin versus oral cephalexin in the treatment of infected cephalexin in the treatment of infected dddermatitis.dermatitis.

J Am Acad Dermatol 2006;55:1003-13.

Topical retapamulin versus topical Topical retapamulin versus topical fusidic acid in impetigo.fusidic acid in impetigo.p gp g

Dermatology 2007;215:331-40.

ExtensiveExtensiveExtensive Extensive

Extensive impetigoExtensive impetigoExtensive impetigoExtensive impetigo

Systemic antibioticsSystemic antibioticsCommunityCommunity--acquired MRSAacquired MRSACommunityCommunity acquired MRSAacquired MRSA

Tinea capitisTinea capitis

KerionKerionKerionKerion

Diagnosis: KOHDiagnosis: KOHDiagnosis: KOH Diagnosis: KOH

DiagnosisDiagnosisDiagnosisDiagnosis

Fungal cultureFungal cultureTrichophytonTrichophytonTrichophytonTrichophytonMicrosporumMicrosporumEpidermophytonEpidermophytonEpidermophytonEpidermophyton

Treatment: Systemic antifungalTreatment: Systemic antifungal

Meta-analysis of 6 studies comparing terbinafine and griseofulvin for the treatment of childhood tinea capitisgriseofulvin for the treatment of childhood tinea capitis

Fleece, D. et al. Pediatrics 2004;114:1312-5.

Microsporum canisMicrosporum canisMicrosporum canisMicrosporum canis

Griseofulvin

Asymptomatic fungal carriage in Asymptomatic fungal carriage in household contacts of patients withhousehold contacts of patients withhousehold contacts of patients with household contacts of patients with

tinea capitistinea capitis

209 209 contacts examinedcontacts examined77 22% clinically evident disease% clinically evident disease77..22% clinically evident disease% clinically evident disease4444..55% silent fungal carriage on scalp% silent fungal carriage on scalpChildren <Children < 1616 more likely carriersmore likely carriersChildren < Children < 16 16 more likely carriersmore likely carriersMales less than femalesMales less than females

Eradicate potential reservoirEradicate potential reservoir

J Eur Acad Dermatol Venereol 2007;21:1061-4.

Pediculosis capitisPediculosis capitis

Head liceHead liceHead liceHead lice

The most common ectoparasites using The most common ectoparasites using h h th h thumans as a host. humans as a host. Control is difficult because lice areControl is difficult because lice areControl is difficult because lice are Control is difficult because lice are becoming resistant to insecticides.becoming resistant to insecticides.

Pediculus humanus capitisPediculus humanus capitisPediculus humanus capitisPediculus humanus capitis

Gray/tan and white Gray/tan and white 33 toto 44 mm in lengthmm in length3 3 to to 4 4 mm in length mm in length Mouth adapted to suck blood and legs Mouth adapted to suck blood and legs d t d t i h id t d t i h iadapted to grip hairs adapted to grip hairs

What do head lice look like?What do head lice look like?

There are three forms of lice: There are three forms of lice: the egg (nit)the egg (nit)the egg (nit)the egg (nit)

the nymphthe nymph

the adultthe adult

Egg/NitEgg/Nit

Very small, hard to seeVery small, hard to seeOften confused with dandruffOften confused with dandruffOften confused with dandruff Often confused with dandruff Eggs are glued to the hair in egg Eggs are glued to the hair in egg

i ( it ) ith hiti di ( it ) ith hiti dcasings (nits) with chitin and are casings (nits) with chitin and are deposited close to the scalp deposited close to the scalp

Egg/nitEgg/nitEgg/nitEgg/nit

Nits take ~ Nits take ~ 8 8 days to hatch days to hatch Eggs likely to hatch are usually locatedEggs likely to hatch are usually locatedEggs likely to hatch are usually located Eggs likely to hatch are usually located within within 1 1 cm of the scalpcm of the scalpN l l id i bl i t tN l l id i bl i t tNewly laid or viable intact eggs are Newly laid or viable intact eggs are opalescent, whereas eggs that have opalescent, whereas eggs that have hatched are whitehatched are white

NitsNitsNitsNits

NitNitNitNit

NymphNymph

The nit hatches into a baby louse The nit hatches into a baby louse called a nymph.called a nymph.y py pNymphs mature into adults ~ Nymphs mature into adults ~ 8 8 days days after hatchingafter hatchingafter hatching. after hatching. To live, the nymph must feed on To live, the nymph must feed on blood.blood.

The adult louseThe adult louse

The adult female lays her eggs (The adult female lays her eggs (77--10 10 d ) th b f h i h ftd ) th b f h i h ftper day) near the base of hair shaftper day) near the base of hair shaft

Adult lice can live up to Adult lice can live up to 30 30 days on a days on a du t ce ca e up todu t ce ca e up to 3030 days o adays o aperson's headperson's headTo live adult lice feed on bloodTo live adult lice feed on bloodTo live, adult lice feed on bloodTo live, adult lice feed on bloodLice can crawl and climb but cannot Lice can crawl and climb but cannot jump or fly!jump or fly!

Adult lice can survive for Adult lice can survive for 2 2 days away days away from the scalpfrom the scalppp

Nit th th h d iNit th th h d iNits, on the other hand, can survive Nits, on the other hand, can survive for up to for up to 10 10 days away from the days away from the human hosthuman host

Clinical ManifestationsClinical Manifestations

AsymptomaticAsymptomaticPruritus is the most common symptomPruritus is the most common symptomPruritus is the most common symptom Pruritus is the most common symptom Excoriations and secondary bacterial Excoriations and secondary bacterial i f tii f tiinfection infection Occipital and posterior cervicalOccipital and posterior cervicalOccipital and posterior cervical Occipital and posterior cervical lymphadenopathy are commonlymphadenopathy are common

Pyoderma due to licePyoderma due to licePyoderma due to licePyoderma due to lice

TreatmentTreatmentTreatmentTreatment

Pediculicides are the most effective Pediculicides are the most effective treatment for pediculosis capitis treatment for pediculosis capitis p pp pMany pediculicides are availableMany pediculicides are availableP di li id ith l id l ff tP di li id ith l id l ff tPediculicides with long residual effect Pediculicides with long residual effect are more likely to be ovicidalare more likely to be ovicidal

The pediculicide should be applied toThe pediculicide should be applied toThe pediculicide should be applied to The pediculicide should be applied to the entire scalpthe entire scalpTh f h i diti h ld bTh f h i diti h ld bThe use of hair conditioners should be The use of hair conditioners should be avoided before application of a avoided before application of a pediculicide because they coat the hair pediculicide because they coat the hair and protect the lice and nitsand protect the lice and nitsand protect the lice and nitsand protect the lice and nits

Permethrin Permethrin 11%%PyrethrinPyrethrinPyrethrinPyrethrinGamma benzene hexachloride Gamma benzene hexachloride 11%%Malathion Malathion 00..55%%Trimethoprim/sulfamethoxazoleTrimethoprim/sulfamethoxazoleTrimethoprim/sulfamethoxazoleTrimethoprim/sulfamethoxazoleIvermectin*Ivermectin*200 200 µg/kg (>µg/kg (>55yrs)yrs)

PermethrinPermethrin

Th t t t f h i b f ffiTh t t t f h i b f ffiThe treatment of choice because of efficacy The treatment of choice because of efficacy and lack of toxicity and lack of toxicity 11% permethrin is applied for% permethrin is applied for 1010 minutesminutes11% permethrin is applied for % permethrin is applied for 10 10 minutes minutes and then rinsed offand then rinsed offPermethrin is both pediculicidal and ovicidal.Permethrin is both pediculicidal and ovicidal.Permethrin is both pediculicidal and ovicidal. Permethrin is both pediculicidal and ovicidal. It leaves a residue on the hair and remains It leaves a residue on the hair and remains active for active for 2 2 weeks after application weeks after application ppppA second treatment A second treatment 7 7 to to 10 10 days later to days later to ensure cureensure cure

Gamma benzene hexachlorideGamma benzene hexachloride

The The 11% shampoo is applied to dry hair and % shampoo is applied to dry hair and l ft fl ft f 1010 i ti tleft on for left on for 10 10 minutes minutes Because of its low ovicidal activity, repeated Because of its low ovicidal activity, repeated

li tili ti 77 tt 1010 d l td l tapplication application 7 7 to to 10 10 days later days later Potential for neurotoxicity and bone marrow Potential for neurotoxicity and bone marrow

iisuppression suppression

Trimethoprim/sulfamethoxazoleTrimethoprim/sulfamethoxazoleTrimethoprim/sulfamethoxazoleTrimethoprim/sulfamethoxazole

TrimethoprimTrimethoprim 1010 mg/kg/day andmg/kg/day andTrimethoprim Trimethoprim 10 10 mg/kg/day and mg/kg/day and sulfamethoxazole, sulfamethoxazole, 50 50 mg/kg/day in two mg/kg/day in two divided doses) fordivided doses) for 1010 days +/days +/-- shampooshampoodivided doses) for divided doses) for 10 10 days +/days +/-- shampooshampooDestroys the gut flora of the louse, thereby Destroys the gut flora of the louse, thereby i t f i ith it bilit t th ii t f i ith it bilit t th iinterfering with its ability to synthesize interfering with its ability to synthesize vitamin B vitamin B Death ensues from vitamin B deficiencyDeath ensues from vitamin B deficiencyFor cases not responsive to traditional For cases not responsive to traditional pppediculicides or suspected cases of licepediculicides or suspected cases of lice--related resistance to therapy related resistance to therapy pypy

Hair DryersHair DryersHair DryersHair Dryers

169 169 children aged children aged 6 6 yearsyearsHead liceHead liceHead liceHead liceTreated for about Treated for about 30 30 minmin

Goates, et al. Pediatrics 2006;118:1962-70.

Hair DryersHair DryersHair DryersHair Dryers

Goates, et al. Pediatrics 2006;118:1962-70.

Further research may be needed to Further research may be needed to determine the optimal way to use determine the optimal way to use p yp ydomestic hairdryers and their domestic hairdryers and their effectivenesseffectivenesseffectiveness. effectiveness.

Nit removalNit removalNit removalNit removal

Combing Combing Soak the hair with white vinegar (Soak the hair with white vinegar (33--55% % g (g (acetic acid) or acetic acid) or 88% formic acid rinses to % formic acid rinses to soften the cement of nits before combing soften the cement of nits before combing ggthe hair. the hair. Mechanical nit and louse removalMechanical nit and louse removalMechanical nit and louse removal Mechanical nit and louse removal

Environmental measuresEnvironmental measures

Household members and close contacts Household members and close contacts should be examined & treated if infestedshould be examined & treated if infestedTreat bedmates prophylacticallyTreat bedmates prophylacticallyM hi h ll l thi d b d liM hi h ll l thi d b d liMachine wash all clothing and bed linens. Machine wash all clothing and bed linens. Use the hot water (Use the hot water (130130°°F) cycle. Dry F) cycle. Dry laundry at high heat for at least laundry at high heat for at least 20 20 minutes.minutes.minutes. minutes.

Environmental measuresEnvironmental measuresEnvironmental measuresEnvironmental measures

Store all clothing stuffed animalsStore all clothing stuffed animalsStore all clothing, stuffed animals,... Store all clothing, stuffed animals,... that cannot be washed or dry cleaned that cannot be washed or dry cleaned into a plastic bag and seal fointo a plastic bag and seal fo 22 eekseeksinto a plastic bag and seal for into a plastic bag and seal for 2 2 weeksweeksSoak combs and brushes for Soak combs and brushes for 1 1 hour in hour in alcohol, Lysol , or wash with soap and alcohol, Lysol , or wash with soap and hot (hot (130130°°F) waterF) waterhot (hot (130130 F) water F) water Vacuum the floor and furnitureVacuum the floor and furniture

Treatment failuresTreatment failuresTreatment failuresTreatment failures

NoncomplianceNoncomplianceImproper application of pediculicidesImproper application of pediculicidesImproper application of pediculicidesImproper application of pediculicidesReinfestationReinfestationResistance to pediculicidesResistance to pediculicides