Contact dermatitis
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Contact dermatitis Presentation Transcript

  • 1. CONTACT DERMATITIS Martín Gracia Facultad de Medicina Universidad Nacional de Colombia. Dermatología.
  • 2. DEFINICIÓN
    • Alteración inflamatoria
      • frecuente
      • Exposición a varios antígenos e irritantes
    • Mecanismos  distintos tipos
      • Eczema de contacto o dermatitis de contacto alérgica (reacción de hipersensibilidad de tipo IV)
      • Dermatitis de contacto irritativa (de causa no alérgica)
      • Fotodermatitis de contacto (reacción de tipo IV)
      • Urticaria de contacto (reacción de hipersensibilidad de tipo I)
  • 3. DEFINICIÓN
    • Presentación clínica
      • Vesículas y bullas localizadas sobre una piel eritematosa  estadios agudos
      • Placas eritematosas liquenificadas  estadios crónicos
    • Diagnóstico
      • Localización – erupción
      • Historia – exposición
      • Pruebas epicutáneas - aplicación alergeno producirá inflamación
  • 4. DEFINICIÓN
    • Tratamiento
        • eliminación – agente
        • uso de cremas esteroides antiinflamatorias
        • antihistamínicos
      • casos graves
        • corticosteroides orales
  • 5. Eczema de contacto o dermatitis de contacto alérgica
    • Eritema
  • 6. Eczema de contacto o dermatitis de contacto alérgica; fotodermatitis de contacto
    • Eritema, excoriación, descamación, liquenificación y edema
  • 7. Eczema de contacto o dermatitis de contacto alérgica
    • Eritema, excoriación, liquenificación y costras
  • 8. Eczema de contacto o dermatitis de contacto alérgica
    • Eritema, fisuras y descamación
  • 9. Eczema de contacto o dermatitis de contacto alérgica
    • Eritema y costras
  • 10. fotodermatitis de contacto (reacción de tipo IV)
    • Eritema, hinchazón y vesículas
  • 11. Dermatitis de contacto irritativa (de causa no alérgica)
    • Eritema, edema, ampollas
  • 12. Dermatitis de contacto irritativa (de causa no alérgica)
    • Eritema, edema, ampollas, vesiculas, hinchazón
  • 13. Dermatitis de contacto irritativa (de causa no alérgica)
    • Descamación, erosiones, escoriaciones, costras
  • 14. Dermatitis de contacto irritativa (de causa no alérgica)
    • Eritema, vesiculas, descamación y edema
  • 15. Epidemiology
    • the most common occupational disease in the United States
    • 90%  skin disorders  workplace
    • 6 million chemicals
      • 3000 have been known to cause allergic contact dermatitis (ACD)
      • New chemical sensitizers are introduced
      • annual cost  $250 million
        • Lost productivity
        • medical care
        • disability payments
  • 16. Epidemiology
    • Allergic contact dermatitis (ACD) does occur in children and infants
  • 17. Allergic versus irritant contact dermatitis
    • Distinguishing  allergic and irritant triggers
      • Clinical and histologic examination
  • 18. Allergic versus irritant contact dermatitis
    • Both forms of contact dermatitis involve an inflammatory pathway
      • The reactions of ICD are nonimmunologic
        • Direct epidermal keratinocyte damage
        • concentration  irritant  duration contact
      • ACD
        • Affects genetically susceptible persons
          • Previously sensitized by allergen
  • 19. Allergic versus irritant contact dermatitis
    • FR
    • Physical conditions
      • Heat
      • Cold
      • repeated frictional exposure
      • Low humidity
    • Prior damage – skin
      • Dehydration
      • Trauma
      • Compromises – integrity - epidermal barrier (stratum corneum)
    • *more vulnerable to irritants
  • 20. Allergic versus irritant contact dermatitis
    • Atopic persons
      • Greater susceptibility ICD
        • phenomenon caused by ‘‘itch - scratch cycle’’ of AC
          • increased penetration of irritants  no allergens
          • Tendency in atopy to favor pathways of the Th2  rather than the Th1 pathways of ACD
  • 21. Dermatitis de contacto alérgica
    • Sensitization (afferent phase)
    • Most allergic diseases  immediate hypersensitivity response involving IgE
    • ACD  prototypic delayed (or cell-mediated) hypersensitivity reaction
    • Previously sensitized T-helper cells
  • 22. Dermatitis de contacto alérgica
    • Haptens
    • Contact allergens  Covalently bond with tissue proteins  immunogenic  initiate afferent phase
    • Degree of Th1 sensitization  proportional to stability  hapten-protein couplings
    • > chemically reactive haptens
      • lipid-soluble
      • low-molecular-weight molecules
        • easily penetrate the stratum corneum
        • strongly bind carrier proteins
  • 23. Dermatitis de contacto alérgica
    • Haptens
    • Within the epidermis
      • Pinocytosis by Langerhans cells
        • Degradation of the allergens
          • Processed peptides
            • Displayed - Langerhans cell surface  context - major histocompatibility complex class II molecules
  • 24. Dermatitis de contacto alérgica
    • Langerhans cells
      • migrate  regional draining lymph nodes
        • processed peptides are presented to naïve Th1 cells
  • 25. Dermatitis de contacto alérgica
    • New peptides
    • Specific T-cell receptor
    • major histocompatibility complex II molecules
      • ” found only on the Th1 cells of susceptible patients”
    • *Those who have  necessary repertoire  receptor variable regions  genetically rearranged TR-cell
  • 26. Dermatitis de contacto alérgica
    • Successful allergen presentation
      • Langerhans cells  interleukin-1
      • Th1 cells  interleukin -2
        • Clonal proliferation  newly sensitized Th1 cells
          • paracortical region of the lymph nodes
  • 27. Dermatitis de contacto alérgica
    • Patient’s initial contact
      • Number of responding Th1 cells is insufficient to a clinically response
      • But - Then - memory Th1 cells are released into the circulation
  • 28. Dermatitis de contacto alérgica
    • Elicitation (efferent phase)
    • Specific memory Th1 cells – circulating
    • Langerhans cells  Allergen presentation  expanded pool of Th1 cells  occurs in:
      • Epidermis
      • Dermis
      • Regional draining lymph nodes
        • *Skin-specific homing receptors on the Th1 cells
  • 29. Dermatitis de contacto alérgica
    • Th1 cells
      • release inflammatory cytokines
      • interferon-γ  chemotactic
        • macrophages
        • cytotoxic T cells
        • Natural killer cells
      • Granulocyte-macrophage colony–stimulating factor
        • augments  bone marrow’s production
          • Lymphocytes
          • Granulocytes
          • Monocytes
  • 30. Dermatitis de contacto alérgica
    • Culmination
      • epidermal spongiosis (intercellular edema)
      • dermal infiltrate
        • *characteristic of ACD  Lymphocytic
  • 31. Dermatitis de contacto alérgica
    • Latency period
      • From allergen contact to clinical dermatitis
        • time for Langerhans cells to present the allergen
        • time for Th1 cells to
          • proliferate
          • secrete cytokines
          • Travel - site of contact
            • Between 12 to 48 hours - previously sensitized person
  • 32. Clinical features
    • History
    • Detailed
    • Hidden sources of contact allergens
    • Occupational exposure - highest risk 
      • food production
      • construction
      • printing
      • metal plating (enchapado en metal)
      • Machine tool operation (operarios de maquinas)
      • engine service (Mechanics)
      • leather work (trabajo del cuero)
      • health care
      • cosmetology
      • forestry
  • 33. Clinical features
    • Temporal relationship - days off and return to work
      • recent exposures
        • Strong allergens  poison ivy
          • Effect - hours – days
          • after - one exposure
      • long-term exposures > ƒ OACD
        • Weak sensitizers  chromate
          • require repeated exposures - months to years to develop sensitivity
  • 34. Clinical features
    • Exposures ≠ workplace
      • Jewelry
      • Clothing
      • Cosmetics
      • Fragrances
      • Soaps
      • Detergents
      • household cleaning agents
      • paints
      • resins
      • rubbers (caucho y gomas)
      • latex
      • adhesives
      • topical medicines
  • 35. Clinical features
    • One uniformly present feature of ACD is
    • PRURITUS
    • without which the Dx of ACD is excluded
  • 36. Physical examination
    • Appearance - lesion in ACD
      • corresponds - stage at which the patient presents.
  • 37. Physical examination
    • Acute stage
      • Marked erythema
      • Edema
      • Vesicle formation
      • Edema predominates if areas of loose(sueltas) tissue
        • Eyelids
        • Genitalia
  • 38. Physical examination
      • Vesicles
        • Multiple
        • Severe
        • may coalesce into bullae
        • filled with a clear, transudative fluid
        • Rupture during the subacute stage
        • rupture  oozing(resumar) and eroded(erosion)  eczematous appearance
  • 39. Physical examination
      • vesicular fluid
        • does not contain appreciable amounts of the allergen
        • does not spread the eruption to other areas of the body or to other
        • may be replaced by papules
      • Crustin(Costra) and scaling(descamación) soon become more prominent than the erythema and edema
  • 40. Physical examination
      • chronic stage
        • Papulovesicular lesions disappear
        • Lichenification
      • *The principles of prevention and treatment of ACD remain similar, regardless of the stage.
  • 41. Differential diagnosis
      • the physician’s clinical suspicion of ACD may be quite(bastante) high
      • It is paramount(importante)  consider - potentially more serious etiologies
      • ICD > ƒ confused
      • ƒ atopic dermatitis
  • 42. Differential diagnosis
      • Atopic dermatitis
        • onset in infancy
        • ACD is uncommon in children younger than 8 years old
        • Dry skin and pruritus  prominent - before lesions appear - ≠ ACD  afterwards
        • Tends to be symmetrically distributed on extensor surfaces - on flexural surfaces
  • 43. Differential diagnosis
      • Atopic dermatitis
  • 44. Differential diagnosis
      • seborrheic dermatitis
        • predilection for
          • eyebrows
          • nasal labial folds(pliegues naso-labiales)
          • scalp (cuero cabelludo)
        • Mild pruritus
        • Greasy(grasosa) or oily(oleosa) coating(capa) with scaly(descamación)
        • irregularly shaped(forma) erythema
  • 45. Differential diagnosis
      • seborrheic dermatitis
  • 46. Differential diagnosis
      • endogenous dermatoses
        • More intensely pruritic eruptions
        • Nummular dermatitis
          • one or a group of coin – shaped
          • eczematous patches 2 to 10 cm in diameter
            • Usually  torso and extremities  but not the head
        • Dyshidrotic dermatitis
          • appears as multiple vesicles 1 to 2 mm in diameter
            • palms
            • soles
            • lateral aspects of the fingers and toes
  • 47. Differential diagnosis
      • endogenous dermatoses
        • Nummular dermatitis
  • 48. Differential diagnosis
      • endogenous dermatoses
        • Dyshidrotic dermatitis
  • 49. Differential diagnosis
      • Photocontact dermatitis
        • Interaction
          • exogenous chemical  UV component of sunlight
          • recently ingested drug
            • sulfonamide
            • Fluoroquinolone
            • Tetracycline
            • Oral contraceptive
            • nonsteroidal anti-inflammatory drug
            • topically applied substance - cold tar extract (extracto de alquitran frio)
  • 50. Differential diagnosis
      • Photocontact dermatitis
        • Clinically
          • sun-exposed areas
            • face
            • arms
            • upper chest
          • is noticeably spared
            • skin under the chin - behind the ears - upper eyelids
  • 51. Differential diagnosis
    • phototoxic reactions ↔ ICD subset
    • photoallergic reactions ↔ACD subset
  • 52. Differential diagnosis
      • phototoxic reaction
        • Macular
          • tender erythema
        • can resemble(parecer) severe sunburn(quemaduras)
  • 53. Differential diagnosis
      • photoallergic reaction
        • delayed hypersensitivity reaction - induced by UV light  which chemically alters the sensitizing allergen in the skin.
          • Pruritic
          • Papulovesicular
          • Eczematous
            • *similar to ACD
  • 54. Differential diagnosis
      • two types of contact urticaria  subsets of contact dermatitis
  • 55. Differential diagnosis
        • nonallergic form
          • urticaria remains localized  site of contact - caused -direct cell mediator release from:
            • fragrances
            • food preservatives
            • insect stings
            • hairs
            • topical medicines
  • 56. Differential diagnosis
        • Allergic contact urticaria
          • IgE-mediated mast cell stimulation
          • requires prior exposure to sensitizing allergens
          • foods
          • metals
          • animal saliva
          • latex
          • industrial products
          • topical medicines
  • 57. Differential diagnosis
        • Both forms of contact urticaria resemble noncontact urticaria
        • classic wheal and flare response  appears within 30 minutes of exposure
        • allergic contact urticaria may become generalized
          • angioedema or anaphylaxis
        • Urticaria or angioedema - contact or noncontact - can be –mistaken(confundida) for ACD
          • *when the eyelids are involved
  • 58. Differential diagnosis
        • Both forms of contact urticaria resemble noncontact urticaria
        • classic wheal and flare response  appears within 30 minutes of exposure
        • allergic contact urticaria may become generalized
          • angioedema or anaphylaxis
        • Urticaria or angioedema - contact or noncontact - can be –mistaken(confundida) for ACD
          • *when the eyelids are involved
  • 59. Differential diagnosis
    • Skin infections  strongly considered - immunocompromised patients
      • Cellulitis
        • erythema and edema
        • Dx dif
          • warmth
          • tenderness
          • Trauma  common precipitant
          • fever and leukocytosis
  • 60. Differential diagnosis
    • Dermatophytic or tinea
      • Dry
      • scaling erythema
      • annular ring and central clearing
        • Diagnosis  scraping scales  glass slide  adding potassium hydroxide  visualizing branching hyphae
  • 61. Differential diagnosis
    • infections present vesicular lesions
      • herpes simplex virus
        • tender
        • may umbilicate
        • predilection for perioral and genital regions
  • 62. Differential diagnosis
    • varicella zoster virus
        • primary varicella
          • 2- to 3-day prodrome of flu like symptoms
          • erythematous maculopapules
          • diffuse, pruritic vesicles
  • 63. Differential diagnosis
    • varicella reactivated
        • few constitutional symptoms
        • localized pain and paresthesias 2 to 3 days before the eruption
        • grouped vesicles in a dermatomal distribution
  • 64. Differential diagnosis
    • Impetigo
      • all age groups, but is usually seen in young children
      • Streptococcus pyogenes or Staphylococcus aureus
      • involves the face
      • has regional lymphadenopathy
      • self-limited to 2 to 3 weeks
      • vesicles may progress to pustules  easily rupture  honey - colored crust
  • 65. Differential diagnosis
    • Impetigo
  • 66. Differential diagnosis
    • psoriasis
      • thick(espeso) silver - scaled plaques
      • over bright erythema
      • extensor surfaces
    • mycosis fungoides (Primary cutaneous T-cell lymphoma)
      • asymmetric
      • finely scaled(descamadas) plaques on the trunk and groin(ingle)
  • 67. Differential diagnosis
    • psoriasis
      • thick(espeso) silver - scaled plaques
      • over bright erythema
      • extensor surfaces
    • mycosis fungoides (Primary cutaneous T-cell lymphoma)
      • asymmetric
      • finely scaled(descamadas) plaques on the trunk and groin(ingle)
  • 68. Differential diagnosis
    • *biopsy
      • low utility in ACD
        • histologic finding of spongiosis is not specific among eczematous dermatoses
  • 69. Anatomic approach
    • Exposure to the suspect allergen - congruent - distribution of the eruption
    • more exposed areas
      • the hands
      • face
        • > ƒ presenting ACD
  • 70. Anatomic approach
    • Head and neck
    • Scalp have greater resistance than  face, ears, and neck
      • Hair dyes(tintes)
      • Shampoos
        • often spare the scalp but involve its nearby landmarks
    • eyelids and cheeks(mejillas)
      • facial cosmetics
      • products applied to the hands  nail polish(esmalte)
  • 71. Anatomic approach
    • Head and neck
    • common triggers
      • Metals from jewelry piercings - face and ears
      • Topical antibiotics
        • Eyes
        • Ears
  • 72. Anatomic approach
    • Neck
      • cosmetics and fragrances
      • metals
      • exotic woods from necklaces (collares)
      • musical instruments
  • 73. Anatomic approach
    • Extremities
    • 50% involve the hands
      • supposed innocuous items
        • foods
        • moisturizers
        • musical instruments,
        • protective gloves
          • > ƒ fingertips (pulpejos)
  • 74. Anatomic approach
    • Extremities
      • ƒ dorsal side of the hands
        • the skin is thinner
        • density of Langerhans cells is greater than on the palmar side
      • Bracelets, watches, and rings
        • ACD  metal exposure
        • ICD  soap and detergent accumulation under
  • 75. Anatomic approach
    • Extremities
        • photosensitive process
          • hand dermatitis - contiguous with forearms - associated with a facial dermatitis
        • dorsal aspect - feet
          • chrome - tanned leather (cuero)
          • glues (pegamentos)
          • rubber (caucho)
            • components of shoes
  • 76. Anatomic approach
    • Extremities
      • Stasis dermatitis - lower legs - chronic varicose inflammation
        • Significantly increases the risk of ACD from topically applied products
      • Metals – keys - coins -match boxes(encendedores) - pants pockets upper legs
  • 77. Anatomic approach
    • Torso and groin(ingle)
    • Fragrances - deodorants - axillary vault
    • formaldehyde, detergents, and dyes from clothes  torso - axillary folds - sparing vault
    • Rubber chemicals - elastic of under garments (prendas femeninas) - bra line – waistline (cintura)
    • periumbilical region - metallic fasteners(cierrres) – belts(cinturones) – pants
  • 78. Anatomic approach
    • Torso and groin(ingle)
    • Incontinent  bed – bound(obligados) patients - urine - diaper (pañal)
    • ƒ Contraceptive devices  latex-sensitive
    • Medicines, douches, spermicides  genital area - vulva and adjacent thighs(muslos) ≠ vaginal mucosa
  • 79. Anatomic approach
    • Oral mucosa
    • Langerhans cells are sparse(escasas) at mucosal sites
    • contact stomatitis
      • contact gingivitis
      • cheilitis
        • Dental metals - amalgams
          • Nickel
          • Palladium
          • Mercury
          • Gold
  • 80. Anatomic approach
    • Oral mucosa
      • saliva - buffering and diluting effect on the allergen
      • rapid dispersal and absorption of the allergen  extensive vascularity in the mouth
        • low incidence of contact stomatitis
  • 81. Anatomic approach
    • Systemic involvement
    • Systemic ACD - form of autoeczematization - known as an ‘‘id reaction.’’
    • Secondary dermatitis - patients sensitized topically - subsequently re-exposed systemically
      • re-exposure
        • orally
        • intravenously
        • intramuscularly
        • rectally
        • vaginally
        • inhalation
        • after dental
        • surgical devices implanted
  • 82. Anatomic approach
    • Systemic involvement  ‘‘id reaction.’’
    • Generalized eruption - result - hematogenous dissemination - antigen-specific Th1 cells
    • Common contact allergens
  • 83. Allergens
    • Poison ivy
      • specie: Toxicodendron genus
      • plant family: Anacardiaceae
      • the most ubiquitous of four especies
      • family includes
        • poison sumac
        • poison oak
  • 84. Allergens
    • Poison ivy
      • United States - responsible -more cases – ACD
      • Strong sensitizing allergen  urushiol - catechol derivative – sap (savia)
        • sap - difficult to wash off
        • washing - ideally within 10 minutes of exposure
      • dermatitis
        • linear erythema and vesicles
        • vesicular fluid - no allergenic
  • 85. Allergens
    • Poison ivy
      • chronicity and spread(propagación) of symptoms
        • continued unintentional exposure
        • urushiol may persist on clothing, tools, sports equipment, - fur(piel) of pets(animals)
      • Cross-reactions - catechol derivatives- found in other members - Anacardiaceae family
        • Mangoes
        • Cashews
        • Ginkgoes
        • Brazilian peppers(pimienta)
  • 86. Allergens
    • Metals
    • Nickel
      • most common metal allergen
      • prevalence women higher - early sensitization  ear piercings
    • Other
          • Chromium
          • Cobalt
          • Gold
          • organic forms of mercury
  • 87. Allergens
    • Metals
    • Sensitivity to aluminum is quite uncommon
      • substitution with aluminum items - workplace - reduce the incidence
    • metal alloys(aleación) - medical devices – implants
        • stainless steel  contains - nickel and chromium
          • may present - persistent - localized or generalized eczema - loosening - implant
        • Patch testing - metals - low specificity - moderate sensitivity  work-up - metal implant
  • 88. Allergens
    • Medications
    • Topical antibiotics
      • > ƒ neomycin and bacitracin
      • *mupirocin may to be a safe alternative
    • Topical anesthetics
      • ester class
        • benzocaine and tetracaine  ƒ
          • lidocaine, dibucaine, and mepivacaine, are rare sensitizers
  • 89. Allergens
    • Medications
    • Topical corticosteroids
      • structure may be altered to induce allergenicity
        • metabolism in the skin
        • degradative reactions within the pharmaceutical preparation
    • topical antihistamines
      • known to act as sensitizers
      • may predispose to an id reaction after systemic administration
  • 90. Allergens
    • Medications
    • Ethylenediamine
      • Common allergenic preservative
      • found in
        • aminophylline
        • some antihistamines
        • sometopical medicines
  • 91. Allergens
    • Medications
    • thimerosal
      • Preservative with the highest prevalence of positive patch tests
      • found in
        • vaccines
        • numerous topical medicines for the eyes, ears, and nose
  • 92. Allergens
    • Latex and rubber(caucho) chemicals
    • Latex fluid - Brazilian rubber tree - Hevea brasiliensis
    • Vulcanization
      • Chemical accelerators
      • Antioxidants
        • Thiurams
        • Carbamates
        • Mercaptobenzothiazole
          • *primary sensitizers
  • 93. Allergens
    • Latex and rubber(caucho) chemicals
    • Immediate hypersensitivity reactions
      • mediated - specific IgE against - latex protein
        • Responses
          • Urticaria
          • Rhinitis
          • Conjunctivitis
          • Asthma
          • Anaphylaxis
            • within minutes
  • 94. Allergens
    • Latex and rubber(caucho) chemicals
    • *airborne(aera) exposure proteins-Latex
    • latex gloves – to cause
      • immediate-type reactions
      • delayed-type reactions – ACD
      • > ƒ ICD.
  • 95. Allergens
    • Formaldehyde
    • Formaldehyde itself
    • formaldehyde–releasers = quaternium-15, are the most common
      • ƒ preservative ≠ thimerosal  ACD
        • cosmetics
        • moisturizers
        • fabrics (telas)
  • 96. Allergens
    • Fragrances
        • Cosmetics
        • Fabrics
        • topical medicines
        • flavorings (aromatizantes) of foods
        • drinks
        • spices (especias)
        • oral hygiene products
        • perfumes and colognes
  • 97. Allergens
    • Fragrances
      • Balsam of Peru >ƒ ACD - nonallergic contact urticaria
        • *In addition to mentioned products
          • Sunscreens
          • Shampoos
        • beneficial actions - side effects
          • stimulate capillary beds  increase local circulation
  • 98. Patch testing
    • gold standard – Dx ACD
    • first use
      • 1895
      • Josef Jadassohn
      • suspected - rash - result - mercury sensitivity
    • refined- simple
      • reproducing – ACD
        • allergen - same or cross-reacting
        • small area – back
  • 99. Patch testing
    • Standardized allergens- delivery vehicles
    • ACD eruption  appears - 2 to 3 days of sufficient allergen contact
      • patch testing - performed - at least a 3-day period
    • number of allergens - depends
      • physician’s clinical suspicion
      • likely culprits
  • 100. Patch testing
    • Screening panels - 20 to 30 - most prevalent allergens
      • >ƒ TRUE Test (Mekos Laboratories A/S, Hillerød, Denmark)
        • 23 allergens
        • one negative control
          • gel delivery system
        • Identifies about 70% - clinically relevant allergens
  • 101. Patch testing
    • *Another option  assortments(diversidad) of allergens
    • Filter paper in 8-mm aluminum disks  ‘‘Finn Chambers’’ (Epitest Ltd Oy, Tuusula, Finland)
      • allergen dispersion -Along - 5-mm ribbon of petrolatum -
  • 102. Patch testing
    • Techniques
    • Applied Allergens together
    • hairless region
    • upper back
    • between - spine and scapula
    • zone washed
  • 103. Patch testing
    • Techniques
    • An adhesive keeps the allergens secured
    • Edges(bordes) - marked with a pen.
    • Patients - return - physician’s office - 48 to 72 hours
      • Removed patch - Waiting 20 to 30 minutes reactions are graded
      • Third visit 24 to 96 hours later
  • 104. Patch testing
    • Techniques
    • longer allergic response
      • Elderly patients
      • allergens - late phase reactions
            • cobalt
            • neomycin
            • topical corticosteroids
  • 105. Patch testing
    • Precautions
    • Not be performed in - acute or widespread(extendida) contact dermatitis
      • Positive patch test reaction may progress to autoeczematization
    • Pruritus within minutes of application
      • suspicions - contact urticaria - possibility  anaphylaxis if patch is not removed
  • 106. Patch testing
    • to consider
    • bacitracin and gold are not TRUE Test panels  prevalent allergens
    • Poison ivy also is not included  urushiol’s sensitizing  may cause severe reactions
    • May need to be delayed - potent topical steroids -near test site
    • Systemic steroids
      • doses of 20 mg or less of prednisone daily - not inhibit positive reactions
  • 107. Patch testing
    • to consider
    • bacitracin and gold are not TRUE Test panels  prevalent allergens
    • Poison ivy also is not included  urushiol’s sensitizing  may cause severe reactions
    • May need to be delayed - potent topical steroids -near test site
    • Systemic steroids
      • doses of 20 mg or less of prednisone daily - not inhibit positive reactions
  • 108. MANAGEMENT
    • treating the active case
    • Prevention
    • treatment
      • Topical corticosteroids
      • Soap substitutes
      • Emollients
    • Second line treatments
      • topical PUVA
      • azathioprine
      • cyclosporin
        • steroid resistant chronic dermatitis
  • 109. MANAGEMENT
  • 110. MANAGEMENT
  • 111. MANAGEMENT
  • 112. MANAGEMENT
    • PREVENTION
    • workplace  eliminating harmful exposures
      • substitution of chemicals  less irritating or allergenic
      • introduction of engineering controls
      • Organization of work  all employees are exposed to the same degree
      • Uses of personal protection
        • Gloves
      • Selection of less susceptible individuals
  • 113. MANAGEMENT
    • correct selection of gloves
      • Cotton gloves
        • allow the skin to ‘‘breathe’’
        • could be used for dry work
        • Wet work  thin cotton gloves
          • absorb sweat
          • inside rubber or vinyl gloves
  • 114. MANAGEMENT
    • Barrier creams
      • questionable value in protecting against contact with irritants
    • After-work creams
      • Controlled clinical trials have shown benefit  reducing the incidence and prevalence
      • approved industrial skin cleansers
  • 115. MANAGEMENT
    • PRE-EMPLOYMENT SCREENING
      • predisposing factors
        • Atopic dermatitis
        • hand eczema
        • xerosis
  • 116. MANAGEMENT
    • WORK RELATED EDUCATIONAL PROGRAMMES
      • Half  OCDs  appear  first two years of employment
      • recognition of early signs and symptoms
      • proper use of protective clothing
      • after-work creams
      • personal and environmental hygiene