Latex Allergy: Diagnosis, Prevention, and Management Tara Hata, MD
Assistant Professor
Dept of Anesthesia, UIHC
March 27, 2001
Latex Allergy: Diagnosis, Prevention, and Management Tara Hata, MD
Assistant Professor
Dept of Anesthesia, UIHC
March 27, 2001
History of Latex Allergy
1933 Contact dermatitis to gloves
1979 Contact urticaria
1982 Identified IgE antibodies to latex proteins
1989 Anaphylaxis and death from latex exposure
Association with spina bifida or severe GU anomalies
1997 Reports to FDA total 2300 allergic reactions (225 anaphylaxis, 53 cardiac arrests, 17 deaths)
1998 FDA mandates labeling of medical products
Origin of Latex
Latex is sap from rubber tree, Hevea brasiliensis
60% H2O, 35% rubber, 5% protein
Rubber molecule: cis-1,4-polyisoprene
Chemicals added during production
Preservatives (ie: ammonia), accelerators (ie: thiurams), antioxidants (phenylenediamine), vulcanizing compounds (ie: sulfur)
May elicit delayed hypersensitivity
Proteins responsible for most generalized allergies
7 sensitizing proteins identified to date
Manufacture of Latex Gloves
Protein content can vary 1000-fold among lots
May vary 3000-fold among manufacturers
Powdered examination gloves have highest protein content and allergen levels
Cornstarch particles adsorb latex allergens
Particles aerosolized: assoc with respiratory symptoms
Particles also contaminate clothing
Lowest levels in powderless gloves that undergo additional washing and chlorination
Mechanisms of Exposure
Cutaneous absorption, ie: from gloves
Inhalation via aerosolized proteins on powder
Mucosal
Vaginal/rectal exams, dental procedures, surgery
Parenteral
IVs, surgical wounds, severe dermatitis
Hypersensitivity Classification
Type I Immediate
Type II Cytotoxic
Type III Immune complex
Type IV Delayed type
Types of Latex Sensitivity
Irritant contact dermatitis
Type IV -- Delayed Hypersensitivity
Type I --Immediate Hypersensitivity
Irritant Contact Dermatitis
Most frequent reaction to latex products
Sxs/signs: scaling, drying, cracking of skin
Results from direct action of latex and chemicals
Not a true allergy - no immunologic mechanism
However breakdown in skin integrity enhances absorption of latex proteins
Accelerates onset of sensitivity/allergy
Rx: identify reaction, use alternative product
Type IV -- Delayed Hypersensitivity
Synonyms: T-cell mediated contact dermatitis, allergic contact dermatitis
Most common immune response to gloves
Sxs/signs: mild to severe dermatitis (itching, blistering, crusting); appears 6-72 hrs after contact
Cause: processing chemicals in gloves;
mediated by T lymphocytes (not antibodies)
Rx: Identify chemical and use alternative product
Patients may progress to Type I allergy
Type I -- Immediate Hypersensitivity
Synonyms: IgE mediated anaphylactic reaction
Cause: proteins in latex
Antigen induces production of IgE; re-exposure to antigen triggers cascade: release of histamine, arachidonic acid, leukotrienes, prostaglandins
Onset within minutes
Varied response: local hives to anaphylactic shock
Rx: Antihistamines, steroids, anaphylaxis protocol
Prevention: avoid latex and areas where powdered gloves used
Type I Mediators
Histamine and tryptase release common to type I and IV
Prostaglandins, leukotrienes, eosinophilic chemotactic factor, platelet activating factor
potent bronchoconstrictors, vasodilators
Cytokines released minutes later also cause inflammatory effects
Patients with history of multiple surgeries
Meningomyelocele or severe urologic anomalies
Health care workers
Other occupational exposure
Rubber product workers, hair dressers, house cleaners
Individuals with atopy
Hay fever, rhinitis, asthma, or eczema
Patients with specific food allergies
Banana, kiwi, avocado, chestnut, etc.
Similar proteins
Myelodysplastic Patients
Prevalence of latex allergy is 18-64%
Type I reactions more common
Predisposing factors
multiple surgeries
daily catheterizations / stoma care
presence of atopy is synergistic factor
Other children at high risk
multiple surgeries starting in neonatal period
those with spinal cord injuries
Health Care Workers
Typically display a type IV reaction
Can include conjunctivitis, rhinitis, dermatitis
1998 study: prevalence of immediate sensitivity in anesthesiologists & CRNAs 12-16%
Over 80% of those sensitized had no sxs yet
Risk factors: hx atopy, skin sxs with latex gloves, tropical fruit allergies
Progression from type IV to type I unpredictable
Diagnosis of Latex Allergy
*Clinical history (ask the right questions)
Myelodysplasia / urologic anomalies
Multiple surgeries
Chronic occupational exposure
Previous reactions to latex products (type I)
Certain food allergies
Atopy
Refer to allergist
Skin testing
In vitro testing
Diagnosis by Skin Testing
Diagnose Type IV delayed hypersensitivity
Positive patch test
Reaction appears anytime from 8 hours to 5 days later
Diagnose Type I allergy
Skin prick test using antigens from glove products
Gold standard
Positive test: wheal and flare (c/t + and - controls)
Sensitivity and specificity around 98%
May result in severe reaction
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