latex allergy

Prepared By :-Yogesh Malani 1

L. D. COLLEGE OF ENGINEERING

RUBBER TECHNOLOGY

Sub:- l.t.(Latex technology)


Topic:- Latex Allergy


History of Latex Allergy

1933 Contact dermatitis to gloves1979 Contact urticaria1982 Identified IgE antibodies to latex proteins1989 Anaphylaxis and death from latex exposureAssociation with spina bifida or severe GU anomalies1997 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


Risk Groups for Latex Allergy• 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


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


Non-latex Equipment

• Disposable endotracheal tubes• Esophageal stethoscopes• Oral airways• Suction catheters, Nasogastric tubes• ECG pads• Temp probes• LMAs


Pretreatment• Prophylaxis of anaphylaxis is controversial– Efficacy unknown– Anaphylaxis has occurred in pretreated pts– May mask early signs

• Pretreat pts with hx of Type I sxs• Start prophylaxis preop and continue x 24 hr– Diphenhydramine 1 mg/kg q 6 hr IV or PO– Methylprednisolone 1 mg/kg q 6 hr IV or PO– Cimetidine 5 mg/kg q 6 hr IV or PO (up to 300 mg)


Conclusion

• Most important step is avoidance of exposure in susceptible patients

• With universal precautions, the problem will likely worsen

• Hospitals should strive for low allergen environments– Powderless gloves with low extractable protein content

• Protect yourself– Treat dermatitis– Cover hand wounds with tegaderm

latex allergy

Education

yogesh malani

origin of latex latex

latex antigen

latex technology

absorption of latex

delayed type

delayed hypersensitivity

immediate type