Latex Allergy

Introduction^1,2

• Latex allergy is an IgE-mediated hypersensitivity reaction to latex proteins, commonly encountered in healthcare settings due to the widespread use of latex-containing products.
• Though the use of latex products has declined in the healthcare industry in many high-income countries, reduced incidence may lead to decreased provider awareness.
• Latex exists in a variety of rubber products, including medical gloves, condoms, balloons, catheters, and tubing.
• The main source of healthcare-associated latex exposure is the use of powdered latex gloves.

Epidemiology

• The prevalence of latex sensitization ranges from less than 1% to 7.6% in the general population, with a significantly higher prevalence (3-5 times) in populations with high latex exposure.^2,4

Etiology

Risk Factors^1,2

• Healthcare workers are at higher risk of latex allergy due to repetitive exposure and subsequent sensitization, with studies showing significantly elevated rates in medical careers, including surgeons, dentists, and nursing staff.
• Patients with a history of multiple surgical procedures or hospitalizations also have higher rates of latex sensitization.
• Patients with spina bifida, as well as other congenital anomalies and conditions (e.g., cloacal anomalies, esophageal atresia, omphalocele, gastroschisis, cerebral palsy) have a higher prevalence of latex allergy. It is recommended that latex-containing products be strictly avoided in patients with spina bifida.
• A family or personal history of atopy has also been shown to correlate with higher rates of latex sensitization.
• Other occupational risks include cleaners, housekeepers, hairdressers, food-handlers, latex factory workers.

Food-Allergy Risks^1,2

• Latex comes from the sap of rubber trees (Hevea brasiliensis) and therefore is found in many different “latex-producing” plants.
• Hundreds of allergens have been identified from natural rubber latex (NRL), 15 of which (Hevb1 to Hev b15) have been listed by the World Health Organization.
• Some foods have latex cross-reactivity, and allergies to these may suggest an increased risk of latex allergy in this population.
• Approximately 40% of patients with latex allergy are known to have latex-fruit syndrome caused by cross-reactivity with food allergens.
• Cross-reactive foods include avocado, banana, chestnut, passion fruit, kiwi, cassava, tomato, potato, bell pepper, mango, soy, and papaya.

Pathophysiology^2,3,4

• Exposure to latex may occur via cutaneous, percutaneous, mucosal, parenteral, or inhalational routes.
• Most exposure occurs through direct contact; however, airborne latex particles may cause both sensitization and reactions due to the high concentration of airborne particles and lubricant powders during the process of donning or doffing latex gloves.
• Most allergic reactions to latex are type I hypersensitivity reactions, where exposure to latex allergen proteins within the NRL triggers release of IgE immunoglobulin. Upon re-exposure to latex antigens, IgE antibodies bind to mast cells and basophils, releasing histamine and other inflammatory mediators, which leads to allergic symptoms and/or anaphylaxis.
• Type IV hypersensitivity reactions also present subacutely, resulting from the release of cytokines by T-cells and macrophages, which leads to inflammation and tissue damage that occurs over 24-48 hours and can last from 8 hours to 5 days.

Clinical Presentation^1,2

• Latex allergy may present with a variety of symptoms that range from mild to life-threatening:
  • Mild symptoms: Pruritus, skin erythema, urticaria, or rash
  • Serious symptoms: Sneezing, rhinorrhea, conjunctivitis, cough, wheezing, breathing difficulty
  • Life-threatening symptoms: Increasing difficulty breathing, diffuse hives, angioedema, nausea, vomiting, wheezing, dizziness, loss of consciousness, confusion, hypotension, circulatory collapse, death

Skin Manifestations^2,4,6

• Immunological contact urticaria (ICU): Type-I hypersensitivity reaction mediated by latex-specific immunoglobulin E upon physical contact to a patient’s skin
• Protein contact dermatitis: A controversial diagnosis that is considered a mix of type I and type IV hypersensitivity reactions presenting as recurrent itchy, vesicular, eczema-like attacks
• Irritant contact dermatitis: Type IV hypersensitivity reaction due to mechanical friction/drying and additives used in latex rubber production (e.g., 1,3-diphenylguanidine)

Respiratory Manifestations

• Respiratory manifestations of latex allergy include triggered asthma attacks, rhinitis, conjunctivitis, and cough. Eosinophilic bronchitis is a rare complication.²

Systemic Manifestations

• Anaphylaxis is a systemic IgE-mediated type I hypersensitivity reaction, characterized by the release of histamine and other preformed mediators that lead to the accumulation of leukotrienes and prostaglandins, resulting in increased vascular permeability, flushing, urticaria, angioedema, bronchoconstriction, and hypotension.⁵
• Latex-triggered anaphylaxis most commonly occurs during medical or surgical procedures.
• Cardiovascular collapse is the most common presentation in patients undergoing anesthesia for procedures or surgeries, though bronchospasm and rash may also occur.²

Diagnosis^2,4

• A thorough history should be obtained, including food allergies, previous operations, congenital conditions, atopy, and history of symptoms after exposure to latex products.
• Confirmatory diagnosis includes:
  • Skin tests: Patch test, prick test (sensitivity ~93%; specificity 100%)
  • Serology testing: latex-specific IgE assay (sensitivity 70-80%)
  • Provocation/challenge testing: glove test, rub test, bronchial and conjunctival provocation test (high-risk of causing anaphylaxis)

Treatment^2,4

• A validated method to confirm a latex allergy diagnosis should be used.
• Latex exposure in allergic patients should be prevented through:
  • Patient education
  • Identification of at-risk patients
  • Creation of latex-free hospital/clinic environments
• Using latex-free alternatives that include vinyl, plastic, and silicone should be prioritized; however, these alternatives may offer reduced protection against viral particles.⁴
• In the event of anaphylaxis, clinicians should:
  • remove latex material from the patient;
  • administer 100% oxygen;
  • support the airway;
  • begin volume resuscitation;
  • administer epinephrine; and
  • place the patient in the Trendelenburg position.⁵
• Please see the OA summary Perioperative Allergies and Anaphylaxis. Link

Anesthetic Considerations

• It is essential to gather a comprehensive preoperative history to identify patients at risk for latex allergy.
• For patients with identified latex allergy, those with medical or occupational conditions that increase their predisposition to latex sensitization, and individuals at risk of cross-reactive latex allergy, it is recommended to avoid using latex-containing products whenever possible and to have appropriate pharmacotherapy available in case of complications.
• Most medical equipment includes warning labels for latex content.
• Many commonly used materials in anesthesia may contain latex, including adhesives, balloons, Foley catheters, gloves, IV tubing, masks, syringes, and tourniquets. Clinicians should be aware of nonlatex alternatives to these materials when required.⁴
• The use of latex gloves during intubation can expose the respiratory epithelium, potentially leading to sensitization or respiratory compromise in previously sensitized patients.
• Patients who experience latex-induced anaphylaxis should be discharged with an epinephrine auto-injector.