What is latex fruit syndrome?

Latex-Fruit Syndrome

Latex-fruit syndrome is a clinical condition characterized by cross-reactivity between natural rubber latex allergens and certain plant-derived food allergens, affecting approximately 30-50% of individuals with latex allergy and potentially causing serious systemic reactions including anaphylaxis. 1, 2

Definition and Mechanism

Latex-fruit syndrome occurs due to:

• Cross-reactivity of IgE antibodies that recognize structurally similar epitopes on proteins in both latex and certain fruits/vegetables 3
• Primary sensitization can occur to either latex or the cross-reactive foods, though latex sensitization often precedes food allergy 2
• The primary cross-reactive proteins involved include:
  • Class I chitinases containing hevein-like domains that cross-react with hevein (Hev b 6.02)
  • Beta-1,3-glucanases
  • Patatin-like proteins (Hev b 7)
  • Profilins (pan-allergens) 3

Common Cross-Reactive Foods

The most frequently implicated foods in latex-fruit syndrome include:

• Banana
• Avocado
• Kiwi
• Chestnut 4, 2

Additional foods with documented cross-reactivity:

• Papaya
• Peach
• Tomato
• Potato
• Bell pepper 1, 5, 3

Clinical Manifestations

Reactions can range from mild to severe:

• 73% of reactions manifest as systemic allergic symptoms 5
• 27% present as localized allergic reactions 5
• Manifestations include:
  • Oral allergy syndrome
  • Urticaria
  • Angioedema
  • Gastrointestinal symptoms
  • Respiratory symptoms
  • Anaphylaxis (potentially life-threatening) 6, 5

High-Risk Populations

Individuals at increased risk for latex allergy and consequently latex-fruit syndrome include:

• Patients with atopy
• Children undergoing multiple surgical procedures (e.g., spina bifida)
• Patients with severe hand dermatitis
• Healthcare professionals
• Industrial workers using protective gear
• Individuals with occupational exposure to latex 4

Diagnosis

Diagnostic approach includes:

• Detailed clinical history focusing on reactions to both latex products and cross-reactive foods
• Skin prick testing (SPT) with latex extracts (sensitivity 75-90%)
• Specific IgE blood tests for latex (though sensitivity can be as low as 50%)
• Food-specific IgE testing or SPT for suspected cross-reactive foods
• Challenge testing in selected cases 4

Management

The cornerstone of management is strict avoidance:

• Complete avoidance of latex products
• Avoidance of identified cross-reactive foods
• For healthcare settings:
  • Latex-free environment with synthetic gloves
  • Non-powdered latex gloves for colleagues if complete avoidance isn't possible
  • Latex-free emergency cart availability
  • For procedures: latex-free environment, first case of the day scheduling, and availability of emergency medications 4

Important Considerations

• Patients with latex allergy should be warned about potential cross-reactions with related fruits even if they haven't experienced reactions previously 6
• The severity of reactions can increase over time with continued exposure 6
• Specific IgE tests may be negative despite clinical reactivity, so negative test results don't rule out the syndrome 6
• Patients should wear medical alert identification and carry emergency epinephrine if they've experienced severe reactions 4

Pitfalls and Caveats

• Diagnosis can be challenging due to variable sensitivity of available tests
• The prevalence of latex-fruit syndrome varies widely (4-88%) in studies due to differences in diagnostic approaches and geographical regions 5
• Patients may be unaware of the connection between their latex allergy and food reactions
• Continued exposure to either latex or cross-reactive foods may increase sensitization and reaction severity 6
• Standardized diagnostic criteria and severity grading systems are still needed for optimal management 5