- D3.508 - Management of Severe Occupational Allergic Rhinitis and Asthma in a Veterinary Student: A Molecular-Guided Approach

Background: Veterinary medicine trainees are at increased risk of occupational allergy because of intense exposure to animal allergens. Component-resolved diagnostics may disentangle true sensitization from cross-reactivity and support precision management in severe disease.

Case: A 21-year-old male veterinary medicine student developed severe rhinoconjunctivitis, contact urticaria and uncontrolled asthma with prominent workplace worsening. After a major exacerbation (SpO₂ 85%) in November 2025 requiring 1-week hospitalization, oxygen and systemic corticosteroids, asthma was diagnosed in January 2026. Despite maintenance budesonide/formoterol and intranasal corticosteroids, he reported paroxysmal sneezing, dyspnea and angioedema on cat/dog exposure in the veterinary clinic at school; symptoms were notably milder when he was at home with his two cats. Non-animal triggers included dust, smoke, strong odours and exercise. Serum total IgE was 461 IU/mL and peripheral blood eosinophil count was 0.42×10³/µL. Skin prick testing was positive to cat (7×7 mm), dog (4×4 mm) and horse (4×4 mm), and to grass pollens and birch. Multiplex molecular allergen profiling (ALEX-3) showed high IgE to major cat and dog allergens (Fel d 1 33.54 kUA/L; Can f 1 29.95 kUA/L) with broad co-sensitization to lipocalins (Fel d 4, Fel d 7, Can f 6) and serum albumins (Fel d 2, Can f 3, Bos d 6), supporting a polysensitized phenotype with relevant cross-species reactivity. The markedly elevated Fel d 1 and Can f 1 levels indicate that the patient's severe clinical manifestations were primarily driven by major species-specific components. In addition, concomitant sensitization to lipocalins (Fel d 4, Fel d 7, Can f 6) and serum albumins (Fel d 2, Can f 3, Bos d 6) explains the broad cross-species symptom exacerbation and the extensive occupational risk burden. Given severe, uncontrolled disease in a high-exposure setting, add-on anti-IgE therapy with omalizumab was initiated for rapid asthma control, with subsequent planning of cat allergen immunotherapy as a disease-modifying strategy.

Conclusion: This case illustrates how molecular profiling can identify clinically dominant components and cross-reactive allergen families in occupational animal allergy, enabling risk-focused counselling and tailored therapy. A precision, molecule-guided approach may help maintain respiratory stability and allow continuation of veterinary school training while minimizing occupational morbidity.