Animal allergies: what if your diagnosis is wrong?

By Ana Espino | Published on April 10, 2026 | 3 min read


Allergies to domestic animals—particularly cats, dogs, and horses—are a major cause of allergic rhinitis and asthma, especially in children. Exposure to allergens is frequent and widespread, even in the absence of direct contact with animals, due to passive transfer mechanisms.  

Diagnostic strategies mainly rely on skin tests and specific IgE measurements, but these approaches have significant limitations. They cannot reliably distinguish between primary sensitization and cross-sensitization, increasing the risk of diagnostic errors.  

The main challenge lies in the frequent occurrence of polysensitization, driven by homologous allergens such as lipocalins and serum albumins, which are responsible for numerous cross-reactions. This complexity makes it difficult to identify the allergen truly responsible for symptoms.  

The aim of this study, recently published in The Turkish Journal of Pediatrics, is to better characterize sensitization profiles and propose an innovative diagnostic algorithm based on molecular allergology to improve clinical management.  

True sensitization or cross-reactivity: what do your tests really detect?  

This study is based on an extensive literature review integrating epidemiological, clinical, and molecular data on animal allergies. Analyses focused on specific IgE profiles, allergenic components, and mechanisms of cross-sensitization.  

The results show a high prevalence of sensitization, reaching approximately 26% for cats and 27% for dogs in Europe, with a direct impact on asthma severity. High levels of specific IgE—particularly against Fel d 1—are associated with more severe forms and increased bronchial hyperreactivity.  

Molecular analysis identifies key species-specific allergens: Fel d 1 for cats, Can f 4 and Can f 5 for dogs, and Equ c 4 for horses, which are considered markers of genuine sensitization.  

The data highlight the central role of lipocalins—highly conserved proteins responsible for numerous cross-species sensitizations. This cross-reactivity explains why up to 75% of patients exhibit multiple sensitizations, complicating clinical interpretation.  

Traditional tests appear insufficient, as they cannot distinguish co-sensitization from true immunological cross-reactivity. The introduction of molecular diagnostic techniques, particularly multiplex platforms, makes it possible to identify the primary sensitizing allergen and refine the diagnosis.  

The proposed algorithm combines conventional testing with molecular analysis. It recommends first identifying major allergens, then analyzing lipocalin and albumin profiles to clarify secondary sensitizations.  

Finally, the findings highlight the value of multiplex microarrays, which allow simultaneous analysis of multiple allergens, despite sometimes lower analytical sensitivity compared to singleplex tests.  

Toward truly precise diagnosis?  

Animal allergies are common conditions characterized by immunological complexity due to polysensitization.  

The main challenge is to accurately identify the primary sensitizing allergen—an essential step for appropriate management.  

The objective of this study was to improve diagnostic strategies. The results confirm that molecular diagnostics represent a major advance, enabling greater precision and more relevant therapeutic guidance, particularly for allergen immunotherapy.  

However, some limitations remain, including the lack of consensus on interpreting complex sensitization profiles, technical limitations of multiplex assays, and insufficient clinical validation of some proposed algorithms.  

Future perspectives include the development of standardized diagnostic protocols, improvements in molecular tools, and integration of these approaches into personalized medicine—optimizing patient stratification and therapeutic decision-making. 

Read next: Allergies: the molecular revolution is underway

About the author – Ana Espino
PhD in Immunology, specialized in Virology  
As a scientific writer, Ana is passionate about bridging the gap between research and real-world impact. With expertise in immunology, virology, oncology, and clinical studies, she makes complex science clear and accessible. Her mission: to accelerate knowledge sharing and empower evidence-based decisions through impactful communication.