The Multiple Trajectories of the Allergic March

Area of Science:

• Immunology
• Genetics
• Environmental Health

Background:

• The allergic march describes sequential allergic diseases, but its progression is highly variable.
• While nearly half of children have allergy symptoms, only 4-6% develop multiple allergic diseases.
• Allergic diseases share risk factors but often arise independently, defying a single linear path.

Purpose of the Study:

• To review the current understanding of the allergic march.
• To explore clinical observations, omics data, and risk factors influencing allergic disease progression.
• To discuss interventions for preventing allergic multimorbidity.

Main Methods:

• This narrative review synthesizes existing literature.
• It examines clinical data, omics findings, and etiological mechanisms.
• The review considers genetic and exposomic interactions in allergic disease development.

Main Results:

• Allergic march trajectories are heterogeneous, not following a single linear progression.
• TH2-mediated inflammation, barrier dysfunction, and genetics are key etiological factors.
• The exposome significantly interacts with these factors, influencing disease onset and progression.

Conclusions:

• Studying allergic diseases from an omics perspective is crucial for understanding diverse progression pathways.
• Identifying distinct trajectories can lead to targeted interventions for preventing allergic multimorbidity.
• Preventive strategies should consider individual genetic and environmental exposures.