ASIA syndrome (autoimmune/inflammatory syndrome induced by adjuvants): Narrative literature review

Introduction

Adjuvant-induced autoimmune/inflammatory syndrome (ASIA) comprises a spectrum of clinical manifestations associated with exposure to diverse adjuvants that have in common the generation of non-specific autoantibodies and loss of immune tolerance.

Objective

This study aimed to develop a narrative review of the literature about the pathogenesis underlying ASIA syndrome, its differentiation from other defined autoimmune diseases, and prospects for future research in this field.

Materials and methods

A narrative review of the literature was conducted using Pubmed, Embase, and LILACS. All publications on the subject were included, with no time limit in English and Spanish. Finally, 25 articles published since 1990 were included, from which we reviewed the pathogenesis, diagnostic criteria, and its differentiation from other defined autoimmune processes.

Results

The appearance of ASIA syndrome seems to be linked to an individual’s genetic predisposition (HLA-DRB1*01 or HLA-DRB4) and is the result of the interaction of external and endogenous factors that trigger autoimmune phenomena. In recent years, physicians have become more aware of the relationship between exposure to adjuvants and the development of underlying signs and symptoms that may correspond to ASIA syndrome. The current evidence supporting its existence is still contradictory. A timely diagnosis requires a multidisciplinary approach and could require immunosuppressive treatment in particular cases.

Conclusions

In recent years a relationship between exposure to adjuvants and the appearance of autoimmunity phenomena has been recognized. In clinical practice, physicians can find cases of ASIA syndrome. However, the evidence is still debated on the relationship between adjuvants and autoimmune clinical manifestations. ASIA syndrome classification criteria require validation in various populations before being applied to select patients for clinical studies. It is necessary to identify the risk factors for ASIA syndrome to understand its pathophysiology and make a timely diagnosis.