Extract
The recent European Respiratory Society (ERS)/European Alliance of Associations for Rheumatology (EULAR) clinical practice guidelines for connective tissue disease-associated interstitial lung disease (CTD-ILD) represent a commendable collaborative effort and an important step toward harmonising clinical practice and improving outcomes for patients with these complex disorders [1, 2]. We commend the authors for addressing key aspects of disease assessment and treatment.
Shareable abstract
The ERS/EULAR recommendations mark a significant advancement in the field of CTD-ILD. However, the establishment of a harmonised and precise definition of rapidly progressive ILD remains a critical unmet need. https://bit.ly/497SD3C
To the Editor:
The recent European Respiratory Society (ERS)/European Alliance of Associations for Rheumatology (EULAR) clinical practice guidelines for connective tissue disease-associated interstitial lung disease (CTD-ILD) represent a commendable collaborative effort and an important step toward harmonising clinical practice and improving outcomes for patients with these complex disorders [1, 2]. We commend the authors for addressing key aspects of disease assessment and treatment.
However, we would like to raise a point of clarification and concern regarding the terminology and definition of rapidly progressive interstitial lung disease (RP-ILD). While the document acknowledges the heterogeneity of ILD in connective tissue diseases, there remains a notable gap in the standardised definition of RP-ILD. Given their central role in setting clinical standards and guiding research, respiratory societies have the legitimacy to lead and manage the development of a consensus definition for RP-ILD.
The manuscript currently uses several overlapping and somewhat ambiguous terms, such as “acute or subacute onset”, “rapidly evolving lung involvement” and “progressive pulmonary disease”. In contrast, for idiopathic pulmonary fibrosis (IPF), there is a widely accepted consensus definition of acute exacerbation, which has facilitated consistency in clinical care, research and clinical trials [3, 4]. A comparable level of clarity is still lacking for RP-ILD, particularly in the setting of idiopathic inflammatory myopathy-associated ILD (IIM-ILD).
Given the high morbidity and mortality associated with RP-ILD in IIMs – such as in anti-MDA5 dermatomyositis – the absence of a unified definition not only impedes comparability across clinical studies but also delays early identification and standardised management of high-risk patients. This gap is especially consequential for observational registries, biomarker discovery and the design of therapeutic trials.
Footnotes
Conflicts of interest: Y. Uzunhan reports grants from Oxyvie, consultancy fees from Boehringer Ingelheim and Pfizer, payment or honoraria for lectures, presentations, manuscript writing or educational events from Sanofi, Boehringer Ingelheim and CSL Vifor, support for attending meetings from Oxyvie and Boehringer Ingelheim, and participation on a data safety monitoring board or advisory board with Boehringer Ingelheim. H. Nunes reports research grants (paid to institution) from Boehringer Ingelheim, Roche, Bristol Myers Squibb and Pliant Therapeutics, consultancy fees, payment or honoraria for lectures, presentations, manuscript writing or educational events, and support for attending meetings from Boehringer Ingelheim, and participation on a data safety monitoring board or advisory board with Boehringer Ingelheim, Galapagos and Ferrer. The remaining authors have no potential conflicts of interest to disclose.
References
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