Reply: The rationale for distinguishing RB-ILD and AMP

<title>Extract</title> The 2025 European Respiratory Society/American Thoracic Society update on the classification of the interstitial pneumonias provides a comprehensive framework for the subcategorisation of these disorders, with particular focus on the corresponding histological and radiological patterns [1]. This classification includes continued separation of alveolar macrophage pneumonia (AMP), which was formerly termed desquamative interstitial pneumonia (DIP), and respiratory bronchiolitis–interstitial lung disease (RB-ILD). S. Mukhopadhyay and I. Sansano agree with the proposed change in terminology but have questioned the ongoing distinction between AMP and RB-ILD, arguing that these should be considered part of a single “smoking-related ILD” entity, along with inclusion of smoking-related interstitial fibrosis. Their primary rationale is based on the characteristic accumulation of macrophages within the alveolar spaces in all three of these entities and the frequent association of these findings with cigarette smoking [1]. Although S. Mukhopadhyay and I. Sansano raise important points for discussion, the committee was convinced by multiple arguments that RB-ILD and AMP should be kept as two distinct multidisciplinary diagnoses.