Reevaluating diagnosis in interstitial lung disease with a second multidisciplinary discussion

Background: The importance of multidisciplinary discussion (MDD) for diagnosing interstitial lung disease (ILD) is emphasized by several international guidelines. While initial diagnoses are often provisional and require periodic re-evaluation, there is a lack of literature regarding the role of follow-up MDD in clinical practice. Methods: From September 2020 to January 2022, patients underwent an initial MDD (MDD1) based on clinical, radiological, and pathological evaluations. Each diagnosis was assigned a confidence level. One year later, a second MDD (MDD2) was conducted for re-evaluation, based on subsequent clinical and radiological information. Changes in diagnosis and confidence levels between MDD1 and MDD2 were assessed. Results: Among 52 patients enrolled in both MDDs, the diagnosis for 13 (25%) was revised at MDD2. Of these, 10 patients were initially diagnosed with unclassifiable ILD, and 3 received a low confidence diagnosis of either idiopathic pulmonary fibrosis or idiopathic nonspecific interstitial pneumonia. The most common diagnostic revision was due to the deterioration after antigen exposure or improvement after antigen avoidance, which resulted in a revised diagnosis of HP at MDD2. Conclusions: Our findings underscore the importance of periodic reassessment of MDD to improve the accuracy of ILD diagnosis. This study highlights the significance of longitudinal clinical and radiological evaluation for diagnostic revision, even in situations when rebiopsy is not feasible.