Clinical Practice Guideline for the diagnosis of Granulomatous-Lymphocytic Interstitial Lung Disease (GLILD) in patients with Common Variable Immunodeficiency Disorders (CVID) - an ERS Clinical Research Collaboration

Background: Granulomatous-Lymphocytic Interstitial Lung Disease (GLILD) is a lung disease first described in people affected by common variable immunodeficiency disorders (CVID). Despite growing recognition of GLILD, there is no accepted diagnostic and management guideline, and current practice varies significantly across centres and countries. Objective: This clinical practice guideline provides evidence- and consensus-based recommendations on the screening and diagnosis of GLILD in patients with CVID. Methods: A panel representing multiple interdisciplinary perspectives convened with methodologists to prioritize clinical questions, review and assess the evidence using GRADE (Grading of Recommendations Assessment, Development and Evaluation) methodology. Evidence-to-Decision frameworks were used to decide on the direction and strength of recommendations. Results: Screening for GLILD is recommended in all adult CVID patients, preferably using high resolution computed tomography. Evaluation should be performed by a multidisciplinary team. Routine lung biopsies are not mandatory but necessary for atypical presentations. As part of the diagnostic process, pulmonary infections should be excluded and lymphocytic alveolitis sought after by means of bronchoalveolar lavage. The severity of lung function impairment should be evaluated using pulmonary function tests including gas transfer assessment. Most of the recommendations are graded as conditional because of low certainty in the evidence regarding health effects. Conclusions: This guideline allows for international homogeneity in the diagnosis of GLILD, thereby paving the way for improved comparability between centers, improving equity in health care for those affected by GLILD and facilitating multicenter research collaborations for future studies.