OR24

1:Pulmonology Department, Local Health Unit Cova da Beira, Covilhã, Portugal; 2:Pulmonology Department, Local Health Unit São João, Porto, Portugal; 3:EPIUnit ITR, Instituto de Saúde Pública da Universidade do Porto, Universidade do Porto, Rua das Taipas, n° 135, 4050-600 Porto, Portugal; 4:Estudo das Populações - Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Porto, Portugal; 5:Public Health Unit, Local Health Unit Barcelos/Esposende, Barcelos, Portugal; 6:Department of Pulmonary Disease and Tuberculosis, University Medical Centre Groningen, University of Groningen, Groningen, Netherlands; 7:Tuberculosis Centre Beatrixoord, University Medical Centre Groningen, University of Groningen, Groningen, Netherlands; 8:Mayo Clinic, Rochester, MN, USA; 9:Department of Biomedical Sciences, Humanitas University, Via Rita Levi Montalcini 4, 20072, Pieve Emanuele, Milan, Italy; 10:IRCCS Humanitas Research Hospital, Respiratory Unit, Via Manzoni 56, 20089, Rozzano, Milan, Italy; 11:Department of Respiratory Diseases, Amiens-Picardie University Hospital, Amiens, France UR 4294 AGIR, Picardie Jules Verne University, Amiens, France; 12:Division of Mycobacterial and Respiratory Infections, Department of Medicine, National Jewish Health, Denver, Colorado, USA; 13:Division of Infectious Diseases, Department of Medicine, University of Colorado, Aurora, Colorado, USA; 14:Division of Pulmonary Sciences and Critical Care Medicine, Department of Medicine, University of Colorado, Aurora, Colorado, USA; 15:Radboudumc Community for Infectious Diseases, Department of Medical Microbiology, Radboud University Medical Centre, Nijmegen, The Netherlands; 16:Division of Clinical Infectious Diseases, Research Centre Borstel, Borstel, Germany; 17:German Centre for Infection Research (DZIF), Partner Site Borstel-Hamburg-Lübeck-Riems, Borstel, Germany; 18:Respiratory Medicine and International Health, University of Lübeck, Lübeck, Germany; 19:Department of Pediatrics, Global and Immigrant Health, Global Tuberculosis Program, Baylor College of Medicine and Texas Children's Hospital, Houston, TX, USA; 20:Department of Respiratory Medicine, The Royal Free Hospital NHS Trust, London, & University College London, London UK; 21:Royal Brompton Hospital and NHLI, Imperial College London, London, UK; 22:Clinic for Respiratory Diseases, University Hospital Centre Zagreb, Zagreb, Croatia; 23:University of Zagreb, School of Medicine, Zagreb, Croatia; 24:Respiratory Disease Centre, Fukujuji Hospital, Japan Anti-Tuberculosis Association, Japan; 25:Department of Clinical Mycobacteriosis, Nagasaki University Graduate School of Biomedical Sciences, Japan; 26:Division of Clinical Research, Fukujuji Hospital, Japan Anti-Tuberculosis Association, Japan; 27:Gallipoli Medical Research and Greenslopes Clinical Unit, The University of Queensland, Brisbane Australia; 28:Division of Infectious Diseases, Department of Internal Medicine II, Freiburg University Medical Centre, Freiburg, Germany; 29:Department of Epidemiology, Helmholtz Centre for Infection Research Braunschweig, Germany; 30:Division of Infectious Diseases, Department of Medicine, Oregon Health & Science University, Portland, Oregon, USA; 31:Centre for Infectious Disease Studies, Oregon Health & Science University-Portland State University School of Public Health, Portland, Oregon, USA; 32:Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Republic of Korea; 33:Centro de Saúde Pública Doutor Gonçalves Ferreira – Instituto de Saúde Pública Doutor Ricardo Jorge, INSA Porto, Porto, Portugal

Background: Treatment of nontuberculous mycobacterial pulmonary disease (NTM-PD) remains complex, with high failure rates and limited evidence guiding the management of refractory cases.

Objective: This study aimed to develop a consensus-based framework to support clinical decision-making in the context of treatment failure.

Methods: An e-Delphi process was conducted with a panel of 16 international experts in NTM-PD. Initial statements were developed based on responses to an open-ended questionnaire and informed by a systematic literature review. The statements were refined over three iterative rounds using a Likert scale questionnaire and additional written feedback, with the process continuing until consensus was reached across all key domains for NTM-PD management when facing treatment failure.

Results: Treatment failure was defined primarily as the lack of culture conversion after six months of adequate therapy, with clinical or radiological deterioration as supportive, non-essential criteria. Therapeutic decisions should rely on expert consultation. The framework outlines three therapeutic paths: treatment intensification, maintaining curative intention through personalised, species-specific multidrug regimens; de-escalation of treatment with the objective of symptomatic control, through simplified antibiotic schemes, and in selected cases, treatment discontinuation; supportive care for all the patients, including rehabilitation, nutritional and psychological support. Decisions should be guided by patient preference, disease severity, comorbidities, previous antibiotic treatment and documented resistance.

Conclusion: This consensus provides a structured, patient-centred approach for managing refractory NTM-PD. It supports personalised care pathways and standardises decision-making. Further studies are needed to validate this framework in clinical practice and to explore host-directed and alternative therapies.