Abstract
Idiopathic pleuroparenchymal fibroelastosis (IPPFE) was added to the registry of designated intractable diseases by the Japan Intractable Disease Information Center in April 2024. To elucidate the current clinical practice related to this condition, we conducted a nationwide internet-based survey between June and September 2025. A total of 141 medical institutions across Japan responded, reporting 954 patients currently under follow-up and demonstrating a steady increase in diagnosed cases. Most patients were diagnosed using clinical diagnostic criteria, whereas pathological confirmation remained uncommon. The use of antifibrotic agents was often limited by decreasing body weight, frailty, or other patient-related factors. Among non-pharmacological interventions, nutritional counseling and other supportive measures were frequently implemented. Nevertheless, respondents noted considerable challenges in managing pneumothorax and advanced-stage disease. Weight loss and decline in pulmonary function were frequently cited as factors perceived to be useful for prognostic assessment. Free-text responses underscored the need for clearer diagnostic criteria, further validation of antifibrotic and emerging therapies, and enhanced strategies for comprehensive care. Collectively, these findings highlight the diagnostic and therapeutic challenges associated with IPPFE and emphasize the necessity for standardized diagnostic approaches, evidence-based treatment strategies, and structured multidisciplinary management frameworks.
