Familial pulmonary fibrosis: Clinical and radiological characteristics and progression analysis in different high resolution-CT patterns

Background Familial pulmonary fibrosis (FPF) is defined as an idiopathic diffuse parenchymal lung disease affecting two or more members of the same primary biological family. The aim of the present study was to contribute to the clinical, functional and radiological characterisation of FPF with particular regards to disease progression and survival. Methods Baseline clinical, functional and radiological data of a FPF population (n = 46 patients) were retrospectively collected and analysed according to the 2011 IPF guidelines HRCT classification. A PFT follow-up after 1-year and survival analysis was conducted among to different HRCT patterns. Results 22 female and 24 male patients (age at diagnosis 58.5 ± 9.7 years-old), belonging to 30 families, were included in this study. Radiological analysis demonstrated the presence of a UIP pattern at HRCT in 54.3% of patients, Poss-UIP in 21.8% and Incon-UIP in 23.9%. Incon-UIP patients were younger and more frequently female. Pulmonary function tests showed a restrictive ventilatory defect in patients with UIP and Incon-UIP patterns, while Poss-UIP patients had normal volumes with only a mild reduction of DLCO. BAL composition revealed increased lymphocytes percentage in Incon-UIP patients. Respiratory functional 1-year follow-up showed a significant worsening in UIP patients only. HRCT pattern progression was only demonstrated from Poss-UIP to UIP (18% of patients). Median survival was not statistically different among the 3 HRCT groups, although Poss-UIP patients presented a better outcome. Conclusions FPF has been confirmed to be a complex condition with poor prognosis. The present study firstly analysed functional and radiological follow-up data of patients with FPF, showing that it may manifests with several HRCT patterns with different rates of progression, in which Possible UIP and UIP could be considered phases of the same disease and Inconsistent UIP patients may represent a different clinical and radiological condition.