Progranulin and Activin A Concentrations are Elevated in Serum from Patients with Acute Exacerbations of Idiopathic Pulmonary Fibrosis.

PURPOSE: Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive fibrotic lung disease of unknown cause with a variable course. Acute exacerbations of IPF (AE-IPF) is sudden accelerations of the disease or a superimposed idiopathic acute injury significantly reducing lung function. To examine the serum concentrations of Progranulin (PGRN) and activin A in patients with AE-IPF in a pilot study. METHODS: Twenty-one patients with AE-IPF were compared with 23 patients with stable IPF as a control group. Serum PGRN and activin A levels, arterial blood gas measurements, and lung function were determined in these two groups. RESULTS: Peripheral blood PGRN and activin A levels in patients with AE-IPF were 83.7 + 10.0 and 14.2 ± 1.7 ng/ml (mean + SD), respectively; higher than those in the control group 61.0 + 5.8 and 5.8 + 1.0 (p < 0.001). PGRN and activin A levels were significantly negatively correlated with carbon monoxide diffusion capacity r = - 0.857 (p < 0.001) and r = - 0.757 (p < 0.001). CONCLUSION: Progranulin (PGRN) and activin A may be involved in the pathogenesis of AE-IPF. They may be possible markers of disease activity in AE-IPF.