SIMILARITY INDEX TO DEFINITE USUAL INTERSTITIAL PNEUMONIA (SI-UIP): A NOVEL PROGNOSTIC TOOL PROPOSED BY THE AUSTRALIAN IDIOPATHIC PULMONARY FIBROSIS REGISTRY

The Idiopathic Pulmonary Fibrosis (IPF) diagnostic guidelines specify the radiological and histological features, which, in the appropriate clinical context, are necessary for a diagnosis of IPF. We have previously demonstrated that in the Australian IPF Registry (AIPFR) outcomes did not differ whether patients met the IPF diagnostic guideline criteria. In this study we propose a similarity index to definite usual interstitial pneumonia (SI-UIP) on HRCT and evaluate its utility for the prognostication of patients with IPF. This study demonstrates the potential utility and short-comings of SI-UIP in the diagnosis and prognostication of real-world IPF patients.