Interstitial Lung Disease and Pulmonary Fibrosis: A Practical Approach for General Medicine Physicians with Focus on the Medical History

Abstract

Interstitial lung disease (ILD) and pulmonary fibrosis comprise a wide array of inflammatory and fibrotic lung diseases which are often confusing to general medicine and pulmonary physicians alike. In addition to the myriad of clinical and radiologic nomenclature used in ILD, histopathologic descriptors may be particularly confusing, and are often extrapolated to radiologic imaging patterns which may further add to the confusion. We propose that rather than focusing on precise histologic findings, focus should be on identifying an accurate etiology of ILD through a comprehensive and detailed medical history. Histopathologic patterns from lung biopsy should not be dismissed, but are often nonspecific, and overall treatment strategy and prognosis are likely to be determined more by the specific etiology of ILD rather than any particular histologic pattern. In this review, we outline a practical approach to common ILDs, highlight important aspects in obtaining an exposure history, clarify terminology and nomenclature, and discuss six common subgroups of ILD likely to be encountered by general medicine physicians in the inpatient or outpatient setting: Smoking-related, hypersensitivity pneumonitis, connective tissue disease-related, occupation-related, medication-induced, and idiopathic pulmonary fibrosis. Accurate diagnosis of these forms of ILD does require supplementing the medical history with results of the physical examination, autoimmune serologic testing, and chest radiographic imaging, but the importance of a comprehensive environmental, avocational, occupational, and medication-use history cannot be overstated and is likely the single most important factor responsible for achieving the best possible outcomes for patients.

Combined Pulmonary Fibrosis and Emphysema: Pulmonary Function Testing and a Pathophysiology Perspective

“…The effects of pulmonary fibrosis on gas exchange and mechanical properties of the lung are well characterized. Pulmonary fibrosis may be caused by a myriad of environmental exposures, medication toxicities, or autoimmune mechanisms, or may develop without a well-defined etiology and be identified as idiopathic pulmonary fibrosis (IPF) [29]. Pulmonary fibrosis is identified on chest CT imaging by a combination of findings including reticulation, volume loss, traction bronchiectasis, and honeycombing [30].…”

Impaired Right and Left Ventricular Longitudinal Function in Patients with Fibrotic Interstitial Lung Diseases

“…Among idiopathic interstitial pneumonia, idiopathic pulmonary fibrosis (IPF) is the most common form, affecting 30 persons per 100,000 in the general population, and as many as 175 persons per 100,000 in the age group of >75 years [2]. Despite recent advances in pharmacotherapy [3], IPF is a poor-prognosis disease, with a rapidly progressive and debilitating clinical progression [4][5][6][7].…”

Determinants of health-related quality of life decline in interstitial lung disease

“…Interstitial lung diseases (ILD) are a group of heterogeneous, rare diseases, which are characterized by pulmonary fibrosis and/or inflammation [1,2]. ILDs in general are associated with a high burden of disease reflected by a significant loss of years of life and high death rates.…”