Nonspecific interstitial pneumonia: prognostic significance of high-resolution computed tomography in 59 patients

Relationship between idiopathic interstitial pneumonias (IIPs) and connective tissue disease-related interstitial lung disease (CTD-ILD): A narrative review

While idiopathic interstitial pneumonia (IIP) centering on idiopathic pulmonary fibrosis (IPF) is the most prevalent interstitial lung disease (ILD), especially in the older adult population, connective tissue disease (CTD)-related ILD is the second most prevalent ILD. The pathogenesis of IPF is primarily fibrosis, whereas that of other ILDs, particularly CTD-ILD, is mainly inflammation. Therefore, a precise diagnosis is crucial for selecting appropriate treatments, such as antifibrotic or immunosuppressive agents. In addition, some patients with IIP have CTD-related features, such as arthritis and skin eruption, but do not meet the criteria for any CTD, this is referred to as interstitial pneumonia with autoimmune features (IPAF). IPAF is closely associated with idiopathic nonspecific interstitial pneumonia (iNSIP) and cryptogenic organizing pneumonia (COP). Furthermore, patients with iNSIP or those with NSIP with OP overlap frequently develop polymyositis/dermatomyositis after the diagnosis of IIP. Acute exacerbation of ILD, the most common cause of death, occurs more frequently in patients with IPF than in those with other ILDs. Although acute exacerbation of CTD-ILD occurs at a low rate of incidence, patients with rheumatoid arthritis, microscopic polyangiitis, or systemic sclerosis experience more acute exacerbation of CTD-ILD than those with other CTD. In this review, the features of each IIP, focusing on CTD-related signatures, are summarized, and the pathogenesis and appropriate treatments to improve the prognoses of patients with various ILDs are discussed.

ACR Appropriateness Criteria® Diffuse Lung Disease

Diffuse lung disease, frequently referred to as interstitial lung disease, encompasses numerous disorders affecting the lung parenchyma. The potential etiologies of diffuse lung disease are broad with several hundred established clinical syndromes and pathologies currently identified. Imaging plays a critical role in diagnosis and follow-up of many of these diseases, although multidisciplinary discussion is the current standard for diagnosis of several DLDs. This document aims to establish guidelines for evaluation of diffuse lung diseases for 1) initial imaging of suspected diffuse lung disease, 2) initial imaging of suspected acute exacerbation or acute deterioration in cases of confirmed diffuse lung disease, and 3) clinically indicated routine follow-up of confirmed diffuse lung disease without acute deterioration. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

ACR Appropriateness Criteria® Chronic Dyspnea-Noncardiovascular Origin

Chronic dyspnea may result from a variety of disorders of cardiovascular, pulmonary, gastrointestinal, neuromuscular, systemic, and psychogenic etiology. This article discusses guidelines for the initial imaging of six variants for chronic dyspnea of noncardiovascular origin: (1) Chronic dyspnea of unclear etiology; (2) Chronic dyspnea with suspected chronic obstructive pulmonary disease; (3) Chronic dyspnea with suspected central airways disease; (4) Chronic dyspnea with suspected interstitial lung disease; (5) Chronic dyspnea with suspected disease of the pleura or chest wall; and (6) Chronic dyspnea with suspected diaphragm dysfunction. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Inspiratory resonant frequency of forced oscillation technique as a predictor of the composite physiologic index in interstitial lung disease

The composite physiologic index (CPI), which is derived from FEV1, FVC, and diffusing capacity, has been developed to predict the extent of fibrosis on high-resolution computed tomography (HRCT). However, the relevance to the forced oscillation technique (FOT) is not fully understood. We hypothesized that FOT would independently predict the CPI in interstitial lung disease (ILD). In this cross-sectional study we assessed the relationship between pulmonary function tests, forced oscillatory parameters, and the degree of fibrosis in ILD. Spirometry, evaluation of diffusing capacity for carbon monoxide, and the broadband frequency FOT were performed in 93 patients with a clinical/HRCT diagnosis of ILD. The CPI was calculated and fibrosis extent was measured by HRCT and scored. Univariate analyses revealed that, of the forced oscillatory parameters, inspiratory resonant frequency best correlated with FVC, FEV1, diffusing capacity, CPI, and fibrosis score. In multiple regression analyses, CPI was independently predicted by inspiratory resonant frequency and fibrosis score (model R(2)=0.405, p<0.0001).

Diaphragmatic motion studied by M-mode ultrasonography in combined pulmonary fibrosis and emphysema

BACKGROUND

The coexistence of emphysema and pulmonary fibrosis is known as combined pulmonary fibrosis and emphysema (CPFE). The aim of this study was to compare diaphragmatic motion measured by M-mode ultrasonography of patients with CPFE, idiopathic pulmonary fibrosis (IPF), and chronic obstructive pulmonary disease (COPD).

METHODS

Pulmonary function, high-resolution computed tomography (HRCT), and diaphragmatic motion were examined in patients with CPFE (n = 25), IPF (n = 18), and COPD (n = 60), and in healthy controls (n = 21). Diaphragmatic motions were measured on M-mode ultrasonographic images during quiet breathing and deep breathing.

RESULTS

There were no significant differences in right or left diaphragmatic motion during quiet breathing among the four groups, whereas differences were significant in right and left motion during deep breathing. Diaphragmatic motion in CPFE patients was the lowest among the four groups. COPD patients, especially those with severe COPD, showed significantly lower diaphragmatic motion than IPF patients or healthy controls. There were no differences in diaphragmatic motion between IPF patients and healthy controls. Right diaphragmatic motions during deep breathing were negatively correlated with emphysema scores (r = -0.606, p < 0.001), but were not correlated with fibrosis scores on HRCT.

CONCLUSIONS

Diaphragmatic weakness was found in CPFE patients. Emphysema but not fibrosis may be one cause of limited diaphragmatic motion in patients with CPFE. M-mode ultrasonographic evaluation of diaphragmatic motion during deep breathing may be a useful tool in diagnosing CPFE and in discriminating CPFE patients from IPF or COPD patients.

A cohort study of mortality predictors and characteristics of patients with combined pulmonary fibrosis and emphysema

OBJECTIVES

Our purpose was to assess the clinical data, predictors of mortality and acute exacerbation (AE) in combined pulmonary fibrosis and emphysema (CPFE) patients.

DESIGN

Single-centre retrospective cohort study.

SETTING

Teaching hospital in Japan.

PARTICIPANTS

We identified 93 CPFE patients with high-resolution computed tomographic (HRCT) through multidisciplinary discussion. Patients who had connective tissue disease, drug-associated interstitial lung disease and occupationally related interstitial lung disease, such as asbestosis and silicosis, were excluded.

INTERVENTIONS

There were no interventions.

METHODS

Medical records and HRCT scans from January 2002 through December 2007 were reviewed retrospectively at our hospital. Ninety-three patients had CPFE.

RESULTS

The mean age of CPFE patients was 74 years. Idiopathic pulmonary fibrosis and non-specific interstitial pneumonia were observed as distinct HRCT patterns. Forty-two patients showed finger clubbing. Mean serum Krebs von den Lungen-6 (KL-6) and per cent predicted forced vital capacity (%FVC) were 1089 IU/l, 63.86%, respectively. Twenty-two patients developed AE during observation period. Baseline KL-6 was a strong predictor of AE (OR=1.0016, p=0.009). Finger clubbing (HR=2.2620, p=0.015) and per cent predicted forced expiratory volume in one second/%FVC more than 1.2 (HR=1.9259, p=0.048) were independent predictors of mortality in CPFE.

CONCLUSIONS

Baseline serum KL-6 was a useful predictor of AE (cut-off =1050, receiver operator characteristic curve: 0.7720), which occurred in 24% (22/93) of the CPFE patients. Finger clubbing and per cent predicted forced expiratory volume in one second/%FVC more than 1.2 were independent predictors of mortality.