Functional impairment in fibrosing alveolitis: relationship to reversible disease on thin section computed tomography

Abstract

Thin-section computed tomography (CT) provides a reproducible method of quantifying global disease extent and can also discriminate between fibrotic disease, with predominance of reticular abnormalities, and reversible inflammatory cell infiltration, shown as ground-glass attenuation.The aim of this study was to determine whether functional impairment varied according to the presence of ground-glass attenuation on CT, independently of extent of disease on CT, demographic factors, smoking history, therapeutic status, and the type of fibrosing alveolitis (lone cryptogenic fibrosing alveolitis (CFA) versus fibrosing alveolitis associated with systemic sclerosis (FASSc)).Patients with concurrent emphysema on CT (n=16) and FASSc patients with end-stage pulmonary hypertension (n=5) were excluded. One hundred and eleven patients were studied (CFA, n=54; FASSc, n=57).The severity of functional impairment did not vary independently with the presence of predominant ground-glass attenuation, mixed appearance and predominant reticulation on CT. In 34 treated patients undergoing serial CT scanning, the severity of functional impairment did not differ independently between patients with and without regression of ground-glass attenuation at follow-up.We conclude that the severity of functional impairment does not discriminate between inflammatory and fibrotic disease in fibrosing alveolitis, as judged by initial and serial computed tomographic scanning, after adjustment for the morphological extent of disease on computed tomography.

Sarcoidosis: assessment of disease severity using HRCT

“…To evaluate disease progression, adding such subscore might be of additional value. In other studies by Wells et al [18,19] it was shown that CT appearances were of prognostic value in fibrosing alveolitis and that they are likely to play an increasing role in disease staging in these conditions. The therapeutic dilemma for clinicians who manage patients with sarcoidosis is when to prescribe steroids and/or immunosuppressive agents, which are widely used to treat fibrosis and may have a role in slowing the progression of the inflammation involved in the pathophysiological process of sarcoidosis towards fibrotic disease; thus, accurate staging of the disease extent is mandatory to guide therapeutic strategies aimed to avoid potentially preventable functional impairment in sarcoidosis.…”

“…The HRCT uses short scanning times and thin collimation, making it possible to demonstrate lung parenchyma in detail and detect abnormal changes of the lung parenchyma at an early stage [4,5,6,7,8,9,10,11]. Moreover, in several diffuse lung diseases HRCT abnormalities appeared to be useful in evaluating parameters of disease activity and functional impairment to predict prognosis, and in assessing response to therapy [12,13,14,15,16,17,18,19].…”

Computed tomography of diffuse lung disease: functional correlates

“…Such correlations take no account of the regional inhomogeneity of fibrosing lung disease and account for the discrepant results between studies that have sought relationships between histopathological severity of disease and physiological disturbance [71,72]. This is in contrast to more recent work which has shown much stronger correlations between PFT data and global assessment with CT of disease extent [68,73].…”

Imaging the inflammatory activity of sarcoidosis

“…These studies, with relatively small numbers of patients, demonstrated that architectural distortion, honeycombing, traction bronchiectasis and large cysts are invariably irreversible, (micro)nodular disease is in most cases reversible, but ground-glass, irregular linear opacities and interlobular septal thickening can be reversible but quite often are not and can progress to fibrosis [11][12][13][14][15][16]. Thus, evaluating the reversibility of disease by HRCT appears to be possible only in retrospect with serial data.…”