Nonspecific Interstitial Pneumonia and Idiopathic Pulmonary Fibrosis: Changes in Pattern and Distribution of Disease over Time
Abstract
Purpose: To retrospectively assess the change in disease pattern of nonspecific interstitial pneumonia (NSIP) and idiopathic pulmonary fibrosis (IPF) findings seen at thin-section computed tomography (CT) at long-term follow-up and to compare the same with initial findings at CT.
Materials and Methods: The study included 48 patients (28 men, 20 women; mean age, 57.5 years) with biopsy-proved NSIP (n = 23) or IPF (n = 25) who underwent CT at initial diagnosis and at follow-up 34–155 months later. The CT scans were randomized and reviewed by two independent thoracic radiologists for pattern and distribution of ground-glass opacity (GGO), reticulation, traction bronchiectasis and bronchiolectasis, and honeycombing. Statistical analysis was performed by using nonparametric methods and univariate logistic regression.
Results: Follow-up CT in patients with NSIP showed marked decrease in the extent of GGO, increase in reticulation, and a greater likelihood of peripheral distribution (all P < .05). At presentation, the CT findings were interpreted as suggestive of NSIP in 18 of 23 patients with NSIP and indeterminate or suggestive of IPF in five. In five (28%) of 18 patients with initial findings suggestive of NSIP, the follow-up CT scans were interpreted as more suggestive of IPF. No CT features seen at presentation allowed distinction between patients with NSIP that maintained an NSIP pattern at follow-up and those that progressed to an IPF pattern.
Conclusion: At follow-up CT, 28% of patients with initial CT findings suggestive of NSIP progressed to findings suggestive of IPF. Similar initial CT findings for NSIP may have different imaging outcomes.
© RSNA, 2008
References
- 1
. American Thoracic Society/European Respiratory Society International Multidisciplinary Consensus Classification of the Idiopathic Interstitial Pneumonias. This joint statement of the American Thoracic Society (ATS), and the European Respiratory Society (ERS) was adopted by the ATS board of directors, June 2001 and by the ERS Executive Committee, June 2001. Am J Respir Crit Care Med2002;165(2):277–304. [Published correction appears in Am J Respir Crit Care Med 2002;166(3):426.]American Thoracic Society; European Respiratory Society - 2
, Collard HR, King TE Jr. Classification and natural history of the idiopathic interstitial pneumonias. Proc Am Thorac Soc2006;3(4):285–292.Kim DS - 3
, Colby TV, du Bois RM, Hansell DM, Wells AU. The prognostic significance of the histologic pattern of interstitial pneumonia in patients presenting with the clinical entity of cryptogenic fibrosing alveolitis. Am J Respir Crit Care Med2000;162(6):2213–2217.Nicholson AG - 4
, Matsui K, Moss J, Ferrans VJ. Idiopathic nonspecific interstitial pneumonia: prognostic significance of cellular and fibrosing patterns. Am J Surg Pathol2000;24(1):19–33.Travis WD - 5
, du Bois RM, Nicholson AG, et al. Fibrotic idiopathic interstitial pneumonia: the prognostic value of longitudinal functional trends. Am J Respir Crit Care Med2003;168(5):531–537.Latsi PI - 6
, Wells AU. Nonspecific interstitial pneumonia: nobody said it's perfect. Am J Respir Crit Care Med2001;164(9):1553–1554.Nicholson AG - 7
, Zisman DA, Litzky LA, Nguyen BT, Kotloff RM. Usual interstitial pneumonia: histologic study of biopsy and explant specimens. Am J Surg Pathol2002;26(12):1567–1577.Katzenstein AL - 8
, Travis WD, Muller NL, et al. Idiopathic interstitial pneumonias: CT features. Radiology2005;236(1):10–21.Lynch DA - 9
, Zimmerman MB, Schwartz DA, et al. Utility of a lung biopsy for the diagnosis of idiopathic pulmonary fibrosis. Am J Respir Crit Care Med2001;164(2):193–196.Hunninghake GW - 10
, Rubens MB, Hansell DM, et al. Nonspecific interstitial pneumonia and usual interstitial pneumonia: comparative appearances at and diagnostic accuracy of thin-section CT. Radiology2001;221(3):600–605.MacDonald SL - 11
, Swensen SJ, Hansell DM, et al. Nonspecific interstitial pneumonia: variable appearance at high-resolution chest CT. Radiology2000;217(3):701–705. [Published correction appears in Radiology 2001;218(2):606.]Hartman TE - 12
, Hiorns MP, Lee KS, et al. Serial high resolution CT in non-specific interstitial pneumonia: prognostic value of the initial pattern. Clin Radiol2005;60(1):96–104.Screaton NJ - 13
, Lee KS, Chung MP, et al. Nonspecific interstitial pneumonia with fibrosis: high-resolution CT and pathologic findings. AJR Am J Roentgenol1998;171(6):1645–1650.Kim TS - 14
, Lynch DA, Newell JD Jr, et al. High-resolution computed tomography features of nonspecific interstitial pneumonia and usual interstitial pneumonia. J Comput Assist Tomogr2005;29(3):339–345.Elliot TL - 15
, Mumford JA, Murray S, et al. Prognostic implications of physiologic and radiographic changes in idiopathic interstitial pneumonia. Am J Respir Crit Care Med2003;168(5):543–548.Flaherty KR - 16
, Lee KS, Chung MP, Kwon OJ, Kim TS, Hwang JH. Nonspecific interstitial pneumonia with fibrosis: serial high-resolution CT findings with functional correlation. AJR Am J Roentgenol1999;173(4):949–953.Kim EY - 17
, Kondoh Y, Taniguchi H, et al. Serial high resolution CT findings in nonspecific interstitial pneumonia/fibrosis. J Comput Assist Tomogr2000;24(1):41–46.Nishiyama O - 18
, Inoue G, Yamamoto S, Sakatani M. Non-specific interstitial pneumonia: findings on sequential CT scans of nine patients. Thorax2000;55(10):854–859.Akira M - 19
, Lee KS, Muller NL, et al. Usual interstitial pneumonia and non-specific interstitial pneumonia: serial thin-section CT findings correlated with pulmonary function. Korean J Radiol2005;6(3):143–152.Jeong YJ - 20
, Müller NL, Friedman PJ, et al. Glossary of terms for CT of the lungs: recommendations of the Nomenclature Committee of the Fleischner Society. Radiology1996;200(2):327–331.Austin JH - 21
, Silman A. Statistical methods for assessing observer variability in clinical measures. BMJ1992;304(6840):1491–1494.Brennan P