CC BY-NC-ND 4.0 · Indian J Radiol Imaging 2023; 33(01): 070-075
DOI: 10.1055/s-0042-1758876
Original Article

Diagnostic Value of Connective Tissue Disease Related CT Signs in Usual Interstitial Pneumonia Pattern of Interstitial Lung Disease

1   Department of Radiodiagnosis, Christian Medical College and Hospital, Vellore, Tamil Nadu, India
,
1   Department of Radiodiagnosis, Christian Medical College and Hospital, Vellore, Tamil Nadu, India
,
Aparna Irodi
1   Department of Radiodiagnosis, Christian Medical College and Hospital, Vellore, Tamil Nadu, India
,
John Mathew
2   Department of Clinical Immunology and Rheumatology, Christian Medical College and Hospital, Vellore, Tamil Nadu, India
,
Mini Pakkal
3   Joint Department of Medical Imaging, Toronto General Hospital, Toronto, Ontario, Canada
› Author Affiliations
Funding None.

Abstract

Purpose Usual interstitial pneumonia (UIP) pattern of interstitial lung disease (ILD) can have varied etiology, with connective tissue disease (CTD) being a common known cause. The anterior upper lobe (AUL) sign, exuberant honeycombing (EHC), and straight edge (SE) sign are recently described computed tomography (CT) signs in CTD-related UIP. We test the diagnostic value of these CT signs for CTD in patients with UIP and compare the incidence of these signs between CTD-related UIP and non–CTD-related UIP. We also evaluated the interobserver agreement in detection of these CT signs.

Methods Retrospective study of all patients who had UIP pattern of ILD on CT thorax done from January 1, 2016 to January 31, 2019, was grouped into two: non–CTD-related UIP or CTD-related UIP. CT thorax was reviewed for the presence of these signs—AUL, SE, and EHC. The diagnostic values of these signs in diagnosing CTD-related UIP was assessed. For assessment of interobserver agreement, another radiologist reviewed a subset of 30 randomly selected cases and looked for the presence of these signs.

Results Of the 156 patients included, 76 had CTD. The incidence of CT signs were significantly higher in CTD-related UIP. The specificities of AUL, EHC, and SE were 82.5, 75, and 85%, respectively. The EHC sign had highest sensitivity of 48.7%. Inclusion of more than one sign increased the specificity of diagnosis of CTD-related UIP; however, the sensitivity decreases. There was excellent interobserver agreement (0.81–0.87) for each of these signs.

Conclusion The presence of SE, AUL, and EHC signs in cases with UIP pattern are specific imaging markers to diagnose underlying CTD; however, due to its low sensitivity, the absence of these signs cannot exclude the same. Because of its excellent interobserver agreement, these signs are reliable in the evaluation of CTD-related ILD.

Note

A part of this study was presented in competitive oral paper presentation during Third Annual National Conference of Society of Chest Imaging and Intervention (SCII CON 2021) and won second prize.


Authors Contributions

All the authors contributed to the study conception and design. Material preparation, data collection and analysis were performed by A.A. and L.R.V. The first draft of the manuscript was written by A.A. and L.R.V., and all the authors commented on previous versions of the manuscript. All the authors read and approved the final manuscript.


Ethical Approval

This study was performed in line with the principles of the Declaration of Helsinki. Approval was granted by the Ethics Committee or Institutional Review Board of Christian Medical College, Vellore (September 15, 2020, No. 13306).


Informed Consent

Written informed consent was waived by the Institutional Review Board.


Study Design

This is a retrospective, cross-sectional study performed at one institution.




Publication History

Article published online:
26 December 2022

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  • References

  • 1 Wuyts WA, Cavazza A, Rossi G, Bonella F, Sverzellati N, Spagnolo P. Differential diagnosis of usual interstitial pneumonia: when is it truly idiopathic?. Eur Respir Rev 2014; 23 (133) 308-319
  • 2 Raghu G, Remy-Jardin M, Myers JL. et al; American Thoracic Society, European Respiratory Society, Japanese Respiratory Society, and Latin American Thoracic Society. Diagnosis of idiopathic pulmonary fibrosis. an official ATS/ERS/JRS/ALAT clinical practice guideline. Am J Respir Crit Care Med 2018; 198 (05) e44-e68
  • 3 Lynch DA. Lung disease related to collagen vascular disease. J Thorac Imaging 2009; 24 (04) 299-309
  • 4 Kono M, Nakamura Y, Enomoto N. et al. Usual interstitial pneumonia preceding collagen vascular disease: a retrospective case control study of patients initially diagnosed with idiopathic pulmonary fibrosis. PLoS One 2014; 9 (04) e94775
  • 5 Romagnoli M, Nannini C, Piciucchi S. et al. Idiopathic nonspecific interstitial pneumonia: an interstitial lung disease associated with autoimmune disorders?. Eur Respir J 2011; 38 (02) 384-391
  • 6 Sato T, Fujita J, Yamadori I. et al. Non-specific interstitial pneumonia; as the first clinical presentation of various collagen vascular disorders. Rheumatol Int 2006; 26 (06) 551-555
  • 7 Hu Y, Wang LS, Wei YR. et al. Clinical characteristics of connective tissue disease-associated interstitial lung disease in 1,044 Chinese patients. Chest 2016; 149 (01) 201-208
  • 8 Cottin V. Significance of connective tissue diseases features in pulmonary fibrosis. Eur Respir Rev 2013; 22 (129) 273-280
  • 9 Cottin V. Interstitial lung disease: are we missing formes frustes of connective tissue disease?. Eur Respir J 2006; 28 (05) 893-896
  • 10 Chung JH, Cox CW, Montner SM. et al. CT features of the usual interstitial pneumonia pattern: differentiating connective tissue disease-associated interstitial lung disease from idiopathic pulmonary fibrosis. AJR Am J Roentgenol 2018; 210 (02) 307-313
  • 11 Subhash HS, Ashwin I, Solomon SK, David T, Cherian AM, Thomas K. A comparative study on idiopathic pulmonary fibrosis and secondary diffuse parenchymal lung disease. Indian J Med Sci 2004; 58 (05) 185-190
  • 12 Jindal SK, Malik SK, Deodhar SD, Sharma BK. Fibrosing alveolitis: a report of 61 cases seen over the past five years. Indian J Chest Dis Allied Sci 1979; 21 (04) 174-179
  • 13 Sen T, Udwadia ZF. Retrospective study of interstitial lung disease in a tertiary care centre in India. Indian J Chest Dis Allied Sci 2010; 52 (04) 207-211
  • 14 Kundu S, Mitra S, Ganguly J, Mukherjee S, Ray S, Mitra R. Spectrum of diffuse parenchymal lung diseases with special reference to idiopathic pulmonary fibrosis and connective tissue disease: an eastern India experience. Lung India 2014; 31 (04) 354-360
  • 15 Maheshwari U, Gupta D, Aggarwal AN, Jindal SK. Spectrum and diagnosis of idiopathic pulmonary fibrosis. Indian J Chest Dis Allied Sci 2004; 46 (01) 23-26
  • 16 Sharma SK, Pande JN, Verma K, Guleria JS. Bronchoalveolar lavage fluid (BALF) analysis in interstitial lung diseases–a 7-year experience. Indian J Chest Dis Allied Sci 1989; 31 (03) 187-196
  • 17 Singh S, Collins BF, Sharma BB. et al. Interstitial lung disease in India. Results of a prospective registry. Am J Respir Crit Care Med 2017; 195 (06) 801-813
  • 18 Kim EA, Lee KS, Johkoh T. et al. Interstitial lung diseases associated with collagen vascular diseases: radiologic and histopathologic findings. Radiographics 2002; 22(Spec No):S151–S165. Erratum in: Radiographics 2003;23(5):1340
  • 19 Corte TJ, Copley SJ, Desai SR. et al. Significance of connective tissue disease features in idiopathic interstitial pneumonia. Eur Respir J 2012; 39 (03) 661-668
  • 20 Kligerman SJ, Groshong S, Brown KK, Lynch DA. Nonspecific interstitial pneumonia: radiologic, clinical, and pathologic considerations. Radiographics 2009; 29 (01) 73-87