Chest
CommentaryConnective Tissue Disease-Associated Interstitial Lung Disease: A Call for Clarification
Section snippets
Implications of the Diagnosis
In our opinion, numerous implications of identifying underlying systemic autoimmune disease in patients presenting with an IP exist. Most significantly, CTD-IP is associated with a more favorable prognosis than IIP.1 Although it is not known whether the identification of occult forms of CTD carries a similarly more-favorable prognosis, it can be argued that future decisions that incorporate the knowledge of underlying autoimmunity might well promote an improved understanding of pathogenesis and
Challenges and Limitations
Although all pulmonologists see patients in whom they suspect an underlying autoimmune mechanism as the cause of the pulmonary disease, confirming systemic autoimmune disease and diagnosing specific CTDs in the absence of classic clinical findings are challenging,2, 3 and we believe that current screening strategies are largely inadequate. Detecting CTD by simply screening with nonspecific autoantibodies does not suffice,2, 3, 4, 5, 6 and current rheumatologic classification schemes are
Identifying Occult CTD
We believe that the detection of occult CTD in patients presenting with IP is optimized by multidisciplinary collaboration. Finding occult CTD is not uncommon. It has been estimated that among patients presenting with an apparently IIP, roughly 15% are found to have underlying CTD after more thorough evaluation.5 Homma and colleagues7 evaluated whether IP as the sole presentation of CTD can be differentiated from IIP. They described 68 patients who had presented with IIP and were followed
Redefining Undifferentiated CTD Is Problematic
The concept has been proposed that all patients with idiopathic NSIP, even those without extrathoracic features or serum autoantibodies, actually have an undifferentiated CTD (UCTD).13, 15 In our opinion, although this hypothesis is interesting, the revised application of this CTD diagnosis to encompass all NSIP cases is problematic. Redefining the UCTD diagnosis in this way requires input from rheumatologists who are generally skeptical about accepting IP as a diagnostic criterion for CTD. For
Some Proposed Solutions
In the face of the challenges posed by these disorders that fall short of universally acceptable diagnoses and of discordant perceptions about disease classification as well as the impasse in accepting the redefining of UCTD, we offer the following modest suggestions.
Conclusions
We believe that multidisciplinary collaboration in the evaluation of IP and testing the concept of lung-dominant CTD ultimately will allow more precise disease differentiation to be made and might lead to a better understanding of IP. In addition, it can be argued that future decisions that incorporate the knowledge of lung-dominant CTD might well lead to the development of more targeted therapies as well as affect treatment choices. Further research is needed to validate the proposed
Acknowledgments
Financial/nonfinancial disclosures: The authors have reported to CHEST that no potential conflicts of interest exist with any companies/organizations whose products or services may be discussed in this article.
References (17)
- et al.
Interstitial lung disease in the patient who has connective tissue disease
Clin Chest Med
(2004) - et al.
Ascertainment of collagen vascular disease in patients presenting with interstitial lung disease
Respir Med
(2009) - et al.
Anti-synthetase syndrome in ANA and anti-Jo-1 negative patients presenting with idiopathic interstitial pneumonia
Respir Med
(2009) - et al.
Unique characteristics of systemic sclerosis sine scleroderma-associated interstitial lung disease
Chest
(2006) - et al.
Pathologic and radiologic differences between idiopathic and collagen vascular disease-related usual interstitial pneumonia
Chest
(2009) - et al.
Idiopathic non-specific interstitial pneumonia: as an “autoimmune interstitial pneumonia”
Respir Med
(2005) - et al.
Prognosis of fibrotic interstitial pneumonia: idiopathic versus collagen vascular disease-related subtypes
Am J Respir Crit Care Med
(2007) Interstitial lung disease: are we missing formes frustes of connective tissue disease?
Eur Respir J
(2006)
Cited by (264)
Histopathological significance of connective tissue disease-associated interstitial lung disease in transbronchial lung cryobiopsy specimens
2024, Pathology Research and PracticeInterstitial pneumonia with autoimmune features: Aiming to define, refine, and treat
2023, Revista Colombiana de ReumatologiaInterstitial pneumonia with autoimmune features: Evaluation of connective tissue disease incidence during follow-up
2022, European Journal of Internal MedicineCitation Excerpt :In some cases, patients with ILD display clinical or serological autoimmune features but fail to meet current international CTD classification criteria. Various definitions have been used to describe these patients in the literature: “undifferentiated connective tissue disease-associated ILD”, “autoimmune-featured ILD” and “lung-dominant CTD” [12–14]. Recently, the European Respiratory Society/American Thoracic Society experts proposed a new classification, “interstitial pneumonia with autoimmune features” (IPAF) [15].
Interstitial pneumonia with autoimmune features
2022, Handbook of Systemic Autoimmune Diseases
Reproduction of this article is prohibited without written permission from the American College of Chest Physicians (http://www.chestpubs.org/site/misc/reprints.xhtml).