Lung-dominant connective tissue disease among patients with interstitial lung disease: prevalence, functional stability, and common extrathoracic features

Abstract

OBJECTIVE: To describe the characteristics of a cohort of patients with lung-dominant connective tissue disease (LD-CTD). METHODS: This was a retrospective study of patients with interstitial lung disease (ILD), positive antinuclear antibody (ANA) results (≥ 1/320), with or without specific autoantibodies, and at least one clinical feature suggestive of connective tissue disease (CTD). RESULTS: Of the 1,998 patients screened, 52 initially met the criteria for a diagnosis of LD-CTD: 37% were male; the mean age at diagnosis was 56 years; and the median follow-up period was 48 months. During follow-up, 8 patients met the criteria for a definitive diagnosis of a CTD. The remaining 44 patients comprised the LD-CTD group, in which the most prevalent extrathoracic features were arthralgia, gastroesophageal reflux disease, and Raynaud's phenomenon. The most prevalent autoantibodies in this group were ANA (89%) and anti-SSA (anti-Ro, 27%). The mean baseline and final FVC was 69.5% and 74.0% of the predicted values, respectively (p > 0.05). Nonspecific interstitial pneumonia and usual interstitial pneumonia patterns were found in 45% and 9% of HRCT scans, respectively; 36% of the scans were unclassifiable. A similar prevalence was noted in histological samples. Diffuse esophageal dilatation was identified in 52% of HRCT scans. Nailfold capillaroscopy was performed in 22 patients; 17 showed a scleroderma pattern. CONCLUSIONS: In our LD-CTD group, there was predominance of females and the patients showed mild spirometric abnormalities at diagnosis, with differing underlying ILD patterns that were mostly unclassifiable on HRCT and by histology. We found functional stability on follow-up. Esophageal dilatation on HRCT and scleroderma pattern on nailfold capillaroscopy were frequent findings and might come to serve as diagnostic criteria.

Serological and morphological prognostic factors in patients with interstitial pneumonia with autoimmune features

“…These reports suggest that some patients presented with ILD before being diagnosed with CTD. Pereira DA et al reported that amoung 52 patients with lung-dominant CTD, 8 developed CTD later during the median follow up of 48 months [ 28 ]. In contrast, Chartrand et al reported that amoung 56 patients with IPAF, none developed CTD later during the median follow up of 284.9 weeks [ 29 ].…”

Idiopathic and immune‐related pulmonary fibrosis: diagnostic and therapeutic challenges

“…Many guidelines recommended testing for a narrow panel of autoantibodies only, with additional testing performed according to relevant clinical signs and symptoms suggestive of an underlying CTD . ILD may be associated with all CTDs, and whilst this is most commonly seen in established CTD, patients may present with ILD as the initial feature of their CTD prior to subsequent development of other CTD clinical features, or may present with isolated ILD as the sole clinical manifestation of a CTD . Detection of autoantibodies may reveal previous undiagnosed CTD in patients, even when seen in specialist ILD clinics, and restricting serological testing according to clinical features will inadvertently miss patients with CTD‐ILD .…”

“…4 ILD may be associated with all CTDs, and whilst this is most commonly seen in established CTD, patients may present with ILD as the initial feature of their CTD prior to subsequent development of other CTD clinical features, or may present with isolated ILD as the sole clinical manifestation of a CTD. 25,26 Detection of autoantibodies may reveal previous undiagnosed CTD in patients, even when seen in specialist ILD clinics, and restricting serological testing according to clinical features will inadvertently miss patients with CTD-ILD. 27 In a recent study of 80 undifferentiated ILD patients where retrospective autoantibody testing was performed to a comprehensive autoantibody panel, the ILD diagnosis was able to be reclassified in 6 of 80 (7.5%) cases to CTD-ILD.…”

Morphologic Aspects of Interstitial Pneumonia With Autoimmune Features

“…23 A study to characterize patients with LD-CTD demonstrated that NSIP was the most common morphologic pattern observed on HRCT (45%) and surgical lung biopsy (27%), and 15% of those patients prospectively met the criteria for a definitive diagnosis of a CTD. 24 In 2007, Kinder et al 10 proposed that idiopathic NSIP is a manifestation of UCTD. In this study, among 18 patients classified as UCTD who underwent surgical pulmonary biopsy, 15 showed an NSIP pattern, in contrast to only 2 patients in the control group that was categorized as idiopathic interstitial pneumonia.…”