ABSTRACT
BACKGROUND: We proposed the term "UIPAF" to define patients with Usual Interstitial Pneumonia (UIP) associated with only one domain of the classification called "Interstitial Pneumonia with Autoimmune Features" (IPAF). The objective of this study was to evaluate the clinical presentation and prognosis of UIPAF patients, compared with two cohorts, composed of IPAF and idiopathic pulmonary fibrosis (IPF) patients, respectively. METHODS: The patients were enrolled as IPAF, UIPAF, or IPF based on clinical, serological, and radiological data and evaluated by a multidisciplinary team. RESULTS: We enrolled 110 patients with IPF, 69 UIPAF, and 123 IPAF subjects. UIPAF patients were similar to IPAF regarding autoimmune features, except for the prevalence of Rheumatoid Factor in UIPAF and anti-SSA in IPAF. A similar proportion of the two cohorts progressed toward a specific autoimmune disease (SAD), with differences in the kind of SAD developed. The real-life management and prognosis of UIPAF patients proved to be almost identical to IPF. CONCLUSIONS: UIPAF shared with IPAF similar autoimmune features, suggesting the opportunity to be considered IPAF, excluding the morphological domain by the classification. However, the real-life management and prognosis of UIPAF are similar to IPF. These data suggest a possible modification in the therapeutic management of UIPAF.
ABSTRACT
Mixed Connective Tissue Disease (MCTD) is an autoimmune disease first described by Sharp et al in 1972, characterized by the presence of anti-Ribonucleoprotein antibodies directed against the U1 complex (anti-U1RNP). The condition shares clinical characteristics with Systemic Lupus Erythematosus, Rheumatoid Arthritis, and Systemic Sclerosis. Diagnosis is quite difficult due to its rarity, the lack of validated classification criteria, and its heterogeneous clinical presentation. While in the early stages its nuanced clinical features might lead to it being incorrectly classified as other Connective Tissue Diseases (CTDs) or even not recognized, in cases of longstanding disease its classification as a CTD is clear but challenging to discriminate from overlap syndromes. MCTD should be considered a distinct entity due to the presence of a specific genetic substrate and the presence of the high titer of a specific autoantibody, anti-U1RNP, present in all the commercial kits for Extractable Nuclear Antigens, and almost always associated with Antinuclear Antibody positivity with a coarse speckled pattern. Except for anti-U1RNP, no specific biomarkers are available to guide clinicians to a correct classification of MCTD, which is arrived at by the association of clinical, serological and instrumental evaluation. In the first stages, the disease is mainly characterized by Raynaud's phenomenon, inflammatory arthritis, puffy fingers, myalgia and/or myositis, and rarely, trigeminal neuropathy. Longstanding disease is generally associated with the development of Pulmonary Hypertension and Interstitial Lung Disease, which are the two main causes of mortality in MCTD. The aim of this review is to summarize current knowledge on the early recognition of MCTD.
ABSTRACT
In this study, it was found that myositis-specific and myositis-associated antibodies (MSAs and MAAs) improved the recognition of idiopathic inflammatory myopathies (IIMs) in interstitial lung disease (ILD) patients. The objective of this study is to propose a clinical method to evaluate myalgia in respiratory settings as a possible tool for the recognition of MSA/MAA positivity in ILD patients. We prospectively enrolled 167 ILD patients with suspected myositis, of which 63 had myalgia evoked at specific points (M+ILD+). We also enrolled in a 174 patients with only myalgia (M+ILD-) in a rheumatological setting. The patients were assessed jointly by rheumatologists and pulmonologists and were tested for autoantibodies. M+ILD+ patients were positive for at least one MAA/MSA in 68.3% of cases, as were M-ILD+ patients in 48.1% of cases and M+ILD- patients in 17.2% of cases (p = 0.01 and <0.0001, respectively). A diagnosis of IIM was made in 39.7% of M+ILD+ patients and in 23.1% of the M-ILD+ group (p = 0.02). Myalgia was significantly associated with positivity for MSA/MAAs in ILD patients (p = 0.01, X2: 6.47). In conclusion, myalgia in ILD patients with suspected myositis is associated with MSA/MAA positivity, and could support a diagnosis of IIM. A significant proportion of M+ILD- patients also had MSA/MAA positivity, a phenomenon warranting further study to evaluate its clinical meaning.
