A Multidisciplinary Evaluation Helps Identify the Antisynthetase Syndrome in Patients Presenting as Idiopathic Interstitial Pneumonia.

INTRODUCTION: Interstitial lung disease (ILD) is 1 possible manifestation of the idiopathic inflammatory myopathies (IIM). Occasionally, patients presenting with ILD are mistakenly diagnosed with idiopathic interstitial pneumonia (IIP), but after multidisciplinary evaluation, their ILD is determined to be because of antisynthetase syndrome (SynS) or myositis spectrum of disease. METHODS: We used retrospective analytic methods to identify patients with ILD evaluated at the National Jewish Health between February 2008 and August 2014 and believed initially to have IIP but ultimately diagnosed with SynS or myositis spectrum of disease. RESULTS: The cohort included 33 patients; most were white women with a mean age at presentation of 55 years. Their pulmonary physiologic impairment was moderate. In 31 cases, the ILD pattern by thoracic high-resolution computed tomography scan was nonspecific interstitial pneumonia (NSIP), organizing pneumonia (OP), or a combination of the 2. Surgical lung biopsy was performed in 21 patients; NSIP was the most common pattern. Less than one-third of the cohort had positive antinuclear antibodies. Two-thirds had positive SSA. All patients had either myositis-specific or myositis-associated autoantibody. Most had subtle extrathoracic symptoms or signs of SynS; 12 had an elevated serum creatine phosphokinase, but none had clinical evidence of myositis. None met the Peter and Bohan classification criteria for polymyositis/dermatomyositis. CONCLUSION: Among patients who present with presumed IIP, a multidisciplinary evaluation that includes the integration of clinical evaluations by rheumatologists and pulmonologists, morphologic (both histopathologic and radiographic) data, and serologic features is helpful in the detection of occult SynS or the myositis spectrum of disease.

Rituximab for the treatment of connective tissue disease-associated interstitial lung disease.

OBJECTIVE: To describe our experience with rituximab (RTX) as treatment for a diverse spectrum of chronic connective tissue disease-associated interstitial lung disease (CTD-ILD). METHODS: Twenty-four subjects with CTD-ILD were included. All had pulmonary function testing before and after their first RTX infusion. Each subject was evaluated in a multidisciplinary autoimmune and ILD outpatient clinic. Data were extracted by retrospective review of complete medical records. RESULTS: Most subjects were middle-aged white women with rheumatoid arthritis (RA) (n=15) and a nonspecific interstitial pneumonia (NSIP) pattern on high-resolution chest computed tomography scans (n=17). Sixteen subjects received a corticosteroid-sparing agent at the time of RTX initiation; mostly mycophenolate mofetil (n=8). RTX administration was not associated with corticosteroid-sparing effects: 13 subjects were on prednisone at the time of the initial RTX cycle, and 9 remained on prednisone at 6 months after (mean daily dosage 10.2±16.2 mg before vs. 5.6±11.0 mg after, p=0.27). RTX had no appreciable effect on pulmonary physiology; however, individual trajectories for percentage predicted forced vital capacity (FVC%) were highly variable. The underlying CTD (RA vs. non-RA) and ILD pattern did not appear to affect response to RTX. Among 14 subjects who received multiple RTX cycles, FVC% trajectories were variable: FVC% increased in eight and declined in six. Respiratory infections were the most common post-RTX adverse event. CONCLUSION: In this small, retrospective study of chronic CTD-ILD, RTX was not associated with changes in FVC% or corticosteroid-sparing effects. Controlled, prospective studies are needed to more confidently define the effects of RTX in CTD-ILD.