Clinical features and natural history of interstitial pneumonia with autoimmune features: A single center experience.
To describe the clinical phenotype and natural history of a cohort of patients with interstitial pneumonia with autoimmune features (IPAF).



A retrospective, single center study of 56 patients with IPAF evaluated between February 2008 and August 2014. All clinical data were extracted from the electronic medical record and longitudinal changes in forced vital capacity (FVC) were analyzed with mixed-effects, piecewise linear regression models that considered time as a continuous factor.



All patients fulfilled classification criteria for IPAF. The majority were women (71%) and never smokers (68%). The most frequently identified clinical features were Raynaud's phenomenon (39%), distal digital fissuring (29%), Gottron's sign (18%) and inflammatory arthropathy (16%). The most frequently identified serologies were antinuclear antibody (ANA) (48%), anti-Ro (SSA) (43%) and anti-tRNA-synthetase antibodies (36%). Nonspecific interstitial pneumonia (NSIP) (57.1%) followed by NSIP with organizing pneumonia (18%) were the most common radiologic patterns, while usual interstitial pneumonia was identified in only 9%. All but one patient was treated with immunosuppression: prednisone (82%) and mycophenolate mofetil (76%) were the most frequently used agents. During a follow-up period of 284.9 ± 141.3 days, modeled longitudinal FVC% was stable (slope = 0.69/year) and no deaths were observed in the cohort.



In this single center study, patients with IPAF were predominately non-smoking women with high-resolution computed tomography scans that suggested NSIP. Their pulmonary physiology was stable, and during limited follow-up, no deaths were observed. Prospective and multi-center studies are needed to better inform our understanding of IPAF.
Department of Medicine, Hôpital Maisonneuve-Rosemont affiliated to Université de Montréal, Montréal, Québec, Canada.
Sandra
S
Chartrand
Department of Medicine, National Jewish Health, Denver, CO, USA; Department of Medicine, University of Colorado School of Medicine, Aurora, CO, USA.
Jeffrey J
JJ
Swigris
Department of Medicine, University of Colorado School of Medicine, Aurora, CO, USA.
Lina
L
Stanchev
Department of Medicine, University of Colorado School of Medicine, Aurora, CO, USA.
Joyce S
JS
Lee
Department of Medicine, National Jewish Health, Denver, CO, USA; Department of Medicine, University of Colorado School of Medicine, Aurora, CO, USA.
Kevin K
KK
Brown
Department of Medicine, University of Colorado School of Medicine, Aurora, CO, USA. Electronic address: aryeh.fischer@ucdenver.edu.
Aryeh
A
Fischer
D000305:Adrenal Cortex Hormones / Q000627:therapeutic use; D000328:Adult; D000604:Amino Acyl-tRNA Synthetases / Q000037:antagonists & inhibitors* / Q000276:immunology; D000974:Antibodies, Antinuclear; D001327:Autoimmune Diseases / Q000175:diagnosis / Q000276:immunology; D001706:Biopsy; D002248:Carbon Monoxide / Q000378:metabolism; D003240:Connective Tissue Diseases / Q000175:diagnosis / Q000473:pathology; D003937:Diagnosis, Differential; D004791:Enzyme Inhibitors / Q000627:therapeutic use; D005260:Female; D006801:Humans; D054988:Idiopathic Interstitial Pneumonias / Q000175:diagnosis / Q000473:pathology; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D008168:Lung / Q000000981:diagnostic imaging* / Q000473:pathology / Q000503:physiopathology; D017563:Lung Diseases, Interstitial / Q000175:diagnosis* / Q000188:drug therapy / Q000473:pathology / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D009173:Mycophenolic Acid / Q000627:therapeutic use; D010641:Phenotype; D011653:Pulmonary Diffusing Capacity / Q000502:physiology; D012129:Respiratory Function Tests / Q000379:methods; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed; D014797:Vital Capacity / Q000502:physiology
D000305:Adrenal Cortex Hormones; D000974:Antibodies, Antinuclear; D004791:Enzyme Inhibitors; D007166:Immunosuppressive Agents; D002248:Carbon Monoxide; D000604:Amino Acyl-tRNA Synthetases; D009173:Mycophenolic Acid
Connective tissue disease; Idiopathic interstitial pneumonia; Interstitial lung disease; Interstitial pneumonia with autoimmune features