The approach to chronic dyspnea in CTDs. CXR Chest X-ray, CTD Connective tissue disease, C-P Costo-phrenic angle, Dx Diagnostic, Rx Therapeutic, Bx Biopsy, GGO Ground glass opacity, HRCT High resolution computed tomography, PFT Pulmonary function test, ILD Interstitial lung disease, NSIP Non-specific interstitial pneumonia, OP Organizing pneumonia, UIP Usual interstitial pneumonia, OB Obliterative bronchiolitis, DLco Diffusion Lung capacity for carbon monoxide, DL/VA Diffusion per unit area of alveolar volume, MIP Maximum inspiratory pressure, MEP Maximum expiratory pressure, VC Vital capacity, FVC Forced vital capacity, EMG Electromyogram, SLS Shrinking lung syndrome, PASP Pulmonary artery systolic pressure, TR Tricuspid regurge, RHC Right heart catheterization, PAP Pulmonary artery pressure, PCWP Pulmonary capillary wedge pressure, R/o Role out, PH Pulmonary hypertension, PCP Pneumocystis pneumonia, CMV Cytomegalovirus, HSV Herpes simplex virus, TB Tuberculosis, LDH Lactate dehydrogenase, RF Rheumatoid factor, RBC Red blood cell, Anti-nuclear antibody