A 58-year-old man comes to the office due to exertional dyspnea and cough. His symptoms started 6 months ago and have progressively worsened. Other medical problems include recurrent pyelonephritis, peptic ulcer disease, and rheumatoid arthritis. The patient had taken a medication for rheumatoid arthritis for many years but stopped a year ago, as the drug failed to improve his worsening hand arthritis. He does not use tobacco, alcohol, or illicit drugs. Physical examination shows joint disease consistent with rheumatoid arthritis. Chest x-ray is shown in the image below. Which of the following is the most likely explanation for this patient's pulmonary symptoms?

Question

A 58-year-old man comes to the office due to exertional dyspnea and cough.  His symptoms started 6 months ago and have progressively worsened.  Other medical problems include recurrent pyelonephritis, peptic ulcer disease, and rheumatoid arthritis.  The patient had taken a medication for rheumatoid arthritis for many years but stopped a year ago, as the drug failed to improve his worsening hand arthritis.  He does not use tobacco, alcohol, or illicit drugs.  Physical examination shows joint disease consistent with rheumatoid arthritis.  Chest x-ray is shown in the image below.  Which of the following is the most likely explanation for this patient's pulmonary symptoms?

Quizplus · Accepted Answer

11ec160b_3a11_5b63_9249_2d690b02e7fa_MD0001_00 As compared to normal imaging, this patient's chest x-ray shows a bilateral and diffuse pattern of small, irregular (reticulonodular) opacities that are most pronounced in the lower lobes. These findings are most consistent with pulmonary fibrosis, which typically manifests with gradual-onset progressive dyspnea, nonproductive cough, fatigue, and eventual weight loss and failure to thrive. Auscultation may reveal end-inspiratory crackles at the lung bases. Pulmonary function tests show a restrictive pattern with decreased lung volumes, decreased FEV1 and FVC levels, a normal or increased FEV1/FVC ratio, and decreased diffusion capacity of carbon monoxide. Microscopically, progressive fibrosis can lead to cystically dilated bronchioles that later coalesce to form the honeycomb appearance found in advanced disease. Rheumatoid arthritis (RA) can cause a variety of pulmonary manifestations; the most common is a form of interstitial lung disease similar to idiopathic interstitial pneumonia. In addition, multiple agents used to treat RA (eg, methotrexate, cyclophosphamide, sulfasalazine) can cause fibrotic lung disease. (Choice A) Atelectasis refers to diminished air volume in part of the lung and most commonly occurs due to obstruction of the corresponding bronchus or bronchiole. Chest x-ray shows opacification (collapse) of the corresponding lobe/lobule. (Choice B) Chest x-ray in decompensated left ventricular failure shows cardiomegaly (heart >1 hemithorax in size), pulmonary edema, pleural effusions, and enlarged pulmonary vessels. (Choice C) Obstructive pulmonary diseases (eg, asthma, chronic obstructive pulmonary disease) are associated with lung hyperinflation on chest x-ray. This patient has mild hyperinflation (likely due to a deep inspiration during imaging) however the diaphragms are not markedly flattened. In addition, reticulonodular opacities are not seen in these conditions. (Choice E) Chest x-ray in pulmonary hypertension shows enlargement of the pulmonary arteries and the right ventricle. Educational objective: Pulmonary fibrosis presents with gradual-onset progressive dyspnea, nonproductive cough, fatigue, eventual weight loss, and bilateral reticulonodular opacities on chest x-ray. Pulmonary function tests reveal a restrictive pattern. Patients with rheumatoid arthritis can develop interstitial lung diseases, both from the pulmonary manifestations of the disease itself and from certain therapies (eg, methotrexate, cyclophosphamide, sulfasalazine). __________ References: The lung in rheumatoid arthritis. (http://www.ncbi.nlm.nih.gov/pubmed/21196098)

A 58-Year-Old Man Comes to the Office Due to Exertional