A 76-year-old man comes to the office due to nonproductive cough and progressive shortness of breath on exertion for the past 6 months. He uses 2 pillows at night to sleep and occasionally wakes up to urinate. The patient has had no chest pain, weight loss, night sweats, or joint pains. Two months ago, another physician started him on furosemide, which has provided little symptomatic relief. Other medical conditions include hypertension and hypercholesterolemia. The patient is an ex-smoker with a 40-pack-year history; he quit 10 years ago. He used to play golf regularly but stopped 3 months ago because he felt too winded.
Blood pressure is 144/78 mm Hg and pulse is 89/min and regular. Oxygen saturation is 93% on room air. BMI is 30 kg/m². Jugular venous pressure is estimated at 10 cm H₂O. Bibasilar crackles are heard on lung auscultation. The apical impulse is not displaced. A faint holosystolic murmur is heard at the lower sternum and increases with inspiration. The abdomen is soft and nontender. Liver span is 11 cm and there is no splenomegaly. Digital clubbing and trace ankle edema are present.
ECG shows normal sinus rhythm and nonspecific T-wave changes. Chest x-ray reveals prominent interstitial markings and decreased lung volumes.
Which of the following is most likely to establish this patient's diagnosis?

Question

Quizplus · Accepted Answer

Idiopathic pulmonary fibrosis (IPF) is the most common type of interstitial lung disease. Patients are typically age 50-70 with progressive dyspnea on exertion and chronic dry cough that disturbs their daily activities. Approximately 50% of patients with IPF have a significant smoking history. Examination usually reveals clubbing (50% of patients) and early inspiratory crackles, predominantly in the lower posterior lung zones. Chest x-ray characteristically reveals decreased lung volumes and interstitial opacities. This patient's clinical presentation is consistent with IPF complicated by pulmonary hypertension (suggested by tricuspid regurgitation murmur) and right-sided heart failure (suggested by jugular venous distension and ankle edema). The next step is high-resolution chest CT scan (HRCT), which usually shows honeycombing, cystic changes, and traction bronchiectasis (especially at the bases and in subpleural areas). Patients with classic HRCT findings can be diagnosed with IPF without further testing; however, those with inconclusive noninvasive testing may require lung biopsy. high-resolution chest CT scan (Choice A) Bronchoscopy with transbronchial biopsy is unreliable in diagnosing interstitial lung diseases due to inadequate size of the pathologic sample. When biopsy is needed, video-assisted thorascopic biopsy is typically preferred. (Choice B) Exercise stress testing is indicated to risk-stratify coronary artery disease, which is not associated with the clubbing seen in this patient. (Choice D) Transesophageal echocardiogram with bubble study is useful to rule out atrial septal defect, which can present with right-sided heart failure and clubbing if severe pulmonary hypertension develops. However, an unremarkable chest x-ray would be expected as would the absence of crackles on lung examination. (Choice E) Transthoracic echocardiogram (TTE) is appropriate for evaluating left-sided heart failure; however, the nondisplaced apical impulse and minimal symptomatic improvement with furosemide make left-sided heart failure less likely. In addition, left-sided heart failure would not explain the decreased lung volumes on chest x-ray. Although TTE is also appropriate to evaluate this patient's suspected pulmonary hypertension and right-sided heart failure, it would not establish the most likely underlying diagnosis of IPF. Educational objective: Idiopathic pulmonary fibrosis is the most common type of interstitial lung disease. It typically presents with nonproductive cough and progressive shortness of breath, and may lead to pulmonary hypertension and right-sided heart failure. High-resolution chest CT scan is the preferred test for diagnosis. __________ References: Workshop on idiopathic pulmonary fibrosis in older adults. (http://www.ncbi.nlm.nih.gov/pubmed/20822991) Idiopathic pulmonary fibrosis. (http://www.ncbi.nlm.nih.gov/pubmed/18366757)

A 76-Year-Old Man Comes to the Office Due to Nonproductive