A 48-year-old man comes to the office due to progressive weakness for the past 2 months. The patient has experienced difficulty climbing stairs, especially when carrying heavy items such as groceries, and his symptoms have become progressively worse. He also reports occasional fevers, but no significant pain in the muscles or joints. The patient has had no diplopia, dyspnea, dysphagia, abdominal pain, or heat or cold intolerance. He has a history of hypertension and hyperlipidemia, for which he has taken losartan and atorvastatin, respectively, for the last 4 years. The patient does not use tobacco, alcohol, or illicit drugs. Temperature is 37.1 C (98.8 F), blood pressure is 132/84 mm Hg, pulse is 72/min, and respirations are 14/min. He has no scleral icterus. Cardiopulmonary examination is normal. The abdomen is soft and nontender with no hepatosplenomegaly. Muscle strength is 3/5 in the deltoids and hip flexors but is otherwise normal. Deep tendon reflexes are normal and symmetric, and sensations to pain and light touch are intact. There is mild muscle tenderness and some of the small joints of both hands are tender to palpation without any swelling or erythema. He has no skin rash. Laboratory results are as follows:
After confirmation of the diagnosis, the patient is started on appropriate therapy. During a follow-up visit 6 months later, he says the muscle weakness has improved but he becomes breathless on moderate exertion. The patient has to stop to catch his breath when walking 3 blocks to his office, which he had previously been able to do without stopping. He has also had a mild nonproductive cough. Temperature is 36.6 C (98 F), blood pressure is 130/80 mm Hg, pulse is 82/min, and respirations are 16/min. The neck veins are flat. Heart sounds are normal, but lung auscultation reveals bibasilar fine crackles. Muscle strength is normal. Blood cell counts and serum chemistry are within normal limits. Chest radiograph is normal. Which of the following is the best next step in management of this patient?

Question

A 48-year-old man comes to the office due to progressive weakness for the past 2 months.  The patient has experienced difficulty climbing stairs, especially when carrying heavy items such as groceries, and his symptoms have become progressively worse.  He also reports occasional fevers, but no significant pain in the muscles or joints.  The patient has had no diplopia, dyspnea, dysphagia, abdominal pain, or heat or cold intolerance.  He has a history of hypertension and hyperlipidemia, for which he has taken losartan and atorvastatin, respectively, for the last 4 years.  The patient does not use tobacco, alcohol, or illicit drugs.  Temperature is 37.1 C (98.8 F), blood pressure is 132/84 mm Hg, pulse is 72/min, and respirations are 14/min.  He has no scleral icterus.  Cardiopulmonary examination is normal.  The abdomen is soft and nontender with no hepatosplenomegaly.  Muscle strength is 3/5 in the deltoids and hip flexors but is otherwise normal.  Deep tendon reflexes are normal and symmetric, and sensations to pain and light touch are intact.  There is mild muscle tenderness and some of the small joints of both hands are tender to palpation without any swelling or erythema.  He has no skin rash.  Laboratory results are as follows:
 After confirmation of the diagnosis, the patient is started on appropriate therapy.  During a follow-up visit 6 months later, he says the muscle weakness has improved but he becomes breathless on moderate exertion.  The patient has to stop to catch his breath when walking 3 blocks to his office, which he had previously been able to do without stopping.  He has also had a mild nonproductive cough.  Temperature is 36.6 C (98 F), blood pressure is 130/80 mm Hg, pulse is 82/min, and respirations are 16/min.  The neck veins are flat.  Heart sounds are normal, but lung auscultation reveals bibasilar fine crackles.  Muscle strength is normal.  Blood cell counts and serum chemistry are within normal limits.  Chest radiograph is normal.  Which of the following is the best next step in management of this patient?

Quizplus · Accepted Answer

Explanation: 11ec2b69_c0bc_2a1e_8f63_117984411159_MD0005_00 Polymyositis is treated with systemic glucocorticoids, often with corticosteroid-sparing agents (eg, methotrexate, azathioprine). This patient has had a good response, with improved muscle strength and normalization of muscle enzymes and inflammatory markers. However, patients with polymyositis can also develop a number of pulmonary complications, including interstitial lung disease (ILD), infection (due to immune suppressive therapy), drug-induced pneumonitis (eg, methotrexate pneumonitis), and respiratory muscle weakness. ILD is especially common in patients with a positive anti-Jo-1 antibody, and can be identified on high-resolution CT imaging as ground-glass opacities, reticular changes, honeycombing, or patchy consolidation. Pulmonary function tests (PFTs) should be performed to distinguish ILD from respiratory muscle weakness and will show decreased forced vital capacity, total lung capacity, and diffusing capacity. Initial management of ILD in patients with polymyositis is similar to treatment of the underlying polymyositis with systemic glucocorticoids and corticosteroid-sparing agents, but ILD may progress despite improvement in myopathic features. (Choice A) Bronchoscopy with transbronchial biopsy or bronchoalveolar lavage may be needed to diagnose ILD in patients who do not have characteristic findings on CT imaging and PFTs. However, CT and PFTs are usually performed first. (Choice B) Myocarditis with conduction system disease and congestive heart failure is a potential complication of polymyositis. However, this patient does not have any suggestive findings such as jugular venous distension, wet crackles, or signs of pulmonary edema on chest x-ray. (Choice D) Serum IgE levels are nonspecific, and can be elevated in a variety of allergic and inflammatory conditions. IgE levels are commonly used in the evaluation of allergic bronchopulmonary aspergillosis, but these patients typically have underlying progressive asthma with recurrent exacerbations and infiltrates on chest x-ray. (Choice E) Ventilation/perfusion scan is useful in diagnosis of pulmonary embolism, which would usually present with acute dyspnea, tachycardia, and hypoxemia. This patient does not have typical features and has low probability for pulmonary embolism; to exclude pulmonary embolism, a D-dimer could be considered for risk stratification prior to imaging. Educational objective: Patients with polymyositis can develop pulmonary complications, including interstitial lung disease, infection, drug-induced pneumonitis, and respiratory muscle weakness. Interstitial lung disease can be identified on high-resolution CT imaging as ground-glass opacities, reticular changes, honeycombing, or patchy consolidation. Pulmonary function tests show decreased forced vital capacity, total lung capacity, and diffusing capacity.

A 48-Year-Old Man Comes to the Office Due to Progressive