A 61-year-old man comes to the emergency department due to 3 weeks of cough with blood-tinged sputum and shortness of breath. He has also felt more fatigued and reports weight loss during this period. Medical history is significant for Hodgkin lymphoma treated successfully with radiation and chemotherapy 20 years ago. The patient works as a medical assistant at a public health community clinic for underserved patients. Temperature is 37.2 C (99 F), blood pressure is 113/76 mm Hg, and pulse is 88/min. Oxygen saturation is 96% on room air. Laboratory studies reveal a leukocyte count of 7,000/mm3. Chest x-ray is shown in the image below:
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Which of the following is the best initial step in management of this patient?
Airborne precautions | |
Indications |
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Components |
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*Only when uncrusted lesions are present; contact precautions also required. | |
This patient with subacute cough and constitutional symptoms (weight loss, fatigue) has a cavitary pulmonary lesion with surrounding consolidation. Although these manifestations can be seen in aspiration pneumonia, fungal pulmonary infection, or malignancy, this patient's employment at a public health community clinic and immunosuppression (eg, history of prior malignancy) put him at risk for pulmonary tuberculosis (TB).
TB is transmissible through microscopic particles that remain suspended in air; risk factors for transmission include cough and cavitary lung disease. Therefore, any patient with suspected TB should immediately be placed on airborne precautions (ie, respiratory isolation) while diagnostic testing is undertaken. Recommended measures include placement in a negative pressure room, use of disposable N95 respirators by health care workers, and use of a surgical mask by the patient to reduce droplet production. If a negative pressure room is not immediately available, the patient should wear a surgical mask and be moved to a private area.
(Choice A) This patient's history of Hodgkin lymphoma treated with chemotherapy and radiation therapy increases the risk for secondary malignancy (eg, lung cancer); this possibility should be explored if infectious work-up is negative. In this patient with TB risk factors, respiratory isolation should be initiated prior to diagnostic work-up.
(Choice B) In general, the diagnosis of pulmonary TB should be confirmed (eg, detection of acid-fast bacilli in sputum) prior to initiating antibiotic treatment. Treatment typically consists of an oral, not intravenous, regimen of 4 drugs.
(Choice D) Serology can be used in diagnosing certain lung infections; for example, positive Aspergillus IgG antibodies are found in chronic cavitary pulmonary aspergillosis, which can cause a cavitary lung lesion and hemoptysis. Because of this patient's TB risk factors, respiratory isolation should be initiated first.
(Choice E) A swallowing evaluation may be appropriate for patients with suspected lung abscess due to aspiration. However, this patient lacks typical risk factors (eg, swallowing difficulties, prior stroke, alcohol use disorder) and history (eg, altered sensorium, seizures). Respiratory isolation and diagnostic work-up for TB should be initiated first.
Educational objective:
The diagnosis of pulmonary tuberculosis (TB) should be suspected in patients with risk factors (eg, immunosuppression, exposure to medically underserved populations) and associated radiographic findings (eg, upper lobe cavitary lesions). TB is highly transmissible through microscopic airborne particles; therefore, patients with suspected TB should immediately be placed on airborne precautions (eg, negative pressure isolation, use of N95 masks) while confirmatory testing is pursued.