Review Question - QID 216286

This incarcerated patient presents with cough, fever, and night sweats with acute progression to respiratory distress (tachypnea, accessory respiratory muscle use, and oxygen desaturation) with diffuse infiltrates on chest radiograph concerning for a tuberculosis (TB) infection. In addition to prompt stabilization, patients with a suspicious history for active TB should be immediately put on airborne respiratory isolation precautions.

Transmission of pulmonary Mycobacterium tuberculosis occurs through inhalation of airborne bacilli. Those at highest risk of infection are individuals that reside in close quarters with others (e.g., prison, homeless shelters), have traveled or emigrated from TB endemic regions (e.g., Southeast Asia, Africa, South America), work in health care settings, or have a history of immunosuppression. Not all who are infected will progress to active disease, as an individual can either completely clear the infection or successfully contain the bacilli for decades in what is termed a latent TB infection. However, some individuals will progress after initial inoculation or secondary reactivation to active disease, which often presents with cough, hemoptysis, night sweats, weight loss, and fever. From a public health perspective, if a patient is suspected to have active TB they must be admitted under respiratory airborne precautions while they undergo further diagnosis and management.

Suarez et al. review the diagnosis and treatment of tuberculosis. They note that rapid and early diagnosis and treatment is necessary to improve outcomes. They recommend considering the diagnosis in patients presenting with unclear infectious or pulmonary symptoms as this diagnosis is often missed.

Figure/Illustration A shows a chest radiograph with uniformly distributed hazy opacities in all lung fields. In the context of this patient presentation, these features are highly suggestive of miliary TB, a disseminated form of the infection in which innumerable infectious foci resemble small “millet seeds” that are typically 1-3 mm in diameter (red arrows).

Incorrect Answers:
Answer 1: Intravenous amphotericin B is a potent antifungal medication that is reserved for severe fungal infections due to its toxicities, particularly nephrotoxicity. While this patient’s constellation of signs and symptoms could resemble severe pulmonary coccidioidomycosis, empiric therapy with amphotericin B would not be performed without further workup in this patient, and would not precede respiratory isolation precautions.

Answer 2: Oral rifampin, isoniazid, pyrazinamide, and ethambutol are the mainstays of treatment for active TB. For patients with a strong likelihood of TB, particularly those with a significant illness presentation such as this patient, starting these medications empirically prior to diagnostic TB confirmation may be life-saving. However, initiation of these medications should not precede respiratory isolation precautions.

Answer 3: Rapid sequence intubation involves rapid administration of a sedative (e.g., ketamine) followed by a paralytic (e.g., rocuronium) and is a preferred method of intubation in the emergency department as it lowers the risk of aspiration for patients who have not fasted. While this patient is tachypneic with accessory respiratory muscle use, he is still saturating above 90% on room air. Prior to resorting to intubation, less invasive measures such as supplemental high flow nasal cannula or continuous positive airway pressure should be attempted.

Answer 5: Sputum sample acquisition is the next diagnostic step to confirm TB via an acid-fast bacilli (AFB) smear, mycobacterial culture (often takes weeks), and nucleic acid amplification test (NAAT). Typically, 3 sputum samples are collected or induced 8 hours apart in a 24 hour period. However, for the safety of hospital staff, patients must be under respiratory isolation precautions while undergoing this workup.

Bullet Summary:
Patients who are at high risk for tuberculosis (e.g., prisoners) who present with a suspicious history for active disease (e.g., cough, fever, night sweats) must be put on airborne respiratory isolation precautions early on in their workup.