Less Common Respiratory Conditions: Pulmonary Tuberculosis

Tuberculosis (TB) is the leading cause of infectious disease-related mortality worldwide, affecting 1.7 billion individuals with 9,000 new cases annually in the United States. Disease burden in the United States is greatest among immigrants from areas with high TB rates (eg, India, China, Philippines, Vietnam). Active TB infection can be recently acquired or latent TB infection (LTBI) that becomes active long after initial infection. LTBI testing is recommended for health care workers at hire, immigrants from high-burden areas, and those in high-risk environments (eg, homeless shelters, correctional facilities, long-term care). Health care workers can be tested with interferon gamma release assays (IGRA) or tuberculin skin tests (TSTs). For others older than 5 years, IGRA is recommended. For children younger than 5 years, TSTs are recommended. If test results are positive, several new therapeutic regimens have replaced the previously standard 9-month isoniazid regimen. For patients suspected of having active TB, testing involves chest x-ray, sputum for microscopy, cultures, and nucleic acid amplification tests. Active TB is managed with 2-months of intensive 4-drug therapy, followed by a 4-month continuation phase with isoniazid and rifampin. If multidrug-resistant TB is diagnosed, consultation with infectious disease subspecialists and the health department is recommended.