The Washington Manual of Medical Therapeutics helps you diagnose and treat hundreds of medical conditions. Consult clinical recommendations from a resource that has been trusted on the wards for 50+ years. Explore these free sample topics:
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- Approximately 1.7 billion people are infected with tuberculosis; although less <15% progress to active disease, tuberculosis remains the leading infectious disease cause of death worldwide.1 In the United States, there were 3.1 cases per 100,000 in 2017. Most US cases occur in foreign-born individuals and result from reactivation of prior infection.
- Multidrug-resistant tuberculosis (resistance to both rifampin and isoniazid) has increased among immigrants from Southeast Asia, sub-Saharan Africa, the Indian subcontinent, and Eastern Europe. Extensively drug-resistant tuberculosis (MDR-TB plus resistance to fluoroquinolones and at least one of three injectable second-line drugs) is becoming increasingly prevalent in sub-Saharan Africa.
- High risk of tuberculosis exposure occurs among household contacts, prisoners, the homeless, IV drug abusers, and immigrants from high-prevalence countries. Persons at highest risk for progression include those with impaired immunity, such as HIV infection, silicosis, diabetes mellitus, chronic renal insufficiency, malignancy, malnutrition, and immunosuppressive medications, including therapy with tumor necrosis factor (TNF) antagonists.
- Latent tuberculosis infection (LTBI) is a misnomer referring to someone who has infection, but not disease (clinical and radiological evidence of active disease). The lifetime risk of progression to active disease is 10% (5% within 2 years of infection and an additional 5% thereafter). In poorly controlled HIV and other immunosuppressed patients, the annual progression rate from latent to active tuberculosis is 10%. Adequate treatment of LTBI can reduce the risk of disease up to 90%.2