The symptoms of TB are often non-specific: persistent cough, fever, night sweats, and/or weight loss. Thus, one must have a high index of suspicion for TB (i.e. THINK TB) in order to prevent delayed diagnoses and possible exposure to others. Among patients with active TB, those with an active cough, cavitary lesions on chest x-ray, a smear positive for AFB, or actively draining lesions of the oral cavity or respiratory tract are most infectious. Therefore, the diagnosis of pulmonary TB must be considered in any of the following clinical situations:

	A patient with a positive sputum smear for AFB (acid fast bacilli).
	A patient whose chest x-ray has upper lobe infiltrate(s) or cavitary lesions in any lobe.
	A patient with an undiagnosed pulmonary process with cough in whom an alternative diagnosis is not strongly suspected nor supported by laboratory testing AND one of the following risk factors:

a)	known recent exposure to TB
b)	known history of TB or +PPD
c)	known or suspected immunosuppressive state (e.g. HIV infection, immunosuppressive therapy)
d)	alcohol abuse or injection drug use
e)	past or current homelessness or incarceration
f)	born or emigrated from a high prevalence area of the world for TB (i.e. Asia-Pacific Islands, Africa, South or Central America, or Eastern Europe)
g)	history of fever AND weight loss AND night sweats

Medically undeserved or high-risk racial/minority groups such as Native Americans, Native Alaskans, etc.