Snapshot A 21-year-old man presents to his primary care physician for a wellness visit. The patient currently has no acute complaints. He says that there are some medical forms he wants filled so he can start volunteering in the hospital. He denies any fevers, chills, night sweats, or unexpected weight loss. He recently returned from India for a medical mission. He immigrated from Mexico when he was young. He said that he cannot get the purified protein derivative skin test since he received the Calmette-Guerin vaccination when he was an infant. An interferon-gamma release assay returns positive. A chest radiograph is unremarkable. He is started on isoniazid and vitamin B6 for 9 months. (Latent tuberculosis) Introduction Mechanism of action login to view 3 more bullets Mechanism of resistance login to view 1 more bullet Clinical use login to view 3 more bullets Adverse effects login to view 8 more bullets