RT Book, Section A1 Erdman, Sharon M. A2 Attridge, Rebecca L. A2 Miller, Monica L. A2 Moote, Rebecca A2 Ryan, Laurajo SR Print(0) ID 57292636 T1 Chapter 34. Tuberculosis T2 Internal Medicine: A Guide to Clinical Therapeutics YR 2013 FD 2013 PB The McGraw-Hill Companies PP New York, NY SN 978-0-07-174580-2 LK accesspharmacy.mhmedical.com/content.aspx?aid=57292636 RD 2024/03/29 AB Most cases of human tuberculosis (TB) caused by Mycobacterium tuberculosis (MTB); Mycobacterium spp. are thin, rod-shaped bacteria with hydrophobic cells walls → resistant to decolorization during Gram staining (acid-fast bacilli [AFB])Risks for developing TB infection after exposure include proximity to & infectiousness of TB patient, duration of exposure, immunocompetence of exposed individual; risk of developing active TB infection highest w/in 2y of exposure; 10% of patients who acquire TB develop active infection without chemoprophylaxisCutaneous TB occurs via direct inoculation through skinTB exists as rapidly growing extracellular organisms (in cavities, where resistance may exist), slow-growing organisms (in acidic/necrotic tissue, often cause for treatment failure/relapse), or dormant organisms (alternating periods of dormancy & growth → treatment failure/relapse with inadequate therapy)