title: Epidemiology of extra-pulmonary tuberculosis in the United States: high rates persist in the post-HIV era.
abstract: BACKGROUND
  The incidence of tuberculosis (TB) in the United States has declined following a logarithmic pattern, with few exceptions. One exception was during the acquired immunodeficiency syndrome (AIDS) epidemic, which was thought to have caused the deviation. However, since then, alternative explanations have been proposed, including the increased burden of chronic diseases, immigration, and the increase in the use of immune suppressant medications.
  
  
  METHODS
  Epidemiological data of the Center for Disease Control and Prevention (CDC) and the Bureau of the Census were analyzed regarding TB incidence, human immunodeficiency virus (HIV) infection, immigration status, and age for the period 1953-2011.
  
  
  RESULTS
  Data analysis identified a deviation from the logarithmic decline in TB cases that started in the mid-2000s. This divergence did not appear to be related to HIV status. The overall decline in TB cases since 1953 has been almost exclusively due to a reduction in pulmonary TB (PTB) and not to extra-pulmonary TB (EPTB).
  
  
  CONCLUSIONS
  The HIV/AIDS epidemic likely played a significant role in the 1979-1985 deviation, but not subsequently. Furthermore, EPTB as a proportion of total TB cases has remained high. Further studies to delineate the etiologies of these findings are needed.
authors.affiliation: Department of Pulmonary and Critical Care Medicine, College of Public Health, East Tennessee State University, Johnson City, Tennessee, USA.
authors.forename: H
authors.initials: H
authors.lastname: Adada
authors.affiliation: Department Biostatistics and Epidemiology, College of Public Health, East Tennessee State University, Johnson City, Tennessee, USA.
authors.forename: M A
authors.initials: MA
authors.lastname: Valley
authors.affiliation: Department of Pulmonary and Critical Care Medicine, College of Public Health, East Tennessee State University, Johnson City, Tennessee, USA.
authors.forename: S A
authors.initials: SA
authors.lastname: Nour
authors.affiliation: Department of Pulmonary and Critical Care Medicine, College of Public Health, East Tennessee State University, Johnson City, Tennessee, USA.
authors.forename: J
authors.initials: J
authors.lastname: Mehta
authors.affiliation: Department of Pulmonary and Critical Care Medicine, College of Public Health, East Tennessee State University, Johnson City, Tennessee, USA.
authors.forename: R P
authors.initials: RP
authors.lastname: Byrd
authors.affiliation: Department Biostatistics and Epidemiology, College of Public Health, East Tennessee State University, Johnson City, Tennessee, USA.
authors.forename: J L
authors.initials: JL
authors.lastname: Anderson
authors.affiliation: Department of Pulmonary and Critical Care Medicine, College of Public Health, East Tennessee State University, Johnson City, Tennessee, USA.
authors.forename: T
authors.initials: T
authors.lastname: Roy
mesh_terms: D017677:Age Distribution; D000367:Age Factors; D019352:Censuses; D002487:Centers for Disease Control and Prevention, U.S.; D016009:Chi-Square Distribution; D060085:Coinfection; D054242:Emigrants and Immigrants; D058872:Epidemics; D015658:HIV Infections / Q000175:diagnosis / Q000453:epidemiology* / Q000276:immunology; D006801:Humans; D016867:Immunocompromised Host; D007166:Immunosuppressive Agents / Q000009:adverse effects; D015994:Incidence; D016014:Linear Models; D012307:Risk Factors; D013997:Time Factors; D014376:Tuberculosis / Q000175:diagnosis / Q000453:epidemiology* / Q000276:immunology; D014481:United States / Q000453:epidemiology
chemical_list: D007166:Immunosuppressive Agents