3. TB Perspectives… a few introductory slides
Eric Brenner, MD
Bureau of Disease Control
SC DHEC
Dept of Epidemiology and Biostatistcs
USC School of Public Health

4. 43 y.o. man with extensive TB in the left lung
His 18 month-old son with a strongly positive Mantoux and CXR showing collapse of the RML due to “primary TB” (RML infiltrate + R hilar adenopathy)

6. Goal of TB Control Programs
Interrupting the chain of transmission…!!!
Why do we treat patients with pulmonary TB?
Personal health goal => cure the ill patient
Public health goal => interrupt the chain of transmission

7. Mycobacteriology Laboratory - III AFB Smears
Detects presence of mycobacteria (and occasionally other uncommon pathogens as well - e.g. Nocardia)
Cannot distinguish M. TB from NTM.
Clue to possible diagnosis AND to potential infectiousness of patient.
Always interpret in context of all other findings.

8. Mycobacteriology Laboratory - IV More Positive AFB Smears (*)
(*) Again with traditional Ziehl-Neelsen staining which most hospitals can do

9. M. Tuberculosis colonies growing on agar in the laboratory

10. Reported TB Cases* United States, 1982–2008
No. of Cases
Year
*Updated as of May 20, 2009.

11. Number of TB Cases in U. S. -born vs
Number of TB Cases in U.S.-born vs. Foreign-born Persons United States, 1993–2008*
No. of Cases
*Updated as of May 20, 2009.

12. WHO Global TB Report 2007

13. WHO Global TB Report 2007

14. Geneva, Switzerland

15. The “Pont du Mont Blanc” where the Lake of Geneva empties into the Rhone River

16. The old “League of Nations” Building (now part of UN)

17. HQ of the World Health Organization

18. Schema of the Pathogenesis of Tuberculosis
Dissemination via circulation to distant sites including (i) apex of lungs; (ii) kidneys, (iii) bone, (iv) brain, (v) multiple other sites. Potential for disease to occur in 5-10% of infected persons; months, years, decades later.
Lymphatics => systemic circulation via the thoracic duct
Typical apical cavitary disease seen in many patients who have TB from late reactivation of Latent TB Infection (LTBI)
Site of initial infection often peripheral (sub-pleural)
Spread via pulmonary lymphatics
Hilar lymph nodes (hilar adenopathy)

19. Natural History of Tuberculosis (Schema)
No disease, but LTBI
Still no disease, but possible lifelong LTBI
Disease “anytime later in life” [reactivation of LTBI)
95%
90%
Not Infected
Infected +
100%
Disease “soon” [within 1-2 yrs] 5% 5%
Caution !! Co-infection with HIV totally upsets this schema! Instead of having a 10% lifetime risk of developing TB disease persons co-infected with HIV may have a risk as high as 10% per year!!!!