A JAMA THEME ISSUE
Edited by Catherine D. DeAngelis, MD, MPH, and Annette Flanagin, RN, MA
Grant and colleagues investigated the effect of isoniazid therapy on
new and recurrent cases of TB in a cohort of South African miners infected
with HIV but without evidence of active TB. Although TB incidence remained
high compared with rates before the intervention, over a median 22.1 months
of follow-up, TB incidence declined 38% in the entire cohort and 46% among
men with no prior history of TB.
Multidrug-resistant TB (MDR-TB) has declined in the United States, but
it continues to be a problem worldwide and is the subject of 2 articles in
this issue. First, Drobniewski and colleaguesArticle report
results of a population-based molecular epidemiological study to determine
the prevalence of the Beijing-family strain of MDR-TB in civilian and incarcerated
populations in the Samara region, Russia. They found Beijing-family strains
in 66.6% of cases, with an even higher prevalence in individuals with a history
of incarceration. In a second study, Granich and colleaguesArticle reviewed
California data on MDR-TB from 1994-2003 and found that the proportion of
MDR-TB cases remained stable at 1% to 2% over the study period, with 83% of
cases among California residents who were born outside the United States.
In a commentary, NettlemanArticle discusses factors
associated with MDR-TB and its containment.
Traditionally, primary and reactivation TB have been thought to have
distinctive radiographic features. In a study using DNA fingerprinting to
distinguish recent from distant acquisition, Geng and colleagues examined
radiographic features from 456 TB cases and found little correlation between
radiographic appearance and time of TB acquisition. Patients with TB and HIV
infection commonly had atypical radiographs.
Two articles in this issue compare results from 2 generations of a whole-blood
interferon γ (IFN-γ) assay with tuberculin skin testing (TST)
to identify persons with latent TB infection. Pai and colleaguesArticle examined
health care workers in rural India and found similar prevalence estimates
(approximately 40%) using either test and high (81%) agreement between the
TST and IFN-γ methods. In the second article, Kang and colleaguesArticle report TST and IFN-γ assay results from Korean
individuals who had received bacille Calmette-Guérin vaccination and
were estimated to have a minimal to high risk of infection. They found that
the IFN-γ assay provided a better indication of TB risk than TST. In
a commentary, WhalenArticle discusses screening for
latent TB infection.
Dye and colleagues analyzed World Health
Organization data on TB prevalence, treatment outcomes, and death and analyzed
national prevalence surveys of infection and disease to evaluate the prospects
for reducing global TB incidence, prevalence, and death rates to levels consistent
with internationally recognized goals by 2015. They estimate the goals could
be reached in many regions of the world, with Africa and Eastern Europe posing
the greatest challenges.
Efforts are under way to design a better vaccine to prevent tuberculosis
and to develop novel drugs to treat the disease.
In the United States, patients with TB who are homeless are more likely
to have a history of substance use or incarceration and less likely to be
born outside the United States or have multidrug-resistant TB compared with
those who are not homeless.
Recommendations for the treatment of active and latent TB infection.
Without access to appropriate and effective health care, everyone is
vulnerable to TB.
For your patients: Information about tuberculosis.
This Week in JAMA . JAMA. 2005;293(22):2693. doi:10.1001/jama.293.22.2693