XML Feed for RxPG News   Add RxPG News Headlines to My Yahoo!   Javascript Syndication for RxPG News

Research Health World General
 
  Home
 
 Latest Research
 Cancer
 Psychiatry
 Genetics
 Surgery
 Aging
 Ophthalmology
 Gynaecology
 Neurosciences
 Pharmacology
 Cardiology
 Obstetrics
 Infectious Diseases
  AIDS
  Influenza
  MRSA
  Tuberculosis
  Shigella
  HCV
  SARS
  Ebola
  Dengue
  Malaria
  Pertussis
  Mumps
  Prion Diseases
  Small Pox
  Anthrax
  Leishmaniasis
 Respiratory Medicine
 Pathology
 Endocrinology
 Immunology
 Nephrology
 Gastroenterology
 Biotechnology
 Radiology
 Dermatology
 Microbiology
 Haematology
 Dental
 ENT
 Environment
 Embryology
 Orthopedics
 Metabolism
 Anaethesia
 Paediatrics
 Public Health
 Urology
 Musculoskeletal
 Clinical Trials
 Physiology
 Biochemistry
 Cytology
 Traumatology
 Rheumatology
 
 Medical News
 Health
 Opinion
 Healthcare
 Professionals
 Launch
 Awards & Prizes
 
 Careers
 Medical
 Nursing
 Dental
 
 Special Topics
 Euthanasia
 Ethics
 Evolution
 Odd Medical News
 Feature
 
 World News
 Tsunami
 Epidemics
 Climate
 Business
Search

Last Updated: Nov 17th, 2006 - 22:35:04

Tuberculosis Channel
subscribe to Tuberculosis newsletter

Latest Research : Infectious Diseases : Tuberculosis

   DISCUSS   |   EMAIL   |   PRINT
Blood-based TB test matches up to old skin test
Jun 8, 2005, 19:46, Reviewed by: Dr.

"Our study is the first time this blood test has been evaluated in India, where TB is highly endemic. It's also the largest study of its kind among health care workers, a group that is at high risk for occupational TB."

 
In a head-to-head matchup between a new blood-based tuberculosis (TB) test and the traditional tuberculin skin test, researchers from the University of California, Berkeley, and the Mahatma Gandhi Institute of Medical Sciences in India found that the two methods of detecting latent TB infection are equally good.

The results of the study, to be published in a special June 8 theme issue on tuberculosis in the Journal of the American Medical Association, mean that switching to the more expensive blood test may not be necessary for people in India.

"Our study is the first time this blood test has been evaluated in India, where TB is highly endemic," said Dr. Madhukar Pai, a post-doctoral fellow in epidemiology at UC Berkeley's School of Public Health and lead author of the paper. "It's also the largest study of its kind among health care workers, a group that is at high risk for occupational TB."

There are about 9 million new cases of TB each year, and a large proportion of the disease burden is in developing countries. Most people infected with TB contain the infection, and it remains latent. In some individuals, the infection progresses to active disease.

The tuberculin skin test, in which the skin is pricked with antigens from Mycobacterium tuberculosis, had stood alone for more than 100 years as the method for detecting latent TB infection.

However, many health professionals consider the skin test crude, said Pai, because it is unable to clearly distinguish between people who have received a vaccine against TB from those who have a true infection. Moreover, the skin test requires the patient to return three days after the skin prick so that a health worker can measure the resulting bump on the skin.

Having a test that allows health care officials to confirm a true TB infection is important because a positive test can lead to a six-month treatment of daily anti-TB drugs for the patient.

Pai said the development of a more advanced assay that uses specific TB antigens to detect levels of interferon-gamma, a protein released by the immune cells of people infected with tuberculosis, was greeted with a measure of excitement among health officials.

The test, called QuantiFERON-TB-Gold, has been approved by the U.S. Food and Drug Administration. Unlike the skin test, the interferon-gamma test requires only one visit by the patient, and its results do not rely upon the subjective interpretation of a health worker.

However, the new test requires special lab facilities, making it more expensive than the old skin test. The skin test, in turn, involves more personnel time because it requires health care workers to deal with a patient twice. "The new test may turn out to be more cost-effective in developed nations like the United States where labor costs are higher," said Pai.

For this study, researchers analyzed the results of 726 health care workers from the Mahatma Gandhi Institute, a rural hospital in Sevagram, India, that treats about 300 tuberculosis patients a year. The workers were tested with both the traditional TB skin test and the interferon-gamma assay.

About half of the workers tested positive for latent TB infection. The researchers found a high level of agreement - 81.4 percent - between the two tests. Surprisingly, previous TB vaccination had little impact on the results of either test.

Pai notes that other studies in North America and Europe have shown that the interferon-gamma test outperformed the skin test. "It's important to keep both tests on the menu so that health professionals can choose what's best for their target population," said Pai. "For high-burden, low-resource countries such as India, the skin test might still have value."
 

- June 8 theme issue on tuberculosis in the Journal of the American Medical Association
 

www.berkeley.edu

 
Subscribe to Tuberculosis Newsletter
E-mail Address:

 

Other UC Berkeley co-authors of the study include Dr. John Colford, Jr., associate professor of epidemiology, Dr. Lee Riley, professor of infectious diseases and Dr. Arthur Reingold, professor of epidemiology.

Related Tuberculosis News

Emergence of highly drug-resistant tuberculosis strains requires urgent action
Treating populations infected with HIV and latent TB could speed the emergence of drug-resistant TB
Solution to TB epidemic may lie in protective Heme oxygenase 1 protein
Explaining Why People of African Descent Are More Vulnerable to TB
Indian Scientists Identify Key Genes in Tuberculosis Infection
PA-824 holds promise for shortening the TB treatment regimen
DC-SIGN expressing alveolar macrophages are preferentially targeted by M. tuberculosis
Tuberculosis Still a Risk for Patients on Anti-retrovirals
Evolutionary history of tuberculosis is shaped by human migration patterns
TB vaccines will fail in developing countries


For any corrections of factual information, to contact the editors or to send any medical news or health news press releases, use feedback form

Top of Page

 

© Copyright 2004 onwards by RxPG Medical Solutions Private Limited
Contact Us