DETROIT -- Men and women with the human immunodeficiency virus (HIV) have a higher incidence of tuberculosis if they live in the eastern United States or test positive for mumps, say researchers at Henry Ford Hospital.
The scientists report in the Jan. 15 issue of the Annals of Internal Medicine that patients in the eastern United States were at increased risk for tuberculosis (TB) especially if they had low levels of CD4 cells, which indicate the general health of an individual's immune system.
"This study gives us some key indicators that could help physicians develop strategies to prevent tuberculosis infection or halt disease outbreak once infection has occurred," says one of the study's principal investigators Paul Kvale, M.D., a senior staff physician in pulmonary and critical care medicine at Henry Ford Hospital.
"Since HIV-infected patients are at a 50-to-200 times greater risk of contracting tuberculosis, the findings can help attack a very real threat in the fight against AIDS," Dr. Kvale adds.
Researchers in the multi-center study examined 1,130 HIV-positive patients in Detroit, New York, Newark, Chicago, San Francisco and Los Angeles from 1988-94. Of the 31 study participants diagnosed with TB, nearly 25 percent of died from the disease.
Scientists tested patients using the purified protein derivative (PPD) skin test, the standard method to detect TB. But in some instances, PPD tests fail to show exposure to TB, especially in patients with suppressed immune system like those with HIV. The disease, therefore, can advance undetected.
"Because TB is an infectious disease that can rapidly progress and lead to death, any finding regarding risk or prevention is significant," Dr. Kvale says.
TB is an opportunistic, air-borne disease that is highly contagious. Its symptoms usually include fever, night sweats, difficulty in breathing and a deep, hacking cough. It also can originate in organs other than the lungs.
Researchers say further studies are needed to look for ways to prevent the spread of TB within high risk populations.