CHECKUP\NEWS, TIPS & TRENDS\Saliva test speeds TB diagnosis.

A new saliva test for tuberculosis will give results in hours instead of days.

The test, approved by the U.S. Food and Drug Administration, is 95.5 percent accurate and gives results in four to five hours, says the manufacturer, Gen-Probe Inc. But because 5 percent of tests can be wrong, the FDA is requiring that all patients also receive standard TB tests, which can take up to five days for results.

Identifying TB quickly should help physicians and patients, because antibiotic treatment usually doesn't begin until test results are confirmed.

About 10 million Americans have been exposed to TB, and about 10 percent of those people will develop active cases that can spread the disease.

The test, called Mycobacterium Tuberculosis Direct Test, will cost laboratories between $20 and $30, but Gen-Probe could not say how much patients will pay.

No bone loss: Running doesn't promote bone and joint degeneration, a study conducted at Stanford Arthritis Center found. Researchers compared 28 longtime runners and 27 nonrunners older than 58 over a nine-year study. In fact, running seemed to be beneficial - the runners had more bone mass than the nonrunners. Runners averaged a total of two hours a week of exercise.

Aggravating asthma: A study backs up longtime advice to keep household dust and other allergens to a minimum when family members suffer allergies and asthma. The study, in the December issue of the American Journal of Respiratory and Critical Care Medicine, involved 120 adults and children with asthma who kept one-year journals in which they recorded their asthma symptoms. Researchers tested them for 13 common allergens, including dust mites and cat dander, and collected dust samples from their bedrooms and mattresses. In children allergic to dust mites, higher levels of dust mites in the home - particularly in the mattress - were linked to worse daily asthma symptoms and reduced lung capacity.

Treating infection may reduce premature births:A common bacterial infection in the vagina can trigger early labor, a new study confirms, and experts are calling for screening and treatment to reduce the number of premature births.

In a study of more than 10,000 pregnant women, those who had an infection known as bacterial vaginosis were 40 percent more likely to give birth to a premature, low-birth-weight baby than those who did not have the infection.

But treating the infected women with a combination of antibiotics may help offset the risk of early labor, according to another study in same journal.

Prevention of even a small proportion of preterm births could cut down on the number of deaths of babies who are too small to survive life outside of the womb, a research team headed by Sharon Hillier of the University of Washington in Seattle reported in the New England Journal of Medicine.

Preterm delivery occurs in about 10 percent of all pregnancies and is responsible for about 80 percent of deaths during or soon after birth, according to Dr. John Botti of the Hershey Medical Center in Hershey, Pa.

Approximately 12 percent to 22 percent of all pregnant women have bacterial vaginosis, according to the new study.