SPIT'S NEW IMAGE: A TOOL FOR DIAGNOSING DISEASE

Among ancient peoples, it is said, this precious bodily fluid was used as
the basis of a primitive lie detector test. The accused would be given a
handful of rice and told to swallow it; if he couldn't, it meant he was
nervous - and guilty.

This slippery stuff also helps moisten and digest food, and has healing
powers as well - proteins that fight bacteria, fungi and viruses and others
that speed tissue healing, says Dr. Irwin Mandel, professor emeritus at
Columbia University. In fact, animals that lick their wounds heal faster
than those who don't.

The fluid in question, of course, is saliva, or actually, spit - a
combination of the saliva pumped out by salivary glands and all the other
effluvia floating around in our drool: drugs (licit and otherwise), bugs
(viruses, fungi, bacteria), hormones, antibodies and anything else small
enough to seep out through tiny blood vessels into the mouth.

As unpleasant as it all sounds, spit is in. In fact, it could be the
diagnostic fluid of the future, according to scientists who plan to gather
next week at the National Institute of Dental and Craniofacial Research to
explore spit's many wonders - and economic potential.

Already, a number of companies are using the Internet to tout spit test
kits, some of which have not been approved by the US Food and Drug
Administration, which acknowledged last week it's scrambling to keep up.
With the kits, consumers muster a little spittle, fork over $60 or so and
send the sample to a lab to find out whether, say, their testosterone is
tanking, their estrogen slipping, or their stress hormones soaring.

Spit, or more elegantly, oral fluid, is almost identical to the clear part
of blood, but with everything - including infectious organisms - present in
weaker concentrations. In the past, diagnostic tests were not sensitive
enough to detect these low concentrations, but now they are. That means
that almost anything that can be detected in blood can theoretically be
found in spit, too - with less pain, risk of infection and expense.

Spit testing is cheap because it's so safe - neither patient nor health
care worker can get stuck with a needle. ''You don't need a technician to
get the sample,'' says Dr. Stephen Sonis, chief of oral medicine at
Boston's Brigham and Women's Hospital.

So far, spit tests have only been FDA-approved for a few limited uses - to
detect the AIDS virus, illegal drugs, alcohol, a hormone that signals
premature labor, and periodontal disease. There are no tests that allow a
person to both collect and analyze spit at home - yet. With the OraSure kit
made by the Epitope Corporation of Beaverton, Ore., for instance, you have
to go to a health care professional, who puts a toothbrush-like swab
between your cheek and gums for a few minutes, then sends the sample to a
lab to be tested for HIV. Insurers also use the OraSure kit to test for
marijuana, cocaine, opiates or methamphetamines. In other countries, the
kit is used to collect spit for testing for hepatitis B and other diseases.
And soon, this kit and others like it could be used to get DNA for testing
from prisoners on parole or people at risk for genetic diseases. (It's
unlikely, by the way, that spit samples could be collected surreptitiously
from, say, a coffee cup or eating utensil, because the sample would be too
small and would degrade quickly without preservation.) But as spit
collecting and preservation techniques evolve, do-it-yourself spit tests
could be commonplace.

Already, doctors use spit tests to monitor hormonal changes in infertile
women, says Dr. Philip Fox, former clinical director at the National
Institute of Dental and Craniofacial Research at NIH and now research and
development director at Amarillo Biosciences Inc., in Amarillo, Tex.
Similarly, SalEst, made by Biex, Inc. in Dublin, Ca. allows women at risk
of premature labor to have their spit tested by a doctor for the hormone
estriol. If estriol rises before 36 weeks of pregnancy, it's a signal the
woman may go into labor prematurely.

But it is the gray area of spit testing through companies on the Web that
concerns the FDA, which worries about consumers putting their trust in
diagnostic tests that have not been approved.

The Great Smokies Diagnostic Laboratory in Ashville, N.C., for instance,
offers spit tests for a number of hormones through its website
(www.bodybalance.com). You pick the test - StressCheck, MaleCheck or
FemaleCheck - pay $60 and send in your sample to see if your hormones are
in the normal range. No doctors are involved.

The company claims the tests are ''screening'' tools, not true diagnostic
tests, and admits its tests are not approved by the FDA. After inquiries
from the Globe, the FDA said it is ''concerned about the Great Smokies
advertising and promotion as well as about other firms that advertise and
promote lab tests on the web.'' While it is not illegal for labs to set up
an in-house testing service and offer it through health care professionals,
it is illegal to offer this service directly to consumers, says Dr. Steven
Gutman, director of the FDA's division of clinical laboratory devices.

But ''the beauty of the test'' for consumers, argues Dr. Alison Levitt, a
physician at Great Smokies, is precisely that ''you don't need to go to the
doctor...People are interested in their hormone levels. People want
numbers.'' Aeron LifeCycles Clinical Laboratory in San Leandro, California
used to offer spit tests directly to consumers, too.

But last year, after federal and state regulators reviewed the lab's
practices, the company decided to put doctors in the loop, though you still
don't need to actually talk to a doctor to be tested, notes George Romero,
customer service manager.

You simply send in your spit and $44, pick a name off a company-supplied
list of doctors and that doctor signs the test order. For an additional
fee, that doctor will help interpret the results, which you also get sent
directly. But how useful is it to send off some spit and get a few numbers
that you try to interpret? Probably not very - in part because some hormone
levels fluctuate wildly.

To test for stress, for instance, the Great Smokies lab checks levels of
two hormones, DHEA (dehydroepiandrosterone) and cortisol. But cortisol
levels vary over a 24-hour cycle, so if you send in only two samples a day,
as the company website suggests, the potential for misinterpretation would
appear to be high. In the version of the stress test sold to doctors,
hormones are measured four times a day, says Great Smokies physician
Levitt. For researchers, however, it is precisely this variability in
hormone levels that makes spit-tests a gold mine because they can track
physiological changes almost in real time.

''When cortisol goes up in the blood, we find it in saliva within 20
minutes,'' says Douglas Granger, a Pennsylvania State University behavioral
endocrinologist. In studies of people before and after roller coaster
rides, cortisol in saliva shoots up within 15 minutes, then returns to
normal in an hour. In other work, Granger has found similar cortisol spikes
in kids experiencing family stress.

In one test, he asked mothers and kids to discuss a topic about which they
disagreed, then had the kids spit into little cups. The kids judged the
most anxious by other tests showed the highest rises in cortisol levels,
says Granger, who has formed a research company to study spit for a number
of hormones.. Ultimately, with more sophisticated spit kits, consumers
could test their oral fluids at home. What spit testing offers, says, Dr.
Irwin Mandel, affectionately known among researchers as ''the grandfather
of spit,'' is ''a lick and a promise'' - a simple, reliable way of
monitoring health.