Procalcitonin Test Could Prevent Unnecessary Antibiotic Prescriptions

Every day, school is in session inside our bodies. And the students and teachers are one and the same: bacteria.

Bacteria are highly adaptive because they actually 'teach' one another to resist antibiotics. When one bacterium develops resistance to an antibiotic, it can share that resistance with similar and even unrelated strains. They do this by passing DNA-containing organisms called plasmids, from one to another. The result: Due to the excessive use of antibiotics, virtually all of the bacterial infections known to scientists are becoming resistant to even the most powerful antibiotics.

Fortunately, awareness of this overuse has led to a general rethinking about how best to utilise antibiotics. Now a new test has been developed that may provide doctors with the information they need to avoid prescribing antibiotics unnecessarily.

Sorting the Bs from the Vs

Antibiotics can only control bacteria - not viruses. But because many viral and bacterial infections have similar symptoms, doctors often prescribe antibiotics to treat viruses on the chance that they might be bacteria. So it's no mystery why many unneeded prescriptions are filled for respiratory infections and colds that are viral infections.

Currently there are tests that can determine the exact nature of an infection, but they tend to either take too long to show results or are too expensive to be practical. But a new test may change all that. This test quickly measures levels of procalcitonin, a blood protein that rises sharply in the presence of a bacterial infection. Procalcitonin levels rise only slightly in response to viral infections.

As reported in The Lancet medical journal last month, researchers at the University Hospital in Basel, Switzerland, devised a trial to examine the procalcitonin test. More than 240 subjects who were admitted to the hospital with lower respiratory tract infections were assigned either standard care, or care based on the results of a procalcitonin test.

In the procalcitonin group, 43 percent showed levels high enough to prescribe antibiotics. In the standard care group, patients were diagnosed using x-rays and other tests to determine infection type. In this group, 83 percent received antibiotics.

Favourable outcomes for patients in both groups were about equal, and none of the patients in the procalcitonin group experienced any adverse effects due to a lack of antibiotics. Follow-up tests to verify infection types confirmed that approximately 20 percent of the patients in both groups had bacterial infections.

One of the authors of the study observed that while antibiotics were over-prescribed in the procalcitonin group, 'The test halves antibiotic use, without altering the clinical outcome.'

No dipstick just yet

What the immediate future holds in store for the procalcitonin test remains to be seen. More research and development is required in order to transform it into what one antibiotic resistance expert calls a 'quick and easy dipstick test' that could reveal bacterial infection right away.

So it may be awhile yet before your doctor has a procalcitonin test ready to use in his surgery. In the meantime, doctors and patients alike need to be more careful about resorting to antibiotics to treat every sniffle, earache and cough. And the growing crisis of antibiotic resistance is only part of the reason to be wary.

Just last month, I told you about a large University of Washington study that revealed how excessive antibiotic use may be associated with an elevated risk of breast cancer. In that study, the women who had the highest rates of cumulative days of antibiotic use over 17 years had a sharply increased risk of death due to breast cancer.

And in another US study at The Henry Ford Hospital (Detroit), researchers followed 448 children from birth to seven years. Nearly half of the children received antibiotic treatments (mostly penicillin) within the first six months of life, and among these children the risk of developing asthma was two and a half times greater than the risk to children who received no antibiotics within the first six months. Risk of developing allergies was also significantly increased in the antibiotic group.

Good alternatives

Without question, antibiotics are important, life-saving tools. But the overuse of these drugs has to be curtailed or the antibiotic resistance crisis will turn into a disaster. So the next time your doctor suggests writing an antibiotic prescription, ask specific questions about why it's necessary and what other options might be workable.

For instance, in many cases a natural antibiotic could be just as effective as a pharmaceutical variety. In recently I reviewed four natural antibiotics recommended by US HSI Panellist Dr Allan Spreen: vitamin C, grapefruit seed extract, olive leaf extract and colloidal silver.

And I've made a special note to follow the progress of the procalcitonin test, which could emerge as the most important means of cutting back antibiotic use. As that develops I'll keep you posted.