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On The Killer’s Trail
With the aid of blood tests
sepsis is detectable; © SXC
„To diagnose sepsis is much more difficult than to diagnose an acute heart attack”, explains Frank Martin Brunkhorst who is executive director of the German Sepsis Society in Jena. Symptoms like high fever, shivering and a low blood pressure are not only specific for blood poisoning but also for a lot of other diseases, like influenza. That is why sepsis is often detected too late.
Most people do not know that sepsis is the third most common death cause in Germany with about 60,000 deads every year. To reduce this high number, researchers are working on tests allowing faster and more precise diagnoses. Also intensive care specialist Brunkhorst supports the improvement of diagnostics and treatment.
Procalcitonin – A Solid Sepsis Biomarker
In the past, it took two to three days to obtain positive results from blood cultures but now the biomarker procalcitonin (PCT) - a thyroid hormone - allows speeding up the detection of sepsis. High concentrated PCT is a solid and early indication of a developing serious sepsis. “PCT tests provide results in only two hours”, Brunkhorst says. Promptness of detection is especially important as mortality rises by seven percent per hour.
Sometimes a inflamed toe or bronchitis are enough to threaten the body. If the immune system cannot defeat the bacteria - in rare cases also viruses or fungi - on the spot, these will spread via the bloodstream and the organs will get infected one after another.
The result is an overreaction of the immune system that makes every possible effort to battle the bacteria. White blood cells’ antibodies do not only attack the hostile germs, but also the own body. The result is a circulatory collapse and organ failure.
Only around 60 percent of all patients suffering from a serious sepsis survive. The disease should be better under control by now, but the fight against it is difficult. Brunkhorst explains: “The PCT test does not show the reason for the infection”, which is the ultimate requirement for an effective and specific antibiotic therapy.
PCR: Promising Method
Therefore, having a look at the genetic material suggested itself. With the aid of PCR (polymerase chain reaction) tests the DNA of the bacterium can be visualised and identified within a few hours. Another advantage of these tests: in contrast to conventional blood cultures, they also detect antibioticly pre-treated bacteria.
Researchers from Jena have developed a new PCR test. “Our test VYOO detects 99 percent of all sepsis causing agents within only eight hours”, says head developer Marc Lehmann of Sirs Lab.
Another important advantage: „VYOO is not only able to decipher the agent DNA, but also detects bacterial antibiotic resistances”, Lehmann proudly explains. Yet, the detection can only succeed in five of forty possible sepsis germs.
That is why the search for efficient tests is being continued. Also the development of new drugs has to be intensified as “the antibiotic resistances are rising”, warns Brunkhorst. In case of antibiotic resistance the only way to fight the disease is by giving out-dated drugs. However, those drugs have not been applied for twenty years or longer since they are highly toxic and cause serious adverse affects.