Faster diagnosis of sepsis pathogens

Microbial pathogens can be diagnosed unambiguously and within just 24 hours by means of high-throughput sequencing of their genetic makeup and special bioinformatics evaluation algorithms. Fraunhofer researchers have validated this in a clinical study with sepsis patients. 

It is estimated that in Germany alone around 150,000 people fall ill with sepsis every year; despite medical advances, between 30 and 50 percent of the patients still die of the consequences.

One of the reasons for the high mortality rate: the diagnosis often comes too late for the lifesaving therapy with antibiotics that only combat the specific causative pathogen. In general the sepsis pathogens are detected by means of so-called blood cultures in which the pathogenic organism from blood samples of the patients are cultivated in the laboratory. Here, two to five days pass before the pathogens have multiplied and a result is available.

Due to rapid progress in nucleic acid analysis, the currently available high-throughput technologies (NGS, Next-Generation Sequencing) make it possible to sequence the complete genome of organisms within just a few hours and to check them against known gene sequences.

On the basis of these technologies researchers at the Fraunhofer Institute for Interfacial Engineering and Biotechnology IGB have developed an alternative diagnostic platform for sepsis. This enables them to identify bacteria, fungi or viruses directly by means of a sequence analysis of their DNA – without having to cultivate the pathogens beforehand in the laboratory. In a clinical study that the researchers carried out in cooperation with Heidelberg University Hospital, they have now validated their diagnostic method with blood samples from sepsis patients. Here, they identified the infectious microorganisms by means of the high-throughput sequencing of DNA circulating freely in the blood.