Compact microscope for early sepsis diagnosis

Researchers from The Institute of Photonic Sciences (ICFO) in Barcelona have developed a portable microscope that could dramatically reduce the time for identifying sepsis.

Commonly referred to as ‘blood poisoning’, sepsis kills over 20,000 people per day worldwide, making it more deadly than prostate cancer, breast cancer and HIV/AIDS combined. Current techniques to test for the disease can take up to a day. However, using a combination of photonics technology, microfluidics and molecular biology, the new method can produce a result in just 30 minutes, with the test costing as little as €50 per patient.

The microscope sends polarised beams of light through birefringent crystals, a cartridge containing a blood drop, and an array of receptors. The device is able to detect the interaction of light with the bacteria or proteins captured by the receptors. Physicians can assess the type and quantity of biomarkers present based on the intensity of the transmission image. According to the researchers, the system produces sample-to-result processing up to 50 times quicker than current methods.

“Doctors need a quick, reliable way of detecting sepsis and what stage it has reached,” said Dr Josselin Pello, senior researcher on the project.

“Current methods exist, but they are too slow: they can only look at a couple of parameters at a time and they will not tell the physician what type of bacteria is present that is causing sepsis. A doctor may not therefore prescribe the correct treatment in time.”

Known as RAIS (Scalable point-of-care and label free microarray platform for rapid detection of sepsis), the microscope system can detect many biomarkers, including micro-ribonucleic acids and interleukins. This means it can also be used to detect a multitude of bacterial infections alongside sepsis, such as E. coli, staphylococcus, and meningitis.

The portable, point-of-care device comes with integrated software, and the ICFO team says it is simple to operate and could be used in remote areas by junior physicians. Further down the line, the system may even be developed so that self-diagnosis could be possible.

“Although we are a long way off this, a self-diagnosis kit would certainly help with conditions like meningitis where an early diagnosis could be the difference between life and death,” said Pello.