Nanoparticle-Based Method Rapidly Detects Fungal Blood Infection

When Candida fungi get into a person’s bloodstream, typically during a hospital stay, the resulting infection, called candidemia, is deadly 40% of the time. Diagnosing the infection, which affects 1 out of 10,000 people in the U.S., can take up to five days, delaying treatment. A team of researchers has now developed a nanoparticle-based technique that detects Candida in blood samples in less than three hours (Sci. Transl. Med., DOI: 10.1126/scitranslmed.3005377). Key to the method’s success are magnetic iron oxide nanoparticles coated in Candida DNA fragments and a benchtop magnetic resonance detector, says team leader Thomas J. Lowery of T2 Biosystems, in Lexington, Mass. If fungi are present in a blood sample, their DNA will bind to the nanoparticles. The particles then cluster, which is noted by the magnetic resonance detector. With their protocol, the researchers can find as few as one Candida cell in a milliliter of sample. The scientists hope to conduct a clinical trial soon and have a test kit (shown) on the market next year.