In chemotherapy treatments it is very important to control the level of white blood cells of patients. Knowing in real time if this side effect of the treatment is occurring can reduce the more than 250,000 infections detected annually in Europe. A team of researchers from the Polytechnic University of Madrid (UPM) and the Massachusetts Institute of Technology (MIT) developed a portable device that detects patients’ white blood cell levels. A blood sample is not necessary and can be used at home.
The microscopy device allows looking through the skin of the finger, using blue light that penetrates between 50 and 150 microns under the skin, and makes a video of the blood cells that flow through the capillaries of the surface of the skin. Specifically, the device is used in “the nail bed, an area where the capillaries are so narrow that white blood cells must pass one by one, making them easier to see,” says researcher Carlos Castro-González.
In the capillaries small particles can be observed moving in the blood flow and the researchers have developed an algorithm that identifies and counts these particles to obtain an estimate of the number of white blood cells. If the levels are below the threshold that doctors consider dangerous, they can immediately treat the patient.
The technology does not provide an accurate white blood cell count, but reveals whether patients are above or below the minimum: about 500 neutrophils (the most common type of white blood cells) per microliter of blood.
Oncologists will have a greater guarantee of the patient’s condition. “Normally, doctors want chemotherapy to be as intense as possible, but without people being immunosuppressed. The current 21-day cycles are based on statistics of what most patients can tolerate; but if you are ready before, then you may be given your next dose in advance, and that translates into better survival,” says the Dr. Álvaro-Sánchez Ferro.
The device prototype, which has been tested in 45 chemotherapy patients from the Massachusetts General Hospital and the La Paz Hospital in Madrid, has demonstrated 95% accuracy in the identification of patients with low white blood cell levels. “Knowing if this side effect is occurring could reduce complications in more than half of the cases,” says Castro-González.
Researchers are building a new practical prototype. “Automating the measurement process is essential to making a device for domestic use viable,” says Ian Butterworth, a researcher at MIT who has participated in the development of the prototype. “The images should be collected in the right place of the patient’s finger, and the operation of the device should be as simple as possible,” adds Butterworth.
“The next step is to adapt the technology so that more accurate white blood cell counts can be generated; very useful for controlling patients undergoing bone marrow transplants or people with certain infectious diseases,” concludes the researcher Castro-González.
Source: Agencia ID