"Early diagnosis is the key to improving treatment of these diseases," said Ellen Beaulieu, who reported on the test. "Diagnosis with conventional tests is difficult in developing countries where these diseases occur. We hope that our low-cost, simple test will play a role in helping poorer parts of the world combat these diseases and the poverty they engender."
One existing test for diagnosing the three diseases involves taking a blood sample from a patient and examining it under a microscope for the parasites that cause the diseases. But the process is complex, requiring medical laboratory equipment and specially trained health care workers. Current blood tests are also time-consuming. In some cases, it can take up to 90 days to confirm results. Other tests detect the parasites using antibodies. But they require expensive electronic equipment that may not be available in remote areas of the developing world.
The new test exploits the common heritage of the parasites that cause Chagas, leishmaniasis, and African sleeping sickness. All three are closely related members of what scientists know as the trypanosomatidae family. The researchers developed special dyes that, according to them, allow detection of an early disease stage, does not require the use of sophisticated lab equipment, and can produce results in as little as one hour.
Initial tests under laboratory conditions show that the dyes reveal the presence of the parasite marker and glow in ultraviolet light from a simple, handheld lamp. The researchers report they are making progress toward improving the sensitivity of the dyes.
The goal is to develop a "dipstick" version of the test that allows detection of the parasite metabolite using a simple paper strip like those used in urine tests for diabetes. Such a test could allow health workers in remote areas to diagnose the diseases by dipping the strip in a drop of blood and exposing it to ultraviolet light. .
MEDICA.de; Source: American Chemical Society