Diagnostics for All (DFA), a nonprofit startup in Cambridge, MA, has designed a cheap, disposable blood test for liver damage. The device uses a stack of paper the size of a postage stamp for a test of toxicity for drugs to treat HIV and tuberculosis. This is a low cost, point-of-care diagnostic device for measuring liver function – critical for monitoring the adverse side effects of the powerful drugs used to treat HIV/AIDS and TB, and for managing the effects of viral hepatitis. It is currently impossible to economically monitor liver function outside hospital or laboratory settings; and this device will save hundreds of thousands of lives each year.

Disposable Blood Test for Liver DamageMany of the highly potent drugs used to treat HIV/AIDS and TB are toxic to the liver, deaths due to drug-induced liver failure are very rare in countries like the United States, where a patient’s liver function is monitored regularly. Yet this is not the case in resource-poor countries, where roughly 20% of TB patients and 25% of HIV/AIDS patients, lacking access to diagnostic tools, succumb to liver complications related to their treatment.

Designed specifically for use in the developing world, DFA’s device will enable semi-quantitative determination of two key liver enzymes, AST (aspartate transaminase) and ALT (alanine transaminase), which are routinely used to measure liver toxicity amongst patients receiving antiretroviral medications. As the liver becomes damaged by potent medications, these two enzymes, usually found in the liver, are released into the blood stream. From a single drop of whole blood, this test will determine whether blood levels of these two enzymes are baseline/normal, greater than two-times baseline/normal, or greater than five-times baseline/normal. The 2x and 5x thresholds, which indicate that treatments should be “monitored closely” or “altered immediately”, correspond to protocols established by the U.S. FDA to guide treatment during clinical trials.

The liver function test is targeted to cost $0.10 or less, will be about the size of a postage stamp, and will function without external power or equipment. The output will be a straightforward, semi-quantitative colorimetric indication of enzyme levels and will be easily integrated into telemedicine networks.

DFA plan to develop devices for broader assessments of patient health and for a range of important diseases such as TB, malaria, HIV/AIDS, and diabetes. For example, extending the functionality of the liver diagnostic device to detect kidney disease as well.