FDA Warns Inaccurate Lab Tests Harming Patients

November 23, 2015 — The FDA has concluded that unreliable laboratory tests are harming patients and the agency has asked Congress for increased oversight, according to the New York Times.

The FDA reviews tests used in multiple hospitals, labs, or doctor’s offices, but not so-called “laboratory developed tests” (LDTs), which are diagnostic tests performed in a single laboratory.

In the past, LDTs were simple tests for rare diseases. In recent years, they have become increasingly complex and higher-risk, now used to diagnose common and serious medical conditions like cancer and heart disease.

On November 16, the FDA issued a report (PDF) on adverse events involving 20 LDTs where patients were harmed:

“Due to false-positive tests, patients were told they have conditions they do not really have, causing unnecessary distress and resulting in unneeded treatment. In other cases, the LDTs were prone to false-negative results, in which patients’ life-threatening disease went undetected.”

For example, one LDT used to detect the HER2 gene mutation linked to breast cancer failed to detect it 20% of the time. As a result, patients did not receive HER2-targeting drugs or the best treatment.

Another example is inaccurate prenatal tests to detect generic abnormalities. False-positives may result in a woman aborting a normal pregnancy, while women with false-negatives deliver a child with an unanticipated genetic syndrome.