Evidence that Theranos may have returned potentially faulty results to patients have been documented in a government investigation, the Wall Street Journal reports.
Citing people familiar with the documents, The Journal’s John Carreyou and Christopher Weaver report that the blood-testing company gave results even though they were aware of quality-control issues.
The documents came from a report from the Centres for Medicare and Medicaid Services, the federal agency responsible for regulating laboratory test. The documents are not yet publicly available.
CMS, which also issued a warning letter to Theranos in January, cited laboratory personnel problems, issues with analytics systems and hematology concerns for the blood-testing company’s Newark, California lab. Theranos has since submitted a plan of correction to CMS.
In the hematology category, the letter read “it was determined that the deficient practices of the laboratory pose immediate jeopardy to patient health and safety.”
The Journal reports that between April and September 2015, Theranos sent blood-test results back to 81 people on blood thinners. Having accurate results for the amounts of blood thinners in the body is crucial, because too much can cause fatal bleeding while too little could cause clots to form that could lead to stroke or other complications.
Blood thinners are particularly tricky to test for, so most laboratories use a deviation rule that helps make sure the test is within certain parameters that would make it accurate. The investigation found that the results fell outside that deviation rule, The Journal says.
Theranos has since notified any patients who could have been affected, a spokeswoman told The Journal.
The issues with the results are not due to the company’s proprietary finger-prick technology, but rather from traditional blood samples run on standard blood-testing devices.
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