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I asked Theranos why my blood test results were wildly off from my ‘traditional’ labs, but no one ever replied

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A bloody revolution.
Published Last updated This article is more than 2 years old.

I first got interested in Theranos because the company’s founder, Elizabeth Holmes, promised to revolutionize (disrupt, if you insist) blood tests. With her Edison technology and hardware, you just walk into your neighborhood Walgreens, provide a few drops of blood from a finger, and for $5.35 you get a complete blood count. Easy and affordable.

I have a stake in this game. It seems a Hungarian forebearer of mine passed down an errant JAK2 gene that trips bone marrow into polycythemia vera (PCV), a fancy name for “too many blood cells”—and potential clots, especially as one’s vessels degrade with age. There’s no cure, yet, but with frequent attention the treatment is simple: Hydroxyurea, an inexpensive 19th century medicine—a urea derivative—which slows bone marrow output.

In homage to my ancestor, I perform a decade-old routine—a stroll to Stanford Hospital’s hematology lab to give blood samples that are tested for complete blood count (CBC) and metabolites. My numbers haven’t fluctuated much since my last visit, and the kind hematologist pronounces me “medically boring” (Pourvu que ça dure!). Good for me: If the hematocrit (HCT) number crosses the 45% threshold, I get to meet the vampire and “donate” 500 mL of blood. (After which this perfectly good pint of blood must be tossed. Regulations. Sigh…)

On my way back to my University Avenue office, a thought pops up: Why not try Theranos for comparison? I head back to my doctor’s office and get a test prescription from his obliging nurse. (In California, you still need a doctor’s prescription—not so in Arizona where Theranos successfully lobbied for prescription-free access to its tests.) A few minutes later, I’m in the small Theranos office inside the University Avenue Walgreens store. I give a few drops of blood and am told to create an on-line account and wait for the results.

After two failed attempts to establish a Theranos account, I gain access to my numbers:
— Platelets: 430. Given my condition, that’s high.
— Hematocrit: 44.1. A passing grade, but uncomfortably close to the 45% limit.

Stanford hematology disagrees:
— Platelets: 320. No concerns, come back in two or three months.
— Hematocrit: 41.1, ditto.

The differences are disquieting. Theranos’ numbers are an alarming 34% and 7% higher, respectively, than Stanford’s. Whom should I believe?

Curious and a bit troubled, I go for a Theranos retest a test a day later:
— Platelets: 375. A drop of 13% in 24 hours.
— Hematocrit: 40.6. -8.6%; now I’m well into the “safe zone.”

And then at Stanford, a day after that:

— Platelets: 297. A 7% drop.
— Hematocrit: 41.7. +1.5%; up a bit, but not alarming.

The Theranos numbers have two problems: They deviate significantly from the Stanford numbers and, more important, they deviate from themselves over a 24 hour period. Glucose concentration can vary hourly—but this is not true of platelets or hematocrit.

I write the CEO with facts and figures (and supporting documents), and request a response:

Dear Ms. Holmes,
A brief word of introduction:
I’m a 71 year old male, a customer of yours with a mild PCV condition treated by moderate doses of hydroxyurea (hydrea) and occasional 500 mL phlebotomies.
I’m also a techie and, among other things in 47 years in the tech industry, I once ran Apple’s Engineering in Cupertino. I’m compulsively curious, I like innovative technologies and was inevitably attracted to Theranos.
Now, the facts:
On June 29th I went to the Hematology lab at Stanford for routine CBC and Metabolites numbers.
As I walked back to Palo Alto, I stopped by my doctor’s office, got an order, went to the Theranos office at Walgreens on University Avenue in Palo Alto and got a CBC test.
Taken one hour apart, the Stanford and Theranos HCT numbers differ by about 7%: 44.1 Theranos vs. Stanford 41.1.
For platelets, the difference is even wider: Theranos 430 vs. Stanford 320.
Intrigued, I got a new order and went back to Theranos the following day, on June 30th. Theranos numbers were markedly different 24 hours later: HCT 40.6; PLT 375.
Just to make sure, I went back to Stanford for a second test today July 1st. Stanford HCT 41.7; PLT 297
I find the price and convenience of Theranos services attractive, but I worry about the reliability of the important HCT number.
What is the confidence interval in your measurement? + or – 1 point? + or – 5 points? I do get a phlebotomy at 45. How should I look at your June 29th 44.1 HCT number?
I’m curious to hear more about your methodology, standards and quality controls and would like to give you an opportunity to respond before I write a Monday Note on the broader topic of lab exams and other healthcare mysteries.
(Last but less important, setting up an account, getting the app to work was difficult, several system errors, unfriendly UI…)
Best regards,
—Jean-Louis Gassée

You can guess what happened: Nothing, no response. I shrugged it off and went on to other topics, but the question nagged at me. Theranos’ stated aim—inexpensive, painless blood tests—is admirable and, I hope, achievable. Consider my spouse’s recent blood test adventure…

Brigitte goes to a new doctor who starts with a CBC blood panel and directs her to the lab downstairs. The numbers come out well… but the out-of-pocket tab is five times the amount she used to pay at the local Quest Diagnostics lab. A successful lighting fixtures designer and builder of Palo Alto homes, my better half is a practiced fighter of suppliers and their creative invoices. She calls the lab: “How can you charge an inflated price tag for such a rote, totally automated test?” “Well, you see, we’re a teaching hospital… regulatory contortions let us charge much more than Quest. Our lab, our prices.”

Brigitte won’t be denied—trust me. The poor customer representative offers a payment plan. “No, that’s not the point. I can pay, but I won’t. Call me back when you’ve spoken with your supervisor!” A few days letter, a revised bill comes through the mail, accepting the insurer’s payment as full settlement.

We don’t all have Brigitte’s resolve. For the rest of us, the remedy is exactly what Theranos has promised: Commodification of reliable blood tests. But can Theranos deliver?

Last week, two Wall Street Journal stories (here and here) shed serious doubt on Theranos’ integrity. As the Journal reports, former employees have accused the company of various forms of misrepresentation and even outright cheating: “Some of the potassium results at Theranos were so high that patients would have to be dead for the results to be correct, according to one former employee.”

Company counsel replied that “Theranos has no indication that ‘inaccurate results were returned to patients.’”

The technology is also in question: It appears that Theranos uses its “breakthrough” Edison device in only one of the tests it sells. For everything else, it uses commercially available machines.

Holmes emphatically disagrees with the Wall Street Journal, calling its reports “factually and scientifically erroneous and grounded in baseless assertions,” without offering fresh data on the accuracy and repeatability of its tests.

Again…whom should I believe?

Holmes’ story is quintessential Silicon Valley. A Stanford drop-out who learned Mandarin and then sold C++ compilers to Chinese universities, Holmes holds more than a dozen patents, is financed by prominent venture investors, and has ascended to the financial pinnacle (Theranos, still private, is said to be worth $9 billion, of which Holmes would own about $4.5 billion). She’s lionized by an adoring media—see Ken Auletta’s New Yorker profile, and Inc. Magazine’s “21 Surprising Facts About Billionaire Entrepreneur Elizabeth Holmes.” She wears black turtlenecks and is inevitably compared with, well, you know…

Digging a bit deeper, Theranos’ board of directors makes me squirm—it includes former secretaries of state George Schultz and Henry Kissinger, former secretary of defense William Perry, and an erstwhile US Senator (Sam Nunn). How can these people help with innovative healthcare technologies and business models?

To settle questions of integrity, Theranos could take a large sample of patients (the company claims to have administered “millions” of tests) and compare their numbers to Quest Diagnostics or Stanford results on the same patients… I’ll volunteer.

The exercise might look costly, but consider the alternative: Angry FDA regulators, lawsuits (Theranos already hired famed attorney David Boies as a preemptive measure), and, ultimately, the end of a dream.

This post originally appeared at Monday Note.

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