Two drops of blood

Two Drops of Blood: The Tech Behind Simple CBC

As part of an annual physical exam, a blood test is often performed. From the blood sample that is taken, different tests may be conducted depending on the patient’s medical history, age, and any health concerns they may have. However, the one basic test that is nearly always performed is a complete blood count, or CBC.

This simple test gives a count of the different cells and components circulating in the patient’s blood, including white blood cells, red blood cells and platelets. This provides an important snapshot into an individual’s health, as too many or too few of a given cell type can be an indication of anemia, infection, or even certain types of cancer like leukemia. If anything appears abnormal, further testing is usually required, but it all starts with a humble CBC.

The limitations of current CBC testing

When a CBC is requested, typically 3-8 milliliters of blood is drawn into a vial and shipped off to a lab where the CBC is performed. This may not sound like a lot of blood, and losing that much certainly won’t have any negative effect on your body. However, if a vein is difficult to find (as is the case with many elderly patients), the process can require several attempts and lots of prodding, often resulting in painful bruising that can last several days. This can cause significant distress to an anxious patient, and take a substantial amount of time in a doctor’s office.

Similarly, drawing several milliliters of blood from an infant or child can sometimes be challenging for a medical professional, and often quite distressing for both parent and child. What’s more, even though a CBC is a relatively simple test performed by a machine, the results may take several days to come back to the doctor, and potentially even longer to reach the patient.

The technology to revolutionize basic blood draws

Having large, painful blood draws and waiting days for test results may become a thing of the past thanks to some innovative medical technology mixed with a splash of artificial intelligence. Not so long ago, a CBC was performed by a technician in a lab, who would receive your blood sample, put a drop of it on a microscope slide, stain it with various chemicals to distinguish between different cell types, and then count and analyze the cells under a microscope. Today, most pathology laboratories have complex CBC-reading machines that offer much more rapid results, though the machines themselves are still cumbersome.

Sight Diagnostics, an Israeli startup specializing in computer-vision and machine-learning for medical technologies, are looking to revolutionize the field of basic blood analysis. The group has recently developed a tabletop machine (smaller than a microwave and affectionately known as “OLO”) that can deliver a CBC result in less than 10 minutes, from just two drops of blood. The blood is placed in a disposable clip, which is inserted into the analyzer, where the magic happens. OLO digitizes blood samples into images, then uses computer vision algorithms to identify and quantify the number and type of different blood cells and components in a given sample. Sight has closed a $27.8 million Series C funding round, and recently gained FDA approval for the use of OLO in the United States.

What could this mean for healthcare?

The implications of this could be staggering – your doctor could perform a simple CBC at every visit and would have a much-improved indication of your overall health. Conditions such as anemia may be detected and treated rapidly, eliminating the need for a follow-up visit or phone call to discuss the results. Similarly, the CBC of a coughing patient may show an elevated white blood cell count, indicating a bacterial infection that can be treated with antibiotics. The prescription can be written on the spot, saving the patient days of feeling unwell and potentially infecting others while they wait for a diagnosis.

What’s more, the tiny amount of blood required can be obtained through a simple prick of the finger, making it a far more friendly alternative for elderly patients, babies, and the somewhat faint of heart.  The almost-instant results could be interpreted by and discussed with your doctor in real-time, with follow-up testing ordered on the spot if required. Patients can save time, money, and if necessary, be directed to the relevant specialist more efficiently.

Is any of this sounding familiar?

If you have an eerie sense of déjà vu, it may be because you remember Theranos – the Silicon Valley start-up making a blood analyzer that could perform over 200 common blood diagnostic tests, from just a single drop of blood. Does that sound too good to be true? Well, it was. Despite raising $900 million and catching the eye of investors everywhere, the company ultimately couldn’t deliver. In fact, nobody is sure whether or not they even came close, and CEO Elizabeth Holmes now faces conspiracy and fraud charges.

In reality, the technologies behind Theranos and Sight Diagnostics don’t have much in common. Sight Diagnostics hasn’t developed the technology to perform 200+ blood tests from a single sample. Their focus is on creating a smarter, faster CBC – an achievable deliverable that could have dramatic implications when it comes to modern healthcare systems worldwide. Most importantly (and unlike Theranos), it’s backed up by real science and shows genuine promise.