There seems to be an app for everything, and now there’s a non-invasive way to detect anaemia via a smartphone app
Instead of a blood test, biomedical engineers have developed a smartphone app that uses photos of someone’s fingernails to accurately measure how much haemoglobin is in their blood.
No more needles or blood
“All other ‘point-of-care’ anaemia detection tools require external equipment, and represent trade-offs between invasiveness, cost, and accuracy,” says principal investigator Wilbur Lam, MD, PhD. “This is a standalone app whose accuracy is on par with currently available point-of-care tests without the need to draw blood.”
Lam is associate professor of paediatrics at Emory University School of Medicine and a clinical haematologist.
Researcher motivated by his disease
The app is part of the PhD work of former biomedical engineering graduate student Rob Mannino, PhD.
Mannino was motivated to conduct the research by his own experience living with beta-thalassemia, an inherited blood disorder caused by a mutation in the beta-globin gene.
“Treatment for my disease requires monthly blood transfusions,” Mannino says. “My doctors would test my haemoglobin levels more if they could, but it’s a hassle for me to get to the hospital in between transfusions to receive this blood test. Instead, my doctors currently have to just estimate when I’m going to need a transfusion, based on my haemoglobin level trends.”
“This whole project couldn’t have been done by anyone but Rob,” Lam says. “He took pictures of himself before and after transfusions as his haemoglobin levels were changing, which enabled him to constantly refine and tweak his technology on himself in a very efficient manner. So essentially, he was his own perfect initial test subject with each iteration of the app.”
It could help people with chronic anaemia
Mannino and Lam say that their app could facilitate self-management by patients with chronic anaemia.
It would allow them to monitor their disease and to identify the times when they need to adjust their therapies or receive transfusions, possibly reducing side effects or the complications of having transfusions too early or too late.
A good app for pregnant women
Although the app should be used for screening and is not a clinical diagnosis, the technology could be especially appropriate for pregnant women, women with abnormal menstrual bleeding, or runners/athletes.
What is anaemia?
Anaemia is a blood condition that affects two billion people worldwide and can lead to fatigue, paleness and cardiac distress if left untreated.
The current gold standard for anaemia diagnosis is known as a ‘complete blood count’ (CBC).
How accurate is the app?
The researchers studied fingernail photos and correlated the colour of the fingernail beds with haemoglobin levels measured by CBC in 337 people, some healthy and others with a variety of anaemia diagnoses.
The algorithm for converting fingernail colour to blood haemoglobin level was developed with 237 of these subjects and then tested on 100.
A single smartphone image, without personalised calibration, can measure haemoglobin level with an accuracy of 2,4 grams/decilitre with a sensitivity of up to 97 percent.
Personalised calibration, tested on four patients over the course of several weeks, can improve the accuracy to 0,92 grams/decilitre, a degree of accuracy on par with point-of-care blood-based haemoglobin tests. Normal values are 13,5 to 17,5 grams/decilitre for males and 12,0 to 15,5 grams/decilitre for females.
In the app, the use of fingernail beds, which do not contain melanin, means the test is valid for people with a variety of skin tones. The accuracy is consistent for dark or light skin tones, Mannino says.
The app uses image metadata to correct for background brightness and can be adapted to phones from multiple manufacturers.
The smartphone anaemia app is projected to be available commercially for public download as soon as the first half of 2019.
Source: Emory Mory Health Sciences via EurekAlert