Georgia Tech's Wilbur Lam Develops
Anemia Detection Via Smartphone
December 19, 2018
engineers have developed a smartphone app with the aim of non-invasive
detection of anemia. Instead of a blood test, the app uses photos of
someone’s fingernails taken on a smartphone to determine whether the
level of hemoglobin in their blood seems low.
The researchers published their results on Tuesday, December 4, 2018, in
“All other ‘point-of-care’ anemia detection tools require external
equipment, and represent trade-offs between invasiveness, cost, and
accuracy,” said principal investigator Wilbur Lam. “This is a standalone
app that can look at hemoglobin levels without the need to draw blood.”
The app should be used for screening, not clinical diagnosis.
Lam is a clinical hematologist-bioengineer at the Aflac Cancer and Blood
Disorders Center of Children’s Healthcare of Atlanta, associate
professor of pediatrics at Emory University School of Medicine and a
faculty member in the Wallace H. Coulter Department of Biomedical
Engineering at Georgia Tech.
The study's first author was Rob Mannino, who 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.
Mannino was a graduate research assistant in biomedical engineering who
has since graduated.
“Treatment for my disease requires monthly blood transfusions,” Mannino
says. “My doctors would test my hemoglobin 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 hemoglobin
“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
hemoglobin 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.”
The app could facilitate self-management by patients with chronic
anemia, allowing them to monitor their disease and to identify the times
when they need to adjust their therapies or receive transfusions, the
researchers said. That may reduce side effects or complications of
having transfusions too early or too late.
The technology could be used by anyone at any time and could be
especially appropriate for pregnant women, women with abnormal menstrual
bleeding, or runners/athletes. Its simplicity means it could be useful
in developing countries. Clinical diagnostic tools have strict accuracy
requirements, but Mannino and Lam think that with additional research,
they can eventually achieve the accuracy needed to replace blood-based
anemia testing for clinical diagnosis.
Anemia 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 anemia diagnosis is known as a
complete blood count (CBC).
The researchers studied fingernail photos and correlated the color of
the fingernail beds with hemoglobin levels measured by CBC in 337
people: some healthy, and others with a variety of anemia diagnoses. The
algorithm for converting fingernail color to blood hemoglobin level was
developed with 237 of these subjects and then tested on 100.
The researchers were able to show that a single smartphone image,
without personalized calibration, can measure hemoglobin level with an
accuracy of 2.4 grams/deciliter with a sensitivity of up to 97 percent.
Personalized calibration, tested on four patients over the course of
several weeks, can improve the accuracy to 0.92 grams/deciliter, a
degree of accuracy on par with point-of-care blood-based hemoglobin
tests. Normal values are 13.5-17.5 grams/deciliter for males and
12.0-15.5 grams/deciliter for females.
In the app, the use of fingernail beds, which do not contain melanin,
means the test can be 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.
Mannino and Lam say they are working with a variety of doctors at
Children’s and Emory – geriatric, internal medicine, neonatologists,
transfusion medicine, global health – to obtain additional data and
better calibrate their system.
“This is just a snapshot of the accuracy right now,” Lam says. “The
algorithm gets smarter with every patient enrolled.”
following researchers co-authored this study: David Myers, Erika
Tyburski, G.D. Clifford of Georgia Tech and Emory; Jeanne Boudreaux,
Christina Carusa of Children's Healthcare of Atlanta, and Traci Leong of
The research was supported by the National Science Foundation (Graduate
Research Fellowship DGE-1650044 and Southeastern Nanotechnology
Infrastructure Corridor 1542174), the 2017 Massachusetts General
Hospital Primary Care Technology Prize, and National Institutes of
Health (R21 EB025646).
The smartphone anemia app is projected to be available commercially for
public download as soon as Spring of 2019. A patent application has been
filed for the anemia app, and Wilbur Lam and Rob Mannino have a
financial interest in the success of this product.