Genetics in the News
Elizabeth Whiting Magg, NBSN2006, Main Campus, Fall 2015
Unique Combinations of Racial Heritage Present Transplant Problems
Racial disparities in healthcare outcomes are well known, and are often the outcome of overt or subconscious discrimination. However, there are cases where race can present a challenge to care in a totally unique way.
Vicki Ortiz Healy's telling of the plight of Sophia Trujillo highlights how, when it comes to bone marrow transplant, mixed race patients are at a steep disadvantage. Sophia is a child suffering from aplastic anemia. The disease can be fatal, but a bone marrow transplant can greatly increase a patient's odds of surviving. However, bone marrow cells--just like those of other organs--have self markers that determine the success of the transplant.
Human leukocyte antigens (HLAs) are proteins found on cells that allow the body to self-identify. They keep the immune system from attacking normal body cells. In a transplant recipient, the donor HLAs must be a close enough match to the recipient so the recipient's immune system will not attack and reject the transplanted tissue. A major determinant for HLA matching is race. HLAs evolved right along with the rest of human DNA, leading them to be more similar within the populations from which they evolved. This is the challenge facing Sophia, whose unique Filipino-Irish-Spanish-Italian makes it more difficult to find someone whose HLAs are similar enough to be a donor.
This is not a problem unique to the United States. Any society that has a racially diverse population with interracial breeding can experience this issue. In Britain, for example, the British National Party estimates a white Brit seeking a bone marrow match has a 1 in 3 chance of finding it. However, if the patient is of mixed race, that chance drops all the way to 1 in 200,000. It's not just a problem of mixed races. Those of mixed race could even benefit from a more diverse donor pool that would be more likely than the current pool to include a match. In America, 61% of individuals on the bone marrow registry are white. However, targeted efforts to reach minorities and mixed race individuals have been successful in increasing their prevalence in the registry.
At a time when the country is getting more diverse, it will be our job as nurses to understand the unique situation mixed race transplant patients will face. Not only will this enable us to provide better, more compassionate care, but it will mean we understand the importance of diversifying tissue donation registries and can talk to potential donors about whether they may be interested in joining. Knowing real-life stories like Sophia's can make an impact both on healthcare professionals' willingness to disseminate knowledge and potential donors who are weighing costs and benefits of registering.
British National Party. Bone marrow donor disparities reveal reality of race once again. Retrieved from http://www.bnp.org.uk/news/bone-marrow-donor-disparities-reveal-reality-race-once-again
Mavin Foundation. (2006). Matchmaker. Retrieved from http://www.mavinfoundation.org/projects/matchmaker.html
Ortiz Healy, V. (2015 Sept 11). Girl in need of bone marrow highlights shortage of mixed-race donors. Chicago Tribune. Retrieved from http://www.chicagotribune.com/news/ct-bone-marrow-mixed-race-met-20150911-story.html
Understanding Evolution. (2011 Dec). When fighting leukemia, evolutionary history matters. Retrieved from http://evolution.berkeley.edu/evolibrary/news/111101_hla
A Technician Testing HLAs
A Depiction of HLAs on a Cell
How Marrow Transplant is Performed
Chicago Tribune Article Full Text
Girl in need of bone marrow highlights shortage of mixed-race donors
Girl in need of bone marrow highlights shortage of mixed-race donors
Sophia Trujillo, 6, watches as her blood is drawn at Advocate Children's Hospital in Park Ridge on Sept. 4, 2015. She needs a bone marrow transplant, but finding a donor with her racial makeup is difficult. (Jose M. Osorio / Chicago Tribune)
Vikki Ortiz HealyContact ReporterChicago Tribune
"I need to save my kid somehow," Crystal Lake mother vows to find bone marrow match for mixed-race daughter.
When doctors told Michelle Trujillo in July that her 6-year-old daughter would need a bone marrow transplant to save her life, the Crystal Lake mother didn't want to wait another minute before getting her only child back to health.
But months later, Sophia — who has aplastic anemia, a rare disorder that impairs her immunity — is still waiting for a donor match. Meanwhile, Trujillo says she lies in bed at night making mental lists of places to try to find a donor with similar multiracial heritage to her daughter's — a group with a strikingly low match rate.
"I don't sleep at night. I think of, 'What can I do now? Who can I contact now?' " said Trujillo, whose daughter is half Filipino, as well as Irish, Spanish and Italian. "One match is all we need, but it's like a needle in a haystack."
The Trujillos' predicament highlights a nationwide paradox that has troubled medical experts and families awaiting transplants for years: despite the ever-growing diversity in the United States, there are not enough minority and multiracial donors registered and available for patients in need.
In the national bone marrow registry, Be the Match, 61 percent of the donors are white, 10 percent are Hispanic or Latino, 6 percent are black, 6 percent are Asian and just 4 percent are multiple races.
Given these numbers, the likelihood of matching a white patient with a donor is 97 percent. But the chances drop from there: Asians have a 72 to 88 percent chance of being matched; black patients have 66 to 76 percent chance. And while numbers are not available for mixed-race matches, the odds of multiracial patients finding a match are considerably lower, according to Lauren Johnson, Community Engagement Specialist for Be the Match.
Marrow and cord blood contain certain genetic markers that are inherited, and combinations of those markers are more common in some racial groups than others. So, while not a guarantee, a donation from someone with similar racial heritage presents the best possible chance for transplant success, Johnson said.
This is different from the donor matching process for tissue transplants such as hearts, livers and kidneys, when race is not a key factor.
To address the shortage, officials from the national registry — along with hospitals, charity groups and families waiting for transplants — have worked hard to grow the number of minority and mixed-race donors over the last five years. Be the Match representatives have reached out to ethnic community leaders, church pastors, college fraternities and other groups in hopes of diversifying the donor pool, Johnson said.
Despite the efforts, however, growth in those groups remains slow, and medical professionals say the shortage will become more pronounced as the American population gets even more diverse.
"There are people from all over the country, all over the world that are searching for any possible way to help their case — and they're desperate," said Athena Asklipiadis, founder of Mixed Marrow, a not-for-profit website dedicated to spreading the word about mixed-race patients in need of donors.
The group recently promoted the story of Sophia, whose heritage makes her difficult to match. While people of European ancestry tend to be matched quickly, the young girl's half-Filipino side diminishes her chances, said Caitlin Agrawal, one of Sophia's doctors in the department of pediatric hematology/oncology at Advocate Children's Hospital in Park Ridge.
Bone marrow makes the components of blood — white blood cells that fight disease, and red blood cells that carry oxygen and platelets to help stop bleeding. When bone marrow becomes unhealthy, as it does with illnesses including leukemia, aplastic anemia and other genetic or immune diseases, a bone marrow transplant is often a patient's best chance for survival.
A little more than a year ago, Sophia was a seemingly healthy little girl who loved birthday parties, the color pink and singing along with the movie "Frozen." At her annual wellness check, Trujillo mentioned that Sophia seemed to bruise easily. Doctors noted that toddler bruising is common as children play, but they ordered blood tests to be safe, Trujillo said.
Test results detected aplastic anemia, which commonly appears in bone marrow around school age. Her faulty bone marrow stopped making blood cells, and symptoms of the illness — nosebleeds, dizziness and headaches — surfaced over the next year, Agrawal said.
Sophia's aplastic anemia, a life-threatening disease that is estimated to affect two in a million people, means her body stopped making platelets, white and red blood cells. While occasional blood transfusions give her red blood cells and platelets, the white blood cells cannot be replaced, leaving her with a weakened immune system. Her body is unable to clot blood or fight even the common cold, doctors said.
To keep her from infection, she can no longer attend school or her beloved ballet classes. And over time, frequent blood transfusions can cause fatal damage to the liver and heart, Agrawal said.
"Her bone marrow is very sick, but you would never know in seeing her," Agrawal said. "It's as urgent as can be because we don't know when she'll run into an infection she can't fight off."
In the transplant process, her unhealthy blood cells would be wiped out so they could be replaced with properly functioning ones. The cells needed could also come from cord blood saved from a placenta after an infant is born, Agrawal said.
But because of Sophia's unusual racial heritage, no matches — from either bone marrow or cord blood — have surfaced in the national registry since she was diagnosed. The potential donor would not need to be precisely the same percentages of each race to be a good candidate, but the more similar the backgrounds line up, the better the chances of a match, Agrawal said.
At a recent weekly hospital visit, the first grader tensed when nurses announced it was time to inject a needle into a portal device in her chest.
"What if the needle hurts?" the girl asked.
"You know how it is, Sweetie. One, two, three, we just be brave and count," the nurse said.
"Just don't squeeze that hard," Sophia responded, taking pride in helping the nurses to pull off each tube as they filled with her blood as part of regular tests to make sure her cell counts don't dip dangerously low and require a blood transfusion.
Sonali Chaudhury, attending physician for the division of stem cell transport at Lurie Children's Hospital in Chicago, said while medical professionals have long anticipated a future with patients largely from multiracial backgrounds, the shortages in the bone marrow registry demonstrates how that population exists here and now.
"We're sort of seeing the early part of the biracial population that we know we are going to be dealing with down the road," Chaudhury said. "We, as a group of physicians and medical caregivers, have to start thinking about different racial groups."
Chaudhury said she and other physicians have begun urging minority and mixed-race patients to consider becoming bone marrow donors. She also tries to educate patients about donating cord blood when a child is born, a service often available at hospitals but not widely used.
"I feel like I talk about it a lot," Chaudhury said. "I don't know why everyone else isn't talking about it."
Johnson, of Be the Match, said several misconceptions may have contributed to the slow growth in minority and mixed-race marrow donors. Some cultural groups have religious or superstitious hesitations about giving away a part of themselves. Others simply have not been exposed to the concept, or fear it's a painful or very involved process, she said.
In actuality, donating bone marrow is often a simple process similar to giving blood, Johnson said.
In the meantime, Trujillo, an account manager for Eaglewood Resort and Spa in Itasca, has dedicated herself to finding her daughter's match. Working with Be the Match officials, Trujillo has organized several upcoming marrow registry donor drives, including one at Adobofest, a Filipino-American festival Sept. 19 in Morton Grove.
"When you look at her and how she's doing, there's no other way to be than to be strong with her," she said. "At night, I think, 'How am I going to save my kid? I need to save my kid somehow.' "
Twitter @vikkiortiz
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