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One-Year Anniversary: The Jeffrey Modell Diagnostic and Research Center at MUSC Health Excels at Helping Patients with Rare Immunodeficiencies

MUSC Children's Health
November 30, 2022
Dr. Kelli Williams speaking with another care team member.

By Matthew Greseth, Ph.D.

Heather Mahoney had a typical pregnancy, but during a visit back home to Boston, she went into labor early. She delivered a healthy baby girl, Isabella, but her newborn screening showed some concerning results.

There was initial concern that Bella had severe combined immunodeficiency (SCID), a group of rare disorders that affects the development and function of immune cells. While infants diagnosed with this condition can appear healthy at birth, they are highly susceptible to infections.

Bella spent her first two months in Boston Children's Hospital where follow-up genetic testing revealed that she actually had an extremely rare combined immunodeficiency called Rac2 deficiency, in which a critical protein, Rac2, doesn't function properly in immune cells. There are roughly 50 patients with this diagnosis worldwide.

In order to come home to Charleston, Bella would need a sophisticated center to treat and follow her. Luckily for the Mahoneys, Charleston is home to the Jeffrey Modell Diagnostic and Research Center for Primary Immunodeficiency Diseases at MUSC Health, which was able to ease the Mahoney's worry and help them to manage Bella's rare immunological condition.

"It's been a wild, emotional roller coaster, and I thank God for MUSC," said Heather Mahoney. "They have been so amazing and have followed her so closely."

A Year in the Making

At the beginning of 2022, the MUSC Health Immunology Center was renamed the Jeffrey Modell Diagnostic and Research Center for Primary Immunodeficiencies, after receiving international distinction that placed MUSC Health among a select group of go-to locations for patients with rare immunologic conditions. The Jeffrey Modell Foundation (JMF) network consists of over 400 programs at academic medical institutions worldwide (only 42 centers in the US) and focuses on helping children and adults with rare immunological diseases known as inborn errors of immunity. Some rare conditions that fall into this category include SCID, DiGeorge Syndrome, common variable immune deficiency (CVID) and hypogammaglobulinemia, or low antibody levels.

The center is led by Kelli Williams, M.D., an associate professor in the Department of Pediatrics at the Medical University of South Carolina, who sub-specializes in pediatric allergy and immunology. Williams said this recognition has presented an extraordinary opportunity to establish a center on par with the cream-of-the-crop programs in the world.

"Since we received recognition from the JMF, more people on campus are aware of what we do and are now thinking about immunology and immunological diseases in a different way," said Williams. "I think this has been amazing for our program."

Since 2015, when Williams came to MUSC, the clinic has been busy helping patients. But receiving the special designation from the JMF gave the clinic even more credibility and has led to a significant and exciting increase in referrals.

"It's really opened a lot of doors and more collaborations with institutions across the country," said Williams. "We now work with people all around the world to better characterize certain rare immunologic diseases, which has been great. Great for our patients. Great for our research. Great for our diagnostics."

And she should know. Williams previously trained at the National Institutes of Health, where she worked with patients, both children and adults, who had rare immunologic and allergic diseases. Because this was her passion, she knew she wanted to work in a setting where the level of clinical care and research was of the highest caliber. MUSC made that opportunity possible.

"Everything I've done since coming in 2015 has been a concerted effort to offer better care for those complex immunology patients," said Williams, and that included applying to the JMF and receiving its distinguished designation.

"It's really changed the way I feel that we are able to offer care to our patients and has been eye-opening for the institution to show them we're providing top-notch care for these patients, but we can do even better."

Patient Impact

Just after Bella's diagnosis and arriving at MUSC, Williams monitored her very closely due to her severely immunocompromised state, often once a week. One of the consequences from Bella's condition is having very low T-cell numbers – cells that fight infections. This puts her at a high risk for infections – even a simple respiratory virus could send her to the hospital.

Williams was in constant communication with the Mahoneys, ensuring that everyone was on the same page. Together, they crafted a specific care plan for Bella's rare immunologic condition based on Williams' expertise. Over time, Bella's immune system slowly improved, and Williams told the Mahoneys the good news.

"It was a really magical moment. Our family was visiting when we got the results back," recalled Heather Mahoney. "I put her on speaker phone, and she told us that Bella's tests came back, and her immune cell function had gone up."

While Bella continues to have some problems with her B-cells, or antibody producing cells, and neutrophils, which are first responders to some specific infections, her T-cell problem has completely resolved. Williams believes that Bella is the first case of in which her Rac2 deficiency has begun to revert back to normal. She is also working to better characterize how Bella's immune system has changed over time.

Isabella Mahoney, who was treated at Jeffrey Modell Diagnostic and Research Center for Primary Immunodeficiency Diseases at MUSC Health. 
Isabelle Mahoney

"Bella is still partly immunocompromised and requires home infusions to boost her immune system, but she is not as sick anymore and rarely gets hospitalized, which is wonderful," said Williams. "Now I see her every four to six months because she is generally much better."

"I absolutely love Dr. Williams. She is so thorough, and I am so grateful we have her," exclaimed Heather Mahoney. "She is so knowledgeable, and we are truly blessed to have such a great team."

Things have continued to improve for Bella. She is a bright and charismatic 4-year-old who lives a normal – but careful – life and is now attending school.

"It's been quite a journey, but today she is thriving and doing well," said Heather Mahoney.

What the Future Holds

Over the past few years, Williams has treated many rare and complex patients in the Charleston area. The JMF designation has only increased the number and types of patients that now come to the center. Williams and her small but enthusiastic team are excited to continue expanding their impact across the state.

"I'm hoping to continue to build a really strong foundation for our center so we are continuing to handle all of the referrals but also expand our center from a focus standpoint," said Williams.

Patients often come from across the region to the center to receive care. Depending on their types of treatments, they may need to visit MUSC frequently. To make treatments easier for these patients, the center is partnering with local physicians and specialty pharmacies to manage care either at other centers or at patients' homes via telehealth. This significantly helps patients who have to travel and enables them to come to MUSC only a few times a year.

As the center continues to grow, Williams and her team hope to design multi-specialty care clinics to focus more on specific types of disorders, testing and treatments and to foster an interdisciplinary approach to treating these complex patients.

Genetic testing, though necessary, can be cost prohibitive for many patients and the JMF is able to provide some resources to help mitigate these costs. Despite these potential cost barriers, more and more patients are seeking genetic testing. To help patients to navigate what this new genetic information means for them and how it will affect their families, the center is hoping to add a part-time genetic counselor to the team.

"I'd like to think the majority of our patients have benefited from our center," said Williams. "I hope that I can continue to lay a really strong foundation and continue our efforts to make patients feel well-cared for."