The pediatric patient was closely cared for and monitored during the post-transplant period.
A Girl with the Most Severe Form of Inborn Errors of Immunity
Having suffered from a serious illness since just four months after birth, baby girl T.L., 18 months old, from Hai Phong, began experiencing episodes of pneumonia and had to be hospitalized for long-term treatment. During this time, the child’s immune system continuously faced serious problems, including a complication of swollen axillary lymph nodes after receiving the tuberculosis vaccine.
In August 2024, her family took her to the National Children’s Hospital for examination and specialized immunological and genetic testing. The results confirmed that she had severe combined congenital immunodeficiency caused by a rare gene mutation.
Dr. Nguyen Thi Van Anh, Deputy Head of the Department of Immunology, Allergy and Rheumatology at the National Children’s Hospital, said that T.L. had the most severe form of inborn errors of immunity — Omenn syndrome. The condition causes severe deficiency of lymphocyte cell lines, making children highly susceptible to serious infections, while also triggering autoinflammatory reactions in the body, resulting in generalized red skin lesions, organ damage, and persistent elevated liver enzymes.
In addition to isolation and the use of antibiotics against bacteria, fungi, tuberculosis, and viruses, the child also had to take immunosuppressive drugs to reduce autoinflammatory reactions. Therefore, urgent preparation for hematopoietic stem cell transplantation was carried out. This is an extremely important treatment that can help the child’s immune system fully recover.
T.L. can now play freely and smile like a healthy child.
After a hospital consultation chaired by Dr. Cao Viet Tung, Deputy Director of the National Children’s Hospital, doctors determined that hematopoietic stem cell transplantation was the urgent path needed to save T.L.’s life. However, this treatment phase was extremely stressful, as the child had severe infection and liver damage and at one point seemed unlikely to survive.
With the determination of doctors and medical staff, after numerous consultations and multidisciplinary coordination among immunology, respiratory, hepatobiliary, intensive care, and stem cell specialists, by July 2025 the child’s overall condition had become more stable and she was ready for stem cell transplantation.
Overcoming Challenges in Stem Cell Transplantation for Young Children
Dr. Nguyen Ngoc Quynh Le, Head of the Stem Cell Transplantation Department at the Stem Cell Center of the National Children’s Hospital, said that the stem cell transplantation process in young children is particularly complex. First, the pediatric patient must undergo a conditioning phase with a specific chemotherapy regimen to eliminate the old bone marrow and prevent rejection.
For children under one year old, chemotherapy is extremely challenging because their bodies are still immature, their ability to tolerate medication is poor, and the risk of complications is high.
At the Stem Cell Center, after bone marrow was collected from the patient’s older sister, it was processed using a modern equipment system under a strictly sterile procedure. This process was carried out urgently, and in less than one hour, standard-quality stem cells were ready to be infused into the child’s body.
Directly performing the transplant, Dr. Nguyen Ngoc Quynh Le said that stem cell transplantation in young children is a major challenge, especially for a patient with a very severe infection like T.L. It requires not only modern techniques but also close coordination among specialties, including respiratory intensive care, nutrition, infection control, blood transfusion, and immunology. Every step in the transplant room must be absolutely precise to ensure the patient’s safety.
After the transplant, T.L. was treated in a completely sterile room, nourished through intravenous feeding, given new-generation anti-rejection medication, closely monitored, and underwent daily hematological and immunological testing.
There were periods when the child developed severe pneumonia and bloodstream infection, requiring invasive mechanical ventilation, along with multiple strong antibiotics to control the infection. However, thanks to the tireless efforts and determination of the medical team throughout the care and resuscitation process, T.L.’s new bone marrow cells developed, her blood indicators stabilized, and a new immune system was formed.
To date, T.L. can breathe on her own, breastfeed, smile, and play like a healthy baby, and she has been discharged from the hospital. Doctors assess her prognosis as positive, and after returning to daily life, she can fully develop normally like other children.
The leadership board and doctors of the Stem Cell Center happily see the pediatric patient off as she is discharged from the hospital.
Moved to see her child overcome the critical condition and become healthy again, T.L.’s mother tearfully shared that this happiness could not be expressed in words. “The doctors brought my child back from the hands of death. Seeing her able to play, smile, and talk again is a priceless gift. Our family is deeply grateful to the Hospital Board of Directors, the doctors of the Stem Cell Center, and the Department of Immunology, Allergy and Rheumatology. They have always accompanied, supported, and helped our child and family throughout nearly the past year,” the patient’s mother said emotionally.
Amid the reality that inborn errors of immunity in children are increasing while most cases are not detected and treated in time, T.L.’s story is clear evidence of the importance of early diagnosis and the progress of stem cell transplantation applications in medicine.