Short wait times, long-term survival in young children receiving lung transplant

Key takeaways

• Compared with patients aged 3 years and older, younger patients had shorter lung transplant wait times.
• Children aged younger than 3 years receiving a transplant showed more morbidity.

Children aged younger than 3 years receiving a lung transplant have different diagnoses, shorter wait times and comparable long-term survival to older patients, according to a study published in Annals of the American Thoracic Society.

“Carefully selected infants and young children with end-stage lung and pulmonary vascular disease are appropriate candidates for lung transplantation and are likely underserved by current clinical practice,” Ernestina Melicoff, MD, assistant professor in the section of pediatric pulmonology at Baylor College of Medicine and medical director of the lung transplant program at Texas Children’s Hospital, and colleagues wrote.

In a retrospective review, Melicoff and colleagues analyzed 36 infants/children aged younger than 3 years between 2002 and 2020 who received a lung transplant at Texas Children’s Hospital to address diagnosis, wait time and mortality in this age group of patients since children that fall in this age range rarely receive transplants worldwide, according to researchers.

Researchers compared these patients with 192 children aged 3 years and older who also received a transplant at Texas Children’s Hospital during that timeframe. Older transplant recipients from this program were also included for comparison.

Of the cohort of those aged younger than 3 years, four patients were aged 2 to 3 years, 10 were aged 1 to 2 years and 22 were aged younger than 1 year at the time they received a lung transplant.

Diagnosis, referral, wait times

Compared with the older cohort, researchers found that the younger cohort had different and unique underlying diseases. Fifteen children aged younger than 3 years had surfactant dysfunction disorders, which is an uncommon diagnosis in older patients, according to researchers. Other diagnoses in this cohort included bronchopulmonary dysplasia (n = 5), FLNA (filamin A) mutation with progressive respiratory failure (n = 6), primary pulmonary vascular disease (n = 4) and miscellaneous disorders (n = 6).

Additionally, none of the children in the younger cohort had cystic fibrosis, a regularly reported diagnosis in older patients, researchers noted.

When looking at referrals, fewer of those aged younger than 3 years were referred (30% vs. 70%) and listed for transplantation (17.2% vs. 38.8%) compared with the older cohort.

In terms of wait time, researchers found that patients aged younger than 3 years experienced less waiting than older patients (median ± standard deviation, 32 days ± 26.3 vs. 66 days ± 105.8; P < .0043). Researchers also noted that the wait time found for the younger cohort is lower than national averages.

Accounting for ages ranging from less than 1 year to 18 years and older, those younger than 1 year had the shortest median wait time of 26 days, followed by 1- to 3-year-olds (35.5 days), 12- to 17-year-olds (42 days), 18-year-olds and older (54 days) and 3- to 12-year-olds (78 days).

Morbidity, mortality

When assessing anesthetic and surgical approaches taken in younger and older recipients, researchers said there are no differences. However, lung function testing after transplantation does differ between ages since the Texas Children’s Hospital program does not use this test when examining patients aged younger than 5 years.

Compared with the older cohort, researchers observed that more patients aged younger than 3 years were in the ICU when they received their transplant (12 patients vs. 32 patients), had tracheostomy tubes (5 patients vs. 24 patients) and were on extracorporeal membrane oxygenation before transplantation (2 patients vs. 5 patients), showing greater morbidity.

Within 1 year following transplantation, researchers observed a low incidence of allograft rejection with only 2 patients in the younger cohort needing treatment.

In terms of death after transplantation, researchers observed comparable survival at 1 year between those aged younger than 3 years and the older cohort (87.9% vs. 89.6%).

Further, researchers wrote that 5-year survival rates are similar among those aged younger than 3 years and those in the overall program. Importantly, the younger patients show “enduring survival” over succeeding years compared with the overall cohort in which there is steady mortality.

Looking at time periods of transplantation, higher early survival in infant and young children recipients has been found between 2011 to 2019 than between 2002 to 2010, according to researchers.

Following transplantation, 13 children (39%) aged younger than 3 years died, with the main causes being bronchiolitis obliterans (n = 5) and viral pneumonia (n = 5). The remaining causes occurred in one child each: status epilepticus, multiorgan failure and early death with primary graft dysfunction. Most of these deaths took place less than 3 months following the transplantation (n = 4) or in the second year (n = 4).

“We believe that the practicality and availability of lung transplantation in infants and young children are not sufficiently appreciated or embraced within the neonatology, pediatric critical care, and even pediatric pulmonology communities,” Melicoff and colleagues wrote. “We hope that this manuscript will address this insufficiency. Our experience has shown that, in our hands, these patients can be managed before and after transplantation, the wait time can be quite short, mortality while waiting is not necessarily high, and survival and long-term outcomes have improved over time.”