If your child’s pituitary gland doesn’t make enough growth hormone, they have a condition called pediatric growth hormone deficiency (pGHD). It’s not only their height that can be affected, but their metabolism (energy levels) and heart and bone health.
pGHD is a rare condition. Only about 1 in every 3,000 to 10,000 children have it. But the sooner that it’s diagnosed, the sooner it can be treated.
Here’s a look at how doctors can diagnose and treat pGHD now — and what improvements are on the horizon.
New Insights Into pGHD Diagnosis
pGHD can be tricky to diagnose.
“There's not one test that you can do that says, ‘Oh yes, you definitely have growth hormone deficiency,’” says Carmen Soto-Rivera, MD, director of the Neuroendocrinology and Cancer Survivorship Program at Boston Children’s Hospital. “Even our gold standard testing, which is the growth hormone stimulation test, can be unreliable.”
Growth hormone (GH) is released from the pituitary gland in pulses, or short bursts, and usually at night. In between, your levels are so low that a blood test usually can’t detect it.
When your child has a growth hormone stimulation (GHS) test, they’re given a medicine that causes GH to be released. Then their blood is taken at a few different times to try to catch it when it peaks.
Doctors also have to rely on information gathered from different sources, like:
- Your child’s physical exam
- How your child is growing
- Other information from your child’s health and family history
- Different blood tests
- Imaging tests like MRIs
In the future, reaching a pGHD diagnosis may become simpler.
“New directions for accurate diagnoses involve how we use these tools together, for example, taking into account the relationship between two of the most commonly used blood tests rather than looking at them individually,” says Iris Gutmark-Little, MD, director of the Growth Center at Cincinnati Children’s in Cincinnati, Ohio.
That may make it easier on kids, too.
“The growth hormone stimulation test, in itself, is a long test. At our institution, we do two tests in a row so you have to be there for six hours getting blood drawn. It's pretty intense. It might make you nauseous, and some kids throw up. It's not very pleasant,” Soto-Rivera says. “So hopefully, in the future, we might see better ways of diagnosing that [kids] don't need to be put through all this testing.”
Will AI Play a Part?
In the future, AI may have an important role in helping doctors see a child’s abnormal growth patterns or spot early pGHD symptoms.
“I don't think that AI can replace what we do,” says Soto-Rivera. “You really need to examine the patient and see if there's anything that would lead you to think that there's a genetic problem or a physical problem. … But at least in looking at patterns and medical records, hopefully it'll make our job a little bit easier.”
New Insights Into Treatments
PGHD can be treated with recombinant growth hormone (rGH), a lab-made version of the growth hormone that your body naturally makes. It’s given in a daily shot, and treatment often lasts several years.
“It's very well tolerated for most kids,” Soto-Rivera says, “but it's still a lot to put on parents. You’re giving an injection every day.”
Newer versions of lab-made GH are longer-acting and only need to be given by shot once a week. They include:
- Lonapegsomatropin (Skytrofa)
- Somapacitan (Sogroya)
- Somatrogon (Genryzon, Ngenla)
So far, data shows that these weekly treatments appear to work as well as the daily injections. “They also seem to have similar risks, but because these are newer, more time is needed to be more certain that the risks and benefits are the same,” says Gutmark-Little.
When your child is healthy, they release pulses of growth hormone every night during sleep. The daily dose of synthetic GH tries to mimic this pattern. The long-acting versions provide a bigger dose that might stay higher at first in your child’s body, then decrease over the course of a week.
“We just don't know whether that makes any difference in the physiology or on the safety profile 40 years from the start,” Soto-Rivera says. “We need to have more experience and more data.”
In the meantime, drugmakers keep searching for new pGHD treatments. These include medications taken by mouth that may encourage the body to release more of its own growth hormone. For instance, LUM-201, also known as ibutamoren, is currently in phase 3 clinical trials. So far, it’s been studied in over 150 children with pGHD and appears to be generally well-tolerated.
“It’s likely going to be several more years before these [types of medications] are available, but this will depend on their efficacy and safety in the ongoing trials,” Gutmark-Little says.
Genetic Testing
Researchers are also learning more about which genes define height.
“It's not like, ‘This gene will tell how tall you're gonna be.’ It's a mix of a lot of genes, and we're learning about mutations that would cause you to grow differently than your family,” says Soto-RIvera.
In the next decade, doctors may be able to more precisely know how tall your child may grow, or the change in height you can expect if they’re treated with growth hormone.
“For now, [genetic testing] only changes clinical management for a small subset of patients,” says Soto-Rivera. “But as we learn more about the genetics of height and of growth hormone deficiency, we should be able to move toward more precise, individualized treatment.”
What’s on the Horizon?
Doctors are optimistic about what may lie ahead for PGHD treatment.
“I hope to be able to offer an alternative for each family and patient that really individualizes therapy and meets both the clinical goals of treatment and fits into family life with minimal disruption,” says Gajan Muthuvel, MD, a pediatric endocrinologist at Cincinnati Children’s Hospital Medical Center.
More options benefit not just kids, but families.