How Do People With Type 1 Diabetes Monitor Beta Cell Function?

When Kylie Grimes’ 7-month-old son, Noble, came down with walking pneumonia in April, she thought she was in for a tough but temporary hospital stay. Instead, her family’s life turned upside down.

Noble was vomiting, severely dehydrated, and showing signs of Kussmaul (deep, rapid, continuous breathing) – a red flag for diabetic ketoacidosis (DKA). He was slipping into a diabetic coma before anyone had even uttered the words “type 1 diabetes” to his parents.

“It’s hard to catch diabetes in infants,” Kylie recalled. “Frequent urination, irritability, always wanting to nurse – those could be symptoms, but they could also just be a baby being a baby.”

Noble spent eight days in the hospital. When the diagnosis of type 1 diabetes finally came, Kylie felt an odd sense of relief. After spending multiple days thinking her child’s life was at risk, diabetes felt doable. 

But learning to “do diabetes” for a baby was an entirely different challenge. 

“All the training about diabetes doesn’t apply to a baby,” Kylie said. “Even in the hospital, the healthcare providers had difficulty treating his lows, and he was always being overdosed with insulin.”

After he was stabilized, Noble was sent home with two types of insulin: basal insulin twice daily for baseline coverage and diluted rapid-acting insulin up to 10 times a day for meals and corrections. He wears a continuous glucose monitor (CGM), but is still too young for an insulin pump or an automated insulin delivery (AID) system. 

In the hospital, doctors ran autoantibody tests on Noble. At first, he tested positive for just one of the five known diabetes-related autoantibodies. However, later testing showed he was positive for all of them.

A second diagnosis

Just 63 days after Noble’s diagnosis, Kylie’s 6-year-old daughter, Goldie, was playing with her brother’s blood sugar monitor when she pricked her finger and her reading came back at 416 mg/dL. At first, Kylie thought the sensor was broken. But after testing it on multiple people and checking it against Noble’s CGM, Kylie took Goldie to the hospital. 

“The endocrinologist walked into the room and gave me a hug,” she said. “It was type 1.”

Goldie tested positive for four out of the five autoantibodies. 

How autoantibody testing works

Autoantibody tests are typically simple blood draws that look for the five markers linked to the development of type 1 diabetes. 

Through TrialNet, Kylie and her family were able to test everyone. Because Goldie has stage 2 type 1 diabetes, she can get free monitoring and blood draws through TrialNet until she reaches stage 3, her younger brother Noble’s stage – and the stage where insulin is needed.

“The process was really easy,” Kylie said. “The blood draw took 20 minutes. It was fast, painless, and it gave us answers within a few weeks.”

Programs like TrialNet make testing accessible, especially for family members of people with type 1 diabetes.

Why autoantibody testing matters

Autoantibody testing is a critical tool for understanding and monitoring beta cell function, which tells you the ability of the pancreas to still produce insulin. In people with type 1 diabetes, the immune system mistakenly targets insulin-producing beta cells; the presence of these autoantibodies signals that this attack is underway.

Catching type 1 diabetes early matters because at diagnosis, about 20% of beta cells are often still functioning. That early period is vital because once those remaining cells are lost, they’re gone for good. Preserving function, even temporarily, means fewer swings in blood sugar, lower risk of DKA, and more time for families to learn about insulin management. 

For Kylie and her husband, who don’t have type 1 themselves, it was a shock to see two of their four children diagnosed. This serves as a reminder that diabetes doesn’t always follow a clear hereditary path, making broader screening that much more important.

Types of antibody tests

Staging type 1 diabetes is complex because multiple factors are taken into consideration. These include fasting blood sugar, results from an oral glucose tolerance test (OGTT), and A1C. 

According to the American Diabetes Association (ADA), the presence of two or more autoantibodies is a near-certain predictor of type 1 diabetes. The ADA recommends screening for the following autoantibodies in individuals with a family history of type 1 diabetes or other autoimmune disorders. 

Insulin autoantibodies (IAA)

These are usually the first autoantibodies to appear in young children, sometimes even before age 2. A positive IAA result means the immune system is attacking insulin itself. Since insulin is critical for regulating blood sugar, this test can be an early warning sign. IAA testing is especially important for infants and toddlers, where symptoms of diabetes can be difficult to recognize.

Glutamic acid decarboxylase autoantibodies (GADA)

These autoantibodies target an enzyme inside beta cells. GAD antibodies are also commonly seen in children up until age 15, but adult-onset cases can also present with GAD autoantibodies. These are associated with a slower progression to type 1 diabetes.

Insulinoma-associated-2 autoantibodies (IA-2A)

These target proteins in the insulin-producing cells themselves. A positive result suggests the immune system is actively attacking beta cells, which may mean diabetes is developing more quickly. A positive IA-2A result may mean faster progression to stage 3 type 1 diabetes.

Zinc transporter 8 autoantibodies (ZnT8A)

Discovered more recently, ZnT8 antibodies are present in many people who develop type 1 diabetes, but not always in isolation – these autoantibodies often appear alongside the others. ZnT8 testing can catch cases that might be missed if only older antibody tests are used.

Finding support in the Wild West

While screening recommendations and medical textbooks offer guidance on how to monitor beta cell function, real life doesn’t always play along. In Kylie’s unique case, her youngest son went through a life-threatening hospital stay before a diagnosis was even on the table. Yet her daughter, who didn’t experience any symptoms for six years, was diagnosed by pure chance.

Kylie’s advice to other parents who may be experiencing a similar situation: “Trust your gut, and be kind to yourself. Even adults living with diabetes for decades don’t have it completely figured out.”

Her husband added that community has been essential. “Diabetes is scary. It’s lonely, it’s the Wild West – you have no clue what to do. Finding a community or anybody that has some kind of experience that you can talk to makes all the difference.”

Kylie and her family have found this community through social media, where she shares their family’s journey with type 1 diabetes on Instagram. In addition, they have launched a GoFundMe to help cover the costs of a diabetic alert dog for their son, Noble.

With support from their family, care team, and the wider type 1 diabetes community, both Noble and Goldie are adjusting to life with diabetes.

The bottom line

Diagnosing type 1 diabetes before the onset of symptoms can help preserve remaining beta cell function – meaning the body can still make some of its own insulin, which is far more effective at regulating blood sugar than insulin given by injection. 

For families like Kylie’s, autoantibody testing offers more than numbers. It can bring clarity in the middle of chaos. Knowing where you stand allows parents and healthcare providers to act early, prepare, and find community in a journey that is often unpredictable. Their story is an important reminder to advocate for yourself – and to get screened early.

Learn more about screening and diagnosing type 1 diabetes here:

• From Uncertainty to Empowerment: The Journey in Type 1 Screening
• Can You Pass Diabetes on to Your Children?
• Screening and Prevention of Type 1 Diabetes