When Growth Hormone Therapy Unexpectedly Triggers Diabetes-Like Crisis

A 13-year-old boy came to the hospital critically ill just two days after receiving his first injection of lonapegsomatropin, a long-acting form of growth hormone. He was experiencing diabetic ketoacidosis (DKA)—a dangerous condition where the body produces too many ketones and becomes too acidic. Despite having normal blood sugar levels before starting the medication and no family history of diabetes, his body had rapidly developed severe hyperglycemia (high blood sugar), metabolic acidosis, and ketones in his urine—the hallmarks of DKA.

What made this case particularly striking was that standard diabetes tests came back negative. His hemoglobin A1c—a measure of average blood sugar over three months—was normal at 5.7%. Autoantibody tests for Type 1 diabetes were negative, indicating no autoimmune attack on insulin-producing cells. His C-peptide level was elevated, showing his pancreas was still producing adequate amounts of its own insulin. Yet his body was in crisis.

Long-acting growth hormone (LAGH) formulations like lonapegsomatropin are prescribed to help children with growth hormone deficiency grow properly. One of the known side effects of growth hormone therapy is transient insulin resistance—a temporary state where the body doesn't respond as well to its own insulin, causing blood sugar to rise. This is usually mild and manageable, but it can be significant in certain patients.

In this boy's case, multiple risk factors may have combined to push a manageable side effect into a life-threatening condition. He had obesity, which itself causes insulin resistance. He was also taking glucocorticoids (hydrocortisone) as replacement therapy for his pituitary condition, and these hormones are also known to increase insulin resistance. The acute insulin resistance from the growth hormone may have overwhelmed his pancreas's ability to keep up, triggering DKA.

The boy's underlying condition—hypopituitarism following treatment of a brain tumor—meant his endocrine system was already under stress and carefully balanced on replacement hormones. Adding growth hormone to this delicate situation may have been the tipping point.

Once DKA was recognized, the boy received standard emergency treatment: insulin therapy and IV fluids to restore normal blood chemistry and pH. He recovered from the acute crisis. Importantly, when growth hormone therapy was discontinued, he returned to normal blood sugar levels and remained normoglycemic (with healthy blood sugar).

This case is rare—DKA triggered by growth hormone therapy alone in a patient without prior diabetes is uncommon. But it is a reminder that growth hormone is a powerful hormone that can have unexpected effects, especially in patients with multiple risk factors.

The authors recommend that doctors consider more frequent glucose monitoring when starting long-acting growth hormone in high-risk patients—particularly those with obesity, those taking glucocorticoids, or those with other metabolic risk factors. Catching blood sugar changes early may prevent progression to DKA and allow doctors to manage the side effect while still providing the growth benefit these children need.

Source: JCEM case reports. Evidence type: PubMed indexed literature. Type1Cure is an information and intelligence hub, not a medical advice service. This article summarizes published research and does not provide diagnosis, treatment, or personal medical guidance. Always talk to your own care team before changing anything about your Type 1 diabetes management.