Acromegaly: Understanding the Causes, Symptoms, and Treatment Options for Excess Growth Hormone
Acromegaly is a rare hormonal disorder that occurs when the pituitary gland produces an excessive amount of growth hormone (GH), typically due to a benign tumor known as a pituitary adenoma. This condition primarily affects adults, although it can also develop in adolescents before their growth plates have closed. The overproduction of growth hormone leads to abnormal growth of body tissues, especially in the extremities and internal organs, resulting in distinct physical changes and systemic complications.
How Acromegaly Affects the Body
The hallmark of acromegaly is the progressive enlargement of bones and soft tissues, particularly in the hands, feet, face, and internal organs. In adults, this manifests as swollen fingertips and toes, thickened skin, and noticeable facial alterations such as a protruding jaw (prognathism), enlarged nose, widened space between teeth, and prominent cheekbones. The voice may deepen due to vocal cord thickening, and patients often develop a barrel-shaped chest and kyphosis (curvature of the spine).
Symptoms in Adolescents vs. Adults
In younger individuals who are still growing, excess growth hormone does not lead to acromegaly per se but causes a related condition called gigantism. These adolescents experience rapid and extreme height increases—sometimes exceeding 8 feet (2.4 meters)—along with broad facial features, large hands and feet, and joint pain. Unlike adults, their long bones continue to grow due to open epiphyseal plates, leading to disproportionate stature.
Adults with acromegaly do not grow taller, but they suffer from gradual and often subtle physical changes that may go unnoticed for years. Other common symptoms include joint stiffness, fatigue, excessive sweating, sleep apnea, vision problems, and carpal tunnel syndrome. Over time, metabolic disturbances such as insulin resistance and hypertension may develop, increasing the risk of cardiovascular disease and diabetes.
Long-Term Complications and Disease Progression
If left untreated, acromegaly can lead to severe health consequences. Patients may experience premature aging, muscle weakness, chronic back pain from spinal deformities, and hair loss. Cognitive and emotional symptoms such as depression, low energy levels, and difficulty concentrating are also frequently reported. The persistent overactivity of growth hormone can also increase the risk of developing colon polyps and certain cancers.
Diagnosis and Monitoring
Diagnosing acromegaly involves measuring blood levels of insulin-like growth factor 1 (IGF-1), which is elevated in response to high GH levels. An oral glucose tolerance test (OGTT) is used to confirm the diagnosis, as growth hormone levels should normally suppress after glucose intake—but fail to do so in acromegaly. Imaging studies, particularly MRI of the brain, help locate and assess the size of the pituitary tumor.
Treatment Approaches for Acromegaly
The primary goal of treatment is to normalize growth hormone and IGF-1 levels, reduce tumor size, relieve pressure on surrounding brain structures, and improve quality of life. There are several effective strategies available:
Surgical Intervention
Transsphenoidal surgery, which involves removing the pituitary tumor through the nose and sinuses, is often the first-line treatment. When performed by experienced neurosurgeons, this minimally invasive procedure can lead to rapid hormone normalization, especially for smaller tumors. Success rates vary depending on tumor size and invasion into nearby tissues.
Radiation Therapy
For cases where surgery isn't fully effective or isn't possible, radiation therapy—including modern techniques like stereotactic radiosurgery or traditional methods using cobalt-60—can be used to shrink the tumor over time. While effective, radiation typically results in a slower decline in hormone levels and may take several years to achieve full benefit. It may also lead to long-term pituitary insufficiency, requiring lifelong hormone replacement.
Medical Management
Pharmacological treatments are often used alongside or instead of surgery and radiation. These include somatostatin analogs (such as octreotide and lanreotide), dopamine agonists (like cabergoline), and growth hormone receptor antagonists (such as pegvisomant). These medications help control hormone secretion, reduce tumor size, and alleviate symptoms.
Early detection and comprehensive management are crucial in preventing irreversible damage and improving long-term outcomes for individuals with acromegaly. With advances in diagnostics and treatment, most patients can achieve normal hormone levels and lead healthy, active lives.