New bone formation in acromegaly: pathogenetic implications for diffuse idiopathic skeletal hyperostosis

Area of Science:

• Endocrinology
• Rheumatology
• Radiology

Background:

• Acromegaly is a hormonal disorder characterized by excessive growth hormone production.
• Diffuse Idiopathic Skeletal Hyperostosis (DISH) involves abnormal bone growth, particularly in the spine.
• Hyperostosis Frontalis Interna (HFI) is a thickening of the inner table of the frontal bone.

Purpose of the Study:

• To investigate the prevalence and characteristics of hyperostotic changes in patients with acromegaly.
• To compare skeletal findings in acromegaly with those of Diffuse Idiopathic Skeletal Hyperostosis (DISH).
• To explore potential common underlying factors contributing to bone changes in both conditions.

Main Methods:

• Radiographic examination of the spine, heel entheses, and skull in 30 acromegalic patients.
• Assessment for new bone formation and hyperostotic changes.
• Correlation of skeletal findings with the duration of acromegaly.

Main Results:

• 47% of acromegalic patients met criteria for Diffuse Idiopathic Skeletal Hyperostosis (DISH).
• 67% exhibited marked heel enthesopathic changes.
• 87% presented with Hyperostosis Frontalis Interna (HFI), indistinguishable from DISH findings.
• The extent and severity of hyperostotic changes increased with the duration of acromegaly.

Conclusions:

• Acromegaly is associated with a high prevalence of hyperostotic bone changes, including features of DISH and HFI.
• These skeletal manifestations in acromegaly appear similar to those seen in DISH.
• A shared metabolic factor, such as hyperinsulinaemia, is proposed as a potential cause for these bone changes in both acromegaly and DISH.