Reduced Bone Density in Patients with Autosomal Dominant Hyper-IgE Syndrome

Background and Purpose Autosomal dominant hyper-IgE syndrome (AD-HIES) is a rare primary immunodeficiency disorder. It has been recognized as a multisystem disorder and is characterized by both immunologic and non-immunologic manifestations. Possible bone involvement in autosomal dominant HIES include fractures, scoliosis, cystic bone changes, and osteopenia. We sought to evaluate the changes in bone density in adolescents and young adults with AD-HIES, mostly with proven STAT3 mutation, followed in our institute. Methods We studied eight patients with AD-HIES who attended our immunology clinic. All patients underwent at least one bone mass dual-energy x-ray absorptiometry assessment (dual-energy x-ray absorptiometry scan). These findings were evaluated. Results The age of the patients at the time of their first bone density scan ranged between 10 and 24 years (mean 16.1 +/- 4.0 years); the duration of follow-up was 4-11 years (mean 5.8 +/- 3.5 years). Four patients had a history of fractures. Mean Z score in these patients was -1.8 +/- 0.7. For three patients, Z score was below -1. The other four patients had no history of fractures. Mean Z score in these patients was -0.9 +/- 0.5. Only one patient in this group had a Z score below -1. Bone density was below average in all patients; mean spinal Z score was -1.6 +/- 0.4. Four patients were followed through the second decade, and all showed progressive deterioration in bone density. Three were treated with alendronate sodium, with improvement in the bone scan results. Conclusions Bone density decreases considerably over time in adolescents and young adults suffering from AD-HIES. Treatment with alendronate sodium may be effective in alleviating osteopenia.