Adult growth hormone deficiency treatment with a combination of growth hormone and insulin-like growth factor-1 resulting in elevated sustainable insulin-like growth factor-1 and insulin-like growth factor binding protein 3 plasma levels: a case report

INTRODUCTION Adult Growth hormone Deficiency is a well known phenomenon effecting both males and females. Adult Growth Hormone Deficiency is marked by a number of neuropsychiatric, cognitive performance, cardiac, metabolic, muscular, and bone symptoms and clinical features. There is no known standardized acceptable therapeutic modality to treat this condition. A recent meta-analysis found that after 16 years of Growth Hormone replacement therapy a large proportion of the patients still had Growth Hormone associated symptoms especially related to executive functioning. A major goal is to increase plasma levels of both insulin-like growth factor (insulin-like growth factor-1) and insulin-like growth factor binding protein 3. CASE PRESENTATION We report a case of a 45-year-old caucasian woman with early ovarian failure for 2 years and amenorrhea since the age of 43, who presented with Adult Growth Hormone Deficiency and an IGF-1 of 126 ng/mL. Since her insulin-like growth factor-1 was lowest at 81 ng/mL, she was started on insulin-like growth factor-1 Increlex at 0.2 mg at bedtime, which immediately raised her insulin-like growth factor-1 levels to 130 ng/mL within 1 month, and 193 ng/mL, 249 ng/mL, and 357 ng/mL, after 3, 4, and 5 months, respectively, thereafter. Her insulin-like growth factor binding protein 3 continued to decrease. It was at this point when we added back the Growth Hormone and increased her Increlex dosage to 1.3 - 1.5 mg that her insulin-like growth factor binding protein 3 began to increase. CONCLUSION It appears that in some patients with Adult Growth Hormone Deficiency, insulin-like growth factor-1 elevation is resistant to direct Growth Hormone treatment. Furthermore, the binding protein may not rise with insulin-like growth factor-1. However, a combination of Growth Hormone and insulin-like growth factor-1 treatment may be a solution.