Endocrine Abstracts

Context: Acromegaly is associated with many complications, which affects multiple systems, such as cardiovascular, respiratory, metabolic, muscles and bones. Osteoporosis and osteoporosis fracture are commonly neglected comorbidity of this rare disease. Usual manifestation of this skeletal complication is skeletal fragility and vertebral fractures, but prior research confirms, that other location fractures can be found as well.

Case illustration: We report the case of a 54-year-old woman, admitted with elevated blood pressure, hot flushes, episodes of intensive headaches, metacarpophalangeal joints pain, carpal tunnel syndrome, morning stiffness of joints. In 2018, laboratory test (increased insulin-like growth factor (IGF-1) 62,0 nmol/l (16,0 – 42,8)) in addition to clinical findings suspected acromegaly. MRI of the head was performed and pituitary macroadenoma was identified, size 34x46x35 mm, invading the left cavernous sinus. Histologically, macroadenoma was non-granulated with expression of Pit-1 transcription factor. Subtotal transsphenoidal adenectomy was performed in 2018. After surgery, somatostatin receptor ligand (SRL) Lanreotide 90 mg per week was prescribed, but IGF-1 concentration remained above normal range 42,1 nmol/l. Treatment was changed to Pasireotide LAR 40 mg every 28 days, but IGF-1 persisted uncontrolled. Patient started Cabergoline incrementally. Unfortunately, control head MRI demonstrated increased size of adenoma. In May 2020, according to the decision of multidisciplinary team, stereotactic radiotherapy surgery was performed. After surgery, Cabergoline 2 mg 2 times per week was continued. Six months after surgery IGF-1 level normalized – 22,7 nmol/l, growth hormone (GH) level remained increased 8,4 mU/l (0 – 6,3 mU/l). Eight months after radiosurgery patient admitted to the hospital with a fracture of the acetabulum, without dislocation, no surgery was required. The fracture occurred after a fall at home. DXA was performed, femoral neck T- score was -2,5. Osteoporosis was diagnosed. The patient was prescribed with Denosumab 60 mg every 6 months. No other bone fracture was registered since.

Discussion : Studies confirm that exceeded secretion of IGF-1 and GH enhances deterioration of bone and can lead to osteoporosis or even bone fractures. Unfortunately, the management of bone impairment in patients with acromegaly still need more attention, since the acknowledgement of this complication sometimes left forgotten.

References: Melmed S. Pituitary-tumor endocrinopathies. N Engl J Med. 2020;382(10):937-950. Management of endocrine disease: Bone Disorders associated with acromegaly: Mechanisms and treatment. European Journal of Endocrinology. 2019;181(2).