Endocrine Abstracts

A female patient presented at the age of 30 years with an incidental radiological finding of hyperostosis after a traumatic knee ligament injury. Her large facial contours with wide hands and fingers reminded acromegalic features but without typical soft tissue changes. Hormone evaluation discovered an elevated IGF-1, growth hormone (GH) was non-suppressed on glucose load, but pituitary MRI was normal. The imaging revealed remarkable cortical thickening of long bones with prominent homogenous cranial hyperostosis, large and thick facial bones, sclerotic vertebral bodies and hypertrophic metatarsal and phalangeal bones. The bone mass density was extremely increased with Z-scores values between +10 and +13. An inborn flexion contracture of the left index, clubbing fingers and dysplastic nails were observed. The intracranial space was reduced, but without significant brain compression. Beside some occasional nonspecific headaches, she has been asymptomatic with no cranial nerves damage. After being lost for follow up, her condition was re-evaluated 8 years later. Her headaches did not deteriorate. She complained of progressive exophthalmos, torus palatinus and she had worsening nasal obstruction with pronounced sleep apnea due to the extreme narrowing of the nasal cavity. The thickness of her occipital bone reached 35 mm but no evident change in intracranial compression occurred. A surgical widening of the nasal airway was performed. The modelling of orbital rims and the floor of the orbit to reduce exophthalmos was done. The reduction of the mandible and the maxilla resulted in considerable clinical and facial contours improvement and the sleep apnea was significantly reduced. The predominant craniotubular hyperostosis and digit deformities in this patient are similar to skeletal alterations found in sclerosteosis. The DNA was sent for investigation, but no known high bone mass causative mutations have been confirmed yet. We are not aware of any other family member with such a phenotype. The patient had again a hormonal profile mimicking acromegaly without typical clinical sequelae of GH over-secretion. Pituitary, thorax and abdomen imaging did not reveal any process suspicious for neuroendocrine tumour. Due to technical reasons, we could not send her blood for GH-releasing hormone determination. The disorder of the GH axis is still unresolved, but clinical data make us believe that this is not a consequence of some autonomous secretion. Hyperostotic bone diseases are very heterogeneous, usually related with mutations in the complex Wnt signaling pathway and this case might suggest an unknown interaction with the GH secretion.