A 46 year old female presented to orthopaedics with a painful swelling at the base of the middle finger, which was gradually increasing in size. Ultrasound and x-ray showed a highly vascular irregular mass with bony involvement of the third metacarpal. Initial suspicions were of an enchondroma. Following an MRI scan, the orthopaedic team proceeded to biopsy the lesion. The histology suggested a giant cell tumour. Curretage of the lesion, with bone grafting was performed and further histology taken for a further opinion. This again suggested a giant cell tumour of soft tissue. Whilst awaiting further investigations, the patient described increasing pain in her left hip. Blood investigations revealed an adjusted calcium concentration of 3.29 mmol/l (reference range 2.202.60 mmol/l). Her parathyroid hormone level was elevated at 71.1 pmol/l (reference range 0.96.5 pmol/l). A suspected diagnosis of primary hyperparathyroidism with a Brown tumour therefore followed. CT delineated multiple expanded lucent bone lesions consistent with Brown tumours. Also an irregular soft tissue mass of approximately 2 cm in diameter was identified adjacent to the left inferior pole of the thyroid. A SPECT scan described an intense focus of abnormal activity at this site. DEXA confirmed the presence of significant osteoporosis. She underwent planned parathyroidectomy with pre-loading of vitamin D. There was no evidence of post-operative hypocalcaemia and she has gone on to make a good recovery. Her subsequent imaging has shown significant improvements in bone health. This case represents a now relatively rare presentation of primary hyperparathyroidism. The textbook symptomatic presentation with renal stones and bone pain is far less frequent than the more common finding of incidental hypercalcaemia- with only ~1% presenting with skeletal disease. However, atypical presentions can still occur in endocrinology and other specialities, and considering the diagnosis is key.
19 Nov 2018 - 21 Nov 2018