Primary hyperparathyroidism. A rare cause of spinal cord compression

We report a case of a 62-year-old postmenopausal hypertensive lady who was treated for osteoporosis with calcium and Vitamin D. She presented with progressive lower limb weakness and paresthesia with sensory level at T4. Investigations revealed high parathyroid hormone 1152 ng/dl, calcium 10.9 mg/dl, and low phosphorus of 2.4 mg/dl after stopping calcium supplement. Chest x-ray showed an expansile mass lesion of the right 6th rib confirmed by chest CT. Thoracic MRI showed a mass lesion extending from the T3 vertebral body and compressing the spinal cord. There were multiple lytic lesions of the scalp, ribs, femur, and pelvis suggesting metastatic lesions. A neck ultrasound and SESTA MIBI parathyroid scan confirmed a right lower parathyroid adenoma. Excision biopsy of the rib lesion confirmed a vascular lesion with features of brown tumor BT. Decompression surgery of the thoracic spine was performed, and the histopathology confirmed BT. Two weeks later the patient underwent right parathyroidectomy that proved to be a parathyroid adenoma. She showed a remarkable improvement in her clinical condition and there were some regression of the bony lesions observed 12 months post parathyroidectomy. This case should alert physicians to the association of multiple brown tumors in PHPT and that the presentation may be an aggressive one mimicking metastasis, patients with osteoporosis warrant at least calcium profile to rule out a secondary cause.