An 81-year-old man presented with severe proximal muscle pain, reduced mobility, and a history of frequent falls as well as knee osteoarthritis, hypertension, and a vertebral wedge collapse nearly 2 decades earlier. Clinical examination revealed ankle swelling and left knee synovitis, as well as bilateral quadriceps muscle wasting and grade 4 or 5 muscle power.
Scintigraphy showed the Lone Ranger sign, with increased uptake in the skull and around the eyes and reduced soft tissue activity. Laboratory evaluations identified and elevated calcium level, at 4.02 mmol/L, and an elevated alkaline phosphate level, at 782 U/L, which suggested severe bone disease.
Diagnosis
The diagnosis, based on scintigraphy and other radiographic investigations, was long-standing parathyroid bone disease complicating primary hyperparathyroidism (Ann. Rheum. Dis. 2006;65:1244).
The scintigraphic findings were characterized as a superscan, in which there is diffuse increased skeletal uptake relating to increased bone turnover and which can appear to be a negative or normal scan. This appearance is more common in metastatic cancer and is quite unusual in hyperparathyroid bone disease, according to Dr. D. John Pradeep of Norfolk and Norwich University Hospital, Norwich, England.
Hyperparathyroidism itself today is usually detected quite early, and a presentation such as this, with extensive bone disease, is quite rare, Dr. Pradeep said in an interview. Aside from the scintigraphic findings, hyperparathyroidism also is characterized by x-ray findings of brown tumors, which are small lytic lesions of the hip.
Further diagnostic evaluation of this patient using ultrasound and Tc-99m sestamibi scanning identified a mass by the left upper pole of the thyroid. The tumor was removed by minimally invasive parathyroidectomy, and histologically was found to be a benign adenoma.