Abstract

Von Recklinhausen diseaseof the bone or Osteitis fibrosa cystica as the name implies refers to the skeletal disorder characterised by osteoclastic bony resorption with peritrabecular fibrosis and formation of cyst like lesions in response to parathormone hypersecretion by the over- active parathyroid glands. This hyper-activity may be triggered by a parathyroid adenoma/ carcinoma, renal osteodystrophy or may be part of an inherited syndrome. The treatment consists of treating the primary cause which in most cases is resection of the parathyroid adenoma leaving the normal parathyroids intact.

Case Report

A 58-year-old gentleman presented to the Department of Orthopedics at Sri Ramachandra Medical Center, Chennai with a six month old history of multiple bony pain and swelling of the left jaw. He was previously evaluated and suspected to have metastases from an unknown primary with the possibility of a multicentric giant cell tumor and fibrous dysplasia following magnetic resonance imaging , cytology and histopathology. Computed tomography revealed expansile mass lesions involving the right ilium while other plain radiographs and bone scan showed similar lesions in the mandible and left tibia.

On biochemical evaluation he was found to have more than 10-fold rise in parathormone levels with hypercalcemia and elevated renal function. He underwent ultrasound neck followed by sestamibi scan of parathyroid to confirm the diagnosis of parathyroid adenoma.

He underwent removal of the left inferior parathyroid with needle aspiration of lesion on left side mandible on 2.9.11. Immediate post-operative period was uneventful and his endocrine status miraculously diverted to normal levels although renal function remained elevated. Specimen was sent for histopathology and report was in favor of parathyroid adenoma.

A month later, on 10.10.11 he underwent segmental resection of left side mandible and reconstruction with recon plate with curettage of the lesion in his right side due to risk of impending pathological fracture. Immediate post-operative period he developed respiratory distress secondary to mechanical compression by hematoma. The hematoma was drained and he underwent tracheostomy for airway maintenance.

His blood values before and after surgery are given in Table 1. A week following the second surgery he was transferred to ward and then readmitted in the intensivecare unit for dyspnoea and the possibility of multiple endocrine neoplasia. It was ruled out with 24 hour urine VMA 16.5 ( N< 15 mg/24 hours) and 24-hour urine metanephrines 30.0 (N<350 mg/24 hours).Presently patient is symptomatically better.

Discussion

Hyperparathyroidism is characterized by chronic hypersecretion on PTH by the parathyroids resulting in hypercalcemia. It occurs in 0.1% of adult patients, is more common in 20-50 years and more prevalent in females. 90% of the patients with hypercalcemia have either primary hyperparathyroidism or hypercalcemia of malignancy but PTH is suppressed in the latter. Excessive PTH secretion can cause diffuse bony resorption, hypercalcemia with hypercalciuria and hyperphosphaturia resulting in renal stones, patchy cystic bone lesions and pathological fracture. Most cases may be asymptomatic while some present with manifestations of hypercalcemia and renal and skeletal disorders aptly put as ‘painful bones, renal stones, abdominal groans and psychic moans’.On the skeletal aspect, bone radiographs show well circumscribed unilocular or multilocular radiolucent lesions known as “brown tumor” of hyperparathyroidism which is rare due to early detection these days. Brown tumors are called so since they are rich in hemorrhagic tissue with hemosiderin giving it a characteristic dark- reddish brown color.

Degeneration leads to patchy resorption with cystic lesions and replacement of bone with abundant vascular cellular fibrous tissue (‘osteitis firbosa cystica’). X-ray skull may show a ‘salt and pepper appearance’.Almost all who undergo parathyroidectomy experience increased bone density and repair of the skeleton within weeks. Additionally, patients with osteitis fibrosa cystica who have undergone parathyroidectomy begin to show regression of brown tumors within six months.

Following parathyroidectomy, hypocalcaemia is common. This results from a combination of suppressed parathyroid glands due to prolonged hypercalcaemia, as well as the need for calcium and phosphate in the mineralization of new bone.