Recovery pattern of patients with osteitis fibrosa cystica in primary hyperparathyroidism after successful parathyroidectomy

Brown Tumors of the Jaws: A Retrospective Study

Objectives

(1) Describe the clinical spectrum, imaging features, management, and outcome of brown tumors (BT) of the jaws. (2) Determine via a literature review the facts and controversies around the characteristics and management of this lesion.

Materials and methods

Our study was approved by the institutional committee of Sahloul University Hospital in accordance with the ethical standards of the Declaration of Helsinki. Sixteen patients with BT in the context of a primary, secondary, and tertiary hyperparathyroidism were treated and followed up during their recovery.

Results

This study reports 16 patients with a mean age of 48 years old. Brown tumor lesions were associated with primary hyperparathyroidism in 6 cases (38%), secondary hyperparathyroidism to chronic kidney failure in 5 cases (31%), and tertiary hyperparathyroidism in the context of a long lasting CRI in 5 cases. Their location was maxillary in 7 cases, mandibular in 5 cases, and bimaxillary in 4 cases. The treatment consisted of parathyroidectomy in 13 patients, maxillary resection in 3 cases, and vitamin D treatment in 2 cases. Favorable outcomes, characterized by tumor regression, were reported in 9 cases, whereas unfavorable evolution was observed among 7 patients.

Conclusion

Parathyroidectomy is the gold standard treatment for primary hyperparathyroidism. It resulted in a total regression in all our cases. Regarding secondary hyperparathyroidism, blood screening and chronic renal insufficiency follow-up are critically valuable to detect this condition at an early stage, hence increasing the success rate of brown tumor regression. Our secondary and tertiary hyperparathyroidism results were miscellaneous; although it is important to emphasize the importance of the chronic renal insufficiency management to ensure a success.

Clinical relevance

Brown tumors should be included in the differential diagnosis of giant cell lesions. Parathyroidectomy is usually sufficient to induce the total regression of the lesion in primary hyperparathyroidism cases. A more delicate approach is needed regarding secondary hyperparathyroidism. Meticulous control of chronic renal insufficiency is mandatory in addition to parathyroidectomy.

Misdiagnosis of brown tumour caused by primary hyperparathyroidism: a case report with literature review

BACKGROUND

Brown tumour is a rare tumour-like lesion of the bone, which is considered as an end-stage lesion of abnormal bone metabolism caused by persistently high parathyroid hormone (PTH) levels. Brown tumour can be found in any part of the skeleton; in some cases, it can occur in multiple bones and can be easily misdiagnosed as a metastatic tumour.

CASE PRESENTATION

We report the case of a 44-year-old man who presented to the Department of Oncology in our hospital with a 2-month history of local pain in his left shoulder joint. The initial diagnosis was an aneurysmal bone cyst by biopsy, for which the patient underwent tumour resection surgery. The diagnosis of a malignant tumour was made again following postoperative pathological examination. The pathological sections and all clinical data were sent to the Department of Pathology of the First Affiliated Hospital of Sun Yat-sen University; the diagnosis made there was brown tumour. His blood PTH level was 577 pg/ml (15-65 pg/ml). Colour Doppler ultrasonography of the parathyroid gland suggested a parathyroid adenoma. For further treatment, the left parathyroid adenoma was removed by axillary endoscopic resection. Postoperatively, a pathologic examination was performed, and the diagnosis of a parathyroid adenoma was confirmed. One year after the surgery, the left humerus was completely healed, and the left shoulder joint had a good range of movement.

CONCLUSIONS

In summary, histopathological diagnosis is not sufficient for the diagnosis of brown tumours. A comprehensive analysis combining clinical symptoms with findings of imaging and laboratory tests is also required. Generally, the treatment of brown tumour includes only partial or complete resection of the parathyroid glands. However, when the tumour is large, especially when it involves the joint, surgery is indispensable.

Hungry bone syndrome following parathyroidectomy for primary hyperparathyroidism in a developed country in the Asia Pacific. A cohort study

Objectives

We sought to assess the incidence of hungry bone syndrome (HBS) following parathyroidectomy (PTX) for primary hyperparathyroidism (PHPT) in a cohort of multi-ethnic patients from a developed country in the Asia Pacific.

Methods

One hundred and sixty-four patients who underwent PTX for PHPT between 2012 and 2019 at the 2 largest public hospitals in Singapore were identified. HBS was defined as serum albumin-adjusted calcium ≤ 2.1 mmol/L with normal or raised serum intact parathyroid hormone (iPTH) levels, manifesting on or after the 3rd day, or persisting for more than 3 days post-operatively.

Results

Chinese constituted 73.8%, Malays 12.2%, Indians 9.8%, and other races 4.3%. HBS developed in 4 patients (2.4%) (95% CI, 0.8%–6.5%). HBS patients had significantly longer in-hospital stays; 20 days [IQR:15–22] vs 2 days [IQR:1–3]; P < 0.001in those who did not develop HBS. There was no difference in the incidence of HBS stratifying for age, sex, vitamin D status, or use of preoperative anti-resorptive medication use. For every 10 unit increase in iPTH and alkaline phosphatase (ALP) levels, the risk of HBS increased by 14% and 11%; RR (95% CI), 1.14 (1.05–1.21) and 1.11 (1.03–1.18), respectively.

Conclusions

The low incidence of HBS in multi-ethnic patients undergoing PTX by multiple surgeons for PHPT at the 2 largest public hospitals that see the most such patients in Singapore, a developed country, is consistent with the asymptomatic/milder form of presentation of PHPT in the developed world.

Primary Hyperparathyroidism in the Common Orthopaedic Practice

An extensive review of the publications on primary hyperparathyroidism (pHPT) is presented in this report. It has strongly been emphasized in the literature that patients with pHPT may present either with the classical symptomatology or with asymptomatic disease, emerged due to biochemical screening. The clinical and epidemiological presentation of pHPT in western countries has changed profoundly during the past few decades, and bone disease is nowadays a distinct rarity. The introduction of serum calcium screening for osteoporosis and the technological advances in the laboratory assessment of parathyroid hormone have played important roles in early diagnosis. Subsequently, the disease is increasingly being detected as asymptomatic hypercalcaemia without guiding signs or symptoms. A third type of disease, the normocalcaemic variant, has been recently described in the literature. However, the potential diagnosis of pHPT should always be on the orthopaedics’ list of differential diagnoses in female or elderly patients with vertebral fractures and nephrolithiasis, either symptomatic or asymptomatic, as well as when solitary or multiple osteolytic lesions are encountered on the radiographs.

Additionally, a middle aged woman with parathyroid adenoma and subsequent brown tumors detected on the pelvic radiographs is reported. Her initial laboratory findings indicated a minimal increase of the serum calcium, a mild increase of the erythrocyte sedimentation rate, and a significant increase in total serum alkaline phosphatase. Finally, the detection of elevated parathyroid hormone levels indicated the diagnosis of pHPT and necessitated imaging studies of the parathyroid glands, which indicated a parathyroid adenoma. Following successful excision of the parathyroid adenoma, the patient suffered from the hungry bone syndrome. After a follow-up of 20 years, the patient had normal calcium, vitamin D, and parathyroid hormone serum levels, while a pelvic radiograph indicated no significant changes in the appearance of the brown tumors.

Primary Hyperparathyroidism in the Common Orthopaedic Practice

An extensive review of the publications on primary hyperparathyroidism (pHPT) is presented in this report. It has strongly been emphasized in the literature that patients with pHPT may present either with the classical symptomatology or with asymptomatic disease, emerged due to biochemical screening. The clinical and epidemiological presentation of pHPT in western countries has changed profoundly during the past few decades, and bone disease is nowadays a distinct rarity. The introduction of serum calcium screening for osteoporosis and the technological advances in the laboratory assessment of parathyroid hormone have played important roles in early diagnosis. Subsequently, the disease is increasingly being detected as asymptomatic hypercalcaemia without guiding signs or symptoms. A third type of disease, the normocalcaemic variant, has been recently described in the literature. However, the potential diagnosis of pHPT should always be on the orthopaedics’ list of differential diagnoses in female or elderly patients with vertebral fractures and nephrolithiasis, either symptomatic or asymptomatic, as well as when solitary or multiple osteolytic lesions are encountered on the radiographs.

Additionally, a middle aged woman with parathyroid adenoma and subsequent brown tumors detected on the pelvic radiographs is reported. Her initial laboratory findings indicated a minimal increase of the serum calcium, a mild increase of the erythrocyte sedimentation rate, and a significant increase in total serum alkaline phosphatase. Finally, the detection of elevated parathyroid hormone levels indicated the diagnosis of pHPT and necessitated imaging studies of the parathyroid glands, which indicated a parathyroid adenoma. Following successful excision of the parathyroid adenoma, the patient suffered from the hungry bone syndrome. After a follow-up of 20 years, the patient had normal calcium, vitamin D, and parathyroid hormone serum levels, while a pelvic radiograph indicated no significant changes in the appearance of the brown tumors.

Brown tumour mimicking skeletal metastasis

Brown tumours of bone are highly vascular osteolytic lesions that depict a reparative cellular process instead of a neoplastic process in hyperparathyroidism (HPT) patients. These tumours have the potential to be aggressive and destructive. We report a case of a 30-year-old woman who presented with left thigh and lower back pain. The radiological evaluation showed multiple bony lesions in the pelvis and the spine, which mimicked multiple metastatic tumours. However, on biochemistry evaluation, serum calcium, alkaline phosphatase, and parathyroid hormone were all high, while serum phosphate was low, indicating primary HPT (PHPT), which was confirmed by parathyroid scintigraphy showing left parathyroid adenoma. Hence, the bony lesions were diagnosed as brown tumours secondary to PHPT. The patient underwent parathyroidectomy and developed severe hungry bone syndrome requiring parenteral calcium infusion along with oral calcium and active vitamin D supplementation. The clinical symptoms of bone pain improved after surgery.

Osteitis Fibrosa Cystica and pathological fractures-the classic but neglected skeletal manifestation of primary hyperparathyroidism: a case report

BACKGROUND

Osteitis fibrosa cystica is the classic manifestation of primary hyperparathyroidism (PHPT), occurs after prolonged exposure of bone to high serum parathyroid hormone (PTH) level. It has become increasingly rare due to early detection of PHPT.

CASE PRESENTATION

A 37-year-old woman was referred to our institution for fixation of multiple fractures of upper and lower extremities that had been reoccurring in the past 5 years. Her medical history showed right-shoulder, left-elbow, and right-femur fractures after a fall 5 years previously. One month ago, she sustained fractures of the right distal humerus, left tibia, and left femur without history of trauma. Upon arrival to our hospital, a thorough review of her plain radiographs demonstrated brown tumors at multiple sites, along with a salt-and-pepper appearance of the skull and a rugger-jersey spine, compatible with osteitis fibrosa cystica. Patient was diagnosed with PHPT, confirmed by high-corrected serum calcium (13.6 [8.6-10.0] mg/dl), low serum phosphate (2.2 [2.5-4.5] mg/dL), high serum alkaline phosphatase (1482 [35-105] U/L), and significantly elevated parathyroid hormone (PTH 3850 [15-65] pg/mL). A histologically confirmed, 2.5-cm parathyroid adenoma was removed by parathyroidectomy. Ten days later, closed reduction and internal fixation of the left proximal femoral shaft was performed. Pain and ambulation were significantly improved 6 months postoperatively. At the 1.5-year follow-up, fracture unions and complete mineralization of brown tumors were noted; the patient could ambulate with neither pain nor an assistive device.

CONCLUSIONS

PHPT has become more asymptomatic in countries where routine calcium screening is performed. Nevertheless, the classic skeletal involvement, osteitis fibrosa cystica, should not be overlooked, particularly in young patients who present with a low-energy fracture.

Intensive calcium monitoring improves outcomes on hungry bone syndrome in hyperparathyroidism

Objectives. Hungry bone syndrome (HBS) is a severe and underdiagnosed complication of parathyroidectomy in the treatment of primary hyperparathyroidism (PHP) and secondary hyper-parathyroidism to chronic kidney disease (SHP-CKD).Methods. A longitudinal study was conducted to compare the postoperative outcomes of patients who developed HBS in two different time frames: before and after implementing a protocol with an intensive electrolytic monitoring and an algorithm regarding electrolytic supplementation.Results. Overall, 77 parathyroidectomies were included. In PHP, a protocol implementation led to an increased admission of patients in the Intermediate Care Unit for intensive electrolytic monitoring (p<0.001) and an increased rate of oral calcium replacement during hospital stay (p=0.013) compared to pre-protocol era. In SHP-CKD, duration of intravenous calcium replacement was reduced (p=0.010). The prevalence of HBS (9.8% in PHP and 58.3% in SHP-CKD) was similar between the two periods, although its diagnosis had an increased trend in PHP since the protocol implementation. None of the diagnosis of HBS was established due to hypocalcemic symptoms in the post-protocol era (contrary to pre-protocol period, p=0.021). Both hypocalcemia length and duration of surgical ward hospitalization were reduced (p=0.047 and p=0.042, respectively).Conclusions. An improved assessment of hyperparathyroidism and a decrease in HBS severity were noted in the post-protocol era. We strongly recommend the implementation of a standardized protocol with an intensive phosphocalcium monitoring in the high-risk patients who undergo parathyroidectomy due to hyperparathyroidism as it improves the health care and management of HBS.

Severe hypercalcemia and a pelvic brown tumor in an adolescent with primary hyperparathyroidism: a case report

BACKGROUND

Primary hyperparathyroidism may present in a myriad of manners, varying from an incidental asymptomatic biochemical finding to gastrointestinal, psychiatric, renal, and bone manifestations. While hyperparathyroidism remains a rare diagnosis in the pediatric population, the initial approach to diagnosis and management of hypercalcemia in children is imperative for the general pediatrician. Herein, we describe an adolescent who presented with a lytic bone lesion and severe, symptomatic hypercalcemia due to primary hyperparathyroidism.

CASE PRESENTATION

A 14-year-old male presented with vomiting, constipation, abdominal pain, and lethargy. He had an elevated total corrected calcium of 4.3 mmol/L. He was found to have a large pelvic lytic tumor consistent with a brown tumor due to primary hyperparathyroidism. He received pharmacologic therapy for stabilization of his hypercalcemia, including intravenous saline, intravenous bisphosphonates, and calcitonin. He subsequently received definitive therapy via parathyroidectomy and his post-operative course was complicated by hungry bone syndrome. Long-term follow-up has found full resolution of the lytic lesion and restored calcium homeostasis.

CONCLUSIONS

We present this case to highlight the possible presentations of hypercalcemia and hyperparathyroidism that are essential for a general pediatrician to recognize to ensure prompt diagnosis and management. Evaluation for hypercalcemia should be considered in patients with suggestive symptoms and physical exam findings. To our knowledge, this patient represents the first reported pediatric case of a pelvic brown tumor in an adolescent. While the multi-systemic complications of hyperparathyroidism may be quite severe, swift and appropriate management may mitigate these clinical outcomes.

Changes to bone mineral density, the trabecular bone score and hip structural analysis following parathyroidectomy: a case report

BACKGROUND

Reduction in bone mineral density (BMD) measured by dual-energy X-ray absorptiometry (DXA) occurs in secondary hyperparathyroidism associated with chronic kidney disease. BMD generally increases following parathyroidectomy, however longitudinal changes to other DXA-derived parameters, the trabecular bone score (TBS) and hip structural analysis (HSA), have not been described. Postoperative calcium requirements and positive calcium balance raise concerns for an increased risk of vascular calcification. This case illustrates the dramatic increase in BMD that can follow parathyroidectomy in a patient on dialysis, and for the first time demonstrates improvements to HSA parameters and to the TBS.

CASE PRESENTATION

A 30-year old woman on haemodialysis underwent subtotal parathyroidectomy for secondary hyperparathyroidism. She developed a post-operative 'hungry bone syndrome' requiring substantial calcium and calcitriol supplementation. Six months post-parathyroidectomy, BMD increased by 42% at the lumbar spine, 30% at the femoral neck and 25% at the total proximal femur, with increases sustained over the following 18 months. The TBS increased by 8%. HSA showed a 63% increase in femoral neck cortical thickness and 38% reduction in the buckling ratio, consistent with increased femoral neck stability. The abdominal aortic vascular calcification score (0-24) increased from zero 8-years pre-parathyroidectomy to 2/24 at 18-months post-parathyroidectomy.

CONCLUSION

BMD losses incurred by secondary hyperparathyroidism recover rapidly after parathyroidectomy, particularly at sites of trabecular bone. Bone architectural parameters, measured as the TBS and by HSA, also improve. Greater BMD gains may be associated with higher post-operative calcium requirements. While bone is the major reservoir for post-parathyroidectomy calcium supplementation, positive calcium balance may contribute to vascular calcification risk.

A brown tumor secondary to hyperparathyroidism in the maxilla, skull, scapula, and femora

Primary hyperparathyroidism presenting with diffuse skeletal involvement, such as discrete osteoclastic bone lesions, is rare. We describe a 35-year-old woman who presented with a left mandibular mass that rapidly enlarged over 3 weeks. Radiological, histological, and biochemical investigations led to the diagnosis of brown tumor secondary to primary hyperparathyroidism. A neck ultrasound revealed a 1.5 × 2.3 × 4.6 cm mass at the lower pole of the left thyroid lobe, suggestive of a parathyroid adenoma. Bone scan showed additional abnormal foci of increased uptake in the maxilla, both femora, skull, and scapula. Brown tumors are treated primarily by correcting the underlying endocrine disorder, and a parathyroidectomy was performed.

Parathyroid adenoma combined with a rib tumor as the primary disease: A case report

BACKGROUND

Parathyroid adenoma is a benign parathyroid tumor, with serum parathyroid hormone and calcium ion concentrations as the typical basis for diagnosis. Its clinical manifestations are complex and changeable; thus it is easily missed or misdiagnosed. Approximately 85% of patients with parathyroid adenoma develop primary hyperparathyroidism, and abnormalities in bones, kidneys and other organs can occur. Brown tumors are rare.

CASE SUMMARY

We report a rare case of fibrocystic osteitis associated with a parathyroid adenoma, which was discovered by chance due to a rib tumor. Abnormally elevated serum parathyroid hormone and calcium ion were found before surgery. We suspected primary hyperparathyroidism, and color Doppler ultrasound suggested the presence of a thyroid mass. With informed consent by the patient and her family, we first removed the rib tumor, and one week later, resection of the parathyroid adenoma and thyroid mass was performed on both sides, and the patient recovered well after surgery.

CONCLUSION

In the case of parathyroid adenoma combined with brown tumor, the bone cyst will gradually decrease in size with time without treatment. If not, surgery should be performed as soon as possible.

A Hungry Bone Syndrome Predicted by 18F-Fluorocholine PET/CT

Predicting hungry bone syndrome (HBS) after surgical cure of primary hyperparathyroidism (PHPT) can be challenging. A 57-year-old man diagnosed with PHPT was assessed preoperatively by F-fluorocholine PET/CT. An intense and diffuse tracer uptake of the axial and peripheral skeleton was visualized, in addition to a pathologic uptake suggestive of hyperfunctioning parathyroid gland. After the removal of a parathyroid adenoma, a severe and prolonged HBS requiring high doses of calcium and active metabolites of vitamin D was observed. This observation suggests that intense and diffuse bone uptake on F-fluorocholine PET/CT could be a predictive factor for HBS in patients with PHPT.

Osteolytic lesions (brown tumors) of primary hyperparathyroidism misdiagnosed as multifocal giant cell tumor of the distal ulna and radius: a case report

Background

Brown tumors represent a rare clinical manifestation reported in approximately 3% of patients with primary hyperparathyroidism and correspond to radiologically osteolytic lesions with well-defined borders in different parts of the skeleton.

Case presentation

We report the case of a 53-year-old white man who presented to our hospital with osteolytic lesions of his distal ulna and radius, causing pain and swelling of 2-month duration. A subsequent biopsy revealed histological features consistent with giant cell tumor and a complete resection of his distal ulna was followed, along with curettage and cementoplasty of the distal radial metaphysis. Two weeks later, he was re-admitted with diffuse musculoskeletal soreness, anorexia, constipation, nausea, and localized abdominal pain and multiple osteolytic lesions on plain radiographs. A histopathological examination of the ulna and radius specimens showed similar findings and, given the multifocality, brown tumors related to primary or secondary hyperparathyroidism was included in the differential diagnosis. A laboratory examination showed high total serum calcium (14.5 mg/dl) and low serum phosphorus and 25-hydroxyvitamin D levels. Primary hyperparathyroidism was suspected and confirmed by the elevated parathyroid hormone levels of 1453 pg/mL. At radiological work-up, using computed tomography, ultrasonography, and parathyroid subtraction technetium-99m sestamibi scintigraphy, a 4.5 × 2.5 × 3.2 cm mass emanating from the right lobe of his thyroid gland was detected, displaying extensive uptake in the right lower parathyroid gland. After appropriate medical support including hyperhydration and high doses of diuretics and diphosphonates, his laboratory profile normalized and he underwent total thyroidectomy with removal of the parathyroid glands. Our patient is now recovering 12 months after surgery, with normal values of serum parathyroid hormone and calcium levels. The lytic bone lesions have almost disappeared and no other additional orthopedic intervention was necessary.

Conclusions

The present case report emphasizes the need of inclusion of brown tumors in the differential diagnosis of multifocal osteolytic bone lesions, in order to avoid harmful surgical interventions. Laboratory testing of serum phosphate, calcium levels, and parathyroid hormone levels should always be included in the routine survey of patients with multifocal osteolytic lesions.

The impact of vitamin D status on hungry bone syndrome after surgery for primary hyperparathyroidism

OBJECTIVE

Prolonged hypocalcemia but normal intact parathyroid hormone (iPTH) levels after surgery for primary hyperparathyroidism (PHPT) are referred to as 'hungry bone syndrome' (HBS). The aim was to evaluate preoperative risk factors for HBS with a focus on the impact of 25-hydroxyvitamin D (25(OH)D) deficiency.

DESIGN

Patients having undergone initial successful surgery for sporadic PHPT within 6 years were considered for retrospective analysis.

METHODS

A total of 385 patients were evaluated, of whom 33 (8.6%) developed HBS influencing negatively the postoperative bone metabolism. All patients underwent biochemical evaluations two days before parathyroid surgery and were followed biochemically on a daily basis in the first postoperative week and thereafter at 8 weeks and 6 months.

CONCLUSIONS

No relationship was established between preoperative 25(OH)D deficiency and HBS. The only significant risk factor for HBS in multivariable analysis was high levels of preoperative iPTH. As HBS therefore cannot be predicted preoperatively, we recommend a consistent postoperative calcium and vitamin D supplementation to improve the bone metabolism.

Giant parathyroid adenoma associated with severe hypercalcemia in an adolescent patient

BACKGROUND

The objective of this study is to bring attention to the importance of differential diagnosis in adolescent patients with skeletal involvement and hypercalcemia.

CASE

A 17-year-old male patient with a complaint of severe leg pain was admitted to our hospital. Seven months before he had a fracture of his distal humerus after falling on to his left shoulder and was treated conservatively. Five months previously, he had a rupture of his quadriceps tendon. Magnetic resonance imaging (MRI) was performed for the quadriceps tendon rupture and was evaluated as polyostotic fibrous dysplasia (PFD). Doctors decided to operate for the ruptured tendon but they detected severe hypercalcemia in the pre-operative blood tests and noticed that the main disease was primary hyper-parathyroidisim (PHPT) which was caused by a giant parathyroid adenoma. Conclusions Giant parathyroid adenoma can present in adolescent patients with multiple bone lesions and severe hypercalcemia. PHPT should be considered in the differential diagnosis of pathological bone fractures and benign bone tumors in every age. This may prevent patients from miss or delayed diagnosis of PHPT.

Preoperative zoledronic acid therapy prevent hungry bone syndrome in patients with primary hyperparathyroidism

BACKGROUND

Hungry bone syndrome is a common complication of surgery for primary hyperparathyroidism in India which often leads to prolonged hospitalization. There are varying reports on the use and efficacy of bisphosphonates in the prevention of hungry bone syndrome.

METHODS

We retrospectively analyzed the effect of preoperative bisphosphonate therapy on rates of hungry bone syndrome in our patients with primary hyperparathyroidism. A total of 19 patients underwent surgery for primary hyperparathyroidism at our institute between January 2013 and June 2015 among whom eight did not receive preoperative bisphosphonates and 11 received intravenous zoledronic acid 4 mg, 24-48 h preoperatively.

RESULTS

There was no significant difference between the two groups with respect to age, gender, duration of symptoms, preoperative serum calcium, phosphorus, parathyroid hormone, alkaline phosphatase, and the presence of radiological evidence of hyperparathyroid bone disease also did not differ between the groups. Three out of the eight patients who did not receive preoperative zoledronic acid therapy had hungry bone syndrome but none in the zoledronic acid group. The prevalence of hungry bone syndrome tended to be lower in the zoledronic acid group (P = 0.058). The need for intravenous calcium and duration of postoperative hospital stay were significantly lesser in the zoledronic acid group.

CONCLUSION

Preoperative intravenous zoledronic acid significantly reduces the need for intravenous calcium therapy and duration of postoperative hospital stay and seems a promising option to reduce the rate of hungry bone syndrome in patients with primary hyperparathyroidism.

BROWN TUMOR OF BONE AS INITIAL MANIFESTATION OF PRIMARY HYPERPARATHYROIDISM

Primary hyperparathyroidism (PHPT) is characterized with primary hyperproduction of parathyroid hormone (PTH) by affected parathyroid glands and with a corresponding increase in concentration of extracellular calcium. Long-term development of PHPT through decades leads to calcium-related symptoms and distinct changes in the skeleton, kidneys, digestive tract and other organs. In the clinical picture of PHPT, granulomatous pseudo-tumors in bones are observed as a rare manifestation of the disease – these lesions, which could imitate malignancy, are called «brown tumors». The present publication that goes into details about a clinical diagnosis, in which a brown tumor became the primary manifestation of PHPT, may be useful for physicians across various fields.

A case of adolescent giant parathyroid adenoma presenting multiple osteolytic fractures and postoperative hungry bone syndrome

Primary hyperparathyroidism (PHPT) and postoperative hungry bone syndrome are very rare conditions in adolescents, and may be frequently misdiagnosed as a metastatic bone tumor. However, delay in diagnosis may lead to a fatal preoperative hypercalcemia and postoperative hypocalcemia. PHPT is a differential diagnosis of adolescent hypercalcemia and osteolytic fractures.

Brown tumor of the cervical spines: a case report with literature review

To report a rare case of axis brown tumor and to review literature of cervical spine brown tumor. Brown tumor is a rare bone lesion, incidence less than 5% in primary hyperparathyroidism. It is more common in secondary hyperparathyroidism with up to 13% of cases. Brown tumor reactive lesion forms as a result of disturbed bone remodeling due to long standing increase in parathyroid hormones. Cervical spine involvement is extremely rare, can be confused with serous spine lesions. To date, only four cases of cervical spine involvement have been reported. Three were due to secondary hyperparathyroidism. Only one was reported to involve the axis and was due to secondary hyperparathyroidism. This is the first reported case of axis brown tumor due to primary hyperparathyroidism. A case report of brown tumor is presented. A literature review was conducted by a Medline search of reported cases of brown tumor, key words: brown tumor, osteoclastoma and cervical lesions. The resulting papers were reviewed and cervical spine cases were listed then classified according to the level, cause, and management. Only four previous cases involved the cervical spine. Three were caused by secondary hyperparathyroidism and one was by primary hyperparathyroidism which involved the C6. Our case was the first case of C2 involvement of primary hyperparathyroidism and it was managed conservatively. Brown tumor, a rare spinal tumor that presents with high PTH and giant cells, requires a high level of suspicion.

Hungry bone syndrome: still a challenge in the post-operative management of primary hyperparathyroidism: a systematic review of the literature

Hungry bone syndrome (HBS) refers to the rapid, profound, and prolonged hypocalcaemia associated with hypophosphataemia and hypomagnesaemia, and is exacerbated by suppressed parathyroid hormone (PTH) levels, which follows parathyroidectomy in patients with severe primary hyperparathyroidism (PHPT) and preoperative high bone turnover. It is a relatively uncommon, but serious adverse effect of parathyroidectomy. We conducted a literature search of all available studies reporting a 'hungry bone syndrome' in patients who had a parathyroidectomy for PHPT, to identify patients at risk and address the pitfalls in their management. The severe hypocalcaemia is believed to be due to increased influx of calcium into bone, due to the sudden removal of the effect of high circulating levels of PTH on osteoclastic resorption, leading to a decrease in the activation frequency of new remodelling sites and to a decrease in remodelling space, although there is no good documentation for this. Various risk factors have been suggested for the development of HBS, including older age, weight/volume of the resected parathyroid glands, radiological evidence of bone disease and vitamin D deficiency. The syndrome is reported in 25-90% of patients with radiological evidence of hyperparathyroid bone disease vs only 0-6% of patients without skeletal involvement. There is insufficient data-based evidence on the best means to treat, minimise or prevent this severe complication of parathyroidectomy. Treatment is aimed at replenishing the severe calcium deficit by using high doses of calcium supplemented by high doses of active metabolites of vitamin D. Adequate correction of magnesium deficiency and normalisation of bone turnover are required for resolution of the hypocalcaemia which may last for a number of months after successful surgery. Preoperative treatment with bisphosphonates has been suggested to reduce post-operative hypocalcaemia, but there are to date no prospective studies addressing this issue.

Vertebral brown tumors causing neurologic compromise

OBJECTIVE

Brown tumors are nonneoplastic lesions that occur only in the setting of hyperparathyroidism. Although vertebral brown tumors are relatively rare pathologic entities, their incidence seems to be on the rise, as evidenced by multiple case reports published during the past four decades. An extensive review of these lesions is lacking in the literature. We present a case of paraparesis secondary to vertebral brown tumor followed by a detailed review of the literature.

METHODS

We performed a review of the literature to locate all reported cases to date of vertebral brown tumors resulting in neurologic sequelae. In addition, we present the case of a 33-year-old female with end-stage renal disease and previous subtotal parathyroidectomy who presented with acute-onset paraparesis from an expansile L1 brown tumor and was treated successfully by laminectomy and bracing.

RESULTS

Thirty cases of vertebral brown tumor resulting in neurologic deficit were located in our literature search. Most occurred in women (63%), those aged 40 to 49 years (27%), and in the thoracic spine (57%). Lesions occurred roughly equally in primary (47%) and secondary (53%) hyperparathyroidism. Most patients demonstrated either symptomatic or radiographic improvement after neurosurgical intervention and/or subtotal or total parathyroidectomy.

CONCLUSION

In patients presenting with a lytic vertebral lesion and known hyperparathyroidism or end-stage renal disease, brown tumor should be considered in the differential diagnosis. In select cases with minimal neurologic symptoms, parathyroidectomy may be warranted prior to neurosurgical intervention.

Brown tumor mimicking maxillary sinus mucocele as the first manifestation of primary hyperparathyroidism

We describe the first case of brown tumor mimicking a maxillary sinus mucocele as the first manifestation of the patient's primary hyperparathyroidism. A 34-year old woman presented with a 14 days history of elevation of the right orbit, retrobulbar pain and cheek anesthesia. The CT and MR evaluation showed a mass, initially described as mucocele of the right maxillary sinus. The laboratory studies revealed hyperparathyroidism. The patient underwent acute surgery, and the mass appeared clinically as mucocele. The histological examination of the resected lesion revealed changes representing either giant cell granuloma or brown tumor. The finding of hyperparathyroidism confirmed the diagnosis of brown tumor. To our knowledge, this is the first report of cystic brown tumor mimicking a mucocele of the maxillary sinus.

Mediastinal parathyroid carcinoma presenting with severe skeletal manifestations

Parathyroid carcinoma is a rare malignancy, accounting for about 1% of primary hyperparathyroidism. We report the case of a 23-year-old man who presented with poorly united mid-shaft fracture of the left femur with severe hypercalcaemia in the setting of 99 mTc sestamibi-avid lesions in the mediastinal and thoracic vertebrae. The patient underwent surgery, and histopathology revealed a low-grade parathyroid carcinoma. After surgery, the patient developed severe hungry bone syndrome requiring intensive calcium, magnesium and active vitamin D supplementation. A review of the literature was undertaken with regards to mediastinal parathyroid carcinoma, management of refractory hypercalcaemia in this setting and hungry bone syndrome.

The role of mast cells in parathyroid bone disease

Chronic hyperparathyroidism (HPT) is a common cause of metabolic bone disease. These studies investigated the underlying cellular and molecular mechanisms responsible for the detrimental actions of elevated parathyroid hormone (PTH) on the skeleton. Bone biopsies from hyperparathyroid patients revealed an association between parathyroid bone disease and increased numbers of bone marrow mast cells. We therefore evaluated the role of mast cells in the etiology of parathyroid bone disease in a rat model for chronic HPT. In rats, mature mast cells were preferentially located at sites undergoing bone turnover, and the number of mast cells at the bone-bone marrow interface was greatly increased following treatment with PTH. Time-course studies and studies employing parathyroid hormone-related peptide (PTHrP), as well as inhibitors of platelet-derived growth factor-A (PDGF-A, trapidil), kit (gleevec), and PI3K (wortmannin) signaling revealed that mature mast cell redistribution from bone marrow to bone surfaces precedes and is associated with osteitis fibrosa, a hallmark of parathyroid bone disease. Importantly, mature mast cells were not observed in the bone marrow of mice. Mice, in turn, were resistant to the development of PTH-induced bone marrow fibrosis. These findings suggest that the mast cell may be a novel target for treatment of metabolic bone disease.

Missed brown tumors in a young adult with decreased bone density

Brown tumors, a benign osteolytic process, are most commonly caused by hyperparathyroidism. Multiple bone involvement is relatively rare. There are many similarities in the radiologic and histological features of brown tumors and giant cell tumors (GCTs) of bone. Differentiation between the two lesions is dependent upon evaluation of serum biochemistry including serum calcium, phosphorous, and intact parathyroid hormone (I-PTH) levels. Herein, the case of a 32-year-old man with multiple osteolytic lesions of the left tibia and fibula as well as the fourth metacarpal bone of the left hand, previously misdiagnosed with multiple GCTs, is presented. Based on the radiographic findings and biochemistry results in a young adult patient, brown tumor was suspected and subsequently definitively diagnosed.

Spinal cord compression secondary to brown tumour in a patient on long-term haemodialysis: a case report

Brown tumours may occur secondary to hyperparathyroidism in patients with chronic renal failure (CRF). Diagnosing a spinal brown tumour causing cord compression requires a high index of suspicion. We report a 65-year-old woman, who had been on haemodialysis for CRF for over 10 years, who presented with leg weakness and back pain over the thoracolumbar junction. She had a brown tumour at T8 causing subacute spinal cord compression. Ambulation was regained after surgical decompression and stabilisation. Adherence to the National Kidney Foundation guidelines in the management of patients with CRF may prevent renal osteodystrophy. Treatment of spinal brown tumour depends on the severity of the neurological deficit. Remineralization is expected after correction of the parathyroid level, thus negating the need for total excision of the parathyroid glands.

Unresolved lytic lesions following parathyroidectomy in a patient with chronic renal failure

With advances in the treatment of patients with chronic renal failure, their life expectancy has increased. In turn, the prevalence of osteitis fibrosa cystica, a manifestation of secondary hyperparathyroidism, and β2 microglobulin amyloidosis, a result of long-term haemodialysis, has risen. While both conditions share similar radiological features, their management is very different.

We present the case of a patient with renal failure who had been receiving haemodialysis for over 20 years. Lytic lesions had been observed in the proximal part of both femurs for ten years. A presumptive diagnosis of osteitis fibrosa cystica was made. However, no regression of the lesions occurred after parathyroidectomy. The patient subsequently developed sequential pathological fractures through the lesions, for which bilateral total hip replacements were performed. Histology of the lesions revealed that the patient was in fact suffering from amyloidosis.

In patients with chronic renal failure, osseous amyloidosis is a highly probable differential diagnosis, especially if no regression of a lytic lesion is observed after parathyroidectomy.

Brown tumor of the fibula: unusual presentation of an uncommon manifestation. Report of a case and review of the literature

Brown tumors are erosive bony lesions caused by rapid osteoclastic activity and peritrabecular fibrosis due to hyperparathyroidism, resulting in a local destructive phenomenon. Although brown tumors are the most pathognomonic sign of hyperparathyroidism, they are very rarely observed at present as a result of early detection of hypercalcemia and elevated parathyroid hormone levels. The rare appearance of this entity in everyday practice is troublesome for both patients and physicians, because whenever it emerges, diagnosis could be mistaken for a giant cell tumor of the bone. However, clinical, biochemical, and radiologic findings can easily guide the diagnosis if one considers the full continuum of findings and their association with subject's medical history, instead of focusing only on bone lesion. In this report we present a case of brown tumor in the fibula with a short literature review, whose aggressive presentation and unawareness of the skeletal findings of hyperparathyroidism puzzled the caring doctors. This case illustrates the need for continuous vigilance of any physician, regardless of his specialty or his position in medical services structures.

Bone Tumor Mimics: Avoiding Misdiagnosis

Whether discovered incidentally or as part of a focused diagnostic evaluation, the finding of a benign osseous lesion that has radiologic features resembling a bone tumor is not uncommon. Some of the more common benign and nonneoplastic entities that can sometimes be confused with tumors are the following: cortical desmoid, Brodie abscess, synovial herniation pit, pseudocyst, enostosis, intraosseous ganglion cyst, fibrous dysplasia, stress fracture, avulsion fracture (healing stage), bone infarct, myositis ossificans, brown tumor, and subchondral cyst. Accurate diagnosis and management of these lesions require a basic understanding of their epidemiology, clinical presentations, anatomic distributions, imaging features, differential considerations, and therapeutic options. This in-depth review of 13 potential bone tumor mimics will assist the radiologist in correctly identifying these benign lesions and in avoiding misdiagnosis and related morbidity. This review will also aid the radiologist in making appropriate recommendations to the referring physician for management or further imaging.

Analysis of the diagnostic presentation profile, parathyroidectomy indication and bone mineral density follow-up of Brazilian patients with primary hyperparathyroidism

Primary hyperparathyroidism is an endocrine disorder with variable clinical expression, frequently presenting as asymptomatic hypercalcemia in Western countries but still predominantly as a symptomatic disease in developing countries. The objective of this retrospective study was to describe the diagnostic presentation profile, parathyroidectomy indication and post-surgical bone mineral density follow-up of patients with primary hyperparathyroidism seen at a university hospital. We found 115 patients (92 women, median age 56 years) with primary hyperparathyroidism diagnosed during the last 20 years. We defined symptomatic patients based on the presence of any classical symptom affecting bone, kidney or the neuromuscular system. Surgical criteria followed the guidelines of the National Institutes of Health regarding asymptomatic primary hyperparathyroidism. Symptomatic patients and patients meeting surgical criteria for parathyroidectomy were 66 and 93% of the sample, respectively. Median calcium and parathyroid hormone values were 11.9 mg/dL and 189 pg/mL, respectively. After surgical treatment, 97% of patients were cured, with increases in bone mineral density of 19.4% in the lumbar spine and 15.7% in the femoral neck 3 years after surgery. Greater bone mass increases were detected in pre-menopausal women, men, and in symptomatic and younger patients, both in the lumbar spine and femoral neck. Our results support the previous findings of a predominantly symptomatic disease with a presentation profile that could be mainly related to a delayed diagnosis. Nevertheless, genetic and racial backgrounds, and nutritional factors such as calcium and vitamin D deficiency may play a role in the clinical presentation of primary hyperparathyroidism of Brazilian patients.

Indian primary hyperparathyroidism patients with parathyroid carcinoma do not differ in clinicoinvestigative characteristics from those with benign parathyroid pathology

INTRODUCTION

No foolproof preoperative diagnostic indicators of parathyroid carcinoma (PC) exist in absence of nonskeletal metastases. Palpable parathyroid tumor, advanced skeletal and renal manifestations, and very high serum calcium and parathyroid hormone levels are considered strong predictors. Most of these features are common in Indian primary hyperparathyroidism (PHPT) patients although only few have PC. The aim of this study was to identify dependable clinicoinvestigative predictors of PC in Indian PHPT patients.

MATERIALS AND METHODS

Clinical, biochemical, radiological, and densitometric attributes of 100 PHPT patients who underwent successful parathyroidectomy (1990-2004) were studied. Various parameters of patient groups with parathyroid adenoma (n = 84), primary hyperplasia (n = 12), and carcinoma (n = 4) were compared using ANOVA, with P value < 0.05 considered significant.

RESULTS

Mean age of patients was 37.4 years, with no difference in the 3 groups (P = 0.92). Patients in 3 groups had comparably severe bone disease; 36 had coexistent renal disease. Two patients with PC and 27 (32%) with adenoma had palpable parathyroid tumor. None of the biochemical parameters predicted malignant pathology. Mean tumor weight (milligram) in carcinoma patients (15,080 +/- 5,638.02) was significantly higher than those with adenoma (5,724 +/- 1,257.9) (P = 0.002). Postoperative course and recovery in carcinoma patients were similar to those with adenoma. In follow-up (mean: 33 months), none of the adenoma patients were found to have persistent/recurrent PHPT attributable to missed PC.

CONCLUSION

Indian patients with parathyroid adenoma, hyperplasia, and carcinoma were not found to differ in their clinical, biochemical, and pathological characteristics except for significantly higher tumor weight in the carcinoma group.

Implantation of parathyroid carcinoma along fine needle aspiration track

INTRODUCTION

Fine needle aspiration cytology is not a commonly employed diagnostic modality in the diagnosis of parathyroid tumors.

CASE REPORT

A 28 year old lady being followed-up for 5 years after en bloc resection of a parathyroid carcinoma presented with a nodule in the lower neck, away from the parathyroidectomy scar. The 1 cm isolated nodule was located in the muscular and subcutaneous plane and corresponded to the needle track of FNA performed on a neck nodule before the parathyroidectomy. On evaluation, she had mild hypercalcemia and high normal serum parathyroid hormone levels. FNAC and histology including immunohistochemistry for Chromogranin A after local excision of the nodule confirmed the nodule to be a recurrent parathyroid carcinoma along the needle track.

DISCUSSION

To the best of the authors' knowledge, this is only the second case of needle track implantation after FNA in parathyroid carcinoma reported to date. This case highlights the risk of engraftment of parathyroid tissue after FNA and cautions against the use of FNA as a preoperative diagnostic modality for the evaluation of parathyroid lesions.

Regression of skeletal manifestations of hyperparathyroidism with oral vitamin D

CONTEXT

Parathyroidectomy is the only effective therapy for osteitis fibrosa cystica in hyperparathyroidism.

OBJECTIVE

The objective of this study was to describe the changes of skeletal and nonskeletal manifestations in a patient with hyperparathyroidism and renal failure after oral vitamin D therapy.

DESIGN

This was a descriptive case report.

SETTING

The patient was followed up in a referral center.

PATIENT

A 55-yr-old male patient with moderate renal failure was referred for expansile lytic lesions affecting several ribs and the spinous process of T12. His creatinine was 1.8 mg/dl; calcium, 8.9 mg/dl; PTH, 666 pg/ml; and 1,25 dihydroxy-vitamin D, 27 pg/ml. Bone mineral density (BMD) Z-scores by dual-energy x-ray absorptiometry were -4.1 at the spine, -1.7 at the hip, and -4.3 at the forearm.

MAIN OUTCOME MEASURES

The main outcome measures were the skeletal manifestations of hyperparathyroidism.

RESULTS

At 10 months of therapy, calcium level was 10 mg/d, PTH level declined to 71 pg/ml, and BMD increased by 12% at the spine and 18% at the hip. Computerized tomography (CT) cuts revealed marked regression in the lytic lesions. At 2 yr, BMD increased by an additional 6% at the spine, and there were no further changes in the lytic lesions by CT. The vitamin D receptor genotype using the restriction enzymes Bsm1, Taq1, and Apa1 was Bb, tt, and AA.

CONCLUSIONS

We showed regression of severe skeletal abnormalities of hyperparathyroidism documented by serial CT images in response to oral vitamin D therapy. It is possible that the vitamin D receptor genotype of the patient modulated this response.

Evidence that the cells responsible for marrow fibrosis in a rat model for hyperparathyroidism are preosteoblasts

We examined proliferation of cells associated with PTH-induced peritrabecular bone marrow fibrosis in rats as well as the fate of those cells after withdrawal of PTH. Time-course studies established that severe fibrosis was present 7 d after initiation of a continuous sc PTH infusion (40 microg/kg.d). To ascertain cell proliferation, rats were coinfused for 1 wk with PTH (treated) or vehicle (control) and [3H]thymidine (1.5 mCi/rat). Groups of control and treated rats were killed immediately (d 0) and 1 wk (d 7) later. Few osteoblasts (Obs) and osteocytes in treated and control groups were radiolabeled on d 0. Peritrabecular cells expressing a fibroblastic (Fb) phenotype and surrounded by an extracellular matrix were not present in controls on either d 0 or d 7. Multiple cell layers of Fbs lined most (70%) of the bone surface on d 0 in treated rats and nearly all (85%) of the Fbs were radiolabeled. Fbs had entirely disappeared from bone surfaces on d 7. Eighty-five percent of the Obs on and 73% of the osteocytes within the active remodeling sites were radiolabeled. Immunohistochemistry revealed that Fbs induced by PTH treatment produced osteocalcin, osteonectin, and core binding factor-alpha1. These data provide compelling evidence that Fbs recruited to bone surfaces in response to a continuous PTH infusion undergo extensive proliferation, express osteoblast-specific proteins, and produce an extracellular matrix that is similar to osteoid. After restoration of normal PTH levels, Fbs differentiated to Obs, providing further evidence that Fbs are preosteoblasts.

Leontiasis ossea in a patient with hyperparathyroidism secondary to chronic renal failure

Osteitis fibrosa describes the bone changes seen in renal osteodystrophy secondary to longstanding hyperparathyroidism. We report a 19-year-old man with longstanding chronic renal failure with a severe form of osteitis fibrosa affecting the jaws and other maxillofacial bones causing bizarre facial and dental deformity in a patient-uraemic leontiasis ossea.

Hyperparathyroid crisis in a pediatric patient

Primary hyperparathyroidism is rarely found in the pediatric population. Delays in diagnosis due to vague symptoms can lead to severe disease manifestations such as osteitis fibrosa cystica. We report a rare case of primary hyperparathyroidism in a 13-year-old girl who presented with a pathological femur fracture and numerous brown tumors.