Fluoride-related bone disease associated with habitual tea consumption.

Acquired osteosclerosis is a rare disorder of bone formation but an important consideration in adults with sclerotic bones or elevated bone density results. In such patients, malignancy, hepatitis C, and fluorosis should all be considered when making a diagnosis. We describe 4 patients evaluated at our Metabolic Bone Disease Clinic from May 1, 1997, to July 1, 2006, whose bone disorders resulted from chronic fluoride exposure due to excessive tea intake. Three of these patients had toxic serum fluoride levels (> 15 micromol/L). Although the clinical presentation of the patients varied, all 4 had an unexpectedly elevated spine bone mineral density that was proportionately higher than the bone mineral density at the hip. Other clinical features included gastrointestinal symptoms such as nausea, vomiting, and weight loss; lower extremity pain sometimes associated with stress fractures of the lower extremities; renal insufficiency; and elevated alkaline phosphatase levels. Readily available, tea often contains high levels of fluoride. Obsessive-compulsive drinking behaviors and renal insufficiency may predispose to excessive fluoride consumption and accumulation. The current cases show that fluoride-related bone disease is an important clinical consideration in patients with dense bones or gastrointestinal symptoms and a history of excessive tea consumption. Furthermore, fluoride excess should be considered in all patients with a history of excessive tea consumption, especially due to its insidious nature and nonspecific clinical presentation.

Pathogenesis of Graves' ophthalmopathy: the role of autoantibodies.

The clinical manifestations of Graves' ophthalmopathy (GO) stem from a combination of increased orbital fat and extraocular muscle volume within the orbital space. Fibroblasts residing within orbital tissues are thought to be targets of autoimmune attack in the disease. Thyrotropin receptor (TSHr) mRNA and functional protein have been demonstrated in orbital fibroblasts from both normal individuals and GO patients, with higher levels present in the latter. Autoantibodies directed against TSHr or the insulin-like growth factor-1 (IGF-1) receptor have been implicated in GO pathogenesis. Evidence from our laboratory suggests that monoclonal TSHr autoantibodies (TRAbs) are potent stimulators of adipogenesis in GO orbital cells. Therefore, it is possible that circulating TRAbs in Graves' patients both stimulate overproduction of thyroid hormones and increase orbital adipose tissue volume. Antibodies to the IGF-1 receptor appear to impact GO pathogenesis through recruitment and activation of T-cells and stimulation of hyaluronan production, processes that play key roles in the development of inflammation and increased orbital tissue swelling. Although originally thought to represent another causative agent, antibodies to extraocular muscles are now generally thought to be secondary to extraocular muscle inflammation and damage.

Acute pancreatitis in primary hyperparathyroidism: a population-based study.

CONTEXT: The association between acute pancreatitis and primary hyperparathyroidism (PHPT) is controversial. OBJECTIVE: The aim of the study was to address the incidence and disease characteristics of acute pancreatitis in PHPT from a large inception cohort of community residents. DESIGN AND SETTING: Patients with acute pancreatitis were identified in an Olmsted County, Minnesota, cohort of PHPT subjects diagnosed from 1965-2001 and compared to matched control subjects. MAIN OUTCOME MEASURES: The estimated rate of developing acute pancreatitis was calculated by person-years method. Cox models assessed the effect of PHPT disease status on the development of acute pancreatitis. RESULTS: Of 684 patients with PHPT, 10 patients (1.5%) developed acute pancreatitis, compared to 32 of 1364 control patients (2.3%). The estimated rate of development of acute pancreatitis in PHPT was 114 per 100,000 person-years, compared to 140 per 100,000 person-years in control subjects (P = 0.56). The estimated hazard ratio of acute pancreatitis for PHPT relative to the control subjects was 0.84 (P = 0.89). The majority of subjects with PHPT and acute pancreatitis were women (n = 7), and the mean age was 70.6 yr at the time of acute pancreatitis. PHPT was present an average of 137 months before the development of acute pancreatitis, and contributing causes for acute pancreatitis were in identified in four patients. Maximal serum calcium levels in PHPT were not significantly associated with the development of acute pancreatitis. CONCLUSIONS: Acute pancreatitis was not increased in community patients with PHPT, and therefore, there does not appear to be a causal relationship between PHPT and acute pancreatitis.

Evidence for enhanced Thy-1 (CD90) expression in orbital fibroblasts of patients with Graves' ophthalmopathy.

BACKGROUND: Thy-1 is a surface protein that defines functionally distinct subpopulations of fibroblasts, with those lacking the antigen being capable of adipogenesis. Because increased fat cell development is a hallmark of the orbit in Graves' ophthalmopathy (GO), we wished to compare baseline Thy-1 expression in orbital fibroblasts from GO patients and normal individuals, and determine whether levels of the protein might be impacted by adipogenesis following peroxisome proliferator activator-gamma ligation. METHODS: Orbital adipose/connective tissue specimens were obtained from euthyroid patients undergoing orbital decompression surgery for severe GO (n = 9) and from normal individuals (n = 9). Thy-1 mRNA and protein levels were assessed in tissue specimens and in orbital fibroblast cultures at baseline using RT-PCR, quantitative immunofluorescent staining, and flow cytometry using a specific Thy-1 mouse anti-human CD90/Thy-1 monoclonal antibody. In addition, some orbital fibroblast cultures were treated with rosiglitazone (1 microL/mL; 2 nM) or control for 10 days in culture. RESULTS: We found that Thy-1 mRNA and protein expression was higher in uncultured GO connective/adipose tissue specimens (3.8-fold; 0.835 +/- 0.116 relative expression) compared with normal (0.22 +/- 0.062; p = 0.002) and in cultured orbital fibroblasts from GO patients (3.3-fold; 9.28 +/- 1.82 relative expression) compared with normal cultures (2.80 +/- 0.42; p = 0.013). Adipocyte differentiation had no effect on Thy-1 expression. Flow cytometry and immunofluorescent staining showed increased numbers of Thy-1-positive cells in the GO (mean 77.9 + 4.09%; range 66.5-84.8%) compared with the normal fibroblast cultures (66.8 + 1.6%; range 63.3-71.0% positive; p = 0.046), as well as higher levels of expression on the positive cells. CONCLUSIONS: Increased Thy-1 expression in GO orbital tissues and cultures is likely a consequence of the orbital disease process, reflecting both the presence of increased numbers of Thy-1-positive cells and higher expression on those cells. Adipogenesis itself does not appear to impact Thy-1 expression. Increased expression of this protein in GO could represent an adaptive response to cell injury, in effect limiting disease progression within the orbital adipose/connective tissues.

Comparison of ultrasound-guided fine-needle aspiration biopsy with core-needle biopsy in the evaluation of thyroid nodules.

OBJECTIVE: To compare the diagnostic rate of ultra-sound-guided fine-needle aspiration biopsy (FNAB) with the diagnostic rate of combined FNAB and core-needle biopsy in the evaluation of nodular thyroid disease. METHODS: We performed a retrospective case-control study by reviewing charts of patients who underwent ultra-sound-guided FNAB and core-needle biopsy of the thyroid at a tertiary referral center from January 1999 to December 2001. Results were classified as diagnostic (negative, suspicious, or positive for malignancy) or nondiagnostic. These findings were compared with an age- and sex-matched control group who underwent only FNAB. Complications between the groups were reviewed. RESULTS: The patient group consisted of 320 patients who underwent 340 ultrasound-guided fine-needle aspiration and core-needle biopsies of the thyroid; the control group consisted of 311 patients who underwent 340 FNABs. There was no significant difference in the nondiagnostic rates between groups--12.9% in patients who had FNAB-only compared with 10.9% in patients who had both procedures (proportion difference, -2.1%; 95% confidence interval, -7.0% to 2.9%; P = .41). There was a trend towards an increased incidence of hematoma and infection in the core biopsy group. In the group that underwent FNAB and core-needle biopsies, 10 patients (3.1%) developed biopsy-specific complications (hematomas in 8 patients, biopsy site infections in 2 patients). In the FNAB-only group, 3 patients (1.0%) developed hematomas; there was no incidence of infection. CONCLUSIONS: In the evaluation of thyroid nodules, the addition of core-needle biopsies to FNAB confers little benefit in decreasing the nondiagnostic rates and may be associated with increased complications. Core-needle biopsies should not be routinely performed in the evaluation of thyroid nodules, but rather, patient selection for the more invasive core biopsy should be done judiciously.

Suppressibility of parathyroid hormone in primary hyperparathyroidism.

OBJECTIVE: To describe an unusual case of pathologically confirmed primary hyperparathyroidism in a patient presenting with severe hypercalcemia and an undetectable parathyroid hormone (PTH) level. METHODS: We present a detailed case report and outline the serial laboratory findings. In addition, the possible causes of low serum PTH levels in the setting of primary hyperparathyroidism are discussed. RESULTS: A 16-year-old female patient presented with severe epigastric pain, found to be attributable to acute pancreatitis. At hospital admission, her serum calcium concentration was high (14.0 mg/dL); the patient also had a normal serum phosphorus level of 3.6 mg/dL and an undetectable PTH level (<0.2 pmol/L). An evaluation for non-PTH-mediated causes of hypercalcemia revealed a partially suppressed thyroid-stimulating hormone concentration and a below normal 1,25-dihydroxyvitamin D level, consistent with her suppressed PTH. One week after the patient was dismissed from the hospital, repeated laboratory studies showed a serum calcium value of 11.1 mg/dL, a serum phosphorus level of 2.8 mg/dL, and an elevated PTH concentration of 11.0 pmol/L, consistent with primary hyperparathyroidism. A repeated 1,25-dihydroxyvitamin D measurement was elevated. A parathyroid scan showed a parathyroid adenoma in the left lower neck area, and she subsequently underwent successful surgical resection of a pathologically confirmed parathyroid adenoma. CONCLUSION: This case demonstrates that the serum PTH level can be suppressed in patients with primary hyperparathyroidism. Moreover, it emphasizes the need for careful evaluation of the clinical context in which the PTH measurement is determined. Consideration should be given to repeating measurement of PTH and serum calcium levels when the initial laboratory evaluation of hypercalcemia is unclear because dynamic changes in calcium metabolism may occur in the presence of secondary contributing factors.