Impact of severity, duration, and etiology of hyperthyroidism on bone turnover markers and bone mineral density in men

<p>Abstract</p> <p>Background</p> <p>Hyperthyroidism is accompanied by osteoporosis with higher incidence of fracture rates. The present work aimed to study bone status in hyperthyroidism and to elucidate the impact of severity, duration, and etiology of hyperthyroidism on biochemical markers of bone turnover and bone mineral density (BMD).</p> <p>Methods</p> <p>Fifty-two male patients with hyperthyroidism, 31 with Graves' disease (GD) and 21 with toxic multinodular goiter (TNG), with an age ranging from 23 to 65 years were included, together with 25 healthy euthyroid men with matched age as a control group. In addition to full clinical examination, patients and controls were subjected to measurement of BMD using dual-energy X-ray absorptiometery scanning of the lower half of the left radius. Also, some biochemical markers of bone turnover were done for all patients and controls.</p> <p>Results</p> <p>Biochemical markers of bone turnover: included serum bone specific alkaline phosphatase, osteocalcin, carboxy terminal telopeptide of type l collagen also, urinary deoxypyridinoline cross-links (DXP), urinary DXP/urinary creatinine ratio and urinary calcium/urinary creatinine ratio were significantly higher in patients with GD and TNG compared to controls (P < 0.01). However, there was non-significant difference in these parameters between GD and TNG patients (P > 0.05). BMD was significantly lower in GD and TNG compared to controls, but the Z-score of BMD at the lower half of the left radius in patients with GD (-1.7 ± 0.5 SD) was not significantly different from those with TNG (-1.6 ± 0.6 SD) (>0.05). There was significant positive correlation between free T3 and free T4 with biochemical markers of bone turnover, but negative correlation between TSH and those biochemical markers of bone turnover. The duration of the thyrotoxic state positively correlated with the assessed bone turnover markers, but it is negatively correlated with the Z-score of BMD in the studied hyperthyroid patients (r = -0.68, P < 0.0001).</p> <p>Conclusion</p> <p>Men with hyperthyroidism have significant bone loss with higher biochemical markers of bone turnover. The severity and the duration of the thyrotoxic state are directly related to the derangement of biochemical markers of bone turnover and bone loss.</p

Diagnostic criteria for diabetes revisited: making use of combined criteria

BACKGROUND: Existing cut-offs for fasting plasma glucose (FPG) and post-load glucose (2hPG) criteria are not equivalent in the diagnosis of diabetes and glucose intolerance. Adjusting cut-offs of single measurements have not helped so we undertook this project to see if they could be complementary. METHODS: We performed oral glucose tolerance tests and mean levels of hemoglobin A1c (HbA1c) measurements on 43 patients referred to a diabetes clinic for possible diabetes. Results of single and combined use of the FPG and 2hPG criteria were evaluated against the levels of HbA1c and results re-interpreted in the light of existing reports in the literature. RESULTS: Our results confirm that the FPG and the 2hPG, being specific and sensitive respectively for the presence of glucose intolerance or diabetes, are not equivalent. They are shown to be indeed complementary and a re-definition of diagnostic criteria based on their combined use is proposed. CONCLUSIONS: We conclude that altering single measurement cut-offs for the diagnosis of diabetes and altered glucose tolerance will not result in better outcomes. We present the case for a combined criteria in the diagnosis and definition of diabetes with a FPG≥7 mmol/L AND 2-hour glucose ≥7.8 mmol/L being used to define diabetes while a FPG<7 mmol/L AND 2-hour glucose <7.8 mmol/L being used to define normality. Discordant values will define impaired glucose tolerance (IGT). This proposal requires prospective evaluation in a large cohort

Spironolactone for the treatment of hypercalciuric hypocalcemia

A patient with hypocalcemia and hypomagnesemia, and renal wasting of both cations, is presented. This patient had a dramatic calcium response to treatment with spironolactone. The possible diagnoses and mechanisms of response are discussed. It is concluded that the patient had a calcium-sensing receptor mutation, and that treatment with spironolactone induced an effect on renal handling of calcium in this condition. It is suggested that this treatment be tried in other similar patients

Relationship between cortisol increment and basal cortisol: Implications for the low-dose short adrenocorticotropic hormone stimulation test

BACKGROUND: We analyzed the low-dose (1 microg) rapid adrenocorticotropic hormone test (LDST) in 17 patients with a normal hypothalamic-pituitary-adrenal axis to determine reference intervals for the LDST on the basis of poststimulation cortisol increments. METHODS: We analyzed test results for 17 patients (14 females and 3 males; age range, 18-46 years) who had received a 2-mL aliquot of low-dose (1 microg) adrenocorticotropic hormone prepared from one 250-microg vial of Synacthen diluted in 500 mL of sterile normal saline solution. Sampling took place at 0, 20, 30, and 60 min post stimulation. The cortisol increment was plotted against basal cortisol. RESULTS: We observed a marked interdependence of the basal cortisol concentration with the increase in cortisol concentration. The relationship was inverse and linear with the best fit observed at 30 min post stimulation. The lower 95% prediction limit for basal cortisol at the zero increment was 400 nmol/L with a mean concentration of 600 nmol/L. CONCLUSIONS: We propose that a peak cortisol concentration 600 nmol/L confirm normal adrenal function. Repeat analyses with larger sample sizes are warranted to confirm these observations