Prevalence of less severe hypercortisolism in fractured patients admitted in an outpatient clinic for metabolic bone diseases

PURPOSE

To evaluate the prevalence of less severe hypercortisolism (LSH) in fractured patients, and its association with hypertension, hyperglicemia, dyslipidemia, and obesity.

METHOD

From July 2015 to October 2018 we enrolled all fractured patients admitted in our outpatient center for metabolic bone diseases, after exclusion of patients with secondary osteoporosis apart from diabetes and taking drugs known to affect bone metabolism. In all enrolled patients we collected data regarding gonadal status, history of diabetes, high blood pressure, dyslipidemia, and measured blood pressure, lipid profile, fasting glycaemia. Bone mass was measured with DXA at lumbar spine and femoral neck and the presence of fractures was evaluated with X-ray of thoracic and lumbar spine. All patients performed twice, 1 mg overnight dexametasone suppression test (DST) and, as confirmatory, 2day low-dose DST for diagnosing hypercortisolism.

RESULTS

We enrolled 101 fractured patients (75 females, 26 males), aged 65 ± 10.3 years. Five out of 101 (5.0%) patients were diagnosed as LSH. Fifty-five (54.5%) out of 101 were hypertensive, 57 (56.4%) dyslipidemic, 17 (16.8%) hyperglicaemic, 28(27.7%) obese patients. LSH tended to be associated to blood hypertension [5/5 vs 50/96 (Fisher exact test, p = 0.06) hypertensive patients]. Four out five LSH patients were hypogonadic.

CONCLUSIONS

Our study confirms that a nonnegligible percentage of fractured subjects actually presents an unrecognized hypercortisolism. Accordingly, regardless of age, we suggest to screen for hypercortisolism all patients with established osteoporosis and in particular hypertensive subjects.

Bone involvement and mineral metabolism in Williams' syndrome

CONTEXT

The previous studies suggested a possible increased risk of hypercalcaemia and reduced bone mineral density (BMD) in Williams' syndrome (WS). However, an extensive study regarding bone metabolism has never been performed.

OBJECTIVE

To investigate bone health in young adults with WS.

DESIGN

Cross-sectional study.

SETTINGS

Endocrinology and Metabolic Diseases and Medical Genetic Units.

PATIENTS

29 WS young adults and 29 age- and sex-matched controls.

MAIN OUTCOME MEASURES

In all subjects, calcium, phosphorus, bone alkaline phosphatase (bALP), parathyroid hormone (PTH), 25-hydroxyvitamin D (25OHVitD), osteocalcin (OC), carboxyterminal cross-linking telopeptide of type I collagen (CTX), 24-h urinary calcium and phosphorus, femoral-neck (FN) and lumbar-spine (LS) BMD and vertebral fractures (VFx) were assessed. In 19 patients, serum fibroblast growth factor-23 (FGF23) levels were measured.

RESULTS

WS patients showed lower phosphorus (3.1 ± 0.7 vs 3.8 ± 0.5 mg/dL, p = 0.0001) and TmP/GFR (0.81 ± 0.32 vs 1.06 ± 0.25 mmol/L, p = 0.001), and an increased prevalence (p = 0.005) of hypophosphoremia (34.5 vs 3.4%) and reduced TmP/GFR (37.9 vs 3.4%). Moreover, bALP (26.3 ± 8.5 vs 35.0 ± 8.0 U/L), PTH (24.5 ± 12.6 vs 33.7 ± 10.8 pg/mL), OC (19.4 ± 5.3 vs 24.5 ± 8.7 ng/mL), and FN-BMD (- 0.51 ± 0.32 vs 0.36 ± 0.32) were significantly lower (p < 0.05), while CTX significantly higher (401.2 ± 169.3 vs 322.3 ± 122.4 pg/mL, p < 0.05). Serum and urinary calcium and 25OHVitD levels, LS-BMD and VFx prevalence were comparable. No cases of hypercalcemia and suppressed FGF23 were documented. Patients with low vs normal phosphorus and low vs normal TmP/GFR showed comparable FGF23 levels. FGF23 did not correlate with phosphorus and TmP/GFR values.

CONCLUSIONS

Adult WS patients have reduced TmP/GFR, inappropriately normal FGF23 levels and an uncoupled bone turnover with low femoral BMD.

High serum osteopontin levels are associated with prevalent fractures and worse lipid profile in post-menopausal women with type 2 diabetes

PURPOSE

Patients with type 2 diabetes (T2DM) have increased fracture risk. Osteopontin (OPN) is a protein involved in bone remodeling and inflammation. The aim of this study was to evaluate the association of OPN with fracture prevalence and with metabolic parameters in post-menopausal women with T2DM.

METHODS

Sixty-four post-menopausal women with T2DM (age 67.0 ± 7.8 years, diabetes duration 8.9 ± 6.7 years), enrolled in a previous study, were followed up (3.6 ± 0.9 years). Previous fragility fractures were recorded. The FRAX score (without BMD) was calculated and biochemical parameters (plasma glucose, HbA1c, lipid profile and renal function) were assessed. Serum 25OH-vitamin D, calcium, PTH and OPN were evaluated at baseline. The association between OPN and fracture prevalence at baseline was evaluated by a logistic model.

RESULTS

OPN levels were higher in patients with previous fractures (n.25) than in patients without previous fractures at baseline (n.39) (p = 0.006). The odds of having fractures at baseline increased by 6.7 (1.9-31.4, 95% CI, p = 0.007) for each increase of 1 ng/ml in OPN levels, after adjustment for vitamin D and HbA1c levels. Fracture incidence was 4.7%. Higher OPN associated with a decrease in HDL-cholesterol (p = 0.048), after adjustment for age, basal HDL-cholesterol, basal and follow-up HbA1c and follow-up duration. 25OH-vitamin D associated with an increase in FRAX-estimated probability of hip fracture at follow-up (p = 0.029), after adjustment for age, 25OH-vitamin D and time.

CONCLUSIONS

In post-menopausal women with T2DM, OPN might be a useful marker of fracture and worse lipid profile.

Bone damage in type 2 diabetes mellitus

This review focuses on the mechanisms determining bone fragility in patients with type 2 diabetes mellitus (T2DM). Despite bone mineral density (BMD) is usually normal or more often increased in these patients, fracture incidence is high, probably because of altered bone "quality". The latter seems to depend on several, only partly elucidated, mechanisms, such as the increased skeletal content of advanced glycation end-products causing collagen deterioration, the altered differentiation of bone osteogenic cells, the altered bone turnover and micro-architecture. Disease duration, its severity and metabolic control, the type of therapy, the presence or absence of complications, as like as the other known predictors for falls, are all relevant contributing factors affecting fracture risk in T2DM. In these patients the estimate of fracture risk in the everyday clinical practice may be challenging, due to the lower predictive capacity of both BMD and risk factors-based algorithms (e.g. FRAX).

Effect of a single oral dose of 600,000 IU of cholecalciferol on muscle strength: a study in young women

BACKGROUND

The effect of a single large oral dose of vitamin D on muscle function in young people with vitamin D deficiency has not been investigated so far.

AIM

We evaluated the effect of a single oral dose of 600,000 IU of cholecalciferol on muscle strength.

SUBJECTS AND METHODS

Eighteen young women with vitamin D deficiency received a single oral dose of 600,000 IU of cholecalciferol. We evaluated changes in maximal voluntary contraction (MVC) and speed of contraction (S) in response to cholecalciferol by using an hand held dynamometer at 3, 15, 30, 60 and 90 days, compared to baseline.

RESULTS

We observed no significant change in MVC and S values, a significant increase of 25-hydroxyvitamin D [25(OH)D] and 1,25-dihydroxyvitamin D [1,25(OH)2D] and a significant decrease in serum parathyroid hormone (PTH) (p<0.001 for all). A significant correlation was found between MVC and S and serum phosphorus (P) after supplementation (p<0.02 and p<0.05, respectively). Conversely, we observed no association between the parameters of muscle strength and 25(OH)D, ionized calcium (Ca2+), PTH and 1,25(OH)2D.

CONCLUSIONS

A single dose of 600,000 IU of cholecalciferol does not directly enhance handgrip strength in young women with vitamin D deficiency. More studies are needed on the indirect effect of the hormone on muscle.

Vitamin D and parameters of calcium homeostasis in inpatients with and without Type 2 diabetes mellitus

AIM

We investigated inpatients with and without Type 2 diabetes mellitus, aged over 60 yr, to compare their vitamin D status and calcium homeostatic parameters.

MATERIALS AND METHODS

We studied 140 patients consecutively admitted to our Internal Medicine Unit during the year 2010 (61 from November to April, 79 from May to October). The sample encompassed 70 patients with and 70 without diabetes. At admission we measured serum calcium (Ca), phosphate (P), sodium (Na), potassium (K), creatinine (Cr), alkaline phosphatase total activity (AP), albumin adjusted serum calcium (Caalb adj), 25 hydroxy-vitamin D (25OHD), PTH, and 24-h urinary Na/Cr (uNa/Cr), K/Cr (uK/Cr), Ca/Cr (uCa/Cr), P/Cr (uP/Cr) ratios, and calcium excretion (Ca ex).

RESULTS

25OHD levels of patients with and without diabetes did not significantly differ. In patients without diabetes recruited from November to April, 25OHD levels were significantly lower than those from May to October, whilst patients with diabetes did not show a significant seasonal variation. PTH had opposite non-significant seasonal variations, and negatively correlated with 25OHD in both groups of patients. This correlation was lost after adjusting for age and body mass index in patients with diabetes. These inpatients had higher serum P and lower uP/Cr, according to lower PTH. Their serum glucose negatively correlated with uCa/Cr and Ca ex, contrary to inpatients with other diseases. Instead, uCa/Cr and Ca ex correlated with uNa/Cr only in patients without diabetes.

CONCLUSIONS

Inpatients with diabetes did differ from those with other disorders for vitamin D status and calcium-phosphate homeostatic mechanism.

[Guidelines on prevention and treatment of vitamin D deficiency. Italian Society for Osteoporosis, Mineral Metabolism and Bone Diseases (SIOMMMS)]

The Italian Society for Osteoporosis, Mineral Metabolism and Bone Diseases (SIOMMMS) has elaborated the following guidelines about the definition, prevention and treatment of inadequate vitamin D status. The highlights are presented here. Daily vitamin D allowance ranges from 1,500 IU (healthy adults) to 2,300 IU (elderly with low calcium intake). Since the average Italian diet includes around 300 IU/day, subjects with no effective sun exposure should be supplemented with 1,200-2,000 IU vitamin D per day. The serum 25-hydroxy-vitamin D [25(OH)D] levels represents the most accurate way to assess vitamin D repletion, even though there are still no standardized assay methods. Conditions of “deficiency” and “insufficiency” are defined by the following ranges of 25(OH)D levels: less than 20 ng/ml and 20-30 ng/ml, respectively. In Italy, approximately 50% of young healthy subjects have vitamin D insufficiency during the winter months. The prevalence of deficiency increases with ageing, affecting almost all elderly subjects not on vitamin D supplements. When a condition of deficiency has been identified, a cumulative dose of 300,000-1,000,000 IU, over 1-4 weeks is recommended. In subjects recently treated for deficiency-insufficiency, a maintenance dose of 800-2,000 IU/day (or weekly equivalent) is recommended. In patients on daily doses over 1,000 IU, 25(OH)D levels should be checked regularly (e.g. once every two years). The highest tolerated daily dose has been identified as 4,000 IU/day. Vitamin D supplementation should be carefully monitored in patients at higher risk of vitamin D intoxication (granulomatosis) or with primary hyperparathyroidism. In pregnant women, vitamin D supplements should be given as in non-pregnant women, but bolus administration (i.e.: single dose >25,000 IU) should be avoided.

Carboxyl-terminal parathyroid hormone fragments: biologic effects

Carboxyl-terminal PTH fragments (C-PTH), are generated by both direct secretion from parathyroids in relation to serum calcium levels and catabolism of PTH operated by the Kupffer cells in the liver. These molecular fragments have been till recently regarded as inert byproducts of PTH metabolism, since they do not interact with the PTH/PTH-related peptide (rP) receptor, which mediates the classical hormone actions. Current findings instead indicate that C-PTH would interact with a putative C-PTH receptor. This way, C-PTH seem to exert specific effects on calcium homeostasis and bone metabolism, opposite to those of the synthetic agonist of PTH/PTHrP receptor (i.e. PTH 1-34). In vitro and in vivo data actually indicate that C-PTH, by interacting with specific receptors, could have an anti-calcemic action, as well as a pro-apoptotic effect on both osteocytes and osteoclasts. This in turn could result in a reduced activity of the latter cells, with a consequent inhibition of bone resorption.

Sporadic and hereditary primary hyperparathyroidism

Primary hyperparathyroidism (PHPT) is a common endocrine disorder, particularly frequent in post-menopausal women. It is characterized by hypercalcemia with inappropriately high spontaneous plasma PTH. Singlegland adenoma is the most common cause (75- 85%). PHPT is usually a sporadic disease but in approximately <5% of cases, a familial hyperparathyroid syndrome is diagnosed. Familial hyperparathyroidism is a clinically and genetically heterogeneous group of disorders including: multiple endocrine neoplasia (MEN) type 1, MEN type 2A, MEN4, benign familial hypocalciuric hypercalcemia, neonatal severe hyperparathyroidism, hyperparathyroidism-jaw tumor syndrome, and familial isolated hyperparathyroidism. These syndromes show mendelian inheritance patterns and the main genes for most of them have been defined. The classic form of PHPT, which presents with hypercalcemia, kidney stones, and bone disease, is no longer common. Currently, there is an increasing interest in the subtle manifestations of PHPT, particularly the cardiovascular and neuropsychiatric manifestations. Parathyroidectomy is the definitive cure for PHPT even though patients with the asymptomatic form of the disease can be followed conservatively.

Sun exposure questionnaire predicts circulating 25-hydroxyvitamin D concentrations in Caucasian hospital workers in southern Italy

INTRODUCTION

Recent sun exposure should correlate with circulating 25-hydroxyvitamin D [25(OH)D] due to ultraviolet B (UVB)-catalyzed cutaneous synthesis of vitamin D.

METHODS

A Sun Exposure Score was calculated for healthy adults using a recall questionnaire assessing daily Time in Sun (<5 min, 5-30 min, >30 min) and Skin Exposure (face/hands; face/hands and arms; face/hands and legs; and "bathing suit") for 1 week in each of the winter and summer (n=47 and 23, respectively; n=18 participated in both). Concentrations of 25(OH)D were measured by DiaSorin RIA on end-of-week sera.

RESULTS

Mean serum 25(OH)D was higher in summer than winter (58.6+/-16.5 nmol/L vs. 38.8+/-29.0 nmol/L, respectively, P=0.003 unpaired). The calculated Sun Exposure Score correlated strongly with serum 25(OH)D during summer (Spearman's rho=0.59, P=0.003); based on the Pearson coefficient of determination, summer Sun Exposure Score explained 38% of the variability in summer serum 25(OH)D. The Sun Exposure Score did not correlate with 25(OH)D in the winter (rho=0.19, P=0.210). The summer correlation was largely explained by the Time in Sun (rho=0.58, P=0.004) rather than area of Skin Exposed (rho=0.10, P=0.660). Although there was a correlation between winter and summer Sun Exposure Scores (rho=0.63, P=0.005), there was no summer vs. winter correlation in serum 25(OH)D (rho=0.08, P=0.76).

CONCLUSION

This simple 1-week sun exposure recall questionnaire predicted summer serum 25(OH)D concentrations, accounting for 38% of the variability in 25(OH)D among healthy Italian adults.

Relationship between bone metabolism and adipogenesis

Several findings indicate that adipose tissue and bone have a complex reciprocal relationship. The two cells lineages share a common progenitor, and adipocyte endocrine activity may influence bone metabolism. Recent evidence from animal models suggests that bone cells may contribute regulating energy metabolism.

Skeletal turnover, bone mineral density, and fractures in male chronic abusers of alcohol

BACKGROUND

Chronic alcohol abuse is a risk factor for osteoporosis and fractures, whose pathogenesis is still unclear. We investigated the influence of alcoholism and other risk factors on calcium and skeletal metabolism, bone mineral density (BMD), and fractures.

MATERIALS AND METHODS

In 51 chronic male alcoholics without liver failure and 31 healthy controls, serum total and ionised calcium, phosphate, creatinine, 25-hydroxy vitamin D (25OHD), PTH, total (ALP) and bone-specific (BALP) alkaline phosphatase, osteocalcin (BGP), carboxy-terminal telopeptide of type I collagen (beta-CTx), osteoprotegerin (OPG) and receptor activator of nuclear factor kappa B ligand (RANKL) were assessed. In patients only, we also measured serum testosterone, 17-beta estradiol, LH, and IGF-I. BMD was measured by dual energy x-ray absorptiometry at lumbar spine (LS-) and femur [neck (FN-) and total hip (TF-)]. Vertebral fractures were identified by a semiquantitative method on thoraco-lumbar spine x-ray, non-vertebral fractures (as life-style factors) by history.

RESULTS

Alcoholics were leaner, had significantly higher ALP and BALP, and lower BGP and 25OHD levels than controls. No significant difference in other calcium and bone metabolism parameters was found. OPG/RANKL ratio was significantly higher in alcoholics. Beta-CTx negatively correlated with abuse duration. OPG positively correlated with daily alcohol assumption and with indexes of liver cytolysis. Though LS-, FN- and TF-BMD of alcoholics and controls did not significantly differ, patients had a much higher prevalence of vertebral fractures. The same was found considering both vertebral and non-vertebral fractures.

CONCLUSIONS

Ethanol-induced skeletal damage seems mainly dependent on negative effects on bone formation. Lifestyle factors and traumas likely contribute to the high fracture incidence of alcohol abusers, independently of BMD.

Role of thoracic ultrasound in the assessment of pleural and pulmonary diseases

Although numerous studies have been conducted on the use of ultrasonography (US) for the examination of thoracic structures, this procedure is not as widely accepted as abdominal US. The newer portable scanners can be used at the bedside to detect pleural malignancies and effusions, as well as peripheral lung nodules of the lung, even in seriously ill patients. Focal thickening of the pleura can be easily detected with US and further investigated with a US-guided biopsy. US guidance can also be used during percutaneous drainage of pleural effusion or transthoracic biopsy of peripheral lung lesions, thus reducing the incidence of procedure-related pneumothorax to almost zero. We review the current literature on thoracic US and present our clinical experience with the technique in large groups of patients with pleural and peripheral lung diseases.

Skeletal involvement in adult patients with endogenous hypercortisolism

Overt endogenous glucocorticoid excess is a well-recognized cause of bone loss and osteoporotic fractures. Cortisol excess inhibits bone formation, increases bone resorption, impairs calcium absorption from the gut, and affects the secretion of several hormones (in particular gonadotropins and GH), cytokines, and growth factors, influencing bone metabolism. The glucocorticoid excess mainly affects trabecular bone, leading to vertebral fractures in up to 70% of patients. Osteoporotic fractures may be the presenting symptom of an otherwise silent glucocorticoid excess and can precede the diagnosis of hypercortisolism by up to 2 yr. The removal of glucocorticoid excess leads to a recovery of bone mass which is, however, often incomplete and delayed, although it reduces the risk of osteoporotic fractures. Bisphosphonate therapy has been suggested to be useful in maintaining bone mass in these patients. Subclinical hypercortisolism, a condition of impaired hypothalamic- adrenal-axis homeostasis without the classical signs and symptoms of glucocorticoid excess, is a recently defined entity, which has been shown to be associated to increased bone resorption, bone loss, and high prevalence of vertebral fractures regardless of gonadal status. However, data about the effect of this subtle glucocorticoid excess on bone are still scarce and conflicting. Moreover, it is not yet known whether removing the cause of subclinical hypercortisolism leads to a recovery of bone mass and reduces the risk of osteoporotic fractures. Finally, recent data suggest that subclinical hypercortisolism is a common and underrated finding in patients with established osteoporosis. In summary, it is crucial to evaluate the risk of osteoporosis and fractures in patients with glucocorticoid excess; on the other hand, it also seems advisable to screen for glucocorticoid excess patients with osteoporotic fractures without known secondary causes of osteoporosis.

HIV-1 Integrase–DNA Interactions Investigated by Molecular Modelling

HIV-1 integrase is the viral enzyme responsible for the insertion of the viral DNA into the host cell chromosome. This process occurs through two distinct biochemical reactions: the 3′-processing of the viral DNA and the transesterification reaction. Because experimental structural information on the reaction intermediate is not available, several molecular models have been developed. Unfortunately, none of the models of the enzyme–substrate complex is fully consistent with the available molecular biological data. We have constructed a new theoretical model based on mutagenesis experiments and cross-linking data, using a relatively accurate computational setup. The structural features of the model along with its limitations are discussed here.

[Primary hyperparathyroidism]

Primary hyperparathyroidism (PHPT) is characterized by excessive PTH secretion in respect to calcium homeostasis needs, due to parathyroid adenoma (80% of cases), hyperplasia (15-20%), or carcinoma (1-2%). In familial forms of PHPT, several mutations have an established role: menin gene for MEN type 1, RET for MEN type 2a, calcium-sensing receptor gene for familial hypocalciuric hypercalcemia, parafibromin gene for PHPT-jaw tumour and carcinoma. Etiology of sporadic adenomas (80% of PHPT cases) is less defined, being most commonly found a mutation of menin gene or activation of PRAD1 oncogene. In recent years, the classical features of the disease became less common. Typically, bone involvement is now represented by a reduced bone mass at skeletal sites more rich in cortical tissue. Prominently trabecular skeletal sites are relatively spared, because of the anabolic effects of a slight PTH excess on trabecular tissue. PHPT patients may have increased fracture risk, though it is not clear why bone damage is more severe in a subgroup of patients. Clinical features of hypercalcemia may be fatigue, anorexia, thirst, and polyuria. Vague neurological and psychiatric symptoms, such as weakness, anxiety, depression, paresthesias, and muscular cramps may ameliorate after parathyroidectomy. Recent reports indicate increased cardiovascular mortality in PHPT patients. Diagnosis is based on the detection of hypercalcemia, together with inappropriately high serum PTH levels. Preoperative localization of the diseased glands is mandatory in persistent or recurrent PHPT, as like as when minimally invasive surgery is planned. High resolution ultrasonography and SPECT double-phase 99m Tc-sestamibi scintigraphy are the most commonly employed techniques. Intraoperatory PTH assay may confirm successful surgery when serum concentrations decrease more than 50%. Surgical therapy is indicated in patients with renal or skeletal complications, such as in those with previous parathyrotoxic crisis. Many surgeons in recent years adopted minimally invasive parathyroidectomy. Medical treatment is an option for patients unwilling or unfitted for surgery because of severe concomitant diseases. Employed therapy includes estrogens, SERMs, bisphosphonates and calcimimetics.

Prevalence of hypercalcemia in hospitalised patients: effects of "correction" for serum albumin values

Hypercalcemia is ideally detected by the measurement of serum ionised calcium. Because this is not widely available, in common clinical practice "albumin-corrected" calcium values are often utilized. Our study investigated whether the method used to measure serum albumin concentration may significantly interfere in the derived serum calcium values and, consequently, in the identification of hypercalcemic patients. In 170 consecutive patients admitted to our Department of Internal Medicine we measured serum total calcium, total protein, and albumin by colorimetric method; albumin concentration was also derived by electrophoresis assessment. After correcting serum calcium for colorimetrically (CA) and electrophoretically (EA) measured albumin values, the detected frequencies of hypercalcemia were compared, utilizing different cut-off limits (i.e. 11.0, 10.4 and 10.2 mg/dl). In our patients, the CA values were significantly lower than EA levels. As a consequence, EA-corrected calcium, as well as total calcium concentration were significantly lower than CA-corrected values. This may also account for the very different prevalence of hypercalcemic patients identified by serum total, EA-corrected and CA-corrected calcium values. Our data therefore indicate the importance of the method of albumin measurement in the determination of "corrected" calcium concentration.

Dehydroepiandrosterone sulfate and bone resorption rates as reflected by serum levels of C-terminal telopeptide of type I collagen: a study in healthy men

Sex steroid hormones contribute to the physiological regulation of bone turnover in males. To address this issue, we investigated serum estradiol (E2), total testosterone (T), and DHEAS concentrations, along with serum levels of carboxy-terminal telopeptide of type I collagen (sCTx), in a sample of 76 healthy men aged 23 to 87. The concentration of sCTx declined with age. Both T and DHEAS, at variance with E2, showed a significant age-related decline. T, DHEAS and sCTx significantly (p<0.01) correlated with each other. DHEAS and T were significantly associated after correcting for age (r=0.35, p=0.002) or body mass index (r=0.65, p<0.0001). DHEAS, but not T, significantly correlated with sCTx after correcting for age (r=0.26, p=0.026, and r=0.20, p=0.08, respectively). Stepwise multiple regression analysis showed that only DHEAS (but not T or E2) was a significant independent predictor of sCTx (p=0.0001). Our results show that adrenal androgens play a crucial role in regulating bone resorption in aging men.

Platelet activation in patients with colorectal cancer

Aspirin may reduce the risk of colorectal neoplasia at doses similar to those recommended for the prevention of cardiovascular disease. Thus, we aimed to address whether enhanced platelet activation, as assessed by the measurement of the urinary excretion of 11-dehydro-TXB(2) (a major enzymatic metabolite of TXB(2)), occurs in patients with colorectal cancer. In 10 patients with colorectal cancer, the urinary excretion of 11-dehydro-TXB(2) was significantly higher than in 10 controls, matched for sex, age and cardiovascular risk factors [1001(205-5571) versus 409(113-984) pg/mg creatinine, respectively, median (range), P<0.05]. The administration of aspirin 50 mg daily for 5 consecutive days to colorectal cancer patients caused a cumulative inhibition of platelet cyclooxygenase (COX)-1 activity either ex vivo, as assessed by the measurement of serum TXB(2) levels, or in vivo, as assessed by urinary 11-dehydro-TXB(2) excretion. In conclusion, enhanced platelet activation occurs in colorectal cancer patients. Permanent inactivation of platelet COX-1 by low-dose aspirin might restore anti-tumor reactivity.

[Case report: Acro-necrosis of the upper limbs caused by gemcitabine therapy]

INTRODUCTION

Even if infrequent, a digital necrosis after chemotherapy can occur in cancer patients. The gemcitabine is generally well tolerate; the cutaneous toxic ulcerations only in 0.3% of the cases induces the suspension of the treatment.

CLINICAL CASE

A 70 year old patient, female, with a bladder cancer, after a trans-urethral resection, is submitted to adjuvant chemotherapy with Gemcitabine 1700 mg (total dose/die), with administration in the days 1st and 8th, while in the 15th day was not effected because, to distance of 3-4 days from the second administration, appear paresthesies of the fingers of the hands, together with Raynaud type phenomenon, 38-39 degrees C intermittent fever, digital necrosis and fingertips gangrene. Laboratory: (Normal): RF; AutoAb: AMA, ASMA, APCA, anti-DNA; ENA; lupus anti-coagulant; Ab-anti-cardiolipin; C3-C4, CIC; homocysteine, anti-thrombin, protein C, protein S, mutation of the factor V of Leiden, plasminogen, alfa 2-antiplasmin. (Altered): Auto-antibody: ANA (on Hep-2): positive (title 1/160, speckled pattern), cryoglobulin positive, ESR 29; Instrumental examinations: Superior Limbs Angiograpy: Occlusion of the digital arteries proper of 2nd, 3rd and 4th finger of the hands. Electromyography Inferior Arts: normal. Superior Arts: bilateral suffering of the median nerve at the carpal tunnel. Biopsy of the hand cutis: Hyperkeratosis, acanthosis and papillomatosis of the skin. Arterial vases with signs of endothelioangiitis and aspecific inflammation.

CONCLUSIONS

Even if acronecrosis of the superior limbs is a rare effect of the gemcitabine, we would recommend particular caution in the administration of this drug in patient with known autoimmune disorders.

Global skeletal uptake of 99mTc-methylene diphosphonate (GSU) in patients affected by endocrine diseases: comparison with biochemical markers of bone turnover

This study aimed to clinically validate the global skeletal uptake (GSU) of (99m)Tc-methylene diphosphonate ((99m)Tc-MDP), and to compare it with a marker of bone formation (i.e. serum osteocalcin or OC) and an index of bone resorption (i.e. urinary deoxypyridinoline or U-DPD) in different endocrine disorders affecting the skeleton. We studied 29 female patients with thyrotoxicosis (TT), 27 with primary hyperparathyroidism (PHPT), 16 with acromegaly (AC), 15 with Cushing's syndrome (CS), and altogether 110 healthy women matched for age, BMI and menstrual status. In all subjects total body digital scan images (TBDS) were acquired at 5 min and at 4 h after the administration of (99m)Tc-MDP; the whole body retention (WBR) of the tracer was measured by counting two identical sets of rectangular ROIs, and GSU was subsequently calculated by drawing an irregular ROI on 4 h TBDS images. Serum OC was assessed by IRMA and urinary DPD by fluorometric detection after reverse phase high pressure chromatography. In TT patients GSU (40.0 +/- 5.1 vs 36.5 +/- 4.8%), OC (19.1 +/- 11.8 vs 7.1 +/- 2.9 microg/l) and U-DPD (62.4 +/- 42.7 vs 19.5 +/- 5.3 pmol/pmol) were significantly ( p<0.01) higher than in controls. PHPT patients showed GSU (47.2 +/- 6.6 vs 37.8 +/- 5.3%), OC (38.6 +/- 40.9 vs 8.2 +/- 2.5 microg/l), and U-DPD (55.0 +/- 51.3 vs 21.9 +/- 6.1 pmol/pmol) values significantly ( p<0.001) higher than controls. In CS patients, GSU (39.6 +/- 6.4 vs 32.7 +/- 3.5%; p<0.01) and U-DPD (22.8 +/- 8.4 vs 16.5 +/- 2.7 pmol/pmol; p<0.05) were higher, whereas OC (3.6 +/- 2.4 vs 5.2 +/- 1.9 mg/l; p<0,05) was lower than in controls. In AC patients, GSU (34.9 +/- 5.3 vs 35.2 +/- 3.4%) did not differ significantly from controls, whereas OC (16.8 +/- 8.8 vs 6.9 +/- 2.9 microg/l; p<0.001) and U-DPD (30.9 +/- 13.6 vs 21.0 +/- 5.7 pmol/pmol; p<0.01) were higher. Stepwise multivariate linear regression analysis was performed with disease activity, creatinine clearance, age, and years since menopause as predictor variables and GSU or OC or U-DPD as dependent variables. The significant partial regression coefficients ( r) were: in TT, free triiodothyronine (fT3) with GSU ( r = 0.37; p<0.005), Ln OC ( r = 0.30; p = NS), Ln U-DPD ( r = 0.76; p<0.0001), respectively; in PHPT, PTH with GSU ( r = 0.74; p<0.001), Ln OC ( r = 0.50; p<0.05), Ln U-DPD ( r = 0.64; p<0.001); in CS Ln urinary free cortisol with OC ( r = -0.68; p<0.001) and U-DPD ( r = 0.66; p<0.05). Our data suggest that GSU could represent a valuable clinical tool for evaluating bone turnover rate in PHPT, CS, TT but not in AC. The behavior of GSU and OC and U-DPD is non-uniform in disorders characterized by a marked uncoupling between bone formation and resorption.

Gender differences in serum markers of bone resorption in healthy subjects and patients with disorders affecting bone

To assess how two different serum markers of bone resorption may reflect changes in bone turnover, we compared age- and sex-related changes in serum C-terminal telopeptide of type I collagen (betaCTx) and tartrate-resistant acid phosphatase activity (TRAP) in 136 healthy men and 184 normal women. Serum levels of the two markers were also assessed in several groups of patients of both sexes presenting with the most common metabolic and endocrine bone diseases: established osteoporosis (n = 77), primary hyperparathyroidism (n = 44), glucocorticoid excess (n = 17), chronic renal failure (n = 39), active Paget's disease of bone (n = 5), humoral hypercalcemia of malignancy (n = 3), osteomalacia (n = 3), hyperthyroidism (n = 10), post-surgical hypoparathyroidism (n = 10), acromegaly (active disease, n = 8) and Cushing's syndrome (n = 10). In men the regression of betaCTx with age showed an initial decrease in bone resorption followed by an increase thereafter, starting from the sixth decade of life. No age-related change in serum TRAP activity was observed. In women, by contrast, a slight but significant linear correlation of both serum betaCTx and TRAP with age (r = 0.223, p<0.003 and r = 0.333, p<0.0001, respectively) was found, the two markers being positively correlated (r = 0.238, p<0.002). In each class of patients the mean Z-scores of betaCTx were significantly higher than those of TRAP activity. Moreover, compared with normal subjects, serum betaCTx seems to be characterized by a superior sensitivity relative to TRAP measurement, at least in the disorders studied.

Longitudinal evaluation of vitamin D status in healthy subjects from southern Italy: seasonal and gender differences

Vitamin D status is currently considered among the relevant determinants of skeletal integrity. Since vitamin D levels present seasonal variations, we longitudinally studied young healthy men and women in order to investigate the related physiologic modifications of both calcium homeostasis and bone remodeling. Thirty-two men (mean age 39.4 +/- 7.8 years) and 58 premenopausal women (aged 36.9 +/- 6.4 years) from southern Italy were studied. In all subjects the following parameters were measured both in winter and in summer: serum calcium, phosphorus, creatinine, total alkaline phosphatase activity, 25-hydroxyvitamin D (25OHD), parathyroid hormone (PTH), osteocalcin (BGP), together with urinary calcium (Ca/Cr), total pyridinoline (Pyr/Cr) and deoxypyridinoline (d-Pyr/Cr), corrected for creatinine excretion. In both sexes 25OHD levels were significantly higher in summer, while PTH values were lower, than in winter. The prevalence of hypovitaminosis D, defined by concentrations of 25OHD lower than 30 nmol/l, was 17.8% in winter and 2.2% in summer in the whole sample, while it was 27.8% and 3.4%, respectively, among female subjects. Indeed male subjects did not display hypovitaminosis D, having throughout the year significantly higher calcium and 25OHD levels together with lower PTH values, than the women. Moreover, alkaline phosphatase total activity was more elevated in men both in winter and in summer. In women, during winter, bone remodeling markers levels were higher while urinary calcium levels were lower than in summer. In the whole sample serum 25OHD correlated positively with serum calcium and inversely with PTH. The seasonal percentage variations in PTH were inversely correlated with those of Ca/Cr. Our results show a relatively high prevalence of subclinical vitamin D deficiency among young healthy women from southern Italy. Significant gender-specific differences have been demonstrated in both calcium homeostasis and skeletal remodeling indexes; the seasonal fluctuations in the vitamin D-PTH axis are accompanied by cyclical variations of bone turnover rate, which were more pronounced in women.

Bone loss rate in adrenal incidentalomas: a longitudinal study

Although by definition patients with adrenal incidentalomas (AI) do not have evident clinical syndromes, they may frequently suffer from subclinical hypercortisolism (SH). This is of some importance because of evidence that SH may lead to clinical complications, including bone loss. Thus, the understanding of bone involvement due to SH may be extremely important in the management of AI. Unfortunately, the available data on bone mineral density (BMD) in AI patients come from cross-sectional studies, which, to further complicate our understanding, are also conflicting, probably due to a different selection of patients and/or the variability in cortisol secretion (CS) often described in AI. To gain further insight about this topic, we performed a longitudinal study evaluating the rate of spinal and femoral bone loss levels in 24 females with AI. AI subjects were subdivided in two groups on the basis of the median of urinary cortisol secretion (UFC): group I (n = 12; UFC, <140.4 nmol/24 h) and group II (n = 12; UFC, >140.4 nmol/24 h). Spinal BMD was measured by both single energy quantitative computed tomography (L1-L4) and dual energy x-ray absorptiometry (DXA; L2-L4), and femoral BMD was determined by DXA. Bone loss rate was expressed as the change in z-score per yr. The spinal bone loss rate was higher (P < 0.005) in group II than in group I when measured by both quantitative computed tomography (-0.19 +/- 0.14 vs. 0.00 +/- 0.15) and DXA (-0.19 +/- 0.17 vs. 0.00 +/- 0.11). Moreover, CS and spinal bone loss rate were significantly correlated when patients were considered together. In conclusion, our data show that 1) AI patients with higher CS have increased lumbar trabecular bone loss rate than those with lower CS; and 2) the degree of spinal bone loss rate is related to the degree of CS. Thus, lumbar spine (LS) BMD has to be evaluated for well balanced decision-making on the treatment of choice for AI female patients.

Short-term effects of surgery in post-menopausal patients with primary hyperparathyroidism and normal bone turnover

The most common clinical presentation of primary hyperparathyroidism (PHPT) is nowadays characterized by a slight skeletal involvement. We studied 5 consecutive female patients with PHPT presenting with bone turnover marker levels within the reference range of our Center and whose bone mineral density values were above the usual fracture risk threshold. In each patient we measured, both in basal conditions and daily, for the first 5 days after surgery, the following indexes: serum total (T-ALP) and bone-specific (B-ALP) alkaline phosphatase activity, osteocalcin (BGP, by two different assays), together with the 24-hour urinary excretions of total pyridinoline (Pyr/Cr) and deoxypyridinoline (DPyr/Cr), free deoxypyridinoline (FD-Pyr/Cr), cross-linked N-telopeptide of type I collagen (NTx/Cr), and type I C-telopeptide (CTx/Cr). The markers of both bone formation and resorption significantly decreased after surgery (p<0.001 by multiple ANOVA). Individual post-surgical markers changes were all significant but T-ALP and FD-Pyr, the most pronounced percent reductions being shown by NTx and CTx. The time-course of such variations substantially differed among the various indexes. These results show that bone formation and resorption markers are up-regulated also in PHPT patients with mild skeletal involvement; acute removal of parathyroid hormone excess differently affected the markers of bone turnover in terms of both entity and time-course.

Different patterns of global and regional skeletal uptake of 99mTc-methylene diphosphonate with age: relevance to the pathogenesis of bone loss

Bone turnover changes with age have been shown by both histomorphometric and scintimetric methods; fewer studies have been performed on the regional differences of bone remodeling in the aging skeleton. To noninvasively investigate this issue, we evaluated the age-related patterns of global and regional bone uptake of 99mTc-methylene diphosphonate (MDP) in a large sample of healthy women.

METHODS

In a group of 84 healthy women (33 pre- and 51 postmenopausal), the uptake of 99mTcMDP was semiquantitatively measured in 5 regions of interest. Total-body digital scans (TBDSs) were acquired at 5 min and at 4 h. Five regions of interest were drawn on the skeleton as a whole, on the lumbar spine, on the iliac wing, on the femoral neck, and on the femoral diaphysis of the 4-h TBDS. Regional skeletal uptake of the lumbar spine (LS-RSU), of the iliac wing (IL-RSU), of the femoral neck (FN-RSU), and of the femoral diaphysis (FD-RSU) was calculated as percentage injected dose retained in these skeletal segments at 4 h.

RESULTS

As expected, in postmenopausal women the global skeletal uptake (GSU) values were higher than those in premenopausal women (40.7 +/- 5.9 percentage injected dose [%ID] versus 35.1 +/- 4.2 %ID; P < 0.0001). GSU correlated positively with age (r = 0.70; P < 0.001), but the addition of years since menopause to the regression model did not ameliorate the regression. On the other hand, LS-RSU (r = -0.55; P < 0.0001), IL-RSU (r = -0.45; P < 0.0001), and FN-RSU (r = -0.22; P < 0.005) decreased significantly, whereas FD-RSU increased significantly (r = 0.39; P < 0.001) with age; the same regressions were not influenced significantly by the addition of menopausal duration to the regression model. The strongest correlation among the different RSUs was that found between LS-RSU and IL-RSU (r = 0.63; P < 0.001). Moreover, the linear regression coefficients of the various RSUs with age were all significantly different from each other (P < 0.001).

CONCLUSION

Our data show that the GSU of 99mTc-MDP increases with age, whereas different skeletal segments display a variable degree of turnover activation at different ages. This could ultimately induce the different rates of bone loss of different skeletal segments at various ages and, consequently, their variable propensity to fracture.

Phalangeal US velocity discriminates between normal and vertebrally fractured subjects

The purpose of this study was to evaluate the diagnostic sensitivity of phalangeal bone ultrasound velocity of the hand in the diagnosis of osteoporosis and to compare this technique to bone mineral density (BMD) measurement at the lumbar spine assessed by dual X-ray absorptiometry (DXA) and quantitative computed tomography (QCT). We investigated US velocity at the distal metaphysis of the proximal phalanx and spinal BMD in 101 women. Fifty-nine were healthy (mean age 50 +/- 11.6 years) and 42 were osteoporotic (mean age 65 +/- 6.6 years) with documented vertebral fractures. In the healthy population the relation with age was, respectively, r = -0.73 (p < 0. 0001) for quantitative US (QUS), r = -0.74 (p < 0.0001) for QCT and r = -0.48 (p < 0.01) for DXA. Both US and DXA were correlated with QCT: r = 0.74 and r = 0.77 (p < 0.0001), respectively. Correlation of QUS and DXA was r = 0.56 (p < 0.0001). Phalangeal US velocity and spinal BMD (QCT and DXA) values discriminate healthy from osteoporotic women. Age-adjusted logistic regression analysis of the data showed standardized odds ratios (OR) for vertebral fracture to be similar for US and DXA (OR = 1.8 and 1.5, respectively) and stronger for QCT (OR = 2.9). Phalangeal US velocity reflects age-related bone loss and differentiates between healthy and osteoporotic subjects.

Altered bone mass and turnover in female patients with adrenal incidentaloma: the effect of subclinical hypercortisolism

The strategy of treatment for patients with adrenal incidentalomas (AI) may depend upon the presence of hormonal hypersecretion. Although alterations of bone turnover have been recently reported, data on bone mineral density (BMD) are not available in AI patients. We evaluated bone turnover and BMD in 32 female AI patients and 64 matched controls. Spinal and femoral BMD were similar in patients and controls. Serum bone GLA protein (6.8+/-3.5 vs. 8.8+/-3.2 ng/mL; P<0.005) and PTH (48.8+/-15.1 vs. 37.2+/-10.9 pg/mL; P<0.0001) were different in patients and controls. Patients were then subdivided into 2 groups: with (n = 8; group A) or without (n = 24; group B) subclinical hypercortisolism. PTH was higher (P<0.05) in group A than in group B and in both groups than in controls (57.1+/-13.6, 46.0+/-14.8, and 37.2+/-10.9 pg/mL, respectively), and bone GLA protein was lower in group A than in group B and controls (3.8+/-2.3, 7.5+/-3.1, and 8.8+/-3.2 ng/mL, respectively; P<0.05). Serum type I cross-linked C telopeptide and fasting urinary deoxypyridinoline/ creatinine were not different in the three groups. BMD at each site was lower (P<0.05) in group A than in group B and controls. Bone mass and metabolism are altered in AI patients with subclinical hypercortisolism and should be taken into account, therefore, when addressing the treatment of choice for these patients.

Clinical validation of a new immunoradiometric assay for intact human osteocalcin

The purpose of this study was to estimate clinical validity of a new available immunoradiometric assay for circulating intact human BGP (N-tact Osteo SP) by measuring this protein in a large number of normal subjects and patients with the most common metabolic bone diseases. One hundred normal subjects were studied in order to obtain our normal ranges (4.9 +/- 1.7 ng/ml). The mean values found in 28 patients with primary hyperparathyroidism (17.5 +/- 22.8 ng/ml, P < 0.001), 15 glucocorticoid-treated patients (1.9 +/- 1.5, P < 0. 001), 10 patients with hypoparathyroidism (1.5 +/- 0.7, P < 0.001), 9 with hyperthyroidism (8.3 +/- 3.8, P < 0.001), 8 with skeletal metastases (7.2 +/- 2.3, P < 0.001), and 4 with humoral hypercalcemia of malignancy (2.42 +/- 1.91, P < 0.005) were significantly different from mean values found in normal subjects. Mean decrease of serum osteocalcin T-score values was significantly greater when evaluated by N-tact Osteo SP assay in 15 steroid-treated patients (-1.4 +/- 1.0) and 19 primary hyperparathyroid (PHPT) patients (3.6 +/- 1.9), compared with the mean values obtained with the Elsa-Osteo assay (-0.67 +/- 1.2, P < 0. 002 and 4.3 +/- 2.8, P < 0.04, respectively). We found significant correlations between the global skeletal uptake of 99mTc-methylendiphosphonate and serum BGP levels assayed by both N-tact Osteo SP (P < 0.01) and Elsa-Ost-Nat assay (P < 0.05). Our results indicate that this new immunoradiometric assay for the intact human osteocalcin has the potential for good discrimination between normal subjects and patients with both low and high bone turnover. Furthermore, our findings emphasize the fact that, in the absence of available standardized commercial assays, one should rely on only one assay because different results are obtained by different assays under different clinical conditions.

Alterations of bone turnover and bone mass at different skeletal sites due to pure glucocorticoid excess: study in eumenorrheic patients with Cushing's syndrome

The aim of the present investigation was to study the effect of glucocorticoid excess on bone mass and turnover not influenced by other diseases known to affect skeleton and/or by different gonadal status and sex. We studied several markers of bone turnover and bone mineral density (BMD) by both quantitative computed tomography (at spine and forearm) and dual x-ray absorptiometry (at spine and three femoral sites) in 18 eugonadal female patients affected by Cushing's syndrome (CS) compared to 24 eugonadal healthy female subjects matched for age and body mass index. In CS patients, serum bone Gla protein, a marker of osteoblastic function, was reduced (3.28 +/- 2.3 vs. 6.47 +/- 2.5; P < 0.01), and bone resorption was increased, as indicated by increased urinary hydroxyproline (36.6 +/- 12 vs. 29.0 +/- 9.1, P < 0.05) and urinary deoxypyridinoline (22.1 +/- 8.0 vs. 16.4 +/- 6.3; P < 0.05). BMD was significantly (P < 0.05 or P < 0.01) reduced at all sites, except cortical forearm, in CS patients compared to controls. By comparing z-scores of reduced BMD in CS patients, spinal trabecular BMD was found to be the most severely affected. Furthermore, disease activity, as measured by urinary free cortisol, was significantly correlated with bone Gla protein (r = -0.57; P < 0.02), urinary hydroxyproline (r = 0.57; P < 0.02), urinary deoxypyridinoline (r = 0.48, P < 0.05), and BMD measured at spine and femur. Our results show that compared to matched control subjects, female eumenorrheic CS patients have reduced osteoblastic function, increased bone resorption, and reduced BMD, and that the severity of these abnormalities is statistically related to the severity of disease activity, as indicated by urinary free cortisol. Moreover, our data suggest a site and tissue specificity of the effect of glucocorticoid excess on bone mass.

Assessment of serum total and bone alkaline phosphatase measurement in clinical practice

The aim of the study was to measure serum levels of the bone-specific isoenzyme of alkaline phosphatase in normal subjects and patients with metabolic bone disease by using an immunoadsorption assay. We studied 140 healthy adults, 122 patients affected by metabolic bone disease and 15 patients with cholestatic liver disease. Mean values of the bone-specific isoenzyme of alkaline phosphatase in healthy men were significantly higher than those found in premenopausal women (17.8 +/- 4.2 U/l vs 15.6 +/- 4.6 U/l, p < 0.02); postmenopausal women had significantly higher levels of bone-specific isoenzyme of alkaline phosphatase (22.6 +/- 6.4 U/l) than premenopausal women (p < 0.0001). After the menopause total alkaline phosphatase increased by 46%, while the increase in bone-specific isoenzyme of alkaline phosphatase was 39%. No significant correlations were found between bone-specific isoenzyme of alkaline phosphatase and either age or years since menopause, in postmenopausal subjects. In patients with bone-specific isoenzyme of alkaline phosphatase above the upper limit of normal, the assay had a sensitivity of 100% only in patients with Paget's disease of bone. In patients with cholestatic liver disease we found no correlation between bone-specific isoenzyme of alkaline phosphatase and either total alkaline phosphatase and gamma-glutamyl transpeptidase, while a positive correlation was found between total alkaline phosphatase and gamma-glutamyl transpeptidase. Our results confirm the role of bone-specific isoenzyme of alkaline phosphatase assay in clinical research; however, its usefulness in clinical practice is unclear once liver involvement has been excluded.

Global skeletal uptake of technetium-99m methylene diphosphonate in female patients receiving suppressive doses of L-thyroxine for differentiated thyroid cancer

This study was carried out in order to investigate the possible detrimental effects on bone of levothyroxine (l-T4) suppressive therapy in female patients who had undergone surgery for differentiated thyroid cancer (DTC). Twenty female (14 premenopausal and 6 postmenopausal) patients receiving l-T4 suppressive therapy for DTC were studied. The sample was selected in such a way as to avoid factors influencing bone metabolism other than l-T4. All patients were monitored by sensitive thyroid-stimulating hormone, free triiodothyronine and free thyroxine assays throughout the follow-up. Nineteen healthy (12 premenopausal and 7 postmenopausal) matched women served as controls. In all subjects bone turnover was evaluated by the measurement of global skeletal uptake of technetium-99m methylene diphosphonate (GSU); bone mineral density (BMD) was measured by quantitative computed tomography at the lumbar spine (LS) and by dual-energy X-ray absorptiometry both at the LS and at three femoral sites: the femoral neck, Ward's triangle and the greater trochanter. No significant difference was found in either GSU or BMD between patients (treated for an average period of 68 months) and controls in the whole sample or in any subgroup. Furthermore, no correlations were found between either GSU or BMD and the duration of therapy, daily doses of l-T4 or results of thyroid function tests. Our data show that carefully monitored l-T4 therapy does not influence skeletal turnover (directly reflected by GSU) or the bone density of the spine and femur.

Skeletal involvement in female acromegalic subjects: the effects of growth hormone excess in amenorrheal and menstruating patients

Bone involvement is a common clinical feature in acromegalic patients, though previous studies gave divergent results possibly because of the different gonadal status of the patients studied. To study the influence of estrogen milieu in these patients, we evaluated 23 acromegalic patients with active disease, subdivided into two groups: menstruating and amenorrheal patients, comparable for duration and activity of disease. Forty-two matched women served as controls. Skeletal involvement was studied by measuring: (a) the main biomarkers of bone turnover: serum alkaline phosphatase total activity (AP), bone GLA protein (BGP), serum carboxy-terminal propeptide of type I collagen (PICP), serum type I cross-linked N-telopeptide (ICTP), and urinary pyridinoline and deoxypyridinoline corrected for creatinine (Pyr/Cr, D-Pyr/Cr) and urinary calcium/creatinine ratio (Ca/Cr); (b) bone mineral density (BMD), as measured by quantitative computed tomography both at lumbar spine and distal radius, and by dual X-ray absorptiometry both at lumbar spine and at three femoral sites (Ward's triangle, femoral neck, and great trochanter). AP, BGP, ICTP, Pyr/Cr, D-Pyr/Cr were significantly higher in patients than in controls, independent of the menstrual pattern. Higher PICP levels were found in the whole group and in menstruating acromegalics when compared with control women; no difference was found in amenorrheal patients, who in turn showed higher urinary Ca/Cr values. When patients were considered all together, BMD at spine, femoral neck, and trochanter was higher than in controls. In contrast, when the gonadal status was taking into account and, menstruating and amenorrheal subjects were considered separately, BMD at spine, but not in other sites, was significantly higher in menstruating patients than in controls. In contrast, no difference of BMD values at any site was observed between amenorrheal patients and controls. The mean BMD Z scores allowed us to detect an unequal involvement of different skeletal sites. Our results show that bone turnover is increased in acromegalic women and suggest that GH anabolic effect on bone is more evident in the presence of estrogens and that different skeletal sites may be affected differently by hormone excess.

Pulmonary lymphangioleiomyoma in a patient with multiple endocrine neoplasia type I

The multiple endocrine neoplasia (M.E.N.) syndromes consist of a group of proliferative disorders that selectively target specific sets of endocrine and soft tissue cells. Here we report a case of lymphangioleiomyoma of the lung in a patient with multiple endocrine neoplasia Type I (M.E.N. I). This is the first time such an association has been reported. In our opinion it could possibly be ascribed to the genetic predisposition to proliferative disorders of patients with M.E.N. syndromes.

Age-related changes in the global skeletal uptake of technetium-99m methylene diphosphonate in healthy women

A short-term evaluation of global skeletal uptake (GSU) of technetium-99m methylene diphosphonate (MDP) was performed in 40 healthy female subjects with a wide age range in order to investigate the clinical performance of the technique and to detect the age-related changes in bone turnover. The results obtained were compared with measurements of the main biochemical markers of skeletal metabolism. We found that GSU increases progressively with age, independently of concomitant changes in renal function; significant correlations with biochemical markers of bone formation were also found. Therefore, the method appears to provide useful information concerning the bone turnover rate, and is also applicable to elderly people owing to its simplicity.

Case report: reversal of decreased bone mass by antibiotic treatment in a patient with Whipple's disease

Whipple's disease is a rare systemic illness, with the main clinical feature being severe malabsorption syndrome. Bone involvement in the disease has rarely been described in previous articles. The authors report a case in which an extensive skeletal evaluation was carried out. Even though osteomalacia is generally considered the most typical metabolic bone disease of malabsorption syndromes, bone biopsy demonstrated that osteoporosis was the prominent histologic feature in this patient. On the basis of serial bone mineral density measurements, antibiotic treatment was able to reverse the initial reduced bone mass.

Temporal relationship between bone loss and increased bone turnover: a longitudinal study following natural menopause

We report the results of a longitudinal study aimed at better defining concomitant changes of both bone mineral density (BMD) and of four independent markers of bone turnover (serum osteocalcin, serum alkaline phosphatase activity, fasting urinary hydroxyproline/creatinine and calcium/creatinine ratio) following natural menopause. The results obtained indicate that, within a relatively short period of time since cessation of gonadal function, conventional markers of bone turnover behave differently. In fact, while the mean values of hydroxyproline/creatinine ratio (felt to be a marker of bone resorption) rise immediately at the first control (19.7 +/- 11.7 months), the bone formation markers gradually increase and, as far as serum osteocalcin levels are concerned, this increment appears to be long-lasting. As a result of these changes, a negative skeletal balance follows, which is documented by the prolonged reduction of bone mineral density during the entire observation period. Mean +/- SD % measured yearly bone loss was -2.83 +/- 2.6. There was a highly significant correlation between initial and final BMD values (r = 0.908, p < 0.001; r2 = 82.5) and a weak inverse correlation (r = -0.298, p < 0.046) between initial serum alkaline phosphatase values and % yearly bone loss. In conclusion, measurement of the biological indices of bone remodelling following natural menopause indicate that the increase in osteogenesis is delayed compared to that of bone resorption; furthermore, in the immediate postmenopausal period, the actual bone mass should be considered the best predictor of future bone mass. The inverse correlation found between % yearly bone loss and serum alkaline phosphatase values seems to emphasize the importance of increased bone turnover as an independent predictor of bone loss.

Circulating levels of insulin-like growth factor binding protein 3 (IGFBP-3) and insulin-like growth factor I (IGF-I) in perimenopausal women

The study investigated possible menopause-related changes in circulating insulin-like growth factor binding protein 3 (IGFBP-3) levels and their relationship with insulin-like growth factor I (IGF-I) plasma levels. Forty-three healthy women, aged 45-55 years, were studied (22 premenopausal and 21 postmenopausal, matched for age and body mass index); in all subjects plasma IGF-I and IGFBP-3 levels were measured by radioimmunoassay. No difference was found between mean IGFBP-3 plasma levels in the two groups studied (premenopausal 3.42 +/- 0.49 v postmenopausal 3.46 +/- 0.58 mg/l), while mean IGF-I levels were significantly lower in postmenopausal as compared with premenopausal women (136.7 +/- 37.86 v 175.7 +/- 51.91 ng/ml, p < 0.02). Multiple regression analysis showed no significant effect of age, body mass index and years since menopause on IGFBP-3 levels; however, considering the IGF-I/IGFBP-3 ratio as a possible parameter of circulating free somatomedin C, an inverse correlation was found with years since menopause (n = 43, r = -0.499, p < 0.001). We conclude that lack of oestrogen induces different effects on circulating IGF-I and IGFBP-3, possibly reflecting a real decrease in IGF-I activity.

Serum ionized calcium, parathyroid hormone and related variables: effect of age and sex

This study was carried out in order to determine interrelationships of age and sex on parameters within the parathyroid endocrine system in healthy men and women. One hundred and fifteen normal subjects (70 females and 45 males) subdivided into three groups aged 25-35, 45-55 and 65-75 years were studied. Female subjects aged between 45 and 55 were further subdivided into two age-matched groups in relation to gonadal functional status. Serum intact parathyroid hormone (PTH) concentrations were measured using a two-site immunoradiometric assay. We found that there was a significant decrease of serum ionized calcium with ageing only in men (r = -0.666, P < 0.001) and a significant increase of serum PTH with age in both men (r = 0.488, P < 0.001) and women (r = 0.279, P < 0.019). A significant inverse correlation was found between serum ionized calcium and PTH in male subjects (r = -0.661, P < 0.001) and in fertile females (r = -0.353, P < 0.037) but not in postmenopausal women or in the entire female population. Furthermore, we found a significant decline of serum phosphate (r = -0.484, P < 0.001) and TmP/GFR (r = -0.492, P < 0.001) with advancing age in men, but not in women. We believe that the decrease of serum ionized calcium, as a likely consequence of the physiological reduction of intestinal calcium absorption, is the pivotal factor responsible for the increased PTH levels we observed with advancing age. The phenomenon is clear in men and in premenopausal women, but is masked in the female sex at menopause by the effects of a shortage of oestrogen on the calcium-phosphorus metabolism. These may also be responsible for the differences observed between the two sexes as far as phosphate metabolism is concerned. In conclusion, this study has, for the first time, taken relationships between serum ionized calcium and PTH, over a wide age range, into consideration. The results obtained show a marked difference of serum ionized calcium values between sexes with ageing, while serum parathyroid hormone levels increase in both men and women. Important differences also exist, as far as phosphate metabolism is concerned, between males and females.

Parathyroid storm: immediate recognition and pathophysiological considerations

A 56-year-old white man was referred for evaluation of severe hypercalcemia following a three-week history of progressive weakness, nausea, and depression. Initial laboratory results showed serum total and ionized calcium (Ca++) values of 5.3 and 2.6 mmol/l, respectively. A short intact PTH assay was immediately performed and an extremely high value was obtained in just 30 min (1315 ng/l, normal values 6.4-70.4). The patient was therefore treated with saline solution and with salmon calcitonin (1200 IU/day, half by continuous i.v. infusion and half by i.m. route) for 10 days. There was a sudden decrease of both Ca++ and intact PTH during the first six days; then there was a trend to reach a steady-state until parathyroidectomy was performed. After withdrawal of calcitonin therapy it was possible to observe a positive uncoupling between bone formation (serum alkaline phosphatase and osteocalcin) and resorption (serum tartrate-resistant acid phosphatase) markers. On day 35 the patient underwent neck exploration, and an enlarged lower left parathyroid gland was removed that on macroscopic examination revealed the presence of a haemorrhagic cyst; microscopic appearance was suggestive of a previous glandular infarction. This is the first time the daily clinical course of a parathyroid crisis has been documented. Furthermore, changes of biomarkers of bone turnover following calcitonin therapy show that high doses of the hormone may cause a prolonged positive uncoupling of the two processes of bone remodeling.

Effect of estrogen deficiency on IGF-I plasma levels: relationship with bone mineral density in perimenopausal women

Bone tissue is a source of growth factors; among them, insulinlike growth factor I (IGF-I) is probably an important local regulator of bone formation. This study has been carried out in order to assess the effects of natural menopause on plasma concentrations of IGF-I in the first 6 years after the cessation of gonadal function independent of age. We also examined the relationship between plasma IGF-I levels and bone mineral density (BMD) measured at the lumbar spine (LS), at the ultradistal radius (UDR), and at the junction of the distal and middle thirds of the radius (MR). Sixty-seven healthy nonobese women, aged 45-55, were studied (premenopausal n = 21; postmenopausal n = 46, from 1 to 6 years since menopause). Plasma IGF-I levels were measured by RIA, after acid-ethanol extraction. BMD of the forearm was measured by dual-photon densitometer and BMD of the LS was assessed by quantitative digital radiography. Mean values of IGF-I plasma levels were significantly reduced in postmenopausal women compared to the premenopausal group. Menopausal duration did not influence IGF-I plasma levels in postmenopausal women. We also found a positive correlation between IGF-I levels and BMD measured at MR both in pre- and postmenopausal women, while a correlation with LS and UDR-BMD was found only in fertile subjects. The results show that IGF-I plasma levels decrease immediately after menopause, since significantly lower levels are reached in the first years. The correlations found between plasma IGF-I levels and BMD suggest a possible role of reduced IGF-I in bone loss at particular skeletal sites.

Serum osteocalcin in metabolic bone diseases: what is its real significance?

This study has been carried out in order to elucidate the clinical significance of serum osteocalcin measurement. The changes of this marker paralleled those of serum total alkaline phosphatase activity (a marker of bone formation) following parathyroidectomy in hyperparathyroid patients with skeletal involvement. Furthermore, the percentage decrease of serum osteocalcin levels in respect to basal values (85 +/- 12), and the percentage decrease of serum alkaline phosphatase activity levels (82 +/- 7) were significantly lower (p < 0.001) in respect to that of the 24-h hydroxyproline/creatinine ratio (42 +/- 14) one week after parathyroid surgery. Instead, changes of serum osteocalcin levels were similar to those of serum free hydroxyproline (considered to be a marker of bone resorption) following acute calcitonin infusion in normal subjects. These results imply that the antibody used in our assay might recognize not only the entire osteocalcin molecule, but also small epitopes released during the process of bone matrix resorption. Alternatively, if we consider serum osteocalcin only as a marker related to some processes of bone formation, the experiment carried out on normal subjects strongly supports the evidence of calcitonin receptors in osteoblastic surfaces.

Trabecular bone mineral density in primary hyperparathyroidism: relationship to clinical presentation and biomarkers of skeletal turnover

This study was carried out in order to investigate the entity of trabecular bone involvement in 62 patients with primary hyperparathyroidism (PHPT). Bone mineral density (BMD) was measured in all patients at the ultradistal radius (UDR) of the non-dominant arm by a dual photon densitometer and also at the lumbar spine (L) in 40 of the patients by means of quantitative dual energy radiography. Mean Z score values of UDR-BMD (-2.4 +/- 0.4) and L-BMD (-3.5 +/- 0.2) in patients with the skeletal variety of the disease (n = 6) were significantly reduced in respect to values of both asymptomatic (n = 31) and kidney stone patients (n = 25). As far as the comparison between the two sites of trabecular bone mass measurement in each hyperparathyroid subgroup of patients was concerned, a significant difference (P < 0.05) was found in patients with skeletal manifestations of the disease. Either serum total alkaline phosphatase activity, or osteocalcin and the 24-h hydroxyproline/creatinine ratio were significantly inversely related to the entity of bone mass evaluated at these two sites. Z score changes following surgery in 14 patients showed a positive trend in 13 of them at L compared to 7 out of 14 at UDR (P < 0.036 by chi square analysis). There was a very good inverse correlation between basal Z score values and the changes following surgery at the L (r = -0.851; P < 0.001) but not at the UDR. Our results demonstrate firstly that, in PHPT skeletal sites with almost similar composition of trabecular bone are differently involved in patients with more severe skeletal damage and that different skeletal sites may be divergently affected by the cessation of parathyroid gland hyperfunction.