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Biomedical subjects

G Aliberti

Publications and source records attributed to G Aliberti.

At least 19 recordsLinked to original sources
PubMed2005

Lymphoscintigraphy with intraoperative gamma probe sentinel node detection: clinical impact in patients with head and neck melanomas.

AIM: The aims of this paper were to evaluate the clinical relevance of lymphoscintigraphy with intraoperative gamma-probe detection in identifying sentinel nodes (SNs) and to study the prognostic value of SN biopsy in head and neck melanoma patients. METHODS: Sixty-one patients had lymphoscintigraphy with intradermal injections of 99mTc-Nanocoll (40 MBq), 24 h before surgery. Tumor-positive SNs patients underwent total lymph node dissection. Postoperative histological examination was performed. Patients were followed up for 1 to 5 years (median 3 years). The tumor relapses and the overall survival were evaluated by means of statistical methods. RESULTS: Lymphoscintigraphy showed lymphatic distribution to more than one basin in 45 patients (74%), in 15 patients one basin was visualized and no basin in 1 patient. In 41 patients the SN was negative for metastases, while in 20 was positive. In a high percentage of patients (30%), metastatic involvement occurred in more than one lymph node basin. During follow-up in the negative SN group, 40 patients remained disease free and 1 relapsed. In the positive SN group, 10 patients remained disease free and 10 relapsed. Recurrence time ranged from 6 to 11 months. The overall survival of the SNs negative group was significantly higher than the positive SN group. CONCLUSIONS: This approach was able to distinguish: a) patients with tumor-negative SNs with a favorable clinical course (98% did not relapse, P<0.001); b) patients with tumor-positive SNs with a high rate of tumor relapse (50%, P<0.001). Therefore SN biopsy may give information about prognosis in head and neck melanoma patients.

Adult↗
PubMed2004

Comparative evaluation of two methods to assay thyroglobulin serum concentrations in patients with differentiated thyroid carcinomas.

AIM: This study was aimed at the comparative assessment of the analytical and clinical performances of 2 tests for thyroglobulin (Tg) assays: the Dynotest Tg-Plus immunoradiometric assay (IRMA), a new method that might be of interest for its claimed superior sensitivity compared to other methods, and the HTGK-2 IRMA, one of the test currently used in clinical routine. METHODS: The study was performed in serum samples from 157 patients with differentiated thyroid carcinoma (DTC). The clinical sensitivity of the test was evaluated in patients with and without thyroid stimulating hormone (TSH) suppression. RESULTS: The lowest detectable Tg concentration values and the within-assay coefficient of variation (CV) were 0.4 and 0.8 microg/L and 5% and 3% for the Dynotest Tg-Plus assay and the HTGK-2 assay, respectively; the between-assay CV was 6% for both assays. The clinical results of the Dynotest Tg-Plus and those of the HTGK-2 kit were similar in both DTC patient populations, either under or off the TSH suppressive treatment. In spite of the manufacturer's statement that the calibrators of both assays had been standardized against the same common reference (standard CRM 457 of the Community Bureau of References), the Dynotest Tg-Plus test underrated by a factor of 0.5 the Tg values measured by means of HTGK-2 IRMA. CONCLUSION: The sensitivity of the Dynotest Tg-Plus IRMA appears to be similar to that of the HTGK-2 assay.

Adolescent↗
PubMed2003

Bone metabolism in ochronotic patients.

We investigated skeletal involvement in five male and two female patients with ochronosis, aged 26-82 years. The main parameters of mineral metabolism, together with biochemical markers of bone resorption (urinary N-telopeptides of type I collagen) and formation (serum bone isoenzyme of alkaline phosphatase and serum osteocalcin) were evaluated. In the same subjects lumbar spine and femoral bone mineral density (BMD) were also measured by dual energy X-ray absorptiometry. All patients but the younger 26-year-old patient had lower than normal bone mass at femoral neck and total hip, showing marked osteopenia in three cases and osteoporosis in the remaining three cases. However, at lumbar spine BMD measurement provided spuriously overestimated results, because of intervertebral disc calcification and osteophyte formation. As far as biochemical markers of bone turnover are concerned, the most relevant finding was the increased N-telopeptides of type I collagen urinary excretion. Our results suggest that ochronosis may be associated with increased bone resorption rate leading to an accelerated bone loss. A role of the homogentisic acid polymer deposit in bone matrix and cells, possibly with osteocyte damage and interference in collagen metabolism, might be hypothesized.

Absorptiometry, Photon↗
PubMed2003

Gallium scan in adolescents and children with Hodgkin's disease (HD). Treatment response assessment and prognostic value.

AIM: The aim of the present paper is to describe the accuracy of gallium ((67)Ga) scintigraphy in adolescents and children with Hodgkin's disease (HD). We have studied the diagnostic value of this nuclear imaging technique at disease presentation (staging) and its prognostic value based on changes in (67)Ga uptake observed after treatment (response assessment). METHODS: From April 1985 to July 1999 74 consecutive untreated patients with a median age of 13 y underwent (67)Ga scans 48-72 h after injection of 37-111 MBq of (67)Ga-citrate. Planar whole-body scintigraphy was performed, supplemented with single photon emission tomography (SPET) of the mediastinum from 1996 onwards. Three patients did not undergo further scintigraphic examination because they were treated with radical surgery. After the 1st examination 71 of the 74 patients were monitored by 1-3 (67)Ga scans during the course of their disease. All of them had at least one (67)Ga scintigraphy at the end of the induction phase of chemotherapy, before any other therapeutic regimens were planned. RESULTS: At disease presentation (67)Ga scintigraphy was positive in all patients, detecting 285 of 335 (85.0%) lymph nodal sites of disease. The best sensitivity was observed in the mediastinum (100%; 63/63) and the laterocervical supraclavicular region (85.6%; 125/146); it was lower for axillary (72.7%; 16/22) and retroperitoneal (68.7%; 11/16) lymph node masses. In detecting visceral involvement the sensitivity of (67)Ga scintigraphy was 66.6% (8/12) for lung and 80% (4/5) for bone involvement. Among 71 patients in follow-up, 2 showed rapid progression of disease during induction therapy while 69 patients were monitored for a long period. The response to therapy has been classified according to the changes observed on nuclear medicine or radiological images as complete response (CR) or partial response (PR). On the basis of (67)Ga scans 55 patients (72.4%) were considered as having a CR, while with radiological modalities (chest X-ray, CT, MRI) CR was observed in only 29 patients (40.8%). PR or progression was found with (67)Ga scintigraphy in 16 patients (22.5%) and with radiological modalities in 42 patients (59.1%). (67)Ga scan was concordant with clinical outcome in 97% (28/29). The diagnostic effectiveness of this imaging technique has been analysed by comparing the scintigraphic or radiological changes at the 1st scintigraphic/radiological follow-up examination after induction therapy with the clinical outcome. In this population the relapse rate was 50% (8/16) in the group that did not achieve a CR according to post-treatment (67)Ga scintigraphy, while it was only 10.9% (6/55) in the group that achieved a CR on the basis of scintigraphy findings. The overall survival (OS) and disease-free survival (DFS) were calculated by means of Kaplan-Meier cumulative survival plotting. When the 2 groups of patients with complete (CR) or incomplete normalisation (PR or progression) of (67)Ga scintigraphy were compared, both OS and DFS were found to be statistically different (p=0.0001 and p=0.0004, respectively). By contrast, no statistical difference was found when the radiological findings were considered as the criterion for assessment of tumour response. On the basis of X-ray results the relapse rate was 13.7% in patients with negative post-therapy findings and 23.8% in patients with positive radiological imaging. CONCLUSION: Our data demonstrate the high value of (67)Ga scintigraphy in HD staging in paediatric patients. In addition, evaluation of the (67)Ga uptake is very useful as a prognostic parameter; changes in (67)Ga uptake after therapy indicate a favourable prognosis, whereas children still positive on post-treatment (67)Ga scintigrams should be given more aggressive treatment.

Adolescent↗
PubMed2002

Uneven deficits in vertebral bone density in postmenopausal patients with primary hyperparathyroidism as evaluated by posterior-anterior and lateral dual-energy absorptiometry.

This investigation was undertaken to determine whether the preservation of bone mass in patients with mild primary hyperparathyroidism (PHPT) could be detected when measuring spine density in the lateral projection. We compared the bone mineral density (BMD) of L2-L4 utilizing the posterior-anterior (PA) and lateral projections in postmenopausal patients with PHPT and in a group of 27 postmenopausal normal women. Thirty-three consecutive postmenopausal patients with PHPT were studied; 25 were asymptomatic whereas the remaining 8 suffered complications related to the disease. Based upon the criteria established by the Consensus Conference on the Management of Asymptomatic PHPT, only 10 of the 25 asymptomatic patients could be considered affected by mild disease; the remaining patients were classified as having moderate disease. Patients with mild disease had mean lateral total BMD values (0.682 +/- 0.113 g/cm(2)) significantly higher than normal women (0.588 +/- 0.076, p<0.02) and patients with moderate disease (0.599 +/- 0.077, p<0.05). There were significant differences among the three groups in both PA L2-L4 and L1-L4 levels: patients with mild disease had significantly higher mean BMD values than patients with moderate disease and normal women, when either three or four vertebrae were considered. Interestingly, at this latter site, patients with moderate disease had significantly ( p<0.05) lower values than normal women. Our results indicate that patients with mild PHPT have a preservation of vertebral mass when compared with the other hyperparathyroid patients and normal women, when taking into account both the mainly trabecular portion and the whole vertebra. The finding that when the PA projection was assessed, BMD values of patients with moderate disease were significantly lower than those of normal women, might be attributed to the detrimental effect of raised parathyroid hormone levels on the cortical component of the vertebral body.

Absorptiometry, Photon↗
PubMed2002

The lungs and platelet production.

Several studies have suggested that thrombopoiesis may occur in the lungs. To investigate the role of the lungs in platelet production, we measured automated platelet parameters in blood from the pulmonary artery and the radial artery (n=125) or aorta (n=26) in patients undergoing aorto-coronary bypass. No significant differences were found between pulmonary and radial arterial blood with regard to platelet count (192.132 +/- 46.250 vs. 192.004 +/- 46.294 x 10(9)/l), mean platelet volume (11.03 +/- 1.04 vs. 11.03 +/- 1.03 fl), plateletcrit (0.212 +/- 0.051 vs. 0.212 +/- 0.051 x 10(-2)), platelet distribution width (14.48 +/- 2.16 vs. 14.47 +/- 2.08 fl) and platelet-large cell ratio (0.350 +/- 0.076 vs. 0.351 +/- 0.078). Similar results were obtained in comparisons between pulmonary arterial and aortic blood. A coefficient of linear correlation of 0.98 was found between the pulmonary and radial arterial and aortic platelet counts. These findings suggest that the platelet population entering the lungs was the same as the platelet population leaving them. Our results do not therefore support the theory of pulmonary platelet production.

Aged↗
PubMed2001

Positron emission tomography (PET) and other nuclear medicine modalities in staging gastrointestinal cancer.

Gastrointestinal (GI) cancers account for the second highest number of new tumor cases and deaths per year in the United States and Western Europe. The most frequently involved sites are, in descending order, the colorectum, stomach, pancreas, liver, bile duct, and esophagus. The most common tumor type is adenocarcinoma. Among the epithelial cancers, great attention has recently been given to the tumors of neuroendocrine origin. These concepts are relevant because nuclear medicine imaging is based on visualization by means of a particular uptake of radiolabelled tracers in cancer cells that concentrate the radioactive signal. This signal is detected and reconstructed in planar or tomographic images. Different radiopharmaceuticals have been proposed for diagnostic application in oncology (such as radiolabelled monoclonal antibodies (MAbs), receptor tracers, and positron-emitting radiopharmaceuticals), and they are currently used as tracers for tumor detection with different modalities and techniques. Most of these techniques demonstrate their clinical usefulness in the diagnosis of GI cancer. This work is not intended to be a comprehensive review of all the extensive experience and possibilities of nuclear medicine for the diagnosis of GI tumors; rather, it aims to summarize the current status of the most important approaches and their main indications in staging GI cancers.

Antibodies, Monoclonal↗
PubMed2001

Respiratory changes in human red cells.

To investigate physiological respiratory changes in human red cells, we measured automated red cell parameters in samples from the pulmonary and radial arteries of 86 patients undergoing aorto-coronary bypass and from the pulmonary artery and the aorta in 23 patients. Our results showed higher mean corpuscular volume (88.53 +/- 5.06 fl vs. 88.12 +/- 4.94 fl, P < 0.000001), haematocrit (0.369 +/- 0.039 vs. 0.367 +/- 0.038, P < 0.0005), red cell distribution width (43.38 +/- 4.16 vs. 43.04 +/- 4.05 fl, P < 0.000001) and a lower mean corpuscular haemoglobin concentration (338.3 +/- 15.9 vs. 339.9 +/- 16.8 g/l, P < 0.005) in pulmonary arterial as compared to radial arterial blood. There were no differences with respect to haemoglobin concentration, red blood cell count, or mean corpuscular haemoglobin. Similar differences were observed between pulmonary arterial and aortic blood. Our results suggest cyclic respiratory modifications of red cell parameters attributable to the CO2 Jacobs-Stewart cycle.

Carbon Dioxide↗
PubMed2001

Hormone metabolism in the pulmonary circulation.

We measured hormonal levels in blood samples from pulmonary and radial arteries in 117 patients undergoing aorto-coronary by-pass surgery with the aim of investigating the role of the pulmonary vessel endothelium in hormone metabolism. Insulin and glucagon concentrations were significantly higher in pulmonary artery blood with respect to radial artery blood (73 +/- 65 vs. 65 +/- 47 pmol/l, p < 0.005, and 80 +/- 49 vs. 73 +/- 51 ng/l, p < 0.01, respectively), while no difference was found for growth hormone, prolactin, C peptide, insulin-like growth factor I, follicle stimulating hormone, luteinizing hormone, thyroid stimulating hormone, parathyroid hormone, thyroglobulin, triiodothyronine, thyroxine, free triiodothyronine, and free thyroxine. Moreover, prolactin concentrations were more than twice the normal levels, this being an effect of propafol and the opiate fentanyl used for the general anesthesia. Assuming that the arteriovenous differences observed are a marker of peptide hormone degradation, our study has demonstrated that with similar kinetics insulin and glucagon secreted into portal circulation and escaping from hepatic extraction undergo further homeostatic removal of about 9-10 % in the pulmonary circulation before entering the general circulation.

Aged↗
PubMed2001

HLA antigens in alkaptonuric patients.

BACKGROUND: In alkaptonuric patients a disabling ochronotic arthropathy develops, due to the deposit of a pigmented polymer of homogentisic acid. Since in inherited diseases the clinical expressions may be multifactorial, involving genetic and environmental factors, where the HLA system may play a role, we studied HLA antigens in ochronotic patients. METHODS: The study was carried out in 21 members of three families of six ochronotic patients and in two isolated ochronotic patients. The HLA typing has been done testing for antigens from loci A, B and C, by international standard microlymphocytotoxicity method, and for loci DR and DQ, by fluorescence method on immunologically isolated cells by means of antibody-coated microspheres. The chi square test was used for statistical analysis, with Yates correction due to the low number of observations. RESULTS: Despite the limited number of subjects, due to the rarity of the disease, a significantly higher prevalence of HLA-DR7 antigen was found in the alkaptonuric patients when compared to a general population (p<0.02), suggesting a possible association, while the prevalence of HLA A, B, C and DQ showed no significant differences. CONCLUSIONS: It might play a role in the pathophysiology and in the clinical expression of the disease.

Alkaptonuria↗
PubMed2000

The acute myocardial infarction in very elderly.

A total 325 patients were studied at admission for myocardial infarction, measuring plasma fibrinogen (FBG), creatine phosphokinase (CPK) and lactate dehydrogenase (LDH) and automatized hemocromocytometric parameters in order to contribute to explain the excess mortality reported in very elderly patients. It was found that age positively correlated with fibrinogen and LDH values and inversely with CPK, hemoglobin concentration and lymphocyte count. The unpaired comparison of the variables studied in age subgroups showed no differences between patients aged 65 or less than 65 years and patients aged 66-75 years. In patients aged over 75 years FBG, neutrophile count and LDH were significantly higher in respect to 65 or less and 66-75 years age subgroups and hemoglobin concentration, red blood cell count, hematocrit and lymphocyte count were lower. In the very elderly patients the study shows a biochemical feature suggesting delayed hospitalization for myocardial infarction, that may contribute to their poorer prognosis.

Journal Article↗
PubMed2000

Osteocalcin metabolism in the pulmonary circulation.

The aim of this study was to evaluate the role of the pulmonary vessel endothelium in the removal of circulating osteocalcin, by measuring the osteocalcin levels in serum from pulmonary and radial artery blood from 39 patients undergoing aorto-coronary bypass. Because of the discrepancies between methods of measurement, two methods were used. Significant differences were observed in group A (n = 18), tested with heterologous radioimmunoassay (2.85 +/- 0.67 microg l-1 in the pulmonary versus 2.69 +/- 0.67 microg l-1 in the radial artery serum, P<0.001) and in group B (n = 21), tested with a two-site immunoradiometric assay (5.22 +/- 1.46 versus 4.93 +/- 1.36 microg l-1, P<0.01). The percentage differences were -5.54 +/- 4.76% (P<0.001) in group A and -4.99 +/- 8.13% (P<0.01) in group B; the comparison between the percentage differences was not significant. These different osteocalcin concentrations between the two vascular compartments were considered a marker of osteocalcin degradation. Therefore, the study seems to demonstrate that, as well as kidney, liver and bone, the lung is a relevant site of osteocalcin catabolism. The proteolytic activity of pulmonary vessel endothelium seems to involve about 5% of the circulating peptide.

Aged↗
PubMed2000

[Osteoporosis and phytoestrogens: an assessment of bone mineral density via quantitative peripheral computed tomography in milk-egg-vegetarian women in the premenopause].

PURPOSE: Noninvasive assessment of bone mineral density, geometrical and biomechanical properties in premenopausal women with dietary intake of phytoestrogens and comparison of these parameters with those of age-matched female subjects with "Mediterranean" dietary intake lacking in these substances. MATERIAL AND METHODS: Volumetric cortical, trabecular and total mineral density and bone geometrical properties were evaluated in 15 female subjects with phytoestrogens dietary intake. Peripheral quantitative Computed Tomography (pQCT) was used to make measurements at the distal radius of the nondominant forearm. Fifteen age-matched subjects with "Mediterranean" dietary intake were chosen as a control group. Cross-sectional area (Total A), trabecular area (TA), cortical area (CA), cortical thickness (CThk) and strength strain index (SSI) were assessed as biomechanical parameters. RESULTS: Daily consumption of phytoestrogens was significatively different in the two groups (phy: 17.45 mg/die vs ctr: 0.35; p < 0.0005), while calcium intake was similar (phy: 652 mg/die vs ctr: 650). Total (0.460 g/cm3 vs ctr: 0.433) and trabecular (phy: 0.209 g/cm3 vs ctr: 0.189) bone mineral densities, such as SSI (phy: 925 mm3 vs ctr: 894) values, were higher in women with dietary intake of phytoestrogens, in comparison with the relative controls, but not significantly (p = ns). Among geometrical parameters, total area and cortical area were tendential in women with a vegetarian diet while cortical thickness was the same in both groups. CONCLUSIONS: pQCT showed higher bone mineral density (total and trabecular) and SSI values in premenopausal women with dietary intake of phytoestrogens. Despite the lack of statistical significance, these preliminary results, should further support the few literature findings about the potential role of phytoestrogens consumption in preventing trabecular bone loss. However, further studies are warranted to evaluate definitively the efficacy of phytoestrogens in preventing postmenopausal osteoporosis.

Adult↗
PubMed2000

Role of monocytes in the early phase of acute myocardial infarction.

BACKGROUND: In acute myocardial infarction peripheral leucocytosis occurs early and fibrinogen levels increase in response to the tissue injury, expressed by the enhanced enzyme plasma levels. The aim of the present study has been to investigate if a unifying link between these modifications might be found. METHODS: In 325 patients, 246 men and 79 women, 61.46 +/- 11.00 and 70.03 +/- 11.30 years mean age respectively, at admission for myocardial infarction and before treatment, we simultaneously measured plasma fibrinogen (FBG), hemochromocytometric parameters and plasma enzyme aspartate and alanine transaminase (AST and ALT), lactate dehydrogenase (LDH) and creatine phosphokinase (CPK). The statistical analysis was performed by using standard multiple regression for dependent variable FBG and for the variables white blood cells (WBC), monocyte number, large unstained cells (LUC) and CPK. RESULTS: The results showed that FBG was significantly correlated with monocyte (p < 0.001) and LUC (p < 0.05) counts; assumed as dependent variable, further on with FBG, monocyte number was correlated with WBC count, LUC and CPK; further on with monocyte number, WBC with neutrophile and lymphocyte counts, LUC with CPK, CPK with LDH. CONCLUSIONS: The study seems to show that monocyte modifications occur already in the early phase of myocardial infarction. These modifications are directly related to damage extension, as deducible from CPK levels, and seem to mainly modulate FBG and WBC, since the cytokines and hematopoietic growth factors production by activated monocytes.

Acute Disease↗
PubMed1999

[Assessment of geometric, biomechanical, and osteodensitometric properties of the ultradistal radius with peripheral quantitative computerized tomography in uremic patients with severe hyperparathyroidism].

INTRODUCTION: Bone integrity and mineral status were studied with a noninvasive method in uremic patients with severe secondary hyperparathyroidism undergoing maintenance hemodialysis. MATERIAL AND METHODS: Volumetric cortical and trabecular mineral density (cBMD, tBMD) and bone geometrical properties were evaluated in 16 patients (11 women and 5 men) candidate to parathyroidectomy. Peripheral quantitative Computed Tomography (pQCT) was used to make measurements at the distal radius of the nondominant forearm. Thirty-two age-matched healthy subjects were chosen as a control group. Cortical area (CA), cross-sectional area (Total A), cortical thickness (CThk) and stress strain index (SSI) were assessed as biomechanical parameters. Serum intact PTH levels were assessed with a radioimmunoassay method (IRMA). RESULTS: Both cBMD and tBMD were decreased in all patients and the difference was more significant in women (p < .0004 and p < .009) than in the smaller group of men (p < .01 and p < .01). Serum PTH levels correlated negatively with cBMD (r = .52; p < .01), CThk (r = .51; p < .04), CA (r = .52; p < .03) and SSI (r = .54; p < .02), as well as tBMD (r = .34), though not significantly. Dialysis duration did not significantly correlate with cBMD (r = .33), tBMD (r = .20), CA (r = .31), CThk (r = .40) and SSI (r = .35). As for geometrical and biomechanical parameters, CA, CThk and SSI were significantly different in both male and female uremic patients in comparison with the relative controls. Bone quantitative analysis and three-dimensional (3D) representation with the paraboloid revolution model also demonstrated osteopenia. CONCLUSIONS: pQCT shows significant cortical and trabecular osteopenia in uremic patients with severe secondary hyperparathyroidism. Osteopenia is associated with geometrical and mechanical impairment with consequently increased bone fragility and thus a higher risk of fracture. Prolonged PTH hyperexpression seems to be mainly associated with intracortical porosity and cortical-endosteal resorption. Bone quantitative analysis and 3D representation provide rapid automated information on the cortex mineral status.

Adult↗
PubMed1998

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.

Adult↗
PubMed1997

The measurement of urinary amino-terminal telopeptides of type I collagen to monitor bone resorption in patients with primary hyperparathyroidism.

This study was carried out in order to evaluate clinical usefulness of cross-linked N-telopeptides (NTx) of type I collagen determination, in patients with primary hyperparathyroidism. Twenty-six consecutive patients (6 males and 20 females, aged 56.3 +/- 15.0, SD, yrs) with primary hyperparathyroidism were studied in basal conditions and, ten of them, after surgical cure of the disease. Cross-linked collagen peptides were measured by enzyme-linked immunosorbent assay and conventional markers of bone turnover according to standard procedures. Bone densitometry at the lumbar spine and proximal femur was performed using dual-energy X-ray absorptiometry. Bone mineral density, was also assessed at the junction of the distal and middle third of the radius and at the ultradistal radius of the non-dominant arm by a dual photon densitometer. Mean urinary NTx values (194.2 +/- 121.9 pmoles bone collagen equivalents/mumoles creatinine) were significantly higher (p < 0.001) in respect to those found in normal subjects. The mean increase of Z score values of both serum tartrate resistant acid phosphatase activity (1.4 +/- 1.8) and the fasting hydroxyproline/creatinine ratio (1.45 +/- 2.0) was significantly lower (p < 0.02) in respect to that of NTx Z score values (3.3 +/- 3.3); the latter values were not significantly different than mean Z score values of serum osteocalcin (4.0 +/- 3.9), serum alkaline phosphatase activity (2.6 +/- 2.6) and urinary calcium/creatinine ratio (3.2 +/- 3.3). We found a significant inverse correlation between NTx values and both lumbar spine (p < 0.01) and ultradistal radius bone mineral density (p < 0.05); a modest inverse correlation was also observed between serum tartrate resistant acid phosphatase activity and lumbar spine bone mineral density (p < 0.04). Following successful adenoma removal, the percentage decrease of both NTx and hydroxyproline was similar in patients with increased bone turnover rate; major discrepancies were observed in patients with normal values of NTx, the telopeptide reduction being greater than that of hydroxyproline. Finally, in a hypercalcemic patient with metastatic parathyroid cancer, telopeptide excretion was shown to be more sensitive in respect to urinary hydroxyproline when evaluating the effects of antiresorptive therapy. Our results seem to indicate that amongst the markers with good sensitivity, NTx is the only one that is inversely related with bone mineral density at two different skeletal sites. This assay should therefore have a place in both the initial screening and medical follow-up of patients with this glandular disorder; in fact, in both situations an increased urinary excretion of this marker should warn about the possibility of hidden bone loss.

Absorptiometry, Photon↗