Sergio Modoni

Longitudinal Evaluation of Vitamin D Status in Healthy Subjects from Southern Italy: Seasonal and Gender Differences

Abstract: 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.

Gastrointestinal motor dysfunction, symptoms, and neuropathy in noninsulin-dependent (type 2) diabetes mellitus

Although relatively frequent. diabetic involvement of digestive tract motility has not been investigated extensively in different organs. The authors studied esophageal, gastric, and gallbladder motor function in 35 type 2 (noninsulin-dependent) diabetic patients to determine the extent of gut involvement. Of these patients, 27 (77%) had peripheral neuropathy, 12 (34%) had both peripheral and autonomic neuropathy, and 22 (63%) had gastrointestinal symptoms. Esophageal manometric abnormalities were recorded in 18 patients, and delayed radionuclide emptying of the esophagus was documented in 16 patients, with a 83% concordance between the two tests. Scintigraphic gastric emptying of solids was delayed in 56% of patients, whereas gallbladder emptying after cholecystokinin stimulation was reduced in 69% of them. In 74% of patients at least one of the viscera under investigation showed abnormal motor function; however, only 36% of patients displayed involvement of the three organs. Gastrointestinal symptoms, duration and therapy of diabetes, previous poor glycemic control, and retinopathy did not correlate with the presence or the extent of motor disorders. Neuropathy was not predictive of gastrointestinal involvement and its extent; however, when motor abnormalities were present in patients with neuropathy, these were usually more severe. Gastrointestinal motor disorders are frequent and widespread in type 2 diabetics, regardless of symptoms. Autonomic neuropathy has a poor predictive value on motor disorders (0.75 for the esophagus, 0.5 for the stomach, 0.8 for the gallbladder), thus suggesting the coexistence of other pathophysiologic mechanisms.

Clinical results of recombinant erythropoietin in transfusion-dependent patients with refractory multiple myeloma: role of cytokines and monitoring of erythropoiesis

Abstract:  Recombinant erythropoietin (r‐EPO) was administered to 37 patients with advanced, transfusion‐dependent and chemo‐resistant multiple myeloma (MM), at the fixed dose of 10,000/U s.c, 3 times a week, for 2 months. Thirteen patients (35.1%) achieved a significant response in terms of complete abolition of red cell transfusions. Factors significantly predictive of response were: a) inappropriate production of endogenous EPO, as expressed by a reduced observed/predicted ratio; b) presence of a consistant number of circulating erythroid precursors BFU–E; c) low serum levels of tumor necrosis factor (TNF) and interleukin‐1 (IL‐1), cytokines with inhibitory activity on erythropoiesis; d) a single line of previously received chemotherapy. Renal failure, bone marrow plasma cell infiltration, serum levels of IL‐6 and other main clinical and laboratory parameters did not affect significantly the response to r‐EPO. High fluorescence reticulocytes (HFR) and soluble transferrin receptor (sTfR) values were useful to detect an early stimulation of erythropoiesis in responders, while a high percentage of circulating hypochromic erythrocytes (HE), as assessed by an automated counter, identified those patients developing functional iron deficiency during r‐EPO treatment. We conclude that about one‐third of severely anemic patients with advanced MM, unresponsive to chemotherapy, may benefit by r‐EPO therapy. The clinical management of these patients can be accomplished using non‐invasive parameters, such as sTfR, HFR and HE.

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 (Wards 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.

Gallbladder function and gastric liquid emptying in achalasia

Because of evidence that the abnormalities in achalasia are not restricted to the distal esophagus, we investigated gallbladder function by cholescintigraphy in the steady state and in response to CCK and the scintigraphic gastric emptying of a liquid caloric meal in 10 individuals with achalasia and 10 normal controls. No abnormalities were found during the filling phase of the gallbladder but seven of the 10 patients showed a 50% reduction in the ejection fraction (39.4%±30.4 vs 80.3±8.3 of controls, mean±sd,P=0.007) and a slower than normal ejection phase (9.1%/min±6.6 vs 18.1±4.5,P=0.02. In eight of the 10 patients, gastric liquid emptying was accelerated with a T1/2 of 41.5 min±15.4 vs 74.7 min±11.5 in the controls (P=0.007). It is concluded that in some achalasia patients extraesophageal functional abnormalities of the gastrointestinal tract may be found. Whether these findings are promoted by degenerative changes of extraesophageal nerve fibers as well as their clinical significance require further investigations.

Prognostic relevance of serum thymidine kinase in primary myelodysplastic syndromes: relationship to development of acute myeloid leukaemia

The aim of this study was to evaluate the possible prognostic relevance of thymidine kinase serum levels (s‐TK), an indirect marker of proliferative activity, in myelodysplastic syndromes (MDS). S‐TK levels were monitored by means of a radioenzyme assay in 90 patients affected by MDS (22 refractory anaemia, RA; 17 RA with ring sideroblasts, RARS; 21 RA with blast excess, RAEB; 15 RAEB in transformation, RAEB‐T; 15 chronic myelomono‐cytic leukaemia, CMMoL). Mean s‐TK levels (U//tl) measured at diagnosis were 11–9 –12–6 for RA, 11–4–13′6 for RARS, 19–9 – 28–4 for RAEB, 39–6 – 34–3 for RAEB‐T and 77–7 – 69–7 for CMMoL (normal values <5U//LI1). With the only exception of a weak relationship with lactate dehydrogenase, no correlation was found between initial s‐TK values and other clinical or laboratory parameters, such as age, haemoglobin, white blood cell or platelet count, percentage of bone marrow blasts. MDS patients with s‐TK >38 V/fA, a cut‐off level selected by means of ROC statistical analysis, showed a significantly shorter survival than those with s‐TK <38U//xl (8–2 v 37–4 months, respectively; P < 0–0001). In particular, transformation in acute myeloid leukaemia (AML) occurred in 17/21 (81%) of patients with s‐TK >38U//d and 9/69 (13%) of those with lower levels at diagnosis (P < 00001), independently of FAB subtype. High s‐TK levels were also useful to predict evolution in AML during the course of the disease in patients with normal initial values. Multivariate analysis confirmed the independent prognostic value of s‐TK on both overall survival and risk of acute transformation. We conclude that s‐TK may be an important prognostic factor in MDS, strongly correlated with development of AML.

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.

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

Abstract: This study aimed to clinically validate the global skeletal uptake (GSU) of 99mTc-methylene diphosphonate (99mTc-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 99mTc-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 mg/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 mg/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 mg/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.

Reduction of mononuclear cytokine production in hemodialysis patients treated with steam-sterilized low-flux polysulphone membranes.

An increased cytokine production, correlated with long term complications of uremic disease, has been described during hemodialysis. To identify possible differences in the cytokine release of differently sterilized membranes, we enrolled six uremic patients on chronic hemodialysis. The patients underwent dialysis with ETO-sterilized low-flux polysulphone membranes (F6, Fresenius AG) for at least three months (At), they were then switched to steam-sterilized polysulphone membranes (F6-HPS Fresenius AG) and further evaluations after one (B1) and two months (B2) were carried out. A final evaluation (A2) was made one month after switching back to F6 dialyzers. At each time period, samples were drawn to measure IL-1B released by cultured mononuclear cells (MN). Moreover, dialysate samples were collected to test endotoxin levels. C3a and C5a levels were assessed at 0, 5, 15 and 60 min from starting hemodialysis. Anti-ETO IgE levels were also assayed at A1, B1 and A2. The LAL test revealed a good quality dialysate. The mean pre-dialysis IL-1B levels were 215 pg/million cells at A1; falling to 49 at B1, and 54 at B2 (p≤0.01); there was then a sharp rebound at A2:284, p≤0.01. Post-dialysis levels followed the same pattern. No correlation between the dialysate endotoxin level and cytokine release was found. Complement activation did not change and in all the phases of the study no anti-ETO IgE was detected in any of the subjects. Our data suggest that the steam sterilized polysulphone membrane induces a lower cytokine release than the ETO sterilized membrane, although the mechanism by which it does so remains to be clarified.

Evaluation of different beta-counting systems involved in 90Y-Zevalin quality control.

Background90Y-ibritumomab tiuxetan (90Y-Zevalin) is currently approved for radioimmunotherapy of patients with relapsed or refractory low-grade, follicular, or transformed B-cell non-Hodgkins lymphoma. The radioimmunoconjugate may be administered to the patient only if the radiolabelling yield is higher than 95%. AimTo evaluate different methods of quality control testing for an accurate and rapid determination of radiolabelling yield in the clinical routine. MethodsFive beta-counting systems, involved in determining the yield of radiolabelled 90Y-Zevalin, were compared: an autoradiography system (AS), a thin-layer chromatography (TLC) scanner system, a dose calibrator (DC), a liquid scintillation analyser (LSA) and high-performance liquid chromatography (HPLC). These instruments were also analysed in terms of efficiency, spatial resolution, analysis time, operating procedure level, cost and availability. ResultsRadiolabelling yields were comparable among all instruments except for DC whose values were dubious. Efficiency was 1.5±0.11 MDLU·s−1 for the AS (where DLU means digital light unit), 3.5±0.2 kcps for the TLC analyser, 0.74±0.02 MBq for the DC, 15±0.12 kcps for LSA and 180±0.07 kcps for HPLC. Spatial resolution was 1 mm for AS and 5 mm for the TLC analyser. The quality control test needed 8 min with AS and DC, 15 min with TLC and LSA, and 50 min with HPLC. ConclusionsThe short analysis time, high sensitivity, simultaneous detection of multiple radioactive strips and low cost offered by AS make it a suitable tool for radioactivity analysis and quantification in a radiopharmacy laboratory.