[Bone mass, bone metabolism, and prevalence of spinal fractures in recipients of allogenic bone marrow transplantation for leukemia]. / Massa ossea, metabolismo scheletrico e prevalenza delle fratture vertebrali in pazienti precedentemente sottoposti a trapianto di midollo osseo allogenico per leucemia.

The aim of this study was to evaluate in 65 patients, who had previously undergone allogenic bone marrow transplantation (ABMT), the bone mineral density (BMD), the skeletal turnover and the prevalence of vertebral fractures. At the moment of recruiting, 10 of 65 transplanted subjects (15.3%) presented with signs of rejection of the transplanted tissue, thus they were excluded. The remaining 55 patients (21 males, 34 females, mean age 30.8 +/- 6.4 years), with a follow-up of 60 +/- 9 months after the transplant and without any treatment inducing osteopenia, underwent ABMT respectively for: chronic myeloid leukemia (n = 24); acute myeloid leukemia (n = 18); acute lymphatic leukemia (n = 13). One hundred and ten healthy control subjects (42 males and 68 females, mean age 31.0 +/- 3.7 years) matching with the patients for age, weight and height, were successively enrolled. All the participants were submitted to a densitometric evaluation (DEXA) of lumbar spine (L1-L4), of femoral neck and total femur; besides some skeletal metabolism parameters were dosed, such as: total alkaline phosphatase, bone alkaline phosphatase and urinary excretion of C-terminal telopeptide fragments normalized to creatinine. On the contrary, the morphometric evaluation, performed through a lateral dorsolumbar radiography, was actually carried out only in patients who had already undergone ABMT. The L1-L4 BMD study showed: 10/55 osteoporotic (18.1%), 19/55 osteopenic (34.5%) and 26/55 normal patients (47.4%). In transplanted patients BMD values, obtained at the three considered sites, resulted significantly reduced (p < 0.01) in comparison to controls. Moreover, in patients who underwent ABMT, a statistically significant increase was observed, in comparison to healthy subjects, in total alkaline phosphatase (p < 0.01), in bone alkaline phosphatase (p < 0.01) and in urinary excretion of C-terminal telopeptide fragments normalized to creatinine levels (p < 0.001). Seven of the 55 transplanted patients (12.7%) presented at the moment of Rx morphometric evaluation at least one vertebral fracture: 6 of whom were affected by osteoporosis and 1 by osteopenia. In conclusion, the subjects who had previously undergone ABMT maintain, even at a certain time after the transplant and without any rejection, an increased skeletal turnover and BMD values meanly lower than normal, leading to an increased risk for vertebral fracture.

High plasma adrenomedullin concentrations in patients with high-renin essential hypertension.

Adrenomedullin (AM) is a novel peptide, first isolated from human phaeochromocytoma, which elicits a long-lasting vasorelaxant activity. Recently, it has been reported that endothelial cells produce AM and that immunoreactive AM plasma levels may be elevated in human arterial hypertension, although the exact pathophysiological role of AM remains to be established. The aim of our study was to determine the relationship between the components of the enin-angiotensin-aldosterone system (RAAS) and plasma AM levels in patients with low-, medium- or high- renin essential hypertension. The study groups included 10 patients with low-renin essential hypertension (average age 42+15 years), nine patients with medium-renin essential hypertension (46+13 years), 11 patients with high-renin essential hypertension (42+14 years) and 12 healthy subjects (43+11 years). Our results demonstrated that the mean AM values of all patients with essential hypertension were 10.85+3.14 pg/ml; there was a statistical correlation (r=0.705; p<0.001) between plasma renin activity (PRA) and AM levels in hypertensives. In patients with high-renin essential hypertension, plasma AM levels (14.2+2.2 pg/ml) were significantly higher (p<0.001) than those of healthy subjects (8.7+2.1 pg/ml), patients with medium-renin essential hypertension (8.5+1.4 pg/ml), and patients with low-renin essential hypertension (9.1+1.5 pg/ml). There was no statistical difference in AM concentrations between medium- and low-renin hypertensive patients. In conclusion, we have found that, in hypertensive patients, plasma AM levels were increased only in high-renin individuals, suggesting a role of AM in this particular form of human essential hypertension.