Quantitative ultrasound technology in evaluating bone status and osteoporosis in patients with Cushing's syndrome.

Osteoporosis is a major feature of Cushing's syndrome (CS), and fragility fractures may be the first sign of the disease. The aim of this study was to evaluate the ability of quantitative ultrasound technology (QUS) in diagnosing osteoporosis in patients with CS. Sixty-three consecutive patients (mean age 38.6 +/- 13.0 years), 13 (20.6%) men and 50 (79.4%) women, with confirmed CS underwent both dual-energy X-ray densitometry (DXA) and QUS. Two groups of patients were selected: group A, 23 patients, T-score -2 SD or less (bone mineral density [BMD] femoral neck < or = 695 g/cm(2)), and group B, 40 patients, T-score above -2 SD. Age (42 +/- 12 vs. 37 +/- 13 years) and 24-h free urinary cortisol (499 +/- 345 vs. 469 +/- 319 microg/day) did not differ significantly (P = NS) between groups, while the body mass index did (24.3 +/- 4.1 vs. 28.1 +/- 4.6, P = 0.002). Unlike DXA, QUS values did not differ significantly (P = NS) between groups. Moreover, in the overall population, as well as in a single group, there was no correlation (R < 0.5, P = NS) between QUS and DXA parameters. In conclusion, in our study QUS was not able to differentiate osteoporotic patients from those with normal BMD measured by DXA, and thus QUS technology should not be used to discriminate between osteopenic and nonosteopenic patients with CS.

Quantitative bone ultrasound at phalanges and calcaneus in osteoporotic postmenopausal women: influence of age and measurement site.

Phalangeal and calcaneal quantitative ultrasound (QUS) measurements were tested in a postmenopausal osteoporotic population of a wide age range to assess their ability to identify subjects with vertebral fractures in a population of postmenopausal women with osteoporosis. A group of 127 osteoporotic women aged from 50 to 85 y, who had been postmenopausal for at least 5 y, were enrolled. All subjects underwent phalangeal and calcaneal QUS measurements, femoral neck and lumbar spine dual energy X-ray absorptiometry (DXA) measurements and lateral thoracic and lumbar spine radiography. Osteoporosis was defined on the basis of femoral neck or lumbar spine bone mineral density (BMD) T-score lower than -2.5 SD or of the presence of one or more vertebral atraumatic fractures, independently of BMD values. Fifty-two women had one or more vertebral fractures, while the remaining 75 had no evidence of previous fracture. Both QUS techniques were able to discriminate between fractured and nonfractured subjects in the whole group (p < 0.05). When patients aged <70 y (n = 43) and patients aged > or = 70 y (n = 84) were considered separately, phalangeal QUS and lumbar spine BMD were able to discriminate vertebral fractures in the younger group (p < 0.05), whereas calcaneal QUS was able to discriminate vertebral fractures in the older one (p < 0.05). The results of this study raise an issue of the optimal use of different QUS techniques and different skeletal sites in the management of osteoporosis in early or late postmenopausal life.