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31.
BackgroundMost vertebral compression fractures are not recognized or treated. We conducted a controlled trial in older patients with vertebral fractures incidentally reported on chest radiographs, comparing usual care with osteoporosis interventions directed at physicians (opinion-leader-endorsed evidence summaries and reminders) or physicians+patients (adding activation with leaflets and telephone counseling).MethodsPatients aged >60 years who were discharged home from emergency departments and who had vertebral fractures reported but were not treated for osteoporosis were allocated to usual care (control) or physician intervention using alternate-week time series. After 3 months, untreated controls were re-allocated to physician+patient intervention. Allocation was concealed, outcomes ascertainment blinded, and analyses intent-to-treat. Primary outcome was starting osteoporosis treatment within 3 months.ResultsThere were 1315 consecutive patients screened, and 240 allocated to control (n = 123) or physician intervention (n = 117). Groups were similar at baseline (average age 74 years, 45% female, 58% previous fractures). Compared with controls, physician interventions significantly (all P <.001) increased osteoporosis treatment (20 [17%] vs 2 [2%]), bone mineral density testing (51 [44%] vs 5 [4%]), and bone mineral density testing or treatment (57 [49%] vs 7 [6%]). Three months after controls were re-allocated to physician+patient interventions, 22% had started treatment and 65% had bone mineral density testing or treatment (P <.001 vs controls). Physician+patient interventions increased bone mineral density testing or treatment an additional 16% compared with physician interventions (P = .01).ConclusionsAn opinion-leader-based intervention targeting physicians substantially improved rates of bone mineral density testing and osteoporosis treatment in patients with incidental vertebral fractures, compared with usual care. Even better osteoporosis management was achieved by adding patient activation to physician interventions [NCT00388908].  相似文献   
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Histoplasmosis is usually an opportunistic fungal infection in patients with defective cell mediated immunity, and has been considered as one of the acquired immunodeficiency syndrome (AIDS) defining illness. However, cutaneous involvement in human immunodeficiency virus (HIV) positive patients is less common, and very rarely can be the initial presenting symptom for the diagnosis of AIDS. We present here an unusual case of multiple diffuse cutaneous nodular lesions predominantly in face, trunk, and upper extremities diagnosed initially on aspiration cytology as histoplasmosis. Subsequent serological test revealed positivity for HIV 1 and 2, along with a low CD4 count and low CD4:CD3 ratio. The cytomorphological features were further corroborated by histology and histochemical stains. Hence, cutaneous histoplasmosis can cause multiple wide spread nodular or umbilicated lesions in AIDS patients as the initial presentation. Fine needle aspiration cytology (FNAC) is a rapid, cost effective tool for diagnosis of the fungi from such lesions and initiating work up for immunocompromised states including AIDS. Diagn. Cytopathol. 2013. © 2011 Wiley Periodicals, Inc.  相似文献   
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High‐resolution peripheral quantitative computed tomography (HR‐pQCT) has recently been introduced as a clinical research tool for in vivo assessment of bone quality. The utility of this technology to address important skeletal health questions requires translation to standardized multicenter data pools. Our goal was to evaluate the feasibility of pooling data in multicenter HR‐pQCT imaging trials. Reproducibility imaging experiments were performed using structure and composition‐realistic phantoms constructed from cadaveric radii. Single‐center precision was determined by repeat scanning over short‐term (<72 hours), intermediate‐term (3–5 months), and long‐term intervals (28 months). Multicenter precision was determined by imaging the phantoms at nine different HR‐pQCT centers. Least significant change (LSC) and root mean squared coefficient of variation (RMSCV) for each interval and across centers was calculated for bone density, geometry, microstructure, and biomechanical parameters. Single‐center short‐term RMSCVs were <1% for all parameters except cortical thickness (Ct.Th) (1.1%), spatial variability in cortical thickness (Ct.Th.SD) (2.6%), standard deviation of trabecular separation (Tb.Sp.SD) (1.8%), and porosity measures (6% to 8%). Intermediate‐term RMSCVs were generally not statistically different from short‐term values. Long‐term variability was significantly greater for all density measures (0.7% to 2.0%; p < 0.05 versus short‐term) and several structure measures: cortical thickness (Ct.Th) (3.4%; p < 0.01 versus short‐term), cortical porosity (Ct.Po) (15.4%; p < 0.01 versus short‐term), and trabecular thickness (Tb.Th) (2.2%; p < 0.01 versus short‐term). Multicenter RMSCVs were also significantly higher than short‐term values: 2% to 4% for density and micro–finite element analysis (µFE) measures (p < 0.0001), 2.6% to 5.3% for morphometric measures (p < 0.001), whereas Ct.Po was 16.2% (p < 0.001). In the absence of subject motion, multicenter precision errors for HR‐pQCT parameters were generally less than 5%. Phantom‐based multicenter precision was comparable to previously reported in in vivo single‐center precision errors, although this was approximately two to five times worse than ex vivo short‐term precision. The data generated from this study will contribute to the future design and validation of standardized procedures that are broadly translatable to multicenter study designs. © 2013 American Society for Bone and Mineral Research.  相似文献   
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Men who fracture have greater mean bone mineral density (BMD) than women who fracture, and to some this suggests that BMD fracture “thresholds” are greater in men than women, justifying use of a male BMD reference standard. Others disagree and argue that because BMD distribution in men is right-shifted (higher) compared with women, anything that occurs with equal probability for men and women will occur at a greater mean BMD in men. If the latter is true, it supports using a common (female) BMD reference standard. We directly tested this latter principle and, indirectly, the validity of using a constant BMD reference standard, in 51,326 women (3722 major fractures) and 4691 men (276 fractures), by comparing mean BMD in fracture vs nonfracture groups defined by sex, age, race and body mass index because these 4 factors affect both mean BMD and risk of fractures. Among those who fractured, mean BMD for all measurement sites were significantly greater in men vs women, youngest vs oldest, whites vs Asian, and heaviest vs the lightest (all p < 0.001). However, the same BMD pattern was seen in those who did not fracture and the absolute difference in BMD between those who fractured and those who did not was essentially constant regardless of sex, age, race, or weight class (all p-interaction nonsignificant). This finding suggests that use of a common reference standard for BMD (i.e., young white women) for men, and indeed all subgroups defined by osteoporosis risk factors, is reasonable and consistent with empiric observations.  相似文献   
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Osteoporotic fractures are associated with excess mortality and decreased functional capacity and quality of life. Age-standardized incidence rates of fragility fractures, particularly of the hip and forearm, have been noted to be decreasing in the last decade across many countries with the notable exception of Asia. The causes for the observed changes in fracture risk have not been fully identified but are likely the result of multiple factors, including birth cohort and period effects, increasing obesity, and greater use of anti-osteoporosis medications. Changing rates of fragility fractures would be expected to have an important impact on the burden of osteoporosis.  相似文献   
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This study assessed the effects of static loading on MRI relaxation times of menisci in individuals with and without radiographic knee OA. High‐resolution fast spin‐echo (FSE) and T1ρ/T2 relaxation time MR sequences were obtained with and without loading at 50% body weight in 124 subjects. T/T2 relaxation times were calculated in menisci, and meniscus lesions were assessed through clinical grading. Student's t‐test compared OA and control unloaded relaxation times as well as within‐group changes with loading, Generalized Linear Models evaluated zonal variation, and ANCOVA compared loading response between groups. Unloaded T and T2 in the middle and inner zones of the lateral anterior horn and outer zone of the medial posterior horn were significantly higher in OA and suggest that meniscal OA change occurs unevenly. Zonal T and T2 showed differing patterns between anterior and posterior horns, suggesting differences in macromolecular organization. Significant increases with loading were seen largely in the T2 of controls and less frequently in subjects with OA. In the medial posterior horn, T and T2 decreased with loading in OA but changed negligibly in controls; these significantly different loading responses between groups may indicate load transmission failure in OA menisci. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:249–261, 2016.  相似文献   
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