Coronary-artery calcification is common and progressive in young adults with end-stage renal disease who are undergoing dialysis.

Emphysema results from progressive destruction of alveolar septae and was considered irreversible until all-trans-retinoic acid (ATRA) was shown to reverse anatomic and physiologic signs of emphysema in a rat model. To evaluate the feasibility of ATRA as a clinical therapy, 20 patients with severe emphysema were enrolled into a randomized, double-blind, placebo-controlled pilot study. Participants included 16 male and 4 female former smokers, two with alpha(1)-antitrypsin deficiency. Patients were treated with either 3 mo of ATRA (50 mg/m(2)/d) or 3 mo of placebo, followed by a 3-mo crossover phase. Plasma drug levels were followed and outcome measures included serial pulmonary function tests, blood gases, lung compliance, computed tomography (CT) imaging, and quality of life questionnaires. In general, treatment was well tolerated and associated with only mild side effects including skin changes, transient headache, hyperlipidemia, transaminites, and musculoskeletal pains. Plasma drug levels varied considerably between subjects and decreased significantly over time in 35% of the participants. Physiologic and CT measurements did not change appreciably in response to therapy. We conclude that ATRA is well tolerated in patients with emphysema, and trials evaluating higher doses, longer treatment, or different dosing schedules are feasible.

In asymptomatic subjects, the initial CCS and CVS were the most important factors that affected rate of coronary artery calcium progression. Neither age nor sex was as important as these factors in determination of coronary artery calcium progression.

Spiral CT has not yet proved to be a feasible alternative to electron-beam CT for coronary artery calcium quantification. There are systematic differences between calcium scores obtained with single-detector array subsecond spiral CT and those obtained with electron-beam CT.

No abstract

Peripheral quantitative computed tomography (pQCT) can selectively measure the densities of cortical and trabecular bone, but there is limited information about its use in patients with renal osteodystrophy. Thus pQCT (Norland XCT-2000, Stratec, Pforzheim, Germany) was performed at the ultradistal radius in 21 patients aged 16±3.6 (SD) years on continuous cycling peritoneal dialysis. Trabecular bone density (TBD) was higher in patients, 206±16 mg/cm 3 , than in controls, 182.7±24.8 mg/cm 3 (P<0.0001), whereas cortical bone density (CBD) was lower in patients, 946.5±147.5 mg/cm 3 , than in controls, 1,153±25.4 mg/cm 3 (P<0.001). TBD was inversely correlated with age (r=−0.59, P=0.05), height (r=−0.59, P<0.01), and weight (r=−0.51, P<0.05). In contrast, CBD was positively correlated with age (r=0.53, P<0.05), height (r=0.56, P<0.05), and weight (r=0.53, P<0.05). CBD was inversely related to serum alkaline phosphatase (r=−0.71, P<0.001) and parathyroid hormone levels (r=−0.50, P<0.05). In patients with adynamic bone, TBD was less, 192±9 mg/cm 3 , than in those with high-turnover lesions, 215±13 mg/cm 3 , P<0.001. CBD, however, was lower in patients with high-turnover lesions, 900±151 mg/cm 3 , than in those with low turnover, 1,022±111 mg/cm 3 , P<0.05. Compared with controls, in patients with high-turnover lesions, CBD was lower (P<0.0001) and TBD higher (P<0.0001). These findings suggest that pQCT may be an additional tool in the assessment of renal osteodystrophy.

A retrospective medical record review was performed to study the differences in clinical risk profiles and the relationships between test results versus management for suspected pulmonary thromboembolism (TE) in patients undergoing either radionuclide ventilation perfusion (V/Q) scans or pulmonary computed tomographic angiography (CTA), as the initial test. Data of 138 consecutive V/Q patients were compared with that of 149 consecutive CTA patients during equivalent 6-month intervals before and after the introduction of CTA. Information on risk factors, signs and symptoms, all diagnostic test results, and the relationships between the test results and ultimate physician management were collected and analyzed. V/Q results predicted physician management in all patients with high probability scans and 91% with normal to low probability scans. There were 35 patients with indeterminate V/Q scans--43% of these patients were managed without any other diagnostic test. CTA results predicted management in all patients with positive studies and 99% of patients with negative studies. In contrast to the V/Q cohort, only seven CTA studies were inconclusive--additional diagnostic tests determined management in all but one case. Compared with V/Q, CTA has fewer indeterminate results, is more directly reflective of management, and reduces the number of patients managed with inconclusive data.