Renal arterial stenosis: prospective comparison of color Doppler US and breath-hold, three-dimensional, dynamic, gadolinium-enhanced MR angiography.

PURPOSE: To compare color Doppler ultrasonography (US) with fast, breath-hold, three-dimensional, gadolinium-enhanced magnetic resonance (MR) angiography in detecting renal arterial stenosis. MATERIALS AND METHODS: Forty-five patients with clinical suspicion of renovascular disease were prospectively examined with intra- and extrarenal color Doppler US and breath-hold, gadolinium-enhanced MR angiography. Digital subtraction arteriography (DSA) was the standard of reference in all patients for the number of renal arteries and degree of stenosis. RESULTS: DSA depicted 103 arteries and 52 stenoses. Color Doppler US was nondiagnostic in two examinations. Significantly more of 13 accessory renal arteries were detected with MR angiography (n = 12) than with color Doppler US (n = 3; P <.05). For assessing all stenoses, the sensitivity and accuracy were 94% and 91%, respectively, for MR angiography and 71% and 76%, respectively, for US (P <.05). The sensitivity was higher for MR angiography (100%) than for US (79%; P <.05) in diagnosing stenoses with at least 50% narrowing. The specificity, accuracy, and negative predictive value in diagnosing stenoses of at least 50% narrowing were 93%, 95%, and 100% for MR angiography and 93%, 89%, and 90% for US. CONCLUSION: Breath-hold, gadolinium-enhanced MR angiography is superior to color Doppler US in accessory renal artery detection. Although the specificity of MR angiography is similar to that of color Doppler US, MR angiography has a better sensitivity and negative predictive value in depicting renal arterial stenoses.

Renal artery stenosis: evaluation with breath-hold, three-dimensional, dynamic, gadolinium-enhanced versus three-dimensional, phase-contrast MR angiography.

PURPOSE: To compare breath-hold, three-dimensional, gadolinium-enhanced magnetic resonance (MR) angiography with three-dimensional, phase-contrast MR angiography in the evaluation of renal artery stenosis. MATERIALS AND METHODS: Fifty-five consecutive adult patients with clinical suspicion of renovascular disease were prospectively examined with three-dimensional, phase-contrast MR angiography and breath-hold, three-dimensional MR angiography with injection of a standard dose of gadopentetate dimeglumine to evaluate the number of renal arteries and the presence and degree of stenosis. The standard of reference was intraarterial digital subtraction angiography. RESULTS: Gadolinium-enhanced MR angiography depicted all 105 main renal arteries, whereas phase-contrast MR angiography depicted 104. The number of accessory renal arteries depicted was significantly higher with gadolinium-enhanced (17 of 18) than with phase-contrast (11 of 18) studies (P = .04). Both techniques depicted 27 of the 29 stenoses (sensitivity, 93%; P > .05). Sensitivities, specificities, and accuracies in the diagnosis of hemodynamically significant stenosis (> 50% narrowing) were, respectively, 94%, 96%, and 96% for phase-contrast and 100%, 97%, and 98% for gadolinium-enhanced MR angiography (P > .05). CONCLUSION: Gadolinium-enhanced MR angiography is superior to phase-contrast MR angiography in accessory renal artery depiction. No statistically significant difference in the assessment of stenosis has been found between the two techniques.

Bioelectrical impedance in the evaluation of the nutritional status of hemodialyzed diabetic patients.

Bioelectrical impedance is a technique allowing a quick, repeatable and reliable assessment of body composition. This method was applied to detect total body water (TBW), fat (FAT) and fat-free mass (FFM) in 80 normal subjects, 65 diabetic (45 insulin-dependent [IDD], 20 non insulin-dependent [NIDD]) and 34 uremic diabetic patients (20 IDD, 14 NIDD) submitted to hemodialysis three times a week. Uremic patients were tested at the end of the dialytic session. Multivariated analysis adjusted for age, sex and disease showed the following results: body mass index (BMI) increased with age (p < 0.005) and in the presence of NIDD (p < .001); TBW was lower in nephropathic patients (p < 0.05) and in the female sex (p < 0.0001); FFM decreased with age (p < 0.005), female sex (p < 0.0001) and in nonuremic NIDD (p < 0.001). Correspondingly FAT increased with age (p < 0.005), female sex (p < 0.0001) and in nonuremic NIDD (p < 0.001). Sixteen uremic subjects, randomly selected from both IDD and NIDD groups, tested at the beginning and at the end of the same hemodialytic session, showed a significant decrease of TBW which corresponded to the correction of their overhydratation. In our patients uremia does not seem to influence the nutritional status and the bioelectrical analysis could be applied to determine the real dry weight in hemodialyzed diabetic patients.

[Vascular access for chronic hemodialysis in diabetic patients]. / Accessi vascolari per emodialisi cronica in pazienti diabetici.

The aim of this study carried out on 33 uremic diabetic patients submitted to chronic hemodialytic treatment was to assess the kind of complications related to the vascular approach used as well as their short- and long-term incidences. Out of the 46 anastomoses prepared, 39 were arteriovenous fistulae according to Brescia-Cimino and 7 were PTFE grafts. The actuarial survival rate was 88%, 79%, and 63% after one, two and four years, respectively. The most frequent compliance was thrombosis. Our experience demonstrates that the distal arteriovenous fistula may be considered a valid vascular access for hemodialysis also in diabetic patients.

Intermediary metabolism and glycemic control in insulin-dependent diabetic uremic patients treated by continuous peritoneal dialysis.

The effect on metabolic control and on intermediate metabolism of continuous ambulatory peritoneal dialysis (CAPD) was evaluated in 6 insulin-dependent diabetic uremic patients treated by CAPD, in 6 nondiabetic uremic patients in CAPD and in 6 normal subjects. During the study, 4 dialysis exchanges with 1.36 g/dl dextrose concentration were performed daily; regular insulin was added to the bags in diabetic patients. Our data show a well-controlled mean blood glucose in CAPD diabetic patients by intraperitoneal insulin administration as well as higher insulinemic levels in comparison with those of normal subjects. Plasma lactate and serum glycerol levels were higher and butyrate levels were lower reflecting a continuous ketogenesis inhibition.