Assessment of the Hemodynamics of Autogenous Arteriovenous Fistulas With 4D Phase Contrast-Based Flow Quantification MRI in Dialysis Patients.

BACKGROUND: Regular monitoring of autogenous arteriovenous fistulas (AVFs) for hemodialysis patients has importance. Hence, 4D flow MRI may be an alternative for assessing the hemodynamics of AVFs. PURPOSE: To compare the hemodynamics of AVFs using Doppler ultrasound (DUS) and 4D-MRI in renal dialysis patients. STUDY TYPE: Case-control study from October 2017 to April 2018. POPULATION: Fifty patients (age [range] = 59.52 [39-71] years) with AVFs were included. FIELD STRENGTH/SEQUENCE: Black-blood MRI and 4D flow MRI at 3.0T and AVF ultrasonography were also performed. ASSESSMENT: The hemodynamics acquired from 4D flow MRI and ultrasonography by two radiologists were compared. The AVF anatomy was described through an examination of the black-blood MRI. STATISTICAL TESTS: The consistency of AVF anatomy and hemodynamics and the consistency of the hemodynamics of AVFs from 4D flow MRI and ultrasound were analyzed by paired t-tests. The morphological parameters of AVFs acquired from black-blood MRI were used for a Pearson correlation analysis with the hemodynamic parameters obtained from 4D flow MRI data. RESULTS: The consistency of the morphological and hemodynamic parameters measured from MRI by the two radiologists was good (all P < 0.01). The velocities and flow volumes from the 4D flow MRI and vascular ultrasound of AVFs were in moderate agreement (all P < 0.05, r = 0.292-0.569), except for the peak flow velocity at the anastomosis (P = 0.366, r = -0.078). The flow volume and WSS near the anastomotic site were closely related to the morphology of the AVFs (all P < 0.05). The hemodynamics of the complications group were significantly different from those of patients without any complications (normal patients group) (all P < 0.01). DATA CONCLUSION: Compared with ultrasonography, 4D flow MRI is a promising technique to noninvasively estimate the AVF hemodynamics of renal dialysis patients. LEVEL OF EVIDENCE: 3 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2020;51:1272-1280.

Iron metabolism in infants: influence of bovine lactoferrin from iron-fortified formula.

OBJECTIVE: The aim of this study was to evaluate whether an iron-fortified formula with a concentration of lactoferrin would significantly improve the hematologic indexes and iron status in term infants compared with those same values in infants fed an iron-fortified formula without lactoferrin. METHOD: In this prospective, multicenter, controlled intervention study, 260 infants ages 4 to 6 mo were selected from six maternal and children's health care hospitals in the area. All infants were divided into two groups with the sequence of outpatient: lactoferrin-fortified formula milk group (fortified group, FG, containing lactoferrin 38 mg/100 g milk and iron element 4 mg/100 g milk) and no lactoferrin fortified milk (control group, CG, containing lactoferrin 0 mg/100 g milk and iron element 4 mg/100 g milk) for 3 mo. The levels of weight, height, and head circumference and the concentration of hemoglobin (Hb), serum ferritin (SF), and serum transferring receptor (sTfR) were measured and sTfR-SF index (TFR-F index), total body iron content (TBIC) and low height for age (HAZ), low weight for age (WAZ), and low weight for height (WHZ) were computed before and after the intervention, respectively. RESULTS: In all, 213 (115 in FG and 98 in CG) infants completed the intervention trial and all measurements of biochemical indicators. There were no significant differences in the average amount of daily intake of formula milk (94.3 ± 9.8 g versus 88.2 ± 8.7 g for FG and CG; P > 0.05) and iron element (3.8 ± 0.4 mg versus 3.7 ± 0.6 mg for FG and CG; P > 0.05). The average amount of daily intake of lactoferrin for infants in FG group was 35.8 ± 3.7 mg. The levels of weight, WAZ, WHZ, Hb, SF, TFR-F index, and TBIC after intervention of infants in FG were all significantly higher than those of infants in CG weight, 8723 ± 245 g versus 8558 ± 214g; WAZ, 1.02 ± 0.31 versus 0.44 ± 0.18; WHZ, 0.98 ± 0.31 versus 0.41 ± 0.12; Hb, 125.5 ± 15.4 g/L versus 116.9 ± 13.1 g/L; SF, 44.7 ± 17.2 µg/L versus 31.6 ± 18.4 µg/L; TFR-F index, 1.88 ± 0.41 versus 1.26 ± 0.39; TBIC, 6.12 ± 0.78 mg/kg versus 5.26 ± 0.55 mg/kg for FG and CG; P < 0.05), but significantly lower (P < 0.05) for the prevalence of anemia (4.1% versus 7.5%), iron deficiency (13.9% versus 24.4%), and iron-deficient anemia (1.7% versus 6.1%). CONCLUSION: When infants who were exclusively breastfed were supplemented with lactoferrin-fortified milk, significant increases in TBIC and iron absorption in the intestine were seen.