Relative Bioavailability of Silybin A and Silybin B From 2 Multiconstituent Dietary Supplement Formulations Containing Milk Thistle Extract: A Single-dose Study.

PURPOSE: The purpose of this study was to compare the bioavailability between 2 milk thistle-containing dietary supplements, Product B and IsaGenesis, in healthy volunteers. METHODS: Bioavailability between Product B, originally formulated as a powdered capsule, and IsaGenesis, reformulated as a soft gel, were compared by measuring silybin A and silybin B as surrogate pharmacokinetic markers for differences in absorption and bioavailability. For this randomized, open-label, crossover pharmacokinetic study, 12 healthy volunteers consumed a single-dose serving of each supplement separated by at least a 7-day washout period. Serial blood samples were obtained at 0, 0.5, 1, 1.5, 2, 3, 4, 6, and 8 hours and analyzed via LC-MS/MS. FINDINGS: Rapid absorption and elimination of silybin A and silybin B have been observed after oral administration of both Product B and IsaGenesis. However, the absorption rate and extent, as indicated by mean the Cmax and mean plasma AUC, were significantly higher for the IsaGenesis soft gel formulation. The dose-corrected mean Cmax was 365% and 450% greater for silybin A and B, respectively, relative to powdered Product B. The time to Tmax was reached, on average, at least 1 hour earlier with IsaGenesis relative to Product B for both silybin A and silybin B. IMPLICATIONS: The IsaGenesis soft gel formulation provided substantially greater absorption and bioavailability of silybin A and silybin B relative to the powdered Product B supplement. ClinicalTrials.gov Identifier: NCT02529605.

Salvage of problematic peritoneal dialysis catheters.

Peritoneal dialysis (PD) is a markedly underutilized modality for permanent renal replacement therapy in the United States owing to a low rate of patient referral and high rate of patient dropout or transfer to hemodialysis. One cause for patient loss from PD is problematic PD catheters that often are removed rather than being subjected to simple surgical salvage procedures. We report three patients with problematic catheters and our approach to their management. The first patient developed erosion of the skin overlying the portion of the catheter between the deep and superficial cuffs after 6 months of PD. The second patient developed extrusion of the superficial cuff after 4 years of PD. The third patient demonstrated a localized abscess at the incision site for catheter insertion after 3 years of PD. Other than a mild superficial exit site infection and localized abscess in the second and third patient, respectively, there were no associated infections of the catheter tunnel and cuff or of the peritoneal cavity as determined by either clinical examination, ultrasound evidence of fluid collection, or cultures and white blood cell counts. All three cases were managed successfully by interventional nephrology on an outpatient basis and under local anesthesia without either catheter removal or placement of a new PD catheter. It was possible to continue uninterrupted PD in the first and third patients, while the second patient had temporary hemodialysis to allow for complete healing of the surgical wound. We conclude that in selected cases simple interventions can salvage problematic PD catheters and maintain patients on PD.

Nephrology nurses in a new role: diagnostic and interventional nephrology.

Diagnostic and interventional nephrology is a growing subspecialty of nephrology. Increasingly, procedural care of nephrology patients is being managed by nephrologists trained in this area. As a result, new opportunities have been created for nephrology nurses as they assist these interventionists in the administration of care in diagnostic and interventional nephrology. This article describes the components of a diagnostic and interventional nephrology program, the initiation of such a program at a university center, and the role of nephrology nursing personnel in this rapidly developing area.