In situ evaluation of the impact of metformin or verapamil coadministration with vildagliptin on its regional absorption from the rabbit's intestine

This research aims to identify regional differences in vildagliptin absorption across the intestinal membrane. Furthermore, it was to investigate the effect of verapamil or metformin on vildagliptin absorptive clearance. The study utilized an in situ rabbit intestinal perfusion technique to determine vildagliptin oral absorption from duodenum, jejunum, ileum, and ascending colon. This was conducted both with and without perfusion of metformin or verapamil. The findings revealed that the vildagliptin absorptive clearance per unit length varied by site and was in the order as follows: ileum < jejunum < duodenum < ascending colon, implying that P-gp is significant in the reduction of vildagliptin absorption. Also, the arrangement cannot reverse intestinal P-gp, but the observations suggest that P-gp is significant in reducing vildagliptin absorption. Verapamil co-perfusion significantly increased the vildagliptin absorptive clearance by 2.4 and 3.2 fold through the jejunum and ileum, respectively. Metformin co-administration showed a non-significant decrease in vildagliptin absorptive clearance through all tested segments. Vildagliptin absorption was site-dependent and may be related to the intestinal P-glycoprotein content. This may aid in understanding the important elements that influence vildagliptin absorption, besides drug-drug interactions that can occur in type 2 diabetic patients taking vildagliptin in conjunction with other drugs that can modify the P-glycoprotein level.

Randomized trial to assess the potential role of ascorbic acid and statin for post-contrast acute kidney injury prevention

PURPOSE

To evaluate the effect of using statins and ascorbic acid for the prevention of post-contrast acute kidney injury (PC-AKI) in patients undergoing urologic diagnostic elective contrast-enhanced computed tomography (CECT).

METHODS

This registered trial (NCT03391830) was for statin naïve patients underwent elective CECT. Patients were randomized allocated to two groups: the first group received atorvastatin 80-mg the day before the study and atorvastatin 40-mg two hours before the CECT and for continue on atorvastatin 40-mg two days after CECT; plus ascorbic acid 500 mg with atorvastatin. The other group received two tablets of placebo once/daily before the procedure and for another 3 days. The primary outcome was to assess the incidence PC-AKI.

RESULTS

The baseline parameters were comparable between both groups. The final median (interquartile range "IQR") serum creatinine were 0.80 (0.60, 1.00) and 0.80 (0.60, 1.00), respectively, with insignificant p-value (p = 0.8). The median (IQR) final estimated GFR were 95.2 (72.8, 108.1) and 88.6 (71.9, 111.0) mL/min in placebo and statin plus ascorbic acid groups, respectively (p = 0.48). The eGFR difference median (IQR) were - 6.46 (- 11.72, - 4.18) and - 6.57 (- 13.38, - 3.82) ml/min in placebo and statin plus ascorbic acid groups, respectively (p = 0.58). PC-AKI occurred in 11 patients (9.8%) in placebo group and in 3 patients (3%) in statin plus ascorbic acid group (p = 0.04).

CONCLUSIONS

Statin and ascorbic acid did not statistically improve neither serum creatinine nor eGFR values in patient underwent CECT. However, it can decrease the incidence of the clinically insignificant PC-AKI.

Supranormal differential renal function in adults with ureteropelvic junction obstruction: Does it really exist?

Introduction

Some patients with ureteropelvic junction obstruction (UPJO) have supranormal differential renal function (snDRF). We aimed to study the outcomes of pyeloplasty in adult patients with UPJO and either snDRF or normal differential renal function (nDRF) and to identify preoperative factors responsible for the snDRF phenomenon.

Materials and Methods

We retrospectively retrieved data for all patients who underwent pyeloplasty and had snDRF (differential renal function [DRF] ≥55%) and nDRF (DRF between 45 and 55%) preoperatively. Preoperative radiological data using computed tomography or magnetic resonance imaging were correlated with the presence of snDRF phenomenon. In addition, scintigraphic findings pre- and post-operatively were also assessed to evaluate the functional outcomes.

Results

Of a total of 856 patients, 31 had snDRF (group 1) and 42 had nDRF (group 2). After a mean of 37 months' follow-up in Group 1, 22 patients developed DRF reduction with non-obstructive pattern. Mean DRF % decreased from 59 ± 2.8 to 48 ± 13 (P < 0.0001). However, in Group 2, five patients had DRF decrease. Four patients developed snDRF phenomenon postoperatively. Increased renal pelvis volume ≥50 mm³ and increased anteroposterior pelvic diameter (APD) ≥37 mm were found to predict snDRF phenomenon. The same findings, in addition to preoperative snDRF, correlated with postoperative DRF decrease.

Conclusion

SnDRF function could be expected in patients with increased renal pelvis volume and APD. The absolute value or changes in DRF are not reliable to judge treatment failure.