Background and Objectives: Peritoneal dialysis (PD) is a renal replacement therapy modality in which the dialysis dose can be individually adapted according to the patients’ residual kidney function (RKF). RKF is a crucial factor for technique and patient survival. Pharmacological strategies aimed at slowing the loss of RKF in patients on PD are limited. Therefore, we aimed to assess the potential effects and safety of sodium–glucose cotransporter 2 (SGLT-2) inhibitors on the preservation of RKF in patients with and without type 2 diabetes mellitus (T2DM) on PD during an average follow-up of 6 months. Materials and Methods: In this retrospective observational, single-center study on real-world data, we included patients from the Peritoneal Dialysis Unit of the Hospital General Universitario de Ciudad Real, who started treatment with SGLT-2 inhibitors during the period from December 2022 to December 2023. Data on analytical and clinical parameters, RKF, and peritoneal membrane transport function were retrospectively collected at months 0, 3, and 6. Results: Out of 31 patients in our unit, 16 prevalent patients initiated treatment with SGLT-2 inhibitors (13 empagliflozin and 3 dapagliflozin). A total of 62.5% were male and the mean age was 67.3 years. The baseline peritoneal ultrafiltration was higher in the non-diabetic patient (NDMP) group than in the diabetic patient (DMP) group. However, the residual diuresis volume, 24 h residual renal clearance rate of urea in urine, and 24 h proteinuria were higher in the DMP group than in the NDMP group. At the sixth month, patients in both groups preserved RKF and diuresis, with a trend towards a non-significant reduction in proteinuria and blood pressure. Only two patients of the DMP group presented adverse effects. Conclusions: The use of SGLT-2 inhibitors in our sample of patients with and without T2DM on PD appears to be safe and effective to preserve RKF.

Background: Uremic tumoral calcinosis (UTC) is a rare yet severe complication of chronic kidney disease (CKD), predominantly occurring in patients undergoing renal replacement therapy (RRT). It is characterized by extensive soft tissue calcifications, frequently associated with chronic hyperphosphatemia and disruptions to calcium–phosphorus metabolism. Case report: This report describes a 34-year-old woman with end-stage renal disease (ESRD) secondary to lupus nephritis, undergoing continuous ambulatory peritoneal dialysis (CAPD). She presented with a progressively enlarging calcified mass in the proximal phalanx of the third finger on her right hand, accompanied by functional impairment. Laboratory findings revealed persistent hyperphosphatemia (8.8 mg/dL), elevated parathyroid hormone levels (901 pg/mL), and low vitamin D levels (9 ng/mL), indicating significant disturbances to mineral metabolism. Imaging studies, including X-ray and whole-body 18F-Choline positron emission tomography/computed tomography (PET/CT), confirmed the presence of localized calcifications in the soft tissue of the proximal phalanx of the third finger on her right hand and parathyroid hyperplasia, respectively. Initial management included the optimization of phosphate binders and calcimimetic therapy, with the subsequent intensification of dialysis therapy. Transitioning to automated peritoneal dialysis (APD) with high-volume exchanges resulted in a notable improvement in biochemical parameters and the eventual remission of the calcified mass. Conclusion: This case underscores the importance of comprehensive management in dialysis patients, including dietary phosphate restriction, the appropriate use of non-calcium-based binders, and tailored dialysis regimens to prevent and treat CKD-related mineral and bone disorders. It also highlights the utility of imaging modalities such as PET/CT in diagnosing UTC and monitoring response to therapy. Further research is needed to elucidate the pathophysiology of UTC and optimize its management in dialysis patients.