Background.: The efficacy and safety of sodium-glucose cotransporter 2 inhibitors (SGLT2i) have not been investigated in kidney transplant recipients (KTRs) with diabetes. We evaluated the impact of SGLT2i in a multicenter cohort of diabetic KTRs. Methods.: A total of 2083 KTRs with diabetes were enrolled from 6 transplant centers in Korea. Among them, 226 (10.8%) patients were prescribed SGLT2i for >90 d. The primary outcome was a composite outcome of all-cause mortality, death-censored graft failure (DCGF), and serum creatinine doubling. An acute dip in estimated glomerular filtration rate (eGFR) over 10% was surveyed after SGLT2i use. Results.: During the mean follow-up of 62.9 ± 42.2 mo, the SGLT2i group had a lower risk of primary composite outcome than the control group in the multivariate and propensity score-matched models (adjusted hazard ratio, 0.43; 95% confidence interval, 0.24-0.78; P = 0.006 and adjusted hazard ratio, 0.45; 95% confidence interval, 0.24-0.85; P = 0.013, respectively). Multivariate analyses consistently showed a decreased risk of DCGF and serum creatinine doubling in the SGLT2i group. The overall eGFR remained stable without the initial dip after SGLT2i use. A minority (15.6%) of the SGLT2i users showed acute eGFR dip during the first month, but the eGFR recovered thereafter. The risk factors for the eGFR dip were time from transplantation to SGLT2i usage and mean tacrolimus trough level. Conclusions.: SGLT2i improved a composite of all-cause mortality, DCGF, or serum creatinine doubling in KTRs. SGLT2i can be used safely and have beneficial effects on preserving graft function in diabetic KTRs.

The outcome of coronavirus disease 2019 (COVID-19) is associated with organ damage; however, the information about the relationship between acute kidney injury (AKI) and COVID-19 is still rare. We evaluated the clinical features and prognosis of COVID-19 patients with AKI according to the AKI severity. Medical data of hospitalized COVID-19 patients in two university-based hospitals during an outbreak in Daegu, South Korea, were retrospectively analyzed. AKI and its severity were defined according to the Acute Kidney Injury Network. Of the 164 hospitalized patients with COVID-19, 30 patients (18.3%) had AKI; 14, 4, and 12 patients had stage 1, 2, and 3, respectively. The median age was significantly higher in AKI patients than in non-AKI patients (75.5 vs. 67.0 years, p = 0.005). There were 17 deaths (56.7%) among AKI patients; 4 (28.6%), 1 (25.0%), and 12 (100.0%), respectively. In-hospital mortality was higher in AKI patients than in non-AKI patients (56.7% vs. 20.8%, p < 0.001). After adjusting for potential confounding factors, stage 3 AKI was associated with higher mortality than either non-AKI or stage 1 AKI (hazard ratio (HR) = 3.62 (95% confidence interval (CI) = 1.75–7.48), p = 0.001; HR = 15.65 (95% CI = 2.43–100.64), p = 0.004). Among the AKI patients, acute respiratory distress syndrome and low serum albumin on admission were considered independent risk factors for stage 3 AKI (both p < 0.05). Five patients with stage 3 AKI underwent dialysis and eventually died. In conclusion, COVID-19 patients with severe AKI had fatal outcomes.

Medium cut-off (MCO) dialyzers help remove larger middle molecules associated with symptoms related to the accumulation of uremic retention solutes. We investigated the effect of an MCO dialyzer on the improvement of quality of life (QOL) in maintenance hemodialysis (HD) patients. Forty-nine HD patients with high-flux dialysis were randomly assigned to either an MCO (Theranova 400, Baxter) or a high-flux (FX CorDiax 80 or 60, Fresenius Medical Care) dialyzer and completed the study. QOL was assessed at baseline and after 12 weeks of treatment using the Kidney Disease Quality of Life Short Form-36, and pruritus was assessed using a questionnaire and visual analog scale. The reduction ratios of middle molecules were also evaluated. Laboratory markers, including serum albumin, did not differ between the two groups after 12 weeks. Removals of kappa and lambda free light chains were greater for MCO dialyzer than high-flux dialyzer. The MCO group had higher scores than the high-flux group in the domains of physical functioning and physical role (75.2 ± 20.8 vs. 59.8 ± 30.1, P = 0.042; 61.5 ± 37.6 vs. 39.0 ± 39.6, P = 0.047, respectively), and the MCO group had lower mean scores for morning pruritus distribution and the frequency of scratching during sleep (1.29 ± 0.46 vs. 1.64 ± 0.64, P = 0.034; 0.25 ± 0.53 vs. 1.00 ± 1.47, P = 0.023, respectively). MCO dialyzers may improve patient-reported outcomes, particularly the physical components of QOL and uremic pruritus, in patients with high-flux dialyzers.

Significance Statement: Health care–associated infections during previous serious coronavirus epidemics resulted from human-to-human transmission in hemodialysis (HD) facilities. The authors analyzed the effect of a strategy of HD with cohort isolation on the secondary transmission of coronavirus disease 2019 (COVID-19) in HD facilities in Korea, which involves administering an immediate screening test for COVID-19 to all close contacts (patients on HD and health care workers) and strict maintenance of cohort isolation. Epidemiologic investigation and immediate screening tests across 11 HD centers identified 302 close contacts. HD with cohort isolation was maintained for a median of 14 days, and the transmission rate was 0.66% inside HD units. Clinical practice guidelines for HD with cohort isolation during COVID-19 outbreaks may successfully prevent secondary transmission through HD units. Background: Health care–associated infections during previous coronavirus epidemics involving severe acute respiratory syndrome and Middle East respiratory syndrome resulted from human-to-human transmission in hemodialysis (HD) facilities. The effect of a strategy of HD with cohort isolation—separate dialysis sessions for close contacts of patients with confirmed coronavirus disease 2019 (COVID-19)—on the prevention of secondary transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in HD units is unknown. Methods: Our multicenter cohort study of an HD with cohort isolation strategy enrolled close contacts of patients with confirmed COVID-19, including patients on HD and health care workers in HD units. Close contacts had been identified by epidemiologic investigation and tested negative on an immediate screening test for SARS-CoV-2. Results: As of March 14, 11 patients on HD and 7 health care workers from 11 HD centers were diagnosed as having COVID-19. The immediate screening test was performed in 306 people, and among them, 302 close contacts with negative test results were enrolled. HD with cohort isolation was performed among all close contacts for a median of 14 days in seven centers. During cohort isolation, nine patients showed symptoms but tested negative for SARS-CoV-2. Two health care workers in the HD units (0.66% of the total group) were diagnosed at the termination test for SARS-CoV-2. Conclusions: The transmission of COVID-19 can be controlled without closure of HD centers by implementing preemptive activities, including early detection with rapid testing, cohort isolation, collaboration between institutions, and continuous monitoring of infection. Our strategy and experience may provide helpful guidance for circumstances involving the rapid spread of infectious diseases such as COVID-19.

Lim JH, et al. J Korean Med Sci. 2021 Jul;36(30):e218. https://doi.org/10.3346/jkms.2021.36.e218

The protective effects of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX) 1 inhibition against kidney ischemia-reperfusion injury (IRI) remain uncertain. The bilateral kidney pedicles of C57BL/6 mice were clamped for 30 min to induce IRI. Madin–Darby Canine Kidney (MDCK) cells were incubated with H₂O₂ (1.4 mM) for 1 h to induce oxidative stress. ML171, a selective NOX1 inhibitor, and siRNA against NOX1 were treated to inhibit NOX1. NOX expression, oxidative stress, apoptosis assay, and mitogen-activated protein kinase (MAPK) pathway were evaluated. The kidney function deteriorated and the production of reactive oxygen species (ROS), including intracellular H₂O₂ production, increased due to IRI, whereas IRI-mediated kidney dysfunction and ROS generation were significantly attenuated by ML171. H₂O₂ evoked the changes in oxidative stress enzymes such as SOD2 and GPX in MDCK cells, which was mitigated by ML171. Treatment with ML171 and transfection with siRNA against NOX1 decreased the upregulation of NOX1 and NOX4 induced by H₂O₂ in MDCK cells. ML171 decreased caspase-3 activity, the Bcl-2/Bax ratio, and TUNEL-positive tubule cells in IRI mice and H₂O₂-treated MDCK cells. Among the MAPK pathways, ML171 affected ERK signaling by ERK phosphorylation in kidney tissues and tubular cells. NOX1-selective inhibition attenuated kidney IRI via inhibition of ROS-mediated ERK signaling.