Wood Cell Wall Nanoengineering toward Anisotropic, Strong, and Flexible Cellulosic Hydrogel Sensors.

Achieving highly ionic conductive hydrogels from natural wood remains challenging owing to their insufficient surface area and low number of active sites on the cell wall. This study proposes a viable strategy to design a strong and anisotropic wood-based hydrogel through cell wall nanoengineering. By manipulating the microstructure of the wood cell wall, a flexible cellulosic hydrogel is achieved through Schiff base bonding via the polyacrylamide and cellulose molecular chains. This results in excellent flexibility and mechanical properties of the wood hydrogel with tensile strengths of 22.3 and 6.1 MPa in the longitudinal and transverse directions, respectively. Moreover, confining aqueous salt electrolytes within the porous structure gives anisotropic ionic conductivities (19.5 and 6.02 S/m in the longitudinal and transverse directions, respectively). The wood-based hydrogel sensor has a favorable sensitivity and a stable working performance at a low temperature of -25 °C in monitoring human motions, thereby demonstrating great potential applications in wearable sensor devices.

Post-transplant idiopathic immune complex membrano-proliferative glomerulonephritis: Characteristics and outcomes.

BACKGROUND: There is little published information on the natural history and the treatment of immune complex membrano-proliferative glomerulonephritis (IC-MPGN) of unknown cause in the transplanted kidney. MATERIALS AND METHODS: From 01/2004 to 12/2018, 41 patients had the diagnosis of post-transplant idiopathic IC-MPGN and were included in the study. RESULTS: The mean age of the cohort at the time of transplant was 50 ± 13 years. The most common presentation was increased proteinuria, followed by kidney dysfunction. Fewer than 50% of patients had hematuria at presentation. 25 patients (61%) had no change in their baseline immunosuppression after the diagnosis of idiopathic IC-MPGN. Eight patients (19.5%) received steroids alone, and 8 patients (19.5%) received rituximab with (7) or without (1) steroids. The patients who received rituximab had better uncensored graft survival than the patients who received no treatment (p = 0.02), but the benefit of steroids compared to no treatment did not reach statistical significance (p = 0.05). The multivariate analysis retained eGFR < 30 mL/min/1.73m2 at time of diagnosis (HR = 3.30, p = 0.02; 95% Cl 1.15 - 9.46) as a significant predictor of graft loss. In this analysis, treatment of idiopathic IC-MPGN was associated with lower graft loss (HR = 0.22, p = 0.02; 95% Cl 0.06 - 0.78). CONCLUSION: To the best of our knowledge, this is the largest clinic-pathological series of post-transplant idiopathic IC-MPGN. Treatment of idiopathic IC-MPGN may be associated with better graft outcomes.

Sustainable approaches towards green synthesis of TiO2 nanomaterials and their applications in photocatalysis-mediated sensing to monitor environmental pollution.

Nanomaterials are gaining enormous interests due to their novel applications that have been explored nearly in every field of our contemporary society. In this scenario, preparations of nanomaterials following green routes have attracted widespread attention in terms of sustainable, reliable, and environmentally friendly practices to produce diverse nanostructures. In this review, we summarize the fundamental processes and mechanisms of green synthesis approaches of TiO2 nanoparticles (NPs). We explore the role of plants and microbes as natural bioresources to prepare TiO2 NPs. Particularly, focus has been made to explore the potential of TiO2 -based nanomaterials to design a variety of sensing platforms by exploiting the photocatalysis efficiency under the influence of a light source. These types of sensing are of massive importance for monitoring environmental pollution and therefore for inventing advanced strategies to remediate hazardous pollutants and offer a clean environment.

Regional citrate and systemic heparin are adequate to maintain filter half-life for COVID-19 patients on continuous renal replacement therapy.

INTRODUCTION: The aim of our study is to compare clotting of CRRT filters in patients with COVID-19-associated AKI versus septic shock-associated AKI. METHODS: Retrospective study of adult ICU patients with COVID-19 compared to those with septic shock admitted to a tertiary hospital April-October 2020. Independent t test and chi-square test used to determine statistical significance of CRRT filter clotting between the two groups. Time-to-event data analyzed with Kaplan-Meier curves. Analyses performed on Microsoft Excel and MedCalc. RESULTS: Twenty-seven ICU patients with AKI requiring CRRT were included, 13 with COVID-19 and 14 non-COVID-19 patients with septic shock. The mean half-life of CRRT hemofilter was similar in COVID-19 patients compared to non-COVID-19 patients (27.4 vs. 27.5 h, p = 0.79). The number of CRRT hemofilter changes per day was similar in both groups (0.6 filter changes per day, p = 0.84). However, significantly more patients with COVID-19 were on systemic heparin (69% vs. 13%, p = 0.02). CONCLUSION: We found that COVID-19 patients with AKI requiring CRRT had similar CRRT hemofilter half-life compared with sepsis-associated AKI patients with use of regional citrate and systemic heparin. Further studies are needed to find which methods of anticoagulation are optimal in patients with COVID-19 infection with AKI requiring CRRT.

Home call during nephrology fellowship: Burden or benefit?

BACKGROUND: Home call is one of the factors that can influence physician wellness. Nephrology fellows at the University of Wisconsin tracked home call activities in an attempt to quantify the impact of sleep to identify areas for improvement. MATERIALS AND METHODS: Each of the 6 nephrology fellows filled out a daily survey between November 9, 2020, and January 31, 2021, to address total hours, quality of sleep, and if the fellows reported to the hospital. RESULTS: The average amount of sleep per night was 5.3 hours. When necessary to report to the hospital (50%), the average hours of sleep dropped to 4.3 hours. However, if not called in, sleep increased to 5.8 hours per night. Sleep quality during night call was described as restful for 55% of nights. CONCLUSION: Obtaining an understanding of how a call can impact a learner is essential to making decisions about programmatic structural changes. Programs might use this data to compare their programs when making decisions about call structure. Hospital culture or overnight management changes can be made to impact the number of phone calls or needs to report to the hospital.

Use of CRRT and Plasmapheresis to Treat Simultaneous Iron and Acetaminophen Overdose.

There is limited information about the prevalence and treatment of concurrent acetaminophen and iron overdose. One case study has suggested that this combination may be lethal. We present a case of fatal intentional acetaminophen and iron overdose and treatment with extracorporeal methods, including continuous venovenous hemofiltration and plasmapheresis, for removal of both toxins.

Long-term outcomes in kidney transplant recipients with end-stage kidney disease due to anti-glomerular basement membrane disease.

Anti-glomerular basement membrane (GBM) disease causes rapidly progressive glomerulonephritis and end-stage kidney disease (ESKD). Studies of post-transplant outcomes in patients with ESKD due to anti-GBM disease in the United States are lacking. To better characterize outcomes of transplant recipients with a history of anti-GBM disease, we examined patient survival and graft survival among recipients with anti-GBM disease compared with IgA nephropathy at a single center in the United States. We analyzed patient survival, graft survival, disease recurrence, and malignancy rates for kidney transplant recipients with ESKD due to biopsy-proven anti-GBM disease who underwent kidney transplantation at our center between 1994 and 2015. 26 patients with biopsy-proven anti-GBM disease and 314 patients with IgAN underwent kidney transplantation from 1994 to 2015. The incidence of graft loss was 6.2 per 100 person-years for anti-GBM disease, which was similar to IgAN (4.08 per 100 person-years, p = .09). Patient mortality for anti-GBM was 0.03 per 100 person-years, similar to IgAN (0.02 per 100 person-years, p = .12). Disease recurrence occurred in one of the 26 anti-GBM patients. Four out of 26 patients (15%) developed malignancy, most commonly skin cancer. Long-term graft and patient survival for patients with ESKD due to anti-GBM was similar to IgAN after kidney transplantation.

Post-kidney transplant serum magnesium exhibits a U-shaped association with subsequent mortality: an observational cohort study.

Hypomagnesemia is common in kidney transplant recipients (KTRs). We sought to explore the relationship between Mg and outcomes in KTRs, which may be associated with mortality and thus may be a potential intervention target to improve outcomes. We followed KTRs performed between 01/2000 and 6/2016 at a large US transplant center from 6 months post-transplant to graft failure, death, or loss to follow-up. Using Mg as a time-dependent variable, associations between Mg and outcomes any time after 6 months post-transplant were evaluated. 3680 KTRs with 50  413 Mg measurements met inclusion criteria. 657 deaths occurred over a median follow-up of 5.1 years. Compared to Mg of 1.5-1.8 mg/dl, both lower (HR 1.17, 95% confidence interval (CI): 1.07-1.28) and higher (HR 1.16, 95% CI: 1.09-1.23) Mg levels were associated with greater risk of mortality. Similar U-shaped associations were observed for Mg and cardiovascular disease-related mortality (HR for Mg ≤1.5 mg/dl: 1.31; CI: 1.03-1.68) and infection-related mortality (HR for Mg ≤1.5 mg/dl: 1.28; CI: 1.09-1.51), although relationships for Mg >1.8 mg/dl were not statistically significant. Mg exhibits a U-shaped association with mortality in KTRs, with levels between 1.5 and 1.8 mg/dl associated with the lowest risk.

Penicillium rotoruae, a new Species from an In-Ground Timber Durability Test Site in New Zealand.

A Penicillium species isolated during a 1960s study on the ecology of fungi infecting Pinus radiata timber, and subsequently held in an in-house collection in Rotorua, New Zealand, was found to differ morphologically and in growth rate from two closely related Penicillium species. Phylogenetic analysis of the rDNA internal transcribed spacer (ITS), ß-tubulin, calmodulin and RNA polymerase II second largest subunit regions (RPB2) confirmed this to be a new species closely related to Penicillium ochrochloron in the Rolfsiorum series of the Lanata-Divaricata section and Aspergilloides sub-genus. Micromorphologically, the new species is characterised by predominantly monoverticilliate and occasional divaricate or biverticilliate conidiophores and smooth-walled subglobose to slightly ovoid conidia with absence of conidiogenesis at 25 °C. This new species is described here as Penicillium rotoruae sp. nov. which has potential applications in biofuel and biorefining industry.

Metabolic Acidosis 1 Year Following Kidney Transplantation and Subsequent Cardiovascular Events and Mortality: An Observational Cohort Study.

RATIONALE & OBJECTIVE: Recent studies suggest that metabolic acidosis is associated with mortality and graft failure in kidney transplant recipients. However, it is unknown whether serum bicarbonate (measured as total carbon dioxide [tCO2] in serum) levels predict cardiovascular events (CVEs) following kidney transplantation. STUDY DESIGN: Observational cohort study. SETTINGS & PARTICIPANTS: Single-center study of 2,128 kidney transplant recipients free of CVEs during the first 13.5 months following transplantation. PREDICTOR: tCO2 level at 1 year posttransplantation. OUTCOMES: Ischemic, arrhythmic, and heart failure CVEs and death from any cause. ANALYTICAL APPROACH: Independent associations were assessed using multivariable proportional hazards regression models. Restricted cubic spline Poisson models were used to explore nonlinear associations. Linear spline proportional hazards models were used to assess associations at different tCO2 levels. RESULTS: The prevalence of metabolic acidosis defined as tCO2 level < 24 mEq/L was 38.8% (n=826). There were 384 recipients with a CVE and 610 deaths during a median follow-up of 4.0 years. CVEs included 241 ischemic, 137 arrhythmic, and 150 heart failure events. tCO2 level < 20 mEq/L was associated with increased risk for CVEs (adjusted HR [aHR], 2.00; 95% CI, 1.29-3.10) compared to the reference category of tCO2 level of 24.0 to 25.9 mEq/L. This association was primarily due to ischemic CVEs (aHR, 2.28; 95% CI, 1.34-3.90). For every 1 mEq/L lower tCO2 level for those with tCO2 < 24 mEq/L, risks for all CVEs and ischemic events were 17% and 15% higher, respectively (aHR for all CVEs of 0.83 [95% CI, 0.74-0.94] and aHR for ischemic CVEs of 0.85 [95% CI, 0.74-0.99]). Notably, tCO2 level < 20 mEq/L, compared to tCO2 level of 24.0 to 25.9 mEq/L, was independently associated with all-cause mortality (aHR, 1.43; 95% CI, 1.02-2.02). For every 1-mEq/L lower tCO2 level for those with tCO2 < 24 mEq/L, there was 17% higher risk for death (aHR, 0.83; 95% CI, 0.75-0.92). LIMITATIONS: Single-center observational study. CONCLUSIONS: Metabolic acidosis is an independent risk factor for ischemic CVEs after kidney transplantation. It is unknown whether correction of acidosis improves outcomes in these patients.

The association of acute rejection vs recurrent glomerular disease with graft outcomes after kidney transplantation.

BACKGROUND: It has been shown that glomerulonephritis (GN) recurrence affects graft survival more than acute rejection. Thus, we assessed allograft survival after biopsy-confirmed diagnosis of acute rejection or recurrent GN in current era of immunosuppression. METHODS: Allograft survival following a biopsy diagnosis of acute rejection or recurrent GN was determined in adult kidney transplant recipients from 1994 to 2013. A total of 306 patients (35%) with IgA, 298 (35%) with FSGS, 177 (21%) with lupus nephritis, and 81 (9%) with membranous nephropathy were followed for a median of 6.3 years. RESULTS: Among the 862 transplant recipients with primary GN, allograft loss was similar following a biopsy diagnosis of acute rejection or recurrent glomerular disease (11.5 vs 14.2/100 person-years, P = .15). Differences in allograft survival emerged after 2.5 years following recurrent disease, with significantly higher graft failure in patients with FSGS, MN, or LN compared with IgA after recurrence of disease (16.7 vs 7.5/100 person-years, P = .05). The advantage in allograft survival for IgA patients did not achieve significance after acute rejection (P = .10 for IgA vs FSGS, MN, and LN). CONCLUSIONS: Allograft survival was similar after disease recurrence or acute rejection after kidney transplant in patients with ESRD due to GN.

Outcomes of Norovirus diarrheal infections and Clostridioides difficile infections in kidney transplant recipients: A single-center retrospective study.

Recently, Norovirus has been recognized as an important cause of diarrheal infection in kidney transplant recipients (KTRs). We assessed the risk factors and outcomes of Norovirus diarrheal infections (NVDI) and Clostridioides difficile infection (CDI) on graft and patient survival following kidney transplant (KT). We examined KTRs transplanted at our center between 1994 and 2014, and compared those who suffered from NVDI and CDI with patients who did not develop either infection. Each patient with NVDI or CDI was matched with five controls based on time from transplant. Of the 4941 KTs performed during the study period, there were 2112 evaluable cases: 66 NVDI cases, 286 CDI cases, and 1760 controls. Median uncensored graft survival following infection was 497.5 days for the NVDI group, 440 days for the CDI group, and 1271 days for controls. Those with CDI had significantly inferior graft survival than controls (HR 2.41; CI 2.01, 2.90; P < 0.001), and those with NVDI had a 23% lower risk of graft survival than controls (HR 1.23; CI 1.0, 1.52; P = 0.054). Diarrheal infection after KT is associated with reduced long-term graft survival.

Improvement in Hyperphosphatemia Using Phosphate Education and Planning Talks.

OBJECTIVE: Hyperphosphatemia is a common complication in patients with end-stage renal disease on hemodialysis. The mainstay of phosphate management involves a low-phosphate diet and use of phosphate binders, yet these are often insufficient. This study was the first to use behavioral change techniques to encourage the use of phosphate binders and dietary modifications through a series of Phosphate Education and Planning (PEP) talks. DESIGN AND METHODS: A total of 46 hemodialysis patients with hyperphosphatemia were enrolled. All patients were eligible to receive a series of 4 talks, each with defined goals of the long-term management of serum phosphate levels. Qualitative data from the talks were gathered during each intervention, whereas serum phosphate was selected as an outcome measure. RESULTS: There was a modest improvement (-0.31 mg/dL) in the serum phosphate levels of the patients who received the entire PEP talk series. Furthermore, the most common self-identified barriers for patients were phosphate binder prescriptions not tailored to their eating routines and lack of resources for suitable dietary changes. CONCLUSIONS: The PEP talk series model is appropriate to manage persistent hyperphosphatemia despite usual management in outpatient dialysis unit by identifying patient-specific barriers and providing resources that can mitigate them. The strength of this model lies in using a multifaceted approach by applying both pharmacotherapy and dietary changes, along with behavioral change, to achieve lasting improvements in serum phosphate levels in hemodialysis patients with persistently elevated serum phosphate levels.

Kidney transplant recipients with polycystic kidney disease have a lower risk of post-transplant BK infection than those with end-stage renal disease due to other causes.

BACKGROUND: Polyomavirus-associated nephropathy is associated with high risk of kidney allograft loss. Whether the cause of native end-stage renal disease influences the risk of BK infection is unclear. METHODS: A retrospective, single-center study of 2741 adult kidney transplant recipients between 1994 and 2014 was performed. Recipients had end-stage renal disease due to polycystic kidney disease (PKD, n = 549), diabetes mellitus (DM, n = 947), hypertension (HTN, n = 442), or glomerulonephritis (GN, n = 803). RESULTS: A total of 327 recipients (12%) developed post-transplant BK viremia over a median follow-up time of 5 years. The incidence rate of BK viremia was lowest in patients with PKD (1.46 per 100 person-years) compared to other causes of ESRD (DM = 2.06, HTN = 2.65, and GN = 2.01 per 100 person-years). A diagnosis of PKD was associated with a lower risk of post-transplant BK viremia (adjusted HR (95% CI) = 0.67 (0.48-0.95), P = 0.02). BK nephropathy was significantly less common in patients with PKD (0.21 per 100 person-years) compared to those with HTN (0.80 per 100 person-years, P ≤ 0.001). Among patients with PKD, the risk of BK viremia was lower in patients with nephrectomy, compared to those without nephrectomy (adjusted HR (95% CI) = 0.42 (0.19-0.92), P < 0.05). CONCLUSION: ESRD due to PKD is associated with a lower risk of post-transplant BK infection. The renal tubular epithelial cells in PKD are unique; they are in a proliferative but non-differentiated state. Whether this characteristic of renal tubular epithelial cells alters the BK viral reservoir or replication in PKD patients warrants further study.

Silymarin inhibits melanoma cell growth both in vitro and in vivo by targeting cell cycle regulators, angiogenic biomarkers and induction of apoptosis.

Cutaneous malignant melanoma is the leading cause of death from skin diseases and is often associated with activating mutations of the proto-oncogene BRAF. To develop more effective strategies for the prevention or treatment of melanoma, we have examined the inhibitory effects of silymarin, a flavanoid from Silybum marianum, on melanoma cells. Using A375 (BRAF-mutated) and Hs294t (non BRAF-mutated but highly metastatic) human melanoma cell lines, we found that in vitro treatment with silymarin resulted in a dose-dependent: (i) reduction in cell viability; (ii) enhancement of either Go/G1 (A375) or G2-M (Hs294t) phase cell cycle arrest with corresponding alterations in cyclins and cyclin-dependent kinases; and (iii) induction of apoptosis. The silymarin-induced apoptosis of human melanoma cells was associated with a reduction in the levels of anti-apoptotic proteins (Bcl-2 and Bcl-xl), an increase in the levels of pro-apoptotic protein (Bax), and activation of caspases. Further, oral administration of silymarin (500 mg/kg body weight/2× a week) significantly inhibited (60%, P < 0.01) the growth of BRAF-mutated A375 melanoma tumor xenografts, and this was associated with: (i) inhibition of cell proliferation; (ii) induction of apoptosis of tumor cells; (iii) alterations in cell cycle regulatory proteins; and (iv) reduced expression of tumor angiogenic biomarkers in tumor xenograft tissues. These results indicate that silymarin may have a chemotherapeutic effect on human melanoma cell growth and warrant its further evaluation.

Intake of high-fat diet stimulates the risk of ultraviolet radiation-induced skin tumors and malignant progression of papillomas to carcinoma in SKH-1 hairless mice.

Previously, we showed that administration of a high-fat diet (HF-diet) to C57BL/6 mice exacerbates their response to short-term UVB radiation-induced inflammation in the skin. To explore the effects of an HF-diet on UVB-induced tumorigenesis, we have used the SKH-1 hairless mouse model in which the mice are exposed to UVB radiation (180mJ/cm(2)) three times a week for 24weeks. The development of UVB-induced skin tumors was rapid and the tumor multiplicity and tumor size were significantly higher (P<0.01-0.005) in the mice fed an HF-diet than the mice fed a control-diet (C-diet). Moreover, the malignant progression of UVB-induced papillomas to carcinomas was higher in HF-diet-fed mice. On analysis of tumors and tumor-uninvolved skin samples from the tumor-bearing mice, we found that administration of an HF-diet significantly enhanced the levels of UVB-induced expression of cyclooxygenase-2 (COX-2), prostaglandin E2 (P<0.01), and PGE2 receptors, and activation of NF-κB in the UVB-exposed skin as well as in tumors. In addition the HF-diet enhanced the expression of proinflammatory cytokines, including tumor necrosis factor-α (P<0.01), interleukin (IL)-1ß (P<0.01) and IL-6 (P<0.05) in the UVB-exposed skin as well as in tumors. Western blot analysis revealed that HF-diet enhanced the levels of epidermal cell proliferation, phosphatidylinositol 3-kinase and phosphorylation of Akt at Ser(473) in UVB-exposed skin and skin tumors. Collectively, these data demonstrate that the regular consumption of an HF-diet increases the risk of photocarcinogenesis in mice and that this is associated with enhanced expression of inflammatory mediators in the UVB-exposed skin and tumors.

Hemodialysis for the treatment of severe accidental hypothermia.

Severe hypothermia is defined as a core body temperature <28°C and is associated with in-hospital mortality rates of 50% or higher. Delays in rewarming and slower rates of rewarming are the most important prognostic factors associated with increased mortality. Arrhythmias are the most common cause of mortality in patients with severe accidental hypothermia. Electrolyte abnormalities such as hyperkalemia and hypocalcemia that may worsen when patients are rewarmed contribute to the risk of arrhythmias. Cardiopulmonary bypass (CBP) is considered the treatment of choice for active internal rewarming of patients with severe hypothermia, but it is not always available and is time consuming to initiate. We describe a case where hemodialysis (HD) was used to treat accidental hypothermia in a patient with an initial temperature of 23.5°C. Average rewarming rates of 1.5°C/hour were achieved. The advantages of HD when compared with CBP are that it is (1) more widely and readily available, (2) less invasive, (3) less expensive, and (4) can correct associated acidosis and electrolyte abnormalities commonly seen in patients with severe hypothermia.

Hypokalemia Due to Ectopic Adrenocorticotropic Hormone.

Hypokalemia is a common disorder in clinical practice. The underlying pathophysiology can be attributed to 3 main mechanisms: insufficient potassium intake, excessive urinary or gastrointestinal losses, and transcellular shift. Renal loss is the most common cause of hypokalemia. Renal loss of potassium can occur due to diuretics, mineralocorticoid excess or hypercortisolism (Cushing syndrome). Among patients with Cushing syndrome, ectopic adrenocorticotropic hormone (ACTH) is the most frequent cause. We present a case of hypokalemia and hypertension due to ectopic ACTH production leading to Cushing syndrome.

Lupus nephritis: management challenges during pregnancy.

Lupus nephritis (LN), a severe complication of systemic lupus erythematosus (SLE), leads to significant kidney inflammation and damage and drastically increases mortality risk. Predominantly impacting women in their reproductive years, LN poses specific risks during pregnancy, including pre-eclampsia, growth restrictions, stillbirth, and preterm delivery, exacerbated by lupus activity, specific antibodies, and pre-existing conditions like hypertension. Effective management of LN during pregnancy is crucial and involves carefully balancing disease control with the safety of the fetus. This includes pre-conception counseling and a multidisciplinary approach among specialists to navigate the complexities LN patients face during pregnancy, such as distinguishing LN flare-ups from pregnancy-induced conditions. This review focuses on exploring the complex dynamics between pregnancy and LN, emphasizing the management difficulties and the heightened risks pregnant women with LN encounter.

Association of Circulating 25-Hydroxyvitamin D and Recurrence of Glomerulonephritis in Kidney Transplant Recipients: The Wisconsin Allograft Recipient Database (WisARD).

Background: Recurrence of glomerulonephritis (GN) is a significant contributor to long-term allograft failure among kidney transplant recipients (KTRs) with kidney failure because of GN. Accumulating evidence has revealed the role of vitamin D in both innate and adaptive immunity. Although vitamin D deficiency is common among KTRs, the association between 25-hydroxyvitamin D (25[OH]D) and GN recurrence in KTRs remains unclear. Methods: We analyzed data from KTRs with kidney failure caused by GN who received a transplant at our center from 2000 to 2019 and had at least 1 valid posttransplant serum 25(OH)D measurement. Survival analyses were performed using a competing risk regression model considering other causes of allograft failure, including death, as competing risk events. Results: A total of 67 cases of GN recurrence were identified in 947 recipients with GN followed for a median of 7.0 y after transplant. Each 1 ng/mL lower serum 25(OH)D was associated with a 4% higher hazard of recurrence (subdistribution hazard ratio [HR]: 1.04; 95% confidence interval [CI], 1.01-1.06). Vitamin D deficiency (≤20 ng/mL) was associated with a 2.99-fold (subdistribution HR: 2.99; 95% CI, 1.56-5.73) higher hazard of recurrence compared with vitamin D sufficiency (≥30 ng/mL). Results were similar after further adjusting for concurrent urine protein-creatinine ratio, serum albumin, and estimated glomerular filtration rate (eGFR). Conclusions: Posttransplant vitamin D deficiency is associated with a higher hazard of GN recurrence in KTRs. Further prospective observational studies and clinical trials are needed to determine any causal role of vitamin D in the recurrence of GN after kidney transplantation. More in vitro and in vivo experiments would be helpful to understand its effects on autoimmune and inflammation processes.