Consequences of kidney donation by age in Japanese living kidney donors: a single-center study.

BACKGROUND: Elderly living kidney donors (LKDs) are becoming increasingly important in countries with a high prevalence of living-donor kidney transplants and an aging society. This study explored the features of elderly LKDs, focusing on their subsequent outcomes. METHODS: This single-center, retrospective, observational study included eligible LKDs who donated their kidneys between April 2008 and July 2022. LKDs were categorized into an elderly (≥70 years at donation) or a non-elderly group (<70 years). We examined pre-operative characteristics and post-operative outcomes, such as kidney function, complications, development of end-stage kidney disease (ESKD), and mortality. RESULTS: Of the 188 LKDs observed for a median of 5.7 years, 31 were in the elderly group (16.5%) and 157 (83.5%) were in the non-elderly group (mean age 72.5 ± 2.7 and 58.2 ± 7.3 years, respectively). No significant differences were observed in hospital stay length or peri-operative complications between groups. Both groups experienced a similar decline in post-donation estimated glomerular filtration rate (eGFR)-approximately 37%. In the elderly group, four LKDs died, and one progressed to ESKD. In the non-elderly group, two LKDs died, and none progressed to ESKD. The cause of death was not strongly suspected to be associated with the donation. CONCLUSIONS: eGFR was maintained even in elderly LKDs post-donation. Prioritizing LKDs' safety is paramount; however, donations from elderly people would be acceptable, considering their life expectancy. This can expand the pool of living kidney donors and address the growing demand for kidney transplants.

Twenty-four-hour Urinary Salt Excretion on Admission Predicts Significant Weight Loss with Seven-day Dietary Salt Restriction in Hospitalized Patients with Chronic Kidney Disease: A Single-center Study.

In patients with chronic kidney disease (CKD), restricting dietary salt is recommended to prevent fluid retention. Rapid weight loss is often observed when CKD patients with a high salt intake are hospitalized and started on a low-salt diet. We investigated the effects of 7-day dietary salt restriction on weight loss in hospitalized patients with CKD. During the 7-day hospitalization, a low-salt (6 g/day) and low-protein (0.6-0.8 g/kg/day ideal body weight) diet was served to all patients. Urine samples were collected for the first 24 h after admission, and patients were divided into quartiles (Q1-Q4) by urinary salt excretion. Body weight was measured on days 1 and 7. Weight loss after admission was compared among the groups. Factors associated with weight loss were evaluated by multivariate logistic regression. The mean age of the patients was 70.3 ± 11.7 years, and 73% were male. Mean weight loss was 1.6 ± 1.7 kg on day 7. Weight loss was significantly greater in Q3 and Q4 than in Q1 (P = 0.009 and P <0.001, respectively). In the univariate analysis, weight loss correlated positively with 24-h urinary salt excretion on admission (γ2 = 0.146) and body mass index (γ2 = 0.223). The 24-h urinary salt excretion on admission and BMI were independently associated with weight loss of >2 kg. The adjusted odds ratios (95% confidence interval) were 1.24 (1.13-1.36) and 1.15 (1.07-1.22), respectively. Twenty-four-hour urinary salt excretion on admission is useful for predicting significant weight loss with short-term dietary salt restriction.

Association between inpatient education program for patients with pre-dialysis chronic kidney disease and new-onset cardiovascular disease after initiating dialysis.

BACKGROUND: The association between inpatient education programs (IEPs) for patients with pre-dialysis chronic kidney disease (CKD) and new-onset cardiovascular disease (CVD) after initiating dialysis is unclear. METHODS: We conducted a retrospective cohort study between January 1, 2011 and December 31, 2018, evaluating CKD patients who were divided into two groups based on whether or not they participated in IEPs. The primary outcome was a new-onset CVD event after initiating dialysis. Cumulative incidence function was used to describe new-onset CVD considering the competing outcome of death. Additionally, Cox proportional hazards models were used to estimate the hazard ratio of new-onset CVD between IEP and non-IEP groups. RESULTS: Of the 493 patients, 131 (26.6%) patients had participated in IEPs. The IEP group had a significantly longer duration of CKD management by nephrologists (median 142 vs. 115 days, P = 0.007), lower rate of emergency hospital admissions (9.9% vs. 27.1%, P < 0.001), better ability to perform activities of daily living (Grade J; 81.6% vs. 69.1%, P = 0.046), higher rate of pre-placement of permanent vascular access or peritoneal dialysis catheters (82.4% vs. 59.4%, P < 0.001), and a higher serum albumin level at the beginning of dialysis (3.5 ± 0.5 vs. 3.3 ± 0.6 g/dL, P < 0.001). The cumulative incidence of new-onset CVD at three years after initiating dialysis in the IEP and non-IEP groups was 16.9% and 22.5%, respectively. The hazard ratio for new-onset CVD after initiating dialysis in the IEP group was 0.63 (95% CI: 0.41-0.97, P = 0.036). CONCLUSION: IEPs were associated with a lower rate of new-onset CVD after initiating dialysis.

Acute tubulointerstitial nephritis possibly caused by vedolizumab for ulcerative colitis in a kidney transplant recipient: A case report.

Vedolizumab, which is used to effectively treat ulcerative colitis (UC), is a humanized monoclonal antibody that specifically inhibits α4ß7 integrin on lymphocytes and prevents lymphocyte migration into the intestinal tissues. Herein, we report a case of acute tubulointerstitial nephritis (ATIN) probably caused by vedolizumab in a kidney transplant recipient (KR) with UC. Approximately 4 years after kidney transplantation, the patient developed UC and was treated initially with mesalazine. Treatment continued with the addition of infliximab later; however, he was hospitalized because of poor symptom control and treated with vedolizumab. His graft function declined rapidly after vedolizumab was administered. Allograft biopsy revealed ATIN. Since no evidence of graft rejection was found, vedolizumab-associated ATIN was diagnosed. The patient was treated with steroids, and his graft function improved. Unfortunately, he finally underwent total colectomy considering that UC was refractory to medical treatment. Previously, cases of vedolizumab-induced acute interstitial nephritis have been reported; however, none were associated with KRs. This is the first report of ATIN in KR which was possibly induced by vedolizumab.

Renal hypouricemia in a recipient of living-donor kidney transplantation: a case report and literature review.

Hypouricemia in kidney transplant (KT) recipients is rare since they usually have subnormal kidney function which raises serum uric acid level. Recently, interests in pathogenesis of hypouricemia have been increasing due to the understanding of the role of uric acid transporter in renal hypouricemia (RHUC). We herein report the case of RHUC consequently developed in a KT recipient from a living donor with RHUC diagnosed by the detailed urinary and genetic test. A 73-year-old Japanese man underwent KT, and the donor was his wife who had hypouricemia [serum uric acid (S-UA) 0.6 mg/dL]. Nine months after KT, the recipient's S-UA was low (1.5 mg/dL) with serum creatinine (S-Cr) of 1.56 mg/dL, and fractional excretion of UA (FEUA) was high (59.7%; normal < 10%), indicating RHUC. Regarding the donor's information, S-Cr, S-UA, and FEUA were 0.95 mg/dL, 1.0 mg/dL, and 54.5%, respectively. To investigate further on the pathogenesis of RHUC in both the recipient and the donor, we performed genetic tests. The donor had a homozygous mutation of W258X in the SLC22A12 gene and the recipient had a wild type of W258X. Finally, we reviewed the previous literature on RHUC among KT recipients and discussed the strategy of follow-up for these patients.

Effects of age and sex on the relationship between body fat area and kidney events in patients with chronic kidney disease.

We examined the effects of age and sex on the relationship between body fat area and kidney events. We included 367 chronic kidney disease patients between 2011 and 2017. Patients' median age was 73.0 years; 262 (71.4%) patients were male. The median estimated glomerular filtration rate was 20.2 mL/min/1.73 m2 . During the observation period, 187 patients developed kidney events. In males aged <75 years, high subcutaneous fat area was a risk factor for kidney events (hazard ratio: 1.06, 95% CI: 1.02-1.11). In females aged <75 years, high visceral fat area reduced kidney events (hazard ratio: 0.83, 95% CI: 0.71-0.97). In males and females ≥75 years, visceral fat area and subcutaneous fat area were not associated with kidney events. Body fat area was not a risk factor for chronic kidney disease progression in elderly patients. Opposite effects, in sex-related body fat and kidney events, were shown in young patients.

Inpatient educational program delays the need for dialysis in patients with chronic kidney disease stage G5.

BACKGROUND: Inpatient educational programs (IEPs) for patients with chronic kidney disease (CKD) decrease CKD progression. However, patients with end-stage kidney disease who started dialysis during the observation period were excluded from previous studies. METHODS: After adjusting for age, sex, baseline estimated glomerular filtration rate, hemoglobin level, and the presence of diabetes mellitus using 1:1 propensity score matching (caliper width of 0.008) in the groups that did and did not receive an IEP, we compared the time period from the beginning of CKD stage G5 to the start of dialysis and patient characteristics at the start of dialysis. RESULTS: Prior to matching, 41 patients received an IEP and 260 did not. After propensity score matching, the 41 patients who received an IEP had a longer period from the beginning of stage G5 to the start of dialysis (344 vs. 257 days, P = 0.011), shorter hospitalization period upon the start of dialysis (14 vs. 18 days, P = 0.015) compared with the 41 patients who did not receive an IEP. In addition, the proportion of patients with a planned start of dialysis tended to be higher in the IEP group (95.1 vs. 83.0%, P = 0.077). CONCLUSION: An IEP may delay the start of dialysis in patients with end-stage kidney disease, contribute to better preparation of vascular access placement and the smoother start of dialysis.

Arteriovenous fistulas after ultrasound-guided needle biopsy of kidney allografts and treatment outcomes after transcatheter embolization: A single-center experience in Japan.

BACKGROUND: Arteriovenous fistula (AVF) is one of the vascular complications after allograft biopsy, and their reported incidence rates range widely. Transcatheter embolization (TE) is a common AVF treatment in kidney allografts. However, information on AVF incidence and features and TE outcomes in Japanese kidney transplant (KT) recipients is lacking. METHODS: This study investigated 270 protocol or clinically indicated kidney allograft biopsies in 129 KT recipients during 2010-2016 at a single-center using standardized methods (16-gauge needle and ultrasound guidance). We recorded the incidence and clinical features of AVF using currently recommended standardized methods of allograft biopsy and TE outcomes regarding allograft function up to 12 months after the procedure in Japanese KT recipients. RESULTS: AVF incidence was 2.6% (seven cases). The time from biopsy to AVF diagnosis was 7 (median, interquartile range: 5-117, range: 1-318) days. The time from biopsy to AVF diagnosis was significantly shorter in symptomatic cases (gross hematuria) than in asymptomatic cases (median 6 vs. 117 days, p = 0.034). Symptomatic patients underwent TE within a shorter time (0-6 days) than asymptomatic patients (25-104 days). There were no complications, and allograft function was stable up to 12 months after TE despite using contrast media and partial renal infarction. CONCLUSIONS: AVF does occur in certain probabilities. AVF formation can occur without apparent bleeding and exist for a long time after allograft biopsy. TE is a safe and immediate treatment for AVF in kidney allograft.

Effect of Long-term Peritoneal Dialysis on Change in Visceral Fat Area: A Single-Center Experience.

INTRODUCTION: Visceral fat area (VFA) is known to increase after initiation of peritoneal dialysis (PD). However, the factors contributing to the increase in VFA in long-term PD patients have not been sufficiently elucidated. The present study investigated factors that affect VFA in patients who continue PD for ≥3 years. METHODS: Twenty patients (63.1 ± 10.3 years, 9 men, 11 diabetic patients) between January 2008 and January 2015 were included. VFA, subcutaneous fat area (SFA) and waist circumference at initiation and follow-up were measured at the level of the umbilicus by computed tomography using an image analysis system. Change in VFA was defined as the value obtained by dividing VFA at the final follow-up by that at the initiation. The correlations between clinical parameters at initiation and changes in VFA were analyzed. RESULTS: There was no significant change in body weight (57.6 ± 10.4 vs 58.3 ± 7.8 kg, P = 0.296) during the mean final follow-up period of 55 ± 13 months, although VFA increased significantly (103.6 ± 39.2 vs 122.6 ± 38.3 cm2, P = 0.030). Although subcutaneous fat area (SFA) did not change (124.7 ± 52.3 vs 124.5 ± 49.2 cm2, P = 0.989), waist circumference increased significantly (79.4 ± 8.4 vs 83.7 ± 6.9 cm, P = 0.010). SFA (r = -0.735, P < 0.001), waist circumference (r = - 0.644, P = 0.002), high-density lipoprotein cholesterol (HDL-C) (r = 0.487, P = 0.029), and age (r = 0.507, P = 0.023) correlated significantly with changes in VFA. CONCLUSIONS: VFA might increase with long-term PD in patients with end-stage kidney disease who have high HDL-C, small SFA, and small waist circumference at initiation.

Seasonal prevalence of hyponatremia in the emergency department: impact of age.

BACKGROUND: Hyponatremia is one of the most commonly encountered electrolyte disorders in emergency department (ED). Seasonal fluctuations of the prevalence of hyponatremia has been reported. We investigated the impact of age on the seasonal prevalence of hyponatremia in the emergency department in Japan. METHODS: Total of 8377 patients presented to the ED between January 2015 and December 2016 were reviewed. The adult group aged between 18 and 64 years old consisted of 3656 patients and the elderly group aged over 65 years consisted of 4721 patients. Information collected included age, sex, serum sodium, and serum creatinine. Hyponatremia was defined as a serum sodium leve1 < 135 mEq/L and severe hyponatremia was defined as a serum sodium level < 125 mEq/L. RESULTS: Prevalence of hyponatremia was significantly higher in the elderly group than in the adult group (17.0% vs. 5.7%, p < 0.001). Similarly, the prevalence of severe hyponatremia was significantly higher in the elderly group than in the adult group (1.9% vs. 0.3%, p < 0.001). Prevalence of hyponatremia and severe hyponatremia was significantly higher in the elderly group than in the adult group in all seasons. In the elderly group, there was a significant correlation between weather high temperature during summer and prevalence of hyponatremia (r = 0.510, p = 0.011). CONCLUSION: There was a major impact of age on the seasonal prevalence of hyponatremia and severe hyponatremia. Strategies to prevent hyponatremia and severe hyponatremia should be taken especially in the elderly patients during summer.

Early Postoperative Complications of Peritoneal Dialysis Catheter Surgery Conducted by Nephrologists: A Single-Center Experience Over an Eight-Year Period.

The results of several recent studies indicate that the practice of peritoneal dialysis catheter (PDC) insertion by nephrologists is safe. However, few studies have addressed the important issue of safety in surgeries related to PD, including PDC removal and other types of surgery. In the present study, we aimed to verify whether the incidence of early postoperative complications for surgical procedures related to PD and performed by nephrologists meets the audit standards of clinical practice guidelines for peritoneal access.Between April 2008 and July 2016 at our hospital, 282 patients underwent various types of PD-related surgery conducted by 17 nephrologists. The surgery types were the Moncrief-Popovich technique (n = 74), PDC exteriorization (n = 62), conventional laparotomy insertion (n = 29), PDC removal (n = 70), partial replacement (n = 32), unroofing or cuff shaving (n = 7), and others (n = 8).Bowel perforation and significant hemorrhage did not occur at the time of PDC insertion and removal. Although peritonitis was not evident, exit-site and tunnel infection within 2 weeks of PDC insertion by conventional laparotomy or exteriorization after the Moncrief-Popovich technique occurred in 3 of 91 patients (3.3%). The PDC malfunctioned in 2 of 103 patients (1.9%) after the Moncrief-Popovich technique because of PDC occlusion with a fibrin plug. Dialysate leaks occurred in 2 of 103 patients (1.9%). Partial replacement and unroofing or cuff shaving for refractory PDC infection and other type of surgeries were not associated with serious complications.The incidence of complications after surgery related to PD was low at our institution. The incidences of complications met the audit standards in the guidelines, indicating that surgery by nephrologists is safe and effective.