De novo Inflammatory Bowel Disease in Kidney Transplant Recipients: A Single-Center Case Series Study.

Introduction: Gastrointestinal complications are common after solid organ transplantation. New-onset inflammatory bowel disease (IBD) after transplantation (de novo) is a major differential diagnosis of diarrhea after liver transplantation (LT) because of its high incidence in the field. However, the incidence of IBD after kidney transplantation (KT) remains unknown. Methods: This case series comprised six de novo IBD patients who had undergone KT at our hospital from April 1998 to December 2020. In this period, 232 KT recipients were identified. Participants were analyzed based on their colonoscopy diagnoses. Detailed clinical information regarding both KT- and IBD-related symptoms or outcomes was obtained, and we calculated the incidence of de novo IBD from the date of KT. Results: Of the 232 recipients in the median observation period of 6.1 (interquartile range: 2.6, 10.8) years, six recipients (one with Crohn's disease and five with ulcerative colitis) were diagnosed with de novo IBD. The incidence of de novo IBD after KT was 355.8/100,000 person-years (95% confidence interval, 159.8-791.9 per 100,000 person-years). Bloody stools and diarrhea did not always occur, with bloody stools occurring in three and diarrhea in 2 patients at the time of diagnosis. No recipient developed graft failure or extraintestinal complications (e.g., IBD-related nephritis or arthritis). Conclusion: Despite a small sample size, this study's results indicate that the incidence of de novo IBD after KT may be similar to that after LT and higher than that in the general population. Larger studies are required to validate these preliminary findings.

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.

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.

Romosozumab improves low bone mineral density in a postmenopausal woman undergoing chronic hemodialysis and treated with a calcium-sensing receptor agonist.

Preventing osteoporotic fractures is an issue requiring urgent attention to reduce mortality. However, unlike chronic kidney disease-mineral and bone disorder (CKD-MBD), osteoporosis is inadequately addressed in patients undergoing chronic dialysis. In fact, little is known about the proper use of anti-osteoporotic drugs for patients with CKD-MBD. A recent study showed that romosozumab, an anti-osteoporotic drug, increased bone mineral density in osteoporotic patients on hemodialysis without clinically significant adverse events. However, the efficacy and safety of coadministering romosozumab with a calcium-sensing receptor (CaSR) agonist, a pivotal drug used in the management of CKD-MBD, remain unclear. Here, we report the case of a postmenopausal woman undergoing chronic hemodialysis and treated with add-on romosozumab for osteoporosis to CaSR agonist for secondary hyperparathyroidism. After 1 year of treatment, her bone mineral density increased; however, hypocalcemia occurred during the treatment. These results suggest that the concomitant use of romosozumab with CaSR agonist may be a possible treatment option for severe osteoporosis in postmenopausal women receiving chronic hemodialysis with a high fracture risk, but serum calcium levels should be monitored closely and those at risk of ectopic calcification might not be ideal candidates for such treatment.

Tonicity Matters, Especially in Complex Hyponatremia Resulting from Pseudo-, Trans-locational, and True Hypotonic Hyponatremia: An Educational Case Report.

Serum tonicity is defined by the serum concentrations of sodium (sNa) and glucose, which can promote free water movement across intra/extracellular compartments. Rapid changes in serum tonicity can cause brain damage. We herein report an educational case of a patient with hyponatremia (sNa: 112 mEq/L) concomitant with acute alcoholic pancreatitis. The cause of hyponatremia was considered complex. Pseudo- and trans-locational natremia was secondary to hyperglycemia (721 mg/dL) and hypertriglyceridemia (1,768 mg/dL), respectively, and true hypotonic hyponatremia. Regarding sNa correction, rapid correction was suspected. However, this was safely managed by monitoring tonicity (not sNa or osmolarity), thereby avoiding brain damage.

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.

Optimizing Intraoperative Blood Pressure to Improve Outcomes in Living Donor Renal Transplantation.

BACKGROUND: Adequate renal perfusion at the time of unclamping is important because it has been known to affect outcomes in renal transplantation. Nevertheless, the ideal intraoperative systolic arterial pressure (SAP) has not been well defined. METHODS: We performed a retrospective analysis of 106 living donor renal transplants performed at our center from June 2010 to May 2019. We divided the cohort into 2 groups according to our center's goal SAP of ≥150 mm Hg: 57 patients had SAP ≥150 mm Hg and 49 patients had SAP <150 mm Hg. We analyzed pretransplant characteristics, intraoperative measurements, and postoperative laboratory values to validate our center's target SAP at the time of reperfusion. This study strictly complied with the Helsinki Congress and the Istanbul Declaration regarding donor sources. RESULTS: Patients with SAP ≥150 mm Hg had been on dialysis for a significantly shorter duration before transplant compared with those who had SAP <150 mm Hg. In the SAP ≥150 mm Hg group, urinary sodium excretion normalized earlier, and they had a significantly smaller stroke volume variation, higher cardiac output and cardiac index, earlier initial urination, and higher intraoperative urine output. There were no differences in intraoperative volume repletion, central venous pressure, or postoperative estimated glomerular filtration rate. CONCLUSION: Achieving SAP ≥150 mm Hg at the time of reperfusion may be associated with early stabilization of graft function. Nevertheless, our data suggested that recipients with a prolonged dialysis history are less likely to achieve SAP ≥150 mm Hg at the time of unclamping in living donor renal transplantation.

Is the Living Donor Kidney Profile Index Valuable in Japanese Patients?

INTRODUCTION: The Living Kidney Donor Profile Index (LKDPI) was recently proposed in the United States to evaluate living donor quality. Japan has a largely different renal transplant circumstance, such as a high ABO incompatibility rate. The aim of this study was to validate the LKDPI among the Japanese population and adjust the score. METHODS: We performed a retrospective analysis of 133 living donors in renal transplant in our institution. We analyzed the clinical characteristics and outcomes, and created a modified LKDPI score considering the favorable ABO incompatible kidney transplant outcomes in Japan. RESULTS: Median (interquartile range [IQR]) donor age was 59 (51 to 65) and median (IQR) body mass index was 22.9 kg/m2 (20.9 to 25.2). ABO incompatibility rate was 28.5%. Median (IQR) donor estimated glomerular filtration rate (eGFR) (Chronic Kidney Disease Epidemiology Collaboration equation) was 108.7 mL/min/1.73 m2 (99.9 to 115.5). The 1-year graft survival rate was 98.5%, and the 3-year graft survival rate was 97%. The incidence of antibody mediated rejection was 5.2%. The median (IQR) LKDPI score was 30.2 (11.8 to 46.8). This was significantly higher than the previously reported score in the United States, which was 12.8 (-0.8 to 27.2). The modified LKDPI (mLKDPI) score was 23.2 (4.1 to 35.1). LKDPI and mLKDPI did not show a diagnostic value in graft survival; however, LKDPI and mLKDPI showed significant diagnostic value in eGFR at 1 year (area under the curve [AUC]=0.627, P = .017; and AUC=0.673, P = .01). CONCLUSION: Our outcomes had better survival even though with higher ABO incompatibility rate. According to original LKDPI, our donor pool is higher than the general US population. In this study, lower LKDPI tended to be associated with good allograft function, and mLKDPI has better diagnostic value than LKDPI. To compare internationally, an adjusted model for Japan might be necessary based on the outcomes of a large population.

Impact of Very Low-Dose Trimethoprim-Sulfamethoxazole on Serum Creatinine after Renal Transplantation: A Retrospective Study.

BACKGROUND: It is well known that high-dose trimethoprim, through its effect of inhibiting creatinine secretion, increases serum creatinine levels without changes in real glomerular filtration rate. However, there has been no report regarding the effect of very low-dose trimethoprim on serum creatinine levels after renal transplantation. METHODS: We retrospectively investigated 76 renal transplantation recipient outpatients who completed their course of initial prophylaxis at our institution. Twelve patients who experienced events that might affect their serum creatinine levels were excluded. Fifty-one patients who required readministration of trimethoprim-sulfamethoxazole to prevent a possible outbreak of pneumocystis jirovecii pneumonia and 13 patients who did not receive readministration (control) were analyzed. Dosage was 80 mg/400 mg (per tablet), administered as 3 tablets per week for 30.6 ± 13.5 days. This study strictly complied with the Helsinki Congress and the Istanbul. Declaration regarding donor source. RESULTS: All patients completed readministration without adverse events. Serum creatinine increased significantly in the readministration group (1.40 ± 0.64 mg/dL to 1.48 ± 0.70 mg/dL, P < .01) while not in the control group. The higher the initial serum creatinine level, the greater the increase of Δ serum creatinine (R = 0.59, P < .001). Sex, baseline urine protein level, angiotensin-converting enzyme inhibitor/angiotensin receptor blocker use, donor type, and time after renal transplantation did not affect Δ serum creatinine. Serum creatinine returned to baseline levels after cessation. CONCLUSIONS: Very low-dose trimethoprim-sulfamethoxazole prophylaxis significantly raised serum creatinine reversibly by 6% after renal transplantation.

Prediction model of compensation for contralateral kidney after living-donor donation.

BACKGROUND: Compensation of contralateral kidney function after living-donor kidney donation is well known, and many predictive factors have been proposed. However, no prediction model has been proposed. This study was performed to establish a tool with which to estimate the degree of compensation of the contralateral kidney after living-donor kidney donation. METHODS: We retrospectively analyzed 133 living donors for renal transplantation in our institution. We defined a favorable compensation as a post-donation estimated glomerular filtration rate (eGFR) at 1 year (calculated by the Chronic Kidney Disease Epidemiology Collaboration equation) of > 60% of the pre-donation eGFR. We analyzed the living donors' clinical characteristics and outcomes. RESULTS: The median (range) donor age was 59 (24-79) years, median (range) body mass index was 22.9 (16.8-32.7) kg/m2, and median (range) body surface area was 1.6 (1.3-2.0) m2. All donors were Japanese, and 73% of the donors were biologically related. The median (range) donor pre-donation eGFR was 108.7 (82-144) ml/min/1.73 m2, and the median (range) post-donation eGFR at 1 year was 86.9 (43-143) ml/min/1.73 m2. Eighty-six percent of donors had compensatory hypertrophy. In the univariate analysis, age, female sex, history of hypertension, body surface area, and pre-donation eGFR were significantly associated with hypertrophy (p < 0.05). In the multivariate analysis, age, female sex, history of hypertension, and ratio of the remnant kidney volume to body weight were significantly associated with hypertrophy (p < 0.05). Based on these results, we created a compensation prediction score (CPS). The median (range) CPS was 8.7 (1.1-17.4). Receiver operating characteristic analysis showed strong diagnostic accuracy for predicting favorable compensation (area under the curve, 0.958; 95% confidence interval, 0.925-0.991, p < 0.001). The optimal cut-off value of the CPS was 5.0 (sensitivity, 92.0%; specificity, 89.5%). The CPS had a strong positive correlation with the post-donation eGFR (R = 0.797, p < 0.001). CONCLUSION: The CPS might be useful tool with which to predict a favorable compensation of the contralateral kidney and remnant kidney function. If the CPS is low, careful management and follow-up might be necessary. Further investigations are needed to validate these findings in larger populations.