Yasuhiko Ito

Regional variation in the treatment and prevention of peritoneal dialysis-related infections in the Peritoneal Dialysis Outcomes and Practice Patterns Study

BackgroundnPeritoneal dialysis (PD)-related infections lead to significant morbidity. The International Society for Peritoneal Dialysis (ISPD) guidelines for the prevention and treatment of PD-related infections are based on variable evidence. We describe practice patterns across facilities participating in the Peritoneal Dialysis Outcomes and Practice Patterns Study (PDOPPS).nnnMethodsnPDOPPS, a prospective cohort study, enrolled nationally representative samples of PD patients in Australia/New Zealand (ANZ), Canada, Thailand, Japan, the UK and the USA. Data on PD-related infection prevention and treatment practices across facilities were obtained from a survey of medical directors.nnnResultsnA total of 170 centers, caring for >11u2009000 patients, were included. The proportion of facilities reporting antibiotic administration at the time of PD catheter insertion was lowest in the USA (63%) and highest in Canada and the UK (100%). Exit-site antimicrobial prophylaxis was variably used across countries, with Japan (4%) and Thailand (28%) having the lowest proportions. Exit-site mupirocin was the predominant exit-site prophylactic strategy in ANZ (56%), Canada (50%) and the UK (47%), while exit-site aminoglycosides were more common in the USA (72%). Empiric Gram-positive peritonitis treatment with vancomycin was most common in the UK (88%) and USA (83%) compared with 10-45% elsewhere. Empiric Gram-negative peritonitis treatment with aminoglycoside therapy was highest in ANZ (72%) and the UK (77%) compared with 10-45% elsewhere.nnnConclusionsnVariation in PD-related infection prevention and treatment strategies exist across countries with limited uptake of ISPD guideline recommendations. Further work will aim to understand the impact these differences have on the wide variation in infection risk between facilities and other clinically relevant PD outcomes.

A patient with arteriovenous fistula of simultaneously performed anastoplasty for excessive blood flow and graft bypass to secure an outflow tract

Introduction: We report a case in which we performed an anastomotic part septal formation surgery (anastoplasty) and artificial blood vessel replacement surgery. Case Description: When forearm arteriovenous fistula occlusion of a dialysis patient was observed, there was a thrombus in the vein of the whole forearm from the anastomotic part. We performed a septum formation surgery to suppress the blood flow in the vein near the anastomotic site, and artificial blood vessel replacement was performed on the high stenosis of the cephalic vein of the elbow. Postoperative blood flow was stable and hemodialysis was possible. Although there are various blood flow suppression methods for suppressing excessive blood flow, we report a case in which an anastomotic part septal formation surgery and artificial blood vessel replacement to secure an outflow passage were performed at the same time. Conclusion: Anastoplasty for excessive blood flow is considered to be an effective means in this case.

Differences in peritoneal solute transport rates in peritoneal dialysis

BackgroundUltrafiltration failure associated with peritoneal membrane dysfunction is one of the main complications for patients on long-term peritoneal dialysis (PD). The dialysate-to-plasma concentration ratio (D/P) of creatinine is widely used to assess peritoneal membrane function. However, other small-sized solutes have not been studied in detail as potential indicators of peritoneal permeability.MethodsWe studied the D/Ps of small, middle-sized and large molecules in peritoneal equilibration tests in 50 PD patients. We applied metabolomic analysis of comprehensive small molecular metabolites using capillary electrophoresis time-of-flight mass spectrometry.ResultsD/Ps of middle-sized and large molecules correlated positively with D/P creatinine. Most D/Ps of small molecules correlated positively with D/P creatinine. Among 38 small molecules contained in the dialysate, urea, citrulline and choline showed significantly lower ability to permeate than creatinine. In the relationship between D/Ps of creatinine and small molecules, regression coefficients of three molecules were less than 0.3, representing no correlation to D/P creatinine. Five molecules showed negative regression coefficients. Among these molecules, hippurate and 3-indoxyl sulfate showed relatively high teinpro binding rates, which may affect permeability. Serum concentrations of two molecules were higher in the Low Kt/V group, mainly due to high protein binding rates.ConclusionsD/Ps of some molecules did not correlate with D/P creatinine. Factors other than molecular weight, such as charge and protein binding rate, are involved in peritoneal transport rates. Metabolomic analysis appears useful to analyze small molecular uremic toxins, which could accumulate in PD patients, and the status of peritoneal membrane transport for each molecule.

Therapeutic efficacy of rituximab for the management of adult-onset steroid-dependent nephrotic syndrome: a retrospective study

BackgroundRecent reports have described the efficacy of rituximab in treating steroid-dependent nephrotic syndrome (SDNS) in pediatric patients. However, few reports describe data regarding adult-onset SDNS. We investigated the efficacy of rituximab for the management of adult-onset SDNS.MethodsWe performed a retrospective cohort study investigating eight patients with adult-onset SDNS who were treated with rituximab. Clinical data were obtained at the initiation of rituximab therapy. The primary outcomes evaluated were successful suppression of relapses and CD19+ cells after rituximab treatment. The corticosteroid- and immunosuppressant-sparing effect and adverse events were additionally evaluated.ResultsAll eight patients were diagnosed with minimal change nephrotic syndrome and received immunosuppressants in addition to corticosteroid. Total number of relapses was 10.5 times as a median value. Rituximab administration was repeated in two patients, whereas six received single-dose rituximab. Three of eight (37.5%) patients showed relapse after rituximab therapy. A rituximab-induced depletion in CD19+ cells noted initially was followed by their reappearance in all patients. There were cases with no relapse after the reappearance of CD19+ cells. The median relapse time pre- and post-rituximab therapy showed a decrease from 1xa0time/year (interquartile range [IQR] 1–3xa0times/year) to 0xa0time/year (IQR 0–1xa0time/year). Rituximab treatment induced a significant reduction in the required doses of corticosteroid and cyclosporine (Pu2009<u20090.01). No serious adverse events were observed.ConclusionRituximab treatment was effective not only in childhood-onset but also in adult-onset SDNS. Further studies are needed to establish optimal treatment regimens.

Investigation on the benefits of mycophenolate mofetil and therapeutic drug monitoring in the treatment of Japanese patients with lupus nephritis

BackgroundMycophenolate mofetil (MMF) is recommended as a first-line immunosuppressant to treat lupus nephritis (LN). Prognosis and therapeutic response in LN are known to vary depending on race. We investigated the benefits of MMF and therapeutic drug monitoring (TDM) in the treatment of Japanese LN patients.MethodsIn this retrospective cohort study, a total of 20 patients with LN who started MMF treatment were included. Clinical data were collected regularly after MMF administration. We evaluated complete remission (CR) rate as the primary outcome. Predictors of CR were identified using univariate and multivariate analyses. In the research of TDM, the correlation with the area under the curve (AUC) was analyzed at MMF dose, single-point value, treatment response, and adverse events.ResultsOverall, 70% of cases showed CR; both flare-ups and refractory cases had favorable results. Cases of LN with nephrotic syndrome (NS) or class III/IVu2009+u2009V showed a significantly lower CR rate (pu2009<u20090.005). The ratio of maintaining CR after MMF therapy was as high as 85.7%. In multivariate analysis, NS was an independent negative predictor of CR (HR 0.09, 95% confidence interval 0.01–0.81; pu2009=u20090.03). The relationship between AUC and MMF dose was low, and AUC correlated with trough level (ru2009=u20090.73). AUC tended to be high in the treatment responder (pu2009=u20090.09), but did not correlate with adverse events of infection (pu2009=u20090.92).ConclusionMMF is a beneficial treatment option for Japanese LN patients, and further investigation on TDM-based therapy is needed.

Successful renal transplantation to a recipient with type II cryoglobulinemia: a case report

BackgroundRecurrence of glomerulonephritis is an important risk factor for renal graft dysfunction. Cryoglobulinemia is known as a relatively rare cause of renal failure, and doctors are usually hesitant to perform transplantation on a recipient with cryoglobulinemia because of the risk for graft loss. We present a case of renal transplantation on a patient with organ manifestations of type II cryoglobulinemia.Case presentationAt the age of 44xa0years, the patient developed acute kidney injury and purpura on the lower extremities with type II cryoglobulinemia after interferon therapy for hepatitis C virus. Cryoglobulinemic glomerulonephritis was suspected; however, despite immunosuppressive therapy combined with plasmapheresis, she eventually needed hemodialysis treatment. She was referred to us at the age of 49xa0years for renal transplantation. Cryocrit was 14% and the organ manifestations persisted, including the lower extremity purpura and neurologic symptoms. After monitoring and confirming sufficient suppression of cryoglobulin concentration by immunosuppressive treatment with prednisolone, cyclophosphamide, and rituximab combined with plasmapheresis, the operation was performed. After transplantation, the cryoglobulin concentration was continuously monitored, and plasmapheresis and rituximab infusion were performed as appropriate. Her graft function has remained stable for 2xa0years and 6xa0months.ConclusionOur case suggested that a patient with cryoglobulinemia and persistent organ manifestations can receive a renal graft if the cryoglobulin concentration is sufficiently controlled by pretransplant treatment.

Clinical features of chronic renal failure associated with spinal cord injury.

脊髄損傷 (脊損) 患者にとって腎障害は致命的な合併症であり重要な問題のひとつである. 今回, 脊損腎不全患者8名における腎不全の特徴, 透析上の問題点を検討した.透析導入までの期間は, 16.4年であった. 導入時平均クレアチニン値は7.2±2.5mg/dlと低値でありクレアチニンクリアランスとの解離を認める症例が存在し, 導入時期決定に注意を要する. 導入時HCO3-は平均10.9mEq/l, Naは122.1mEq/lと高度の体液異常を認めることが特徴である. 導入理由として消化器症状が全例に, 高度体液異常を5例に, 心不全を3例に認め, 緊急導入となることが多い. 導入前後を通じて褥創手術を5名が経験しており, 3例は菌血症に陥っている. 導入期に肺炎を2名が併発しており尿路感染症とともに感染症対策が重要である. 導入期は, 体液異常, 感染症, 栄養不良等の理由から死亡率が高く導入期はより慎重な対応が必要となる. VURは2例3腎に見るのみであったが, 水腎は6例11腎に認めた. 神経因性膀胱による尿路障害とこれに伴う尿路感染症が脊髄損傷, 慢性腎不全の原因・増悪因子となるが, 全例に蛋白尿を認め糸球体障害の合併が疑われ, 剖検例ではVURの有無にかかわらず巣状糸球体硬化病変を認めた.脊髄損傷腎不全患者は特異な疾患群といえこれらの特徴を認識して対応する必要がある.