Recovery from rituximab-associated persistent hypogammaglobulinaemia in children with nephrotic syndrome.

BACKGROUND AND HYPOTHESIS: There are limited data on the long-term outcomes and risk factors for non-recovery after development of rituximab (RTX)-associated persistent hypogammaglobulinaemia among children with idiopathic nephrotic syndrome (NS). METHODS: A nationwide Japanese survey was conducted to determine the prognosis of patients with childhood-onset idiopathic NS who developed persistent hypogammaglobulinaemia after RTX administration. Specifically, predictors of IgG level recovery and risk factors for serious infection were examined. RESULTS: The cohort comprised 118 patients (66.1% boys; median age at initial RTX administration, 7.5 years). Among the 121 patients diagnosed with persistent hypogammaglobulinaemia, only 31 (26.3%) recovered within a median observation period of 2.8 years; approximately 70% of patients continued to exhibit persistent hypogammaglobulinaemia. Among the patients who recovered from hypogammaglobulinaemia, the median time to recovery was 14.1 months. Patients with a history of steroid-resistant NS were less likely to recover from persistent hypogammaglobulinaemia (hazard ratio, 0.28; 95% CI, 0.09-0.87). In addition, of the 118 eligible patients, 18 (15.3%) developed serious infections requiring hospitalization, and the main risk factor for infection during hypogammaglobulinaemia was agranulocytosis (a well-known adverse effect of RTX in children). CONCLUSIONS: A significant portion of patients with RTX-associated persistent hypogammaglobulinaemia did not exhibit recovery even after 1 year. Moreover, the data indicate that patients with a history of steroid-resistant NS have a significantly lower probability of recovering from this condition. Agranulocytosis under hypogammaglobulinaemia was significantly associated with an elevated risk of serious infections.

Barriers to conservative kidney management for Japanese healthcare professionals involved in the treatment of end-stage renal disease.

BACKGROUND: Conservative kidney management (CKM) is a treatment alternative for patients with end-stage kidney disease (ESKD). Despite the increasing population of elderly dialysis patients in Japan, CKM is not as readily available compared with that in North America and Europe. Therefore, it is important to clarify the barriers to CKM in Japan. METHODS: We interviewed 11 experts to explore their beliefs and issues regarding CKM. Based on the interviews, we categorized the CKM barriers into eight categories and created a 24-item questionnaire. A questionnaire survey was conducted among 112 medical professionals involved in ESKD management. To investigate the types of barriers, we conducted an exploratory factor analysis using the questionnaire results. RESULTS: Responses were obtained from 53 (47.3%) of 112 subjects (18 doctors, 29 nurses, 6 clinical engineers), with 94.3% considering CKM as a treatment option for ESKD. Factor analysis categorized the questions into the following: (1) Lack of palliative care experience, (2) Ethics and responsibility, (3) Patient's problem, (4) Dialog with patients and families, and (5) Lack of support system. Regarding barriers to CKM, "lack of experience in palliative care" and "lack of support system" scored the highest, and "ethics and responsibility" scored the lowest. CONCLUSIONS: Barriers to CKM may be classified into five factors, with "lack of experience in palliative care" and "lack of support system" being the important barriers to overcome. Additionally, most healthcare professionals consider CKM as the fourth option for renal replacement therapy.

Protocol for the nationwide registry of patients with polycystic kidney disease: japanese national registry of PKD (JRP).

BACKGROUND: Autosomal dominant polycystic kidney disease (ADPKD) and autosomal recessive polycystic kidney disease (ARPKD) are major genetic polycystic kidney diseases that can progress to end-stage kidney disease (ESKD). Longitudinal data on the clinical characteristics associated with clinical outcomes in polycystic kidney disease (PKD), including the development of ESKD and cardiovascular disease (CVD) are lacking in Japan. To address this unmet need the authors are establishing a novel, web-based, Nationwide Cohort Registry Study-the Japanese Registry of PKD (JRP). METHODS: The JRP is a prospective cohort study for ADPKD (aim to recruit n = 1000 patients), and both a retrospective and prospective study for ARPKD (aim to recruit n = 100). In the prospective registry, patients will be followed-up for 10 years every 6 months and 12 months for patients with ADPKD and ARPKD, respectively. Data collection will be recorded on Research Electronic Data Capture (REDCap) starting on April 1, 2024, with recruitment ending on March 31, 2029. (jRCT 1030230618). RESULTS: Data to be collected include: baseline data, demographics, diagnostic and genetic information, radiological and laboratory findings, and therapeutic interventions. During follow-up, clinical events such as development of ESKD, hospitalization, occurrence of extra kidney complications including CVD events, and death will be recorded, as well as patient-reported health-related quality of life for patients with ADPKD. CONCLUSIONS: The JRP is the first nationwide registry study for patients with ADPKD and ARPKD in Japan, providing researchers with opportunities to advance knowledge and treatments for ADPKD and ARPKD, and to inform disease management and future clinical practice.

Public support for patients with intractable diseases in Japan: impact on clinical indicators from nationwide registries in patients with autosomal dominant polycystic kidney disease.

BACKGROUND: Clinical practice guidelines recommend antihypertensive and tolvaptan therapies for patients with autosomal dominant polycystic kidney disease (ADPKD) in Japan. However, tolvaptan therapy may pose an economic burden. The Japanese Ministry of Health, Labour and Welfare supports patients with intractable diseases. This study aimed to confirm the impact of the intractable disease system in Japan on the clinical treatment of ADPKD. METHODS: We analyzed the data of 3768 patients with ADPKD having a medical subsidy certificate from the Japanese Ministry of Health, Labour and Welfare in 2015-2016. The following quality indicators were use: the adherence rate to the 2014 clinical practice guideline for polycystic kidney disease (prescription rates of antihypertensive agents and tolvaptan in this cohort) and the number of Japanese patients with ADPKD nationwide started on renal replacement therapy in 2014 and 2020. RESULTS: Compared with new applications from 2015 to 2016, the prescription rates of antihypertensives and tolvaptan for the indicated patients at the 2017 renewal application increased by 2.0% (odds ratio = 1.41, p = 0.008) and 47.4% (odds ratio = 10.1, p > 0.001), respectively. These quality indicators improved with antihypertensive treatment, especially in patients with chronic kidney disease stages 1-2 (odds ratio = 1.79, p = 0.013) and in those aged < 50 years (odds ratio = 1.70, p = 0.003). The number of patients with ADPKD who were started on renal replacement therapy in Japan decreased from 999 in 2014 to 884 in 2020 in the nationwide database (odds ratio = 0.83, p < 0.001). CONCLUSIONS: The Japanese public intractable disease support system contributes to improvement of ADPKD treatment.

Chapter 1: Evaluation of kidney function in patients undergoing anticancer drug therapy, from clinical practice guidelines for the management of kidney injury during anticancer drug therapy 2022.

The prevalence of CKD may be higher in patients with cancer than in those without due to the addition of cancer-specific risk factors to those already present for CKD. In this review, we describe the evaluation of kidney function in patients undergoing anticancer drug therapy. When anticancer drug therapy is administered, kidney function is evaluated to (1) set the dose of renally excretable drugs, (2) detect kidney disease associated with the cancer and its treatment, and (3) obtain baseline values for long-term monitoring. Owing to some requirements for use in clinical practice, a GFR estimation method such as the Cockcroft-Gault, MDRD, CKD-EPI, and the Japanese Society of Nephrology's GFR estimation formula has been developed that is simple, inexpensive, and provides rapid results. However, an important clinical question is whether they can be used as a method of GFR evaluation in patients with cancer. When designing a drug dosing regimen in consideration of kidney function, it is important to make a comprehensive judgment, recognizing that there are limitations regardless of which estimation formula is used or if GFR is directly measured. Although CTCAEs are commonly used as criteria for evaluating kidney disease-related adverse events that occur during anticancer drug therapy, a specialized approach using KDIGO criteria or other criteria is required when nephrologists intervene in treatment. Each drug is associated with the different disorders related to the kidney. And various risk factors for kidney disease associated with each anticancer drug therapy.

Changes in Metabolomic Profiles Induced by Switching from an Erythropoiesis-Stimulating Agent to a Hypoxia-Inducible Factor Prolyl Hydroxylase Inhibitor in Hemodialysis Patients: A Pilot Study.

Hypoxia-inducible factor prolyl hydroxylase inhibitors (HIF-PHIs) are a new class of medications for managing renal anemia in patients with chronic kidney disease (CKD). In addition to their erythropoietic activity, HIF-PHIs exhibit multifaceted effects on iron and glucose metabolism, mitochondrial metabolism, and angiogenesis through the regulation of a wide range of HIF-responsive gene expressions. However, the systemic biological effects of HIF-PHIs in CKD patients have not been fully explored. In this prospective, single-center study, we comprehensively investigated changes in plasma metabolomic profiles following the switch from an erythropoiesis-stimulating agent (ESA) to an HIF-PHI, daprodustat, in 10 maintenance hemodialysis patients. Plasma metabolites were measured before and three months after the switch from an ESA to an HIF-PHI. Among 106 individual markers detected in plasma, significant changes were found in four compounds (erythrulose, n-butyrylglycine, threonine, and leucine), and notable but non-significant changes were found in another five compounds (inositol, phosphoric acid, lyxose, arabinose, and hydroxylamine). Pathway analysis indicated decreased levels of plasma metabolites, particularly those involved in phosphatidylinositol signaling, ascorbate and aldarate metabolism, and inositol phosphate metabolism. Our results provide detailed insights into the systemic biological effects of HIF-PHIs in hemodialysis patients and are expected to contribute to an evaluation of the potential side effects that may result from long-term use of this class of drugs.

Role of the new bioimpedance monitoring device (Seca®) in assessing dry weight in hemodialysis patients.

BACKGROUND: In recent years, bioimpedance analysis has come to be widely used in clinical practice for dialysis patients, but there is not sufficient consensus on its significance. We aimed to examine the merits of performing bioimpedance analysis in addition to conventional evaluation methods for dry weight such as measuring human atrial natriuretic peptide (hANP), blood pressure, and cardiothoracic ratio in patients on chronic hemodialysis. METHODS: Body composition of 78 hemodialysis patients was performed by using a new and more accurate segmental multifrequency bioimpedance analysis device (Seca® medical body composition analyzer 525, Seca GmbH & Co. KG, Hamburg, Germany). Laboratory data including hANP at post-dialysis and demographic profile were collected. Statistical analysis was performed with SPSS software. RESULTS: Mean age of the patients was 66.9 ± 12.6 years and 80.8% were males. Mean value of hANP and the ratio of extracellular water to total body water (ECW/TBW) were 61.4 ± 36.4 pg/mL and 46.1 ± 3.9%, respectively. The calculated ECW/TBW cutoff point for hANP > 50 pg/mL was 45.0%, with sensitivity of 74.4% and specificity of 64.7%. Patients with an ECW/TBW of more than 45% and hANP value of > 50 pg/mL had a higher blood pressure and cardiothoracic ratio on chest X-ray examination. CONCLUSIONS: Our results suggest that the ratio of extracellular water to total body water of more than 45% and hANP value of ≥ 50 pg/mL were overhydrated in chronic hemodialysis patients. Whether monitoring levels of these parameters has a role in the outcome including patients' survival and cardiovascular events requires further study.

Phenotypic differences of mutation-negative cases in Gitelman syndrome clinically diagnosed in adulthood.

Gitelman syndrome (GS), an autosomal recessive kidney disorder, is characterized by hypokalemia, hypomagnesemia, hypocalciuria, and metabolic alkalosis. Generally, diagnosis is made in school-aged children but multiple cases have been diagnosed in adulthood. This study examines the phenotypic differences between genetically confirmed cases and mutation-negative cases in adults. A comprehensive screening of 168 genes, including GS-related genes, was performed for 84 independent individuals who were referred to our institute with a clinical diagnosis of GS. The cases of pseudo-Bartter syndrome (BS)/GS because of diuretic abuse or other causes, which was determined based on patients' medical records, were excluded during registration. Of these 70 eligible cases for analysis, 27 (38.6%) had genetic confirmation of GS, while 37 (52.8%) had no known variants associated with GS and were considered to be unsolved cases. Note that unsolved cases comprised older, mostly female, individuals with decreased kidney function and multiple basic features of GS. The phenotype of unsolved cases is similar to that of pseudo BS/GS cases, although these cases were excluded in advance. However, the genetic and autoimmune profiles of these unsolved cases have not yet been investigated to date. Therefore, these cases may be categorized into new disease groups.

Deletion of Alox15 improves kidney dysfunction and inhibits fibrosis by increased PGD2 in the kidney.

BACKGROUND: Lipid-metabolizing enzymes and their metabolites affect inflammation and fibrosis, but their roles in chronic kidney disease (CKD) have not been completely understood. METHODS: To clarify their role in CKD, we measured the mRNA levels of major lipid-metabolizing enzymes in 5/6 nephrectomized (Nx) kidneys of C57BL/6 J mice. Mediator lipidomics was performed to reveal lipid profiles of CKD kidneys. RESULTS: In 5/6 Nx kidneys, both mRNA and protein levels of Alox15 were higher when compared with those in sham kidneys. With respect to in situ hybridization, the mRNA level of Alox15 was higher in renal tubules of 5/6 Nx kidneys. To examine the role of Alox15 in CKD pathogenesis, we performed 5/6 Nx on Alox15-/- mice. Alox15-/- CKD mice exhibited better renal functions than wild-type mice. Interstitial fibrosis was also inhibited in Alox15-/- CKD mice. Mediator lipidomics revealed that Alox15-/- CKD mouse kidneys had significantly higher levels of PGD2 than the control. To investigate the effects of PGD2 on renal fibrosis, we administered PGD2 to TGF-ß1-stimulated NRK-52E cells and HK-2 cells, which lead to a dose-dependent suppression of type I collagen and αSMA in both cell lines. CONCLUSION: Increased PGD2 in Alox15-/- CKD mouse kidneys could inhibit fibrosis, thereby resulting in CKD improvement. Thus, Alox15 inhibition and PGD2 administration may be novel therapeutic targets for CKD.

Assessing urine ammonium concentration by urine osmolal gap in chronic kidney disease.

Acidemia is one of the risk factors for end-stage kidney disease and increases the mortality rate of patients with chronic kidney disease (CKD). Although urinary ammonium (U-NH4 + ) is the crucial component of renal acid excretion, U-NH4 + concentration is not routinely measured. To estimate U-NH4 + , urine osmolal gap (UOG = urine osmolality - [2(Na+ + K+ ) + urea + glucose]) is calculated and the formula (U-NH4 +  = UOG/2) has traditionally been used. However, the usefulness of this formula is controversial in CKD patients. We assessed the relationship between U-NH4 + and UOG in patients with CKD. Blood and spot urine samples were collected in 36 patients who had non-dialysis-dependent CKD. The mean ± SD age of patients was 72.0 ± 14.8 years, and the mean ± SD serum creatinine and U-NH4 + were 2.7 ± 2.3 mg/dl and 9.3 ± 9.2 mmol/L, respectively. A significant relationship was found between UOG/2 and U-NH4 + (r = .925, p < .0001). U-NH4 + estimated using the UOG was on average higher by 4.7 mmol/L than the measured one. Our results suggested that UOG could be a useful tool in clinical settings, especially in patients with moderate to severe CKD.

Renal TNFα activates the WNK phosphorylation cascade and contributes to salt-sensitive hypertension in chronic kidney disease.

The inappropriate over-activation of the with-no-lysine kinase (WNK)-STE20/SPS1-related proline/alanine-rich kinase (SPAK)-sodium chloride cotransporter (NCC) phosphorylation cascade increases sodium reabsorption in distal kidney nephrons, resulting in salt-sensitive hypertension. Although chronic kidney disease (CKD) is a common cause of salt-sensitive hypertension, the involvement of the WNK phosphorylation cascade is unknown. Moreover, the effect of immune systems on WNK kinases has not been investigated despite the fact that immune systems are important for salt sensitivity. Here we demonstrate that the protein abundance of WNK1, but not of WNK4, was increased at the distal convoluted tubules in the aristolochic acid nephropathy mouse model of CKD. Accordingly, the phosphorylation of both SPAK and NCC was also increased. Moreover, a high-salt diet did not adequately suppress activation of the WNK1-SPAK-NCC phosphorylation cascade in this model, leading to salt-sensitive hypertension. WNK1 also was increased in adenine nephropathy, but not in subtotal nephrectomy, models of CKD. By comparing the transcripts of these three models focusing on immune systems, we hypothesized that tumor necrosis factor (TNF)-α regulates WNK1 protein expression. In fact, TNF-α increased WNK1 protein expression in cultured renal tubular cells by reducing the transcription and protein levels of NEDD4-2 E3-ligase, which degrades WNK1 protein. Furthermore, the TNF-α inhibitor etanercept reversed the reduction of NEDD4-2 expression and upregulation of the WNK1-SPAK-NCC phosphorylation cascade in distal convoluted tubules in vivo in the aristolochic acid nephropathy model. Thus, salt-sensitive hypertension is induced in CKD via activation of the renal WNK1- SPAK-NCC phosphorylation cascade by TNF-α, reflecting a link with the immune system.

Genetics May Predict Effectiveness of Tolvaptan in Autosomal Dominant Polycystic Kidney Disease.

BACKGROUND: Tolvaptan is the only therapeutic drug for autosomal dominant polycystic kidney disease (ADPKD). The influence of mutations in polycystic kidney disease 1 and 2 genes (PKD1 and PKD2) on the treatment effects of tolvaptan is not well documented in the literature. METHODS: We retrospectively evaluated the relationship between genotype and the efficacy of tolvaptan in 18 patients with ADPKD who had been treated at Toranomon Hospital and undergone genetic testing between April 2016 and February 2020. RESULTS: The annual change in estimated glomerular filtration rate (ΔeGFR/y) from before to after tolvaptan was from a median of -5.5 to -2.5 mL/min/1.73 m2 in the PKD1 truncating group, -3.3 to -2.4 mL/min/1.73 m2 in the PKD1 non-truncating group, -3.1 to -1.6 mL/min/1.73 m2 in the PKD2 group, and -1.9 to -2.6 mL/min/1.73 m2 in the group with no PKD1/2 mutation. The median degrees of improvement of ΔeGFR/y were 2.5 (45%), 0.4 (10%), 0.6 (28%), and -0.7 (-37%) mL/min/1.73 m2, respectively. Compared with the group of patients with any PKD1/2 mutation, the group with no PKD1/2 mutation showed significantly less improvement in ΔeGFR/y with tolvaptan (0.6 vs. -0.7 mL/min/1.73 m2, respectively; p = 0.01) and significantly less improvement in the annual rate of increase in total kidney volume (TKV) with tolvaptan (-6.7 vs. -1.1%, respectively; p = 0.02). CONCLUSION: Patients with ADPKD and no PKD1/2 mutation showed less improvement in ΔeGFR/y and the annual rate of increase in TKV with tolvaptan. Detecting PKD1/2 mutations may be useful for predicting the effectiveness of tolvaptan.

Serial measurement of electrolyte and citrate concentrations in blood-primed continuous hemodialysis circuits during closed-circuit dialysis.

BACKGROUND: For continuous renal replacement therapy in small infants, due to the large extracorporeal volume involved, blood priming can be necessary to prevent hypotension and hemodilution. Because packed red blood cells (RBCs) have high levels of potassium and citrate, closed-circuit dialysis is often performed. We assessed the metrics of closed-circuit dialysis and serial citrate concentration changes. METHODS: We performed dialysis of closed circuits primed with expired human packed RBC solution and 5% albumin. Blood and dialysate flow rates were 70 and 33.3 mL/min, respectively. The extracorporeal volume was 70 mL. We measured pH, electrolytes, and citrate in the closed circuit every 3 min for 15 min. We also assessed the adequacy of closed-circuit dialysis using the formula: [dialysate flow rate (mL/min) × time of dialysis (min)]/extracorporeal volume (mL) and we assessed the correlation between citrate and ionized calcium concentrations. RESULTS: To reach normal concentrations of sodium, potassium, and chloride, 2.4 times as much dialysate fluid as extracorporeal volume was needed. In contrast, for ionized calcium, bicarbonate, and citrate, 3.8 times as much dialysate fluid as extracorporeal volume was required. By simple linear regression analysis, the concentration of citrate was significantly correlated with that of ionized calcium. CONCLUSIONS: For closed-circuit dialysis using an RBC solution, the formula [dialysate flow rate (mL/min) × time of dialysis (min)]/extracorporeal volume (mL) would be a better parameter to estimate efficacy, compared with other metrics. Additionally, the citrate concentration can be readily estimated from the ionized calcium concentration during closed-circuit dialysis.

Association between chronic kidney disease and mortality in stage IV cancer.

BACKGROUND: Chronic kidney disease (CKD) is known to be associated with cancer mortality. However, no study has considered the well-known cancer prognostic factors, ECOG Performance Status (PS) and cancer treatment, as confounding factors. We assessed the independent relationship between CKD and cancer death in stage IV cancer patients. METHODS: In this retrospective observational study, we included stage IV cancer patients diagnosed from 2009 to 2014 in a single center. We collected baseline clinical and laboratory variables, and cancer-specific variables, and assessed the presence of CKD. Our primary outcome was all-cause mortality. The secondary outcome was cancer-specific mortality and site-specific cancer mortality. RESULTS: Among 961 eligible stage IV cancer patients (median age 69 years, 51.8% male), 150 patients had CKD. During follow-up (median 9.8 months), 638 patients died, of whom 526 patients died from cancer. After adjusting for prognostic variables, including ECOG PS and cancer treatment, all-cause mortality and cancer-specific mortality were significantly higher in CKD patients than in non-CKD patients (HR 1.41, 95% CI 1.13-1.77 and HR 1.43, 95% CI 1.12-1.83, respectively). In patients with breast and kidney and urinary tract cancers, CKD was associated with a significantly increased risk of death (HR 7.01, 95% CI 1.47-33.4 and HR 3.33, 95% CI 1.42-7.78, respectively). CONCLUSIONS: CKD at the time of stage IV cancer diagnosis was associated with all-cause mortality and cancer-specific mortality. Moreover, the association between CKD and cancer-specific death was site specific for breast cancer and kidney and urinary tract cancer.

Genotype-Clinical Correlations in Polycystic Kidney Disease with No Apparent Family History.

BACKGROUND: Genetic characteristics of polycystic kidney disease (PKD) patients without apparent family history were reported to be different from those with a positive family history. However, the clinical course of PKD patients with no apparent family history is not well documented in the literature. METHODS: We evaluated the relationship between genotype and the clinical course of 62 PKD patients with no apparent family history. RESULTS: The annual decline of renal function was faster in the patients with PKD1/PKD2 mutation (PKD1 truncating [-3.08; 95% CI -5.30 to -0.87, p = 0.007], PKD1 nontruncating [-2.10; -3.82 to -0.38, p = 0.02], and PKD2 [-2.31; -4.40 to -0.23, p = 0.03]) than in the other patients without PKD1/PKD2 mutation. Similar results were obtained after adjustment for gender, age, estimated glomerular filtration rate (eGFR), height-adjusted total kidney volume (TKV), and mean arterial pressure (MAP). There was no significant difference in the annual decline of renal function among the different PKD1/PKD2 groups, but Kaplan-Meier analysis showed that progression to eGFR < 15 mL/min/1.73 m2 was significantly faster in PKD1 truncating group (p = 0.05). The annual rate of TKV increase was larger in the patients with PKD1/PKD2 mutation (PKD1 truncating [4.63; 95% CI 0.62-8.64, p = 0.03], PKD1 nontruncating [3.79; 0.55-7.03, p = 0.02], and PKD2 [2.11; -1.90 to 6.12, p = 0.29]) than in the other patients without PKD1/PKD2 mutation. Similar results were obtained after adjustment for gender, age, eGFR, and MAP. CONCLUSION: Detection of PKD1/PKD2 mutation, especially PKD1 truncating, is useful for predicting the renal outcome and rate of TKV increase in PKD patients with no apparent family history.

[Transplantation-associated thrombotic microangiopathy confirmed by renal biopsy].

An eight-year-old girl with myelodysplastic syndrome (refractory cytopenia) received a bone marrow transplant (BMT) from an unrelated donor because of immunosuppressive therapy failure. Following administration of foscarnet for cytomegalovirus reactivation at day40 post-BMT, serum creatinine increased, and proteinuria, hematuria, and hypertension gradually exacerbated and became prolonged. However, neither schistocytosis nor other organ damage was evident. At six months post-BMT, renal biopsy revealed diffuse glomerular damage with glomerular lobulation, a double contour of the glomerular basement membrane, erythrocyte congestion and thrombi in the glomerular endocapillaries, and mesangiolysis, confirming the diagnosis of transplantation-associated thrombotic microangiopathy (TA-TMA). We initiated strict controls regarding fluid balance, salt intake, and blood pressure. The patient's renal function improved 10 months post-BMT. TA-TMA often presents as non-specific symptoms, making diagnosis difficult. In cases of post-transplant renal damage, TA-TMA should be differentiated regardless of whether specific symptoms such as hemolytic anemia and other organ failure are evident, and a renal biopsy should, therefore, be considered.

Decreased levels of inflammatory cytokines in immunoglobulin-resistant Kawasaki disease after plasma exchange.

The pathogenesis of coronary artery aneurysm (CAA) formation in Kawasaki disease (KD) remains unknown. However, inflammatory cytokines are thought to play an important role in KD. Patients with intravenous immunoglobulin (IVIG)-resistant KD are more likely to develop CAA. For such refractory patients, steroids and emerging infliximab (IFX) are used; however, further verification is required for their efficacy and safety. Plasma exchange (PE), which removes various inflammatory cytokines, has been used in Japan for over 15 years to prevent CAA in IVIG-resistant KD patients. The sequential change in inflammatory cytokines during the time course of PE has yet to be investigated. In this study, we measured plasma levels of 13 cytokines in nine children with IVIG-resistant KD before the start of PE (day 0: D0), as well as at 1 or 2 days (D1/2), and 4 or 5 days (D4/5) after starting PE. The median age of onset was 8 months (range: 3-53 months). Before PE, patients were treated with IVIG (median dose: 4 g/kg, range: 3-4 g/kg). The median starting period of PE was 8 days after the onset of fever (range: 6-21 days), while its duration was 3 days (range: 2-5 days). Among the 13 cytokines, interleukin-6, tumor necrosis factor-α, tumor necrosis factor receptor I (TNFR1), TNFR2, granulocyte colony-stimulating factor, and IL-17 were significantly lower at D4/5 compared with D0 and/or D1/2, reflecting the potential central efficacy of PE. While three patients developed moderate CAA, their condition regressed within 1 year. The removal of inflammatory cytokines could be the central efficacy of PE against refractory KD.

Rituximab treatment combined with methylprednisolone pulse therapy and immunosuppressants for childhood steroid-resistant nephrotic syndrome.

BACKGROUND: Calcineurin inhibitors (CIs) with/without intravenous methylprednisolone pulse therapy (MPT) constitute the standard treatment for childhood-onset, steroid-resistant nephrotic syndrome (SRNS). However, some patients fail to achieve remission. We treated SRNS patients resistant to CIs and MPT with additional rituximab combined with MPT and immunosuppressive agents. METHODS: Ten patients (aged 2-14 years) with CI- and MPT-resistant SRNS were enrolled. Patients were administered rituximab (1-4 doses; 375 mg/m(2)) followed by MPT (30 mg/kg/day of methylprednisolone for 3 consecutive days) once every 2-4 weeks until complete remission (CR). We analyzed clinical outcome and safety. RESULTS: Six patients received a single dose of rituximab, 2 received two doses, and 2 received four doses. Seven patients achieved CR, 1 achieved partial remission, and 2 showed no response. Although 2 patients with no response progressed to end-stage renal failure, 7 patients with CR preserved normal renal function without proteinuria at the last observation. There were two serious adverse events. CONCLUSIONS: Additional rituximab combined with conventional MPT and immunosuppressive agents is a promising option for overcoming refractory SRNS. Aggressive B cell suppression by rituximab may ameliorate resistance to conventional treatments and a cocktail of other immunosuppressive agents, such as CIs, MMF, mizoribine, may be beneficial. However, as intense immunosuppression may cause serious adverse events, further evaluation is necessary.

Successful remission induced by plasma exchange combined with leukocytapheresis against refractory systemic juvenile idiopathic arthritis.

Systemic juvenile idiopathic arthritis (sJIA) is an inflammatory cytokine-related disorder associated with overproduction of interleukin (IL)-6, IL-1ß, and IL-18. Macrophage activation syndrome (MAS) is a critical and lethal complication of sJIA. Therefore, prompt induction of remission in the active phase of sJIA is important for prevention of MAS. However, treatment of corticosteroid-resistant sJIA is still challenging. We propose a new strategy to induce remission in the active phase of sJIA. A 7-year-old boy with new-onset sJIA was treated with oral prednisolone, methylprednisolone pulse therapy, and parenteral cyclosporine, but he continuously showed remittent high fever, arthralgia, skin rash, and elevation of inflammatory markers, including hyperferritinemia. Because of impending MAS, plasma exchange was started, but he was resistant to plasma exchange. Therefore, we combined leukocytapheresis with PE. After five PE and two leukocytapheresis sessions, he finally achieved remission in accordance with a reduction in inflammatory cytokines. Elevated serum tumor necrosis factor-α, interferon-γ, and IL-12 levels returned to normal 10 days after initiating plasma exchange combined with leukocytapheresis, with a reduction in white blood cell count. In conclusion, plasma exchange combined with leukocytapheresis is a new alternative option to induce remission for patients with methylprednisolone pulse therapy- or cyclosporine-refractory sJIA.