Patient classification and outcome prediction in IgA nephropathy.

OBJECTIVE: IgA Nephropathy (IgAN) is a common kidney disease which may entail renal failure, known as End Stage Kidney Disease (ESKD). One of the major difficulties dealing with this disease is to predict the time of the long-term prognosis for a patient at the time of diagnosis. In fact, the progression of IgAN to ESKD depends on an intricate interrelationship between clinical and laboratory findings. Therefore, the objective of this work has been the selection of the best data mining tool to build a model able to predict (I) if a patient with a biopsy proven IgAN will reach ESKD and (II) if a patient will reach the ESKD before or after 5 years. MATERIAL AND METHODS: The largest available cohort study worldwide on IgAN has been used to design and compare several data-driven models. The complete dataset was composed of 1174 records collected from Italian, Norwegian, and Japanese IgAN patients, in the last 30 years. The data mining tools considered in this work were artificial neural networks (ANNs), neuro fuzzy systems (NFSs), support vector machines (SVMs), and decision trees (DTs). A 10-fold cross validation was used to evaluate unbiased performances for all the models. RESULTS: An extensive model comparison based on accuracy, precision, recall, and f-measure was provided. Overall, the results indicate that ANNs can provide superior performance compared to the other models. The ANN for time-to-ESKD prediction is characterized by accuracy, precision, recall, and f-measure greater than 90%. The ANN for ESKD prediction has accuracy greater than 90% as well as precision, recall, and f-measure for the class of patients not reaching ESKD, while precision, recall, and f-measure for the class of patients reaching ESKD are slightly lower. The obtained model has been implemented in a Web-based decision support system (DSS). CONCLUSIONS: The extraction of novel knowledge from clinical data and the definition of predictive models to support diagnosis, prognosis, and therapy is becoming an essential tool for researchers and clinical practitioners in medicine. The proposed comparative study of several data mining models for the outcome prediction in IgAN patients, using a large dataset of clinical records from three different countries, provides an insight into the relative prediction ability of the considered methods applied to such a disease.

Targeted IgA Fc receptor I (FcαRI) therapy in the early intervention and treatment of pristane-induced lupus nephritis in mice.

The Fc receptor I for IgA (FcαRI) down-regulates humoral immune responses and modulates the risk of autoimmunity. This study aimed to investigate whether FcαRI targeting can affect progression of pristine-induced lupus nephritis. In the first experiment (early intervention), four groups of animals were evaluated: untreated FcαRI/FcRγ transgenic (Tg) mice and Tg mice administered control antibody (Ctr Fab), saline and anti-FcαRI Fab [macrophage inflammatory protein (MIP)-8a], respectively, three times a week for 29 weeks, after being injected once intraperitoneally with 0·5 ml pristane. In the second experiment, antibody injection started after the onset of nephritis and was carried out for 2 months, with similar groups as described above. MIP-8a improved proteinuria, decreased the amounts of glomerular injury markers, serum interleukin (IL)-6, IL-1 and monocyte chemoattractant protein (MCP)-1, and F4/80 macrophages in the interstitium and glomeruli, in both experiments. When MIP-8a was used as early intervention, a decrease in mouse serum anti-nuclear antibody (ANA) titres and reduced deposition of immunoglobulins in glomeruli were observed. This effect was associated with reduced serum titres of immunoglobulin (Ig)G2a but not IgG1, IgG2b and IgG3. Furthermore, pathological analysis showed lower glomerular activity index and less fibronectin in MIP-8a treated mice. This study suggests that FcαRI targeting could halt disease progression and lupus activation by selective inhibition of cytokine production, leucocyte recruitment and renal inflammation. Our findings provide a basis for the use of FcαRI as a molecular target for the treatment of lupus.

Urinary podocalyxin is an early marker for podocyte injury in patients with diabetes: establishment of a highly sensitive ELISA to detect urinary podocalyxin.

AIMS/OBJECTIVE: Nephropathy, a major complication of diabetes, is the leading cause of end-stage renal disease. Recent studies have demonstrated that podocyte injury is involved in the onset of and progression to renal insufficiency. Here, we describe a novel, highly sensitive ELISA for detecting urinary podocalyxin, a glycoconjugate on the podocyte apical surface that indicates podocyte injury, particularly in the early phase of diabetic nephropathy. METHODS: Urine samples from patients with glomerular diseases (n = 142) and type 2 diabetes (n = 71) were used to quantify urinary podocalyxin by ELISA. Urine samples were obtained from 69 healthy controls for whom laboratory data were within normal values. Podocalyxin was detected in urine by immunofluorescence, immunoelectron microscopy and western blotting. RESULTS: Morphologically, urinary podocalyxin was present as a vesicular structure; western blotting showed it as a positive band at 165-170 kDa. Levels of urinary podocalyxin were elevated in patients with various glomerular diseases and patients with diabetes. In patients with diabetes, urinary podocalyxin was higher than the cut-off value in 53.8% patients at the normoalbuminuric stage, 64.7% at the microalbuminuric stage and 66.7% at the macroalbuminuric stage. Positive correlations were observed between urinary podocalyxin levels and HbA(1c), urinary ß(2) microglobulin, α(1) microglobulin and urinary N-acetyl-ß-D-glucosaminidase, although urinary podocalyxin levels were not correlated with other laboratory markers such as blood pressure, lipid level, serum creatinine, estimated GFR or proteinuria. CONCLUSIONS/INTERPRETATION: Urinary podocalyxin may be a useful biomarker for detecting early podocyte injury in patients with diabetes.

Asymmetric dimethylarginine: a novel cardiovascular risk factor in end-stage renal disease.

OBJECTIVE: This cross-sectional study explored the association between carotid intima-media thickness (CIMT) and the oxidative stress markers asymmetric dimethylarginine (ADMA) and homo cysteine in patients with end-stage renal disease who were on haemodialysis. METHODS: A total of 30 patients undergoing chronic haemodialysis treatment were recruited to this study. Homocysteine and ADMA levels were determined using a fluorescence polarization immunoassay and an enzyme-linked immunosorbent assay, respectively. CIMT was measured as a marker of atherosclerosis using high-resolution ultrasonography and was performed after haemodialysis. RESULTS: Significant positive correlations were found between CIMT and ADMA, and CIMT and duration of haemodialysis. Linear regression analysis showed that ADMA level and age were significant independent determinants of CIMT, whereas homo cysteine was not. CONCLUSIONS: The relationship demonstrated between plasma ADMA and carotid artery thickening suggests that ADMA may be a novel marker of atherosclerosis in patients on haemodialysis.

Negative regulation of inflammatory responses by immunoglobulin A receptor (FcαRI) inhibits the development of Toll-like receptor-9 signalling-accelerated glomerulonephritis.

Myeloid FcαRI, a receptor for immunoglobulin (Ig)A, mediates cell activation or inhibition depending on the type of ligand interaction, which can be either multivalent or monovalent. Anti-inflammatory signalling is triggered by monomeric targeting using anti-FcαRI Fab or IgA ligand binding, which inhibits immune and non-immune-mediated renal inflammation. The participation of Toll-like receptors (TLRs) in kidney pathology in experimental models and various forms of human glomerular nephritis has been discussed. However, little is known about negative regulation of innate-immune activation. In the present study, we generated new transgenic mice that express FcαRI(R209L) /FcRγ chimeric protein and showed that the monovalent targeting of FcαRI exhibited inhibitory effects in an in vivo model of TLR-9 signalling-accelerated nephritis. Mouse monoclonal anti-FcαRI MIP8a Fab improved urinary protein levels and reduced the number of macrophages and immunoglobulin deposition in the glomeruli. Monovalent targeting using MIP8a Fab attenuates the TLR-9 signalling pathway and is associated with phosphorylation of extracellular signal-related protein kinases [extracellular signal-regulated kinase (ERK), P38, c-Jun N-terminal kinase (JNK)] and the activation of nuclear factor (NF)-κB. The inhibitory mechanism involves recruitment of tyrosine phosphatase Src homology 2 domain-containing phosphatase-1 (SHP-1) to FcαRI. Furthermore, cell transfer studies with macrophages pretreated with MIP8a Fab showed that blockade of FcαRI signalling in macrophages prevents the development of TLR-9 signalling-accelerated nephritis. These results suggest a role of anti-FcαRI Fab as a negative regulator in controlling the magnitude of the innate immune response and a new type of anti-inflammatory drug for treatment of kidney disease.

Significance of glomerular activation of the alternative pathway and lectin pathway in lupus nephritis.

The objective of the present study was to elucidate the association between glomerular complement depositions belonging to the alternative (AP) and lectin (LP) pathways, and clinical findings of lupus nephritis (LN). Immunofluorescence (IF) was performed on 17 LN patients using antibodies against factor B, factor H, properdin, mannose-binding lectin (MBL) and L-ficolin. Compared with factor B/factor H negative patients (n = 9), positive patients (n = 8) showed longer duration of LN (p < 0.05) and more severe interstitial fibrosis (p < 0.05). Eleven patients had properdin deposition in glomeruli, and in three of them, with a duration of LN of less than 1 month, factor B was undetectable. Compared with properdin negative patients (n = 6), positive patients (n = 11) showed significantly higher urinary protein excretion (p < 0.01). MBL/L-ficolin positive patients (n = 11) also had significantly higher urinary protein excretion (p < 0.05) compared with negative patients (n = 6). An independent association was found between glomerular deposition of properdin and that of MBL/L-ficolin (p < 0.01) in addition to factor B/factor H. Traces of glomerular activation of AP and LP reflected the clinical status of LN. It appears that glomerular deposition of each complement component, especially properdin, may be an index of the histological activity of LN.

Severe erosive lesions in the digestive tract of patients with Henoch-Schönlein Purpura (HSP) and its impact on prognosis - presentation of two cases and statistical review of adult-onset Japanese HSP.

INTRODUCTION: Although many pediatric patients with Henoch-Schönlein Purpura (HSP) recover spontaneously, disease activity in adult patients often cannot be controlled by treatment. PURPOSE: To assess the specific signs not formerly considered to be those of uncontrollable adult HSP patients. PATIENTS AND METHODS: Clinical records of 2 adult patients who died during HSP were reviewed and previous reports on HSP were consulted. RESULTS: Both patients had lesions in the digestive tract diagnosed as hemorrhagic erosion in the small intestine and colon. They were elderly and showed renal dysfunction. They died from severe infection after potent immunosuppressive treatment. A univariate analysis showed that age of over 60 years, severe renal symptoms (nephrotic syndrome and/or end-stage renal failure), Birmingham Vasculitis Activity Score (BVAS) of more than 18 points, massive immunosuppression and melena had significantly higher prevalence among patients who died. Multivariate statistical analysis with theoretical quantification analysis II revealed that age of over 60 and severe renal symptoms (nephrotic syndrome and/or end-stage renal failure) contributed to poor prognosis. The presence of melena did not contribute to poor prognosis despite results of the univariate analysis and our clinical impressions. DISCUSSION: In multivariate statistical analysis, melena was selected as a sign of severe erosive lesions in the digestive tract because some of the patients were not examined by fiberscopy. Melena is caused by various lesions in the digestive tract and each of them has different effects on prognosis. CONCLUSION: Elderly HSP patients with severe renal impairment should be carefully treated. Examination of the digestive tract by fiberscopy is recommended when melena is observed in these patients.

Type B insulin resistance syndrome with systemic lupus erythematosus.

Type B insulin resistance syndrome is a rare disease. Auto-antibodies to the insulin receptor frequently appear in the case of systemic lupus erythematosus (SLE). We report herein a case of a 56-year-old man who had presented discoid skin lesions since 1990. He was admitted to the hospital because of unconsciousness and severe hypoglycemia in 2006, and was diagnosed as having Type B insulin resistance syndrome with the presence of insulin receptor antibody. He had frequently repeated hypoglycemic and hyperglycemic episodes in spite of treatment with prednisolone (5 - 10 mg/day), and mild proteinuria of 1.5 g/day was observed. His laboratory findings on admission revealed pancytopenia and positive titer for antinuclear antibody (ANA). From these findings and his past history of skin lesions, we diagnosed him as SLE. We performed renal biopsy and his histological diagnosis was lupus nephritis Class 5 with the findings of podocytic shedding. Prednisolone dosage was increased from 10 to 60 mg/day. Thereafter, his glucose metabolism improved and proteinuria disappeared. The dose of prednisolone was tapered to 30 mg/day without recurrence of hypoglycemia and proteinuria. Early treatment with prednisolone might ameliorate proteinuria and insulin resistance. We experienced a rare case of Type B insulin resistance syndrome with increased activity of SLE, complicated with lupus nephritis. It appears that Type B insulin resistance syndrome should be suspected in differential diagnosis of hypoglycemia in SLE patients.

Long-term effect of modification of dietary protein intake on the progression of diabetic nephropathy: a randomised controlled trial.

AIMS/HYPOTHESIS: There is currently insufficient evidence to recommend a low-protein diet for type 2 diabetic patients with diabetic nephropathy. We assessed whether a low-protein diet could prevent the progression of diabetic nephropathy. METHODS: This was a multi-site parallel randomised controlled trial for prevention of diabetic nephropathy progression among 112 Japanese type 2 diabetic patients with overt nephropathy. It was conducted in Japan from 1 December 1997 to 30 April 2006. The participants were randomly assigned using a central computer-generated schedule to either low-protein diet (0.8 g kg(-1) day(-1)) and normal-protein diet (1.2 g kg(-1) day(-1)), and were followed for 5 years. The participants and investigators were not blinded to the assignment. The primary outcomes were the annual change in estimated GFR and creatinine clearance, the incidence of doubling of serum creatinine and the time to doubling of baseline serum creatinine. RESULTS: The study was completed by 47 (84%) of 56 participants in the low-protein diet group and 41 (73%) of 56 participants in the normal-diet group. During the study period, the difference in mean annual change in estimated GFR between the low-protein diet and the normal-protein diet groups was -0.3 ml min(-1) 1.73 m(-2) (95% CI -3.9, 4.4; p = 0.93). The difference in mean annual change in creatinine clearance between the low-protein diet and the normal-protein diet groups was -0.006 ml s(-1) 1.73 m(-2) (95% CI -0.089, 0.112; p = 0.80). A doubling of serum creatinine was reached in 16 patients of the low-protein group (34.0%), compared with 15 in the normal-protein group (36.6%), the difference between groups being -2.6% (95% CI -22.6, 17.5; p = 0.80). The time to doubling of serum creatinine was similar in both groups (p = 0.66). CONCLUSIONS/INTERPRETATION: It is extremely difficult to get patients to follow a long-term low-protein diet. Although in the low-protein group overall protein intake was slightly (but not significantly) lower, it did not confer renoprotection. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov NCT00448526. FUNDING: Research grant from the Ministry of Health, Labour and Welfare of Japan.

Long-term effects of the oral adsorbent, AST-120, in patients with chronic renal failure.

The oral adsorbent AST-120 has been widely used in Japan to delay the initiation of dialysis therapy in patients with chronic renal failure. This study evaluated the long-term effects of AST-120 in patients with chronic renal failure who had not previously undergone dialysis. One hundred out-patients were prospectively enrolled and prescribed 6 g/day oral AST-120 for >or= 1 year. The clinical effectiveness of AST-120 was evaluated by comparing changes in the slope of the reciprocal serum creatinine-time plot (1/sCr slope) before and after AST-120 administration. The 1/sCr slope improved significantly after >or= 1 year of AST-120 treatment and greatest improvement was observed in patients with the longest AST-120 administration period (> 30 months). The results suggest that long-term treatment with AST-120 may be beneficial for chronic renal failure patients in the pre-dialysis stage.

Tubular epithelial cells have the capacity to transdifferentiate into CD68-positive macrophage-like cells by oxidative stress.

OBJECTIVE: The present study was intended to assess transdifferentiation from tubular epithelial cells to macrophage- like cells. METHODS: Puromycin aminonucleoside nephrotic rats were sacrificed at days 4, 8, 24 and 112. We immunohistochemically evaluated CD68, CD163, and cytokeratin AE1/AE3, known as markers for macrophages and tubular epithelial cells. Nitrotyrosine, gp91(phox) and Rac 1 expressions was also analyzed. CD68 expression in cultured murine proximal tubular epithelial cells (mProx) stimulated by crude and pure BSA was examined by flow cytometry and immunofluorescence. RESULTS: The tubular CD68-positive cells were observed on day 112. Immunoelectronmicroscopy revealed that some CD68-positive cells showed brush borders on the cell membrane and some of cytokeratin-positive tubular cells also expressed CD163 in mirror sections. The tubular CD68-positive cells were also positive for nitrotyrosine, gp91 (phox) and Rac 1. They contained lipid in their cytoplasm. Crude BSA, containing free fatty acid, induced CD68 expression in a dose- and time-dependent manner in mProx, but not pure BSA. The surface expression of CD68 was increased by high dose and long term stimulation with crude BSA as shown by immunofluorescence. CONCLUSIONS: We confirmed that tubular epithelial cells have the capacity to transdifferentiate to CD68-positive macrophage-like cells, which may be linked to oxidative stress.

Acute renal failure in a patient with severe malaria and dengue shock syndrome.

Malaria is an infectious disease caused by plasmodium, which lives and breeds in human blood cells, and is transmitted through the bites of Anopheles mosquitoes. Renal impairment, often caused by malaria, is acute renal failure (ARF) due to acute tubular necrosis (ATN). Dengue virus is transmitted from human to human through Aedes aegypti mosquito bites. Dengue hemorrhagic fever (DHF), the most severe stage of infection, is characterized by bleeding and shock tendencies (dengue shock syndrome, DSS). ARF is a less common complication in patients with DHF, with an incidence of less than 10%. Mixed infections of two infectious agents may cause overlapping symptoms and have been reported in Africa and India. We report here a patient with ARF due to mixed infection of severe malaria and DSS. The patient presented with fever and had a history of repeated malaria infection. Physical examination revealed stable vital signs and hepatosplenomegaly. Laboratory data showed hemoconcentration, thrombocytopenia and increased serum aminotransferase. Chest X-ray showed pleural effusion. A malarial antigen and thick smear examination showed the trophozoite stage of P. falciparum. On Day 3, blood pressure dropped to 80/60 mmHg, pulse was 120 beats/minute, weak, and body temperature 36.8 C, with icterus. Other tests revealed an increase of serum urea nitrogen and creatinine levels, and serologically anti-dengue IgG antibody (+) and anti-dengue IgM antibody (-). Based on these findings, we diagnosed the patient as having both malaria and DDS. We treated the patient with the parenteral anti-malarial agent, artemisinin. Supportive treatment and treatment of complications were also performed simultaneously for DSS. The patient experienced an oliguria episode but responded well to a diuretic. The patient was discharged after clinical and laboratory examinations showed positive progress.

Association of endothelial nitric oxide synthase Glu298Asp polymorphism with end-stage renal disease.

BACKGROUND: Impairment of nitric oxide generation caused by gene polymorphism is considered as a major factor in the deterioration of progressive renal disease, including diabetic nephropathy and hypertension. The aim of the present study was to examine the Glu298Asp polymorphism of endothelial nitric oxide synthase (eNOS) in patients with end-stage renal disease (ESRD). METHODS: The Glu298Asp polymorphism in exon 7 was determined in 100 ESRD patients who were maintained on hemodialysis at Dr. Soetomo Hospital, Surabaya, Indonesia, and in a control group of 100 unrelated healthy individuals. In the patient group, 39 patients had Type 2 diabetes mellitus (DM), 44 hypertension (HT) and 17 miscellaneous conditions. The mean length of time from onset of ESRD to the start of this study was 24.37 +/- 32.37 months (Mean +/- SD). RESULTS: The positivity of Glu298Asp in the ESRD group was significantly higher than that in the control group (p < 0.0001). The odds ratio for this group was 4.57 (95% confidence interval 2.52 - 8.31). The positivity of 298Asp in Type 2 DM ESRD with subgroup was significantly higher than that in healthy controls (p < 0.0001). The positivity of 298Asp in the subgroup of patients with HT-derived ESRD was also significantly higher (males p < 0.036, females p < 0.005) than that in healthy control group. Homozygotes with glutamate to aspartate substitution at nucleotide position 7702 showed a single band at 457 bp. CONCLUSION: It appears that Glu298Asp may be a predisposing factor in DM-derived and HT-derived ESRD.

IgA nephropathy: lessons from an animal model, the ddY mouse.

IgA nephropathy is the most common primary chronic glomerulonephritis, and was first described by J. Berger (Transplant Proc. 1969;1:939-944). Histopathologically, IgA nephropathy is characterized by expansion of glomerular mesangial matrix, with mesangial cell proliferation. Glomeruli typically contain generalized-diffuse granular mesangial deposits of IgA, IgG and C3. Since pathogenesis of IgA nephropathy is still obscure, it is important to try to determine the initiation and progression of this disease using a suitable animal model. Several investigators, including Rifai's group (Rhode Island, USA) and Emancipator's group (Cleveland, Ohio, USA), reported various experimental animal models for this disease. In 1985, Imai et al first reported that the ddY strain of mouse can serve as a spontaneous animal model for IgA nephropathy. These mice show mild proteinuria without hematuria, and mesangioproliferative glomerulonephritis with severe glomerular IgA deposits in association with an increase of serum IgA level (Imai et al. Kidney Int. 1985;27:756-761). Electron-dense deposits are observed in the glomerular mesangial areas by electron microscopy. Furthermore, Muso's group succeeded in generating a mouse model of IgA nephropathy with a high incidence and early onset of glomerular IgA deposition (Miyawaki et al. Nephron. 1997;76:201-207). The selection procedure was successful in increasing the serum IgA level of the selected line. The selected ddY line (HIGA mice) showed only mild proteinuria (100-300 mg/dL) and did not show hematuria. These immunohistopathological findings in ddY mice resemble those in IgA nephropathy patients. The objectives of this review are to introduce the genetic background, Th1/Th2 polarization, expansion of extracellular matrices (ECMs) and treatment of IgA nephropathy of the ddY mouse. These findings from the ddY mouse appear to be useful in determining the pathogenesis and treatment of patients with IgA nephropathy.

T cell cytokine polarity as a determinant of immunoglobulin A (IgA) glycosylation and the severity of experimental IgA nephropathy.

Immunoglobulin A (IgA) glycosylation, recognized as an important pathogenic factor in IgA nephropathy (IgAN), is apparently controlled by the polarity of T helper (Th) cytokine responses. To examine the role of cytokine polarity in IgAN, inbred mice were immunized by intraperitoneal priming with inactivated Sendai virus (SeV) emulsified in either complete Freund's adjuvant (CFA) or incomplete Freund's adjuvant (IFA), which promote Th1- or Th2-immune response, respectively, and then boosted identically twice orally with aqueous suspensions of inactivated virus. Next, some mice were challenged intranasally with infectious SeV. Mice primed with CFA or IFA had equal reductions in nasal viral titre relative to non-immune controls, and equally increased serum levels of SeV-specific IgA antibody. Mice primed with CFA showed higher SeV-specific IgG than those with IFA. Splenocytes from mice primed with IFA produced copious amounts of interleukin (IL)-4 and IL-5, but little interferon-gamma and IL-2; those primed with CFA had reciprocal cytokine recall responses. Total serum IgA and especially SeV-specific IgA from mice primed with IFA showed a selective defect in sialylation and galactosylation. Although the frequency and intensity of glomerular deposits and haematuria did not differ, glomerulonephritis in mice primed with IFA and challenged with infectious virus was more severe than in those given CFA, as judged by serum creatinine level. We conclude that the polarity of T cell cytokines controls the pattern of IgA glycosylation and exerts direct or indirect effects on functional glomerular responses to immune complex deposition.

Improvement of peritoneal calcification after parathyroidectomy in a peritoneal dialysis patient.

Peritoneal calcification is one of the complications of peritoneal dialysis (PD). It can become serious, leading to severe abdominal pain and even death. Possible mediators of peritoneal calcification in PD patients are assumed to include acetate buffer, overdosage of vitamin D, repeated peritonitis, hypertonic dialysate, calciphylaxis and secondary hyperparathyroidism (SHPT). However, the mechanism and treatment of peritoneal calcification are controversial. Few reports have appeared on improvement of peritoneal calcification after parathyroidectomy (PTX) for SHPT of long duration. We report herein the case of a 48-year-old man on dialysis for 17 years including PD for 14 years. In 1989, he was admitted to hospital because of end-stage renal disease (ESRD), and started treatment with PD. Abdominal computed tomography (CT) first showed peritoneal calcification in August 2002. Peritoneal calcification did not improve despite conventional treatment including discontinuation of PD, control of calcium phosphate product to less than 55 mg2/dl2, removal of the peritoneal catheter and empirical prednisolone (PSL) usage. The intact parathyroid hormone (i-PTH) level was increased over 1,000 pg/ml and extra-osseous calcification occurred. Total PTX was performed in November 2004. Postoperatively, the i-PTH level decreased immediately and calcium phosphate product was maintained in the reference range. Abdominal CT after PTX showed improvement of peritoneal calcification in September 2005. It appeared that PTX could be used to treat patients with persistent peritoneal calcification not responding to conventional treatment. It was postulated that SHPT might play a crucial role in accelerating peritoneal calcification in PD patients.

Intravenous N-acetylcysteine during hemodialysis reduces asymmetric dimethylarginine level in end-stage renal disease patients.

AIM: Cardiovascular disease is the main cause of mortality in chronic kidney disease patients. Moreover, uremic patients are in a pro-oxidant state and show an increase in asymmetric dimethylarginine (ADMA) levels due to inhibition of the enzyme dimethylarginine dimethylaminohydrolase (DDAH). Asymmetric dimethylarginine per se seems responsible for a 52% increase in the risk of death and for a 34% increase in the risk of cardiovascular events in dialysis patients. N-acetylcysteine (NAC) is a thiol molecule that has direct and indirect antioxidant effects which decrease reactive oxidant species and increase the bioavailability of the DDAH enzyme. The aim of the current study was to determine the effect of intravenous NAC on plasma ADMA level when administered during hemodialysis in end-stage renal disease (ESRD) patients. MATERIALS AND METHODS: 40 patients with ESRD were randomized to receive a 4-hour intravenous infusion of NAC or placebo during a 4-hour hemodialysis session. There were 3 diabetic patients (15%) in the treatment group and 6 patients in the control group. Plasma ADMA levels were measured before and immediately after hemodialysis. Hemodynamic parameters, including pulse pressure, were also measured. The paired t-test was used to compare the difference of ADMA levels before and after hemodialysis in each group, while the independent t-test was used to compare the difference of ADMA levels between the groups. RESULTS: Compared with the pre-dialysis condition, there was a decrease of ADMA level in the control group (1.1253 +/- 0.1797 microM to 0.8676 +/- 0.1449 microM) (p < 0.001), and in the NAC group (1.1522 +/- 0.1737 microM to 0.7844 +/- 0.1586 microM) (p < 0.001). Compared with hemodialysis alone, NAC had a greater lowering effect on the ADMA level (21.3 vs. 31.9%, p < 0.05). CONCLUSION: N-acetylcysteine (NAC) administered intravenously during hemodialysis reduced asymmetric dimethylarginine (ADMA) levels more significantly than hemodialysis alone.

Possible involvement of mast cells in renal fibrosis in patients with IgA nephropathy.

OBJECTIVE: The objective of the present study is to investigate whether human mast cells (MC) contribute to renal damage through local activation of the renin-angiotensin system, by assessing their numbers in renal biopsy specimens from patients with IgA nephropathy (IgAN) or minimal change nephrotic syndrome (MCNS). METHODS: In patients with IgAN and MCNS, the numbers of tryptase-positive MC (MC(T)) and MC positive for both tryptase and chymase (MC(TC)) were examined histopathologically. Serum creatinine level, mean blood pressure and the severity of glomerular and tubulointerstitial lesions were also determined. RESULTS: MC(TC) numbers differed between IgAN patients and MCNS patients. IgAN patients had more MC(TC) than MC(T). MC were found around but not in the conglomerate of the AngiotensinII (AngII)-positive cells. In the IgAN patients with the most severe pathology, the number of AngII-positive cells was correlated with that of MC(TC) and MC(T). CONCLUSION: Chymase-dependent AngII synthesis due to human MC may be involved in the inflammatory and fibrotic processes of IgAN.

Leukocytapheresis (LCAP) for the treatment of rheumatoid arthritis on a maintenance hemodialysis patient.

A 57-year-old-woman, who was treated with regular maintenance hemodialysis (HD), newly contracted rheumatoid arthritis (RA). Oral predonisolone was effective for alleviating her arthralgia but the RA activity became steroid-dependent. For treatment of poorly controlled synovitis leukocytapheresis (LCAP) showed excellent efficacy in the treatment of her joint pain. No serious adverse effects were observed. Serological markers such as CRP, serum amyloid A, matrix metalloproteinase 3 and peripheral blood lymphocyte count fluctuated with her clinical symptoms. We recommend LCAP as candidate therapy for steroid-dependent patients with RA who are on maintenance HD.