A 10-year retrospective cohort study on the risk factors for peritoneal dialysis-related peritonitis: a single-center study at Tokai University Hospital.

BACKGROUND: Common outcomes of peritoneal dialysis (PD)-related peritonitis include catheter removal and transition to hemodialysis (HD). According to recent data, the incidence of PD-related peritonitis in Japan is not low, and peritonitis is the most common cause of withdrawal from PD. Against this backdrop, the purpose of this study is to determine the incidence of PD-related peritonitis at the Outpatient Nephrology Clinic of Tokai University Hospital (hereafter "the Clinic") and to examine causative bacteria and the risk factors related to the development of peritonitis. METHODS: We investigated all PD-related peritonitis episodes of 192 PD patients who visited the Clinic during the period from April 1, 2001 to March 31, 2011 and established the incidence of PD-related peritonitis, along with culture-negative peritonitis rates. Regarding the risk factors that are associated with the development of peritonitis, we examined patient backgrounds, whether an automated peritoneal dialysis (APD) device was used, and which type of connection system was employed. RESULTS: The incidence of peritonitis was one episode per 64.5 patient-months, and the culture-negative peritonitis rate was 16.4 %. Of the cultured bacterial isolates 71.3 % were Gram-positive cocci, including 25.0 % of coagulase-negative staphylococci, 13.2 % of methicillin-susceptible Staphylococcus aureus (MSSA), and 6.6 % of methicillin-resistant Staphylococcus aureus (MRSA). Gram-negative rods were 19.1 %. Risk factors associated with the development of peritonitis included age at the start of PD [odds ratio 1.042, 95 % confidence interval (CI) 1.016-1.069, p value = 0.001], diabetes mellitus nephropathy (DMN) (odds ratio 22.003, 95 % CI 2.101-230.452, p value = 0.010), and the use of a sterile tubing welder device (STWD) (odds ratio 2.399, 95 % CI 1.043-5.521, p value = 0.040). CONCLUSIONS: Regarding the situation of peritonitis at a single center during the 10-year period of this study, risk factors associated with the development of peritonitis included age at the start of PD, DMN, and the use of an STWD.

The onset of antineutrophil cytoplasmic antibody-associated vasculitis immediately after methimazole was switched to propylthiouracil in a woman with Graves' disease who wished to become pregnant.

Propylthiouracil (PTU) is recommended as a first-line antithyroid drug (ATD) during first trimester organogenesis in pregnancy because recent evidence suggests that methimazole (MMI) may be associated with congenital anomalies. However, PTU more commonly causes myeloperoxidase (MPO)-antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis, which usually occurs during prolonged treatment, compared with MMI. We report a case of MPO-ANCA-associated vasculitis in a 35-year-old woman with Graves'disease. Although her thyroid function could be maintained euthyroid by MMI, her ATD was switched to PTU because she wished to become pregnant. The patient presented with flu-like symptoms 8 days after starting PTU and developed hemoptysis and dyspnea at 22 days. Her MPO-ANCA titer was 21 ELISA units (EUs) before PTU treatment but increased to 259 EUs at 22 days after PTU treatment. Her clinical condition improved with the discontinuation of PTU and with immunosuppressive therapy. This case indicated that MPO-ANCA vasculitis occurred within several weeks after the initiation of PTU and that this side effect could be caused by the change from MMI to PTU. Thus, our clinical observation suggests that patients treated with PTU should be carefully monitored for MPO-ANCA titers and variable manifestations of MPO-ANCA-associated vasculitis regardless of the period of administration.

Pasteurella multocida peritonitis associated with a cat in a peritoneal dialysis patient using an automated cycler device.

Pasteurella multocida (P. multocida) is an aerobic Gram-negative coccobacillus, which is found as part of the natural oral flora of many animals, including most healthy cats and dogs. However, it can cause a variety of infections in humans, usually as a result of the patient being bitten or scratched by a cat or dog. There have been 22 reported cases of P. multocida peritonitis in patients undergoing peritoneal dialysis (PD). Of these, 66.7 % occurred within 12 months of the initiation of PD. Only two cases (11.1 %) developed more than 60 months after the commencement of PD. We report a case of P. multocida peritonitis involving a 45-year-old patient who had been undergoing continuous ambulatory peritoneal dialysis (CAPD) for 84 months without a previous history of peritonitis, who developed P. multocida peritonitis associated with a domestic cat on the very night on which he began using an automated cycler device to switch from CAPD to continuous cyclic peritoneal dialysis (CCPD). Patients maintained on PD who keep pets such as cats or dogs at home should be educated about the risk of developing peritonitis related to their domestic pets, and this warning should be repeated when such patients switch from CAPD to CCPD. Physicians should consider using empiric therapy to prevent P. multocida in pet-owning PD patients who present with a history of PD fluid leakage and peritonitis, especially in patients who use cycler devices.

Case of peritoneal dialysis-related acute hydrothorax, which was successfully treated by thoracoscopic surgery, using collagen fleece.

Peritoneal dialysis (PD) is an established renal replacement therapy for patients with end-stage renal disease (ESRD), and it is an effective mean of treatment for maintaining patients' residual renal function and their quality of life (QOL). However, acute hydrothorax is one of the complications of PD that can lead to discontinuation of PD and a switch to hemodialysis. We report a case of a 51-year-old woman with ESRD secondary to chronic glomerulonephritis who was placed on intermittent PD (IPD) and developed right-sided acute hydrothorax one month later. Scintigraphy with technetium-99 m macroaggregated human albumin (Tc-99 m MAA) revealed presence of a pleuroperitoneal communication, and treatment by autologous blood pleurodesis was performed twice. However, the treatment was ineffective, and two months after the onset of the hydrothorax, we performed video-assisted thoracoscopic surgery (VATS), using collagen fleece coated with fibrin glue to seal off the communication. The surgical procedure was followed by complete resolution of the hydrothorax. It was possible to resume the PD about one month postoperatively, and there has been no evidence ofrecurrence of the hydrothorax. VATS with collagen fleece was effective in treating acute hydrothorax secondary to a pleuroperitoneal communication that developed as a complication of PD.

Syndrome of inappropriate antidiuretic hormone secretion in patients with adult Still's disease.

Syndrome of inappropriate antidiuretic hormone secretion (SIADH) is a rare complication of adult Still's disease (ASD). We experienced a male ASD patient who complained of arthralgia and intermittent fever. Chest radiograph and pleural fluid analysis revealed pleurisy with effusion. We diagnosed this patient with SIADH and confirmed the disappearance of hyponatremia and pleurisy after starting treatment with nonsteroidal anti-inflammatory drugs. In this study, we reviewed previous literature and the case of our ASD patient with hyponatremia. This reported case is the fourth case of SIADH in an ASD patient. Further, we found that hyponatremia is a relatively common complication of ASD, and pleurisy has a possibility to develop SIADH in patients with ASD.

Vertebral osteomyelitis associated with Granulicatella adiacens.

Granulicatella adiacens is a nutritionally variant streptococci. Only 3 cases of vertebral osteomyelitis due to these microorganisms have been reported. We experienced a 73-year-old male who consulted us due to fever and back pain of about 1-month duration. On examination, a presystolic murmur was heard in the apical region. Echocardiography showed prolapse of the mitral valve, but no vegetation was observed. MRI revealed osteomyelitis of lumbar vertebrae. As G. adiacens was detected in blood culture, it was determined as the cause of vertebral osteomyelitis, and combination antibiotics therapy was started. The condition improved, the patient underwent valvoplasty, and no trace of infective endocarditis was noted in the resected valve. All the previous cases had infection caused by G. adiacens and complicated with infective endocarditis. This is the first case without infective endocarditis. Vertebral osteomyelitis due to NVS is very rare. Since nutritionally variant streptococci do not grow in common culture media, and since the sensitivity of isolation by standard conventional biochemical methods is low, the condition may be misdiagnosed as blood-culture-negative vertebral osteomyelitis. Therefore, the possibility of nutritionally variant streptococci infection should be considered if a patient with vertebral osteomyelitis shows a positive Gram stain but negative blood cultures.

Comparison of a monoclonal with a polyclonal antibody-based enzyme immunoassay stool test in diagnosing Helicobacter pylori infection after eradication therapy.

BACKGROUND: Recently, a novel Helicobacter pylori stool antigen test (Testmate pylori antigen EIA) using monoclonal antibodies against H. pylori catalase has been developed commercially. This study assessed the diagnostic usefulness of the stool antigen test compared with a polyclonal enzyme immunoassay (HpSA test) after H. pylori eradication. METHODS: A total of 150 patients with H. pylori infection were treated by triple therapy with PPI and amoxicillin with either clarithromycin or metronidazole. H. pylori stool antigen was tested 4 and 8 weeks after eradication. The outcome of H. pylori eradication was assessed by urea breath test (UBT) 8 weeks after the end of therapy. Discordant results were followed by endoscopic examination. RESULTS: Of 150 patients enrolled, H. pylori status was negative in 122 cases and positive in 28 cases, assessed by the 13C-UBT. On the other hand, the monoclonal stool antigen test results were negative in 126 cases and positive in 24. The polyclonal stool test results were negative in 126 cases and positive in 22. The overall sensitivity and specificity of the monoclonal stool antigen test were 91.6% (95% CI 85.9-97.3%) and 98.4% (95% CI 97.3-99.5%). The overall sensitivity and specificity of the polyclonal stool antigen test were 87.0% (95% CI 86.9-94.0%) and 97.5% (95% CI 96.1-98.9%). CONCLUSION: The new stool antigen test using monoclonal antibody is useful for the diagnosis of H. pylori eradication 4 weeks after the end of treatment.

A retrospective study on the efficacy of corticosteroid-alone therapy in membranous nephropathy patients.

OBJECTIVE: Membranous nephropathy (MN) is the most common cause of adult-onset nephrotic syndrome and its management is still controversial. The aim of this study was to determine the effectiveness of corticosteroid-alone therapy for controlling proteinuria in MN. METHODS: Twenty-three patients, which had moderate proteinuria (admission 24-hour urinary protein excretion 1.0 to 3.5 g/day) with primary MN were studied retrospectively. RESULTS: Thirteen patients received corticosteroid-alone therapy combined with rest and dietary therapy (steroid group), while the other 10 patients were treated with rest and diet alone (non-steroid group). These two groups did not differ with respect to their laboratory features at the time of admission. After discharge, 5 of 13 patients of the steroid group dropped out . Therefore, only 8 patients could be followed up. As the result, 5 of 8 patients (62.5%) achieved complete remission (CR) and 3 of 8 patients (37.5%) had incomplete remission (ICR), so none of the patients failed to improve. On the other hand, 3 of 10 patients of the non-steroid group dropped out. Then, 7 patients were followed up. None of the 7 patients showed improvement during follow-up and 5 of these 7 patients were started on corticosteroids. Finally, as this result, 4 of 5 patients (80%) could achieve CR by 2 years after hospital discharge. Moreover, in the remaining 2 patients from the non-steroid group, no remission could be achieved even 2 years after discharge. CONCLUSION: These results suggest that long-term corticosteroid-alone therapy is beneficial for controlling proteinuria in patients with MN.

A case with membranous lupus nephritis developing after a twenty-year remission of membranoproliferative glomerulonephritis.

A 30-year-old woman who showed remission of membranoproliferative glomerulonephritis (MPGN) 20 years previously developed membranous lupus nephritis (MLN). She had photosensitivity, facial erythema, proteinuria of 2.59 g/24 hr, anti-nuclear antibody and anti-ds-DNA antibody. To confirm whether a misdiagnosis of MPGN was made 20 years ago, the clinical data at that time were evaluated retrospectively. She had only mild proteinuria and hematuria but no photosensitivity or facial erythema. Anti-nuclear antibody was negative. Renal biopsy showed occasional lobulation and glomerular capillary double contour. The diagnosis of MPGN was definite. This might be a rare case of one person suffering from two types of glomerulonephritis, MPGN and MLN.

[Case of rheumatoid arthritis with various histological lesions of the kidney].

We experienced a case of rheumatoid arthritis with nephrotic syndrome. A renal biopsy specimen from this patient showed various renal histological changes. The patient was a 50-year-old man who was diagnosed as having rheumatoid arthritis in 1987. We performed a renal biopsy because he had persistent proteinuria from March in 2002. The renal biopsy specimen showed amyloid AA and P protein deposition in the glomeruli. Moreover mild mesangial proliferation was recognized. IgA-deposition in the mesangial area, and granular-deposition of IgG along the glomerular capillary wall were also observed. In electron microscopy, electron dense deposits were recognized in the mesangial area and subepithelium of the glomerular basement membrane. From these findings, we diagnosed amyloid nephropathy, IgA nephritis and membranous nephropathy. Renal biopsy of patients with RA is useful not only for precise diagnosis, but also for selection of the appropriate treatment.

[Clinical significance of IgM deposition in the mesangium and mesangial hypercellularity in adult minimal change nephrotic syndrome].

Minimal change nephrotic syndrome(MCNS) typically shows no abnormalities in light microscopy. However, there are some minor light microscopic abnormalities that are considered to be MCNS variants. In pediatric nephrology, some researchers have reported that IgM deposition in the mesangium and mesangial hypercellularity are related to the response to steroid therapy and the long-term course. However, it is not clear whether IgM deposition in the mesangium and mesangial hypercellularity is responsible for the clinical course or the steroid response of patients with adult MCNS. To investigate the clinical importance of IgM deposition in the mesangium and mesangial hypercellularity, clinical records, follow up data, and renal samples of 47 patients with MCNS were reviewed. We also compared the histological data with those of a normal control group (n = 5). In our study, the presence of mesangial IgM deposition did not predict the patient's clinical course or responsiveness to steroid therapy. Increase in the number of nuclei in the glomeruli and PAS-positive area also did not correlate with the clinical course or responsiveness to steroid therapy. The data suggest that mesangial IgM deposits and increased mesangial cellularity in adult MCNS may not predict the clinical course or steroid response. However, we investigated only 47 samples in this study, therefore, further studies are necessary to identify the importance of IgM deposition in the mesangium and mesangial hypercellularity in adult MCNS.

Relationship between gastric mucosal IL-8 levels and histological gastritis in patients with Helicobacter pylori infection.

To determine the role of host immune responses in H. pylori infection, we examined the relationship between gastric mucosal IL-8 levels and histological gastritis in patients with H. pylori infection. Biopsy tissue obtained from 99 patients were homogenizedand mucosal IL-8 levels measured by ELISA. The gastric mucosal IL-8 levels in both the antrum and corpus were higher in patients with H. pylori than in H. pyloi negativepatients. IL-8 levels in the corpus but not the antrum correlated with the severity of the atrophy. The IL-1B polymorphism had no influence on the degree of IL-8 production. These findings indicate that IL-8 production is independent of IL-1B polymorphisms and IL-8 may play an important role in the development of atrophic gastritis.

Neutral-pH peritoneal dialysis solution improves peritoneal function and decreases matrix metalloproteinase-2 (MMP-2) in patients undergoing continuous ambulatory peritoneal dialysis (CAPD).

BACKGROUND: Conventional lactate-buffered peritoneal dialysis (PD) solutions have several bioincompatible characteristics, including acidic pH, lactate buffer, and the presence of glucose degradation products (GDPs), and these characteristics contribute to membrane dysfunction in PD patients. The formation of GDPs can be reduced by separating the glucose component of the solution from the lactate component during sterilization. This study was carried out to evaluate the clinical effect of dual-chambered neutral-pH PD solution in patients on continuous ambulatory peritoneal dialysis (CAPD). METHODS: Thirteen CAPD patients using conventional PD solution were enrolled in this study. The fast peritoneal equilibration test (fast PET) was performed periodically before and after treatment with neutral PD solution. The concentration of matrix metalloproteinase-2 (MMP-2) in dialysate effluent was measured using 4-h dwelling 2.5% glucose dialysis solution. The patients were categorized into two groups, according to the value of the initial dialysate/plasma (D/P) creatinine ratio: i.e., lower transporters (group L, D/PCr < 0.65) and higher transporters (group H, D/PCr >/= 0.65). RESULTS: The mean D/P creatinine ratio measured by fast PET, was significantly decreased (0.72 +/- 0.09 to 0.60 +/- 0.06; P < 0.03) after treatment with neutral PD solution in group H. The mean glucose level in 4-h dwelling dialysate effluent was elevated (824.6 +/- 195.9 mg/dl to 942.6 +/- 147.8 mg/dl; P < 0.022) in all subjects. In group H, a significant decrease of MMP-2 in the dialysate effluent was recognized from 15 months after the beginning of treatment with the neutral PD solution (141.4 +/- 52.5 ng/ml to 91.3 +/- 15.1 ng/ml; P < 0.05), with the lowest value being shown at 21 months (80.0 +/- 31.8 ng/ml; P < 0.03). CONCLUSIONS: Neutral-pH peritoneal dialysis solution decreased the MMP-2 level in dialysate and improved peritoneal function in high-transporter patients with CAPD treatment.

Glomerular expression of connective tissue growth factor mRNA in various renal diseases.

Connective tissue growth factor (CTGF) is a cysteine-rich member of a new family of growth regulators. It is an important factor in the pathogenesis of mesangial matrix accumulation and progressive glomerulosclerosis. The present study was designed to elucidate the role of CTGF in diabetic nephropathy (DN), immunoglobulin A nephropathy (IgA-N), membranous nephropathy (MN), and minimal change nephrotic syndrome (MCNS). We evaluated the expression and localization of CTGF mRNA in surgically excised renal tissue samples from 10 patients with DN, 10 with IgA-N, 10 with MN, 10 with MCNS, and 10 normal human kidney (NHK) tissue samples, by using high-resolution in situ hybridization with digoxigenin-labelled oligonucleotide. To quantify CTGF mRNA expression, we counted all nuclei, and nuclei surrounded by CTGF-positive cytoplasm, in at least 10 randomly selected cross-sections of non-sclerotic glomeruli, and expressed the results as a percentage of total glomerular cells. In all glomeruli, CTGF mRNA was expressed mainly in glomerular intrinsic cells, including glomerular mesangial and epithelial cells and some cells of Bowman's capsule. The percentage of cells positive for CTGF mRNA was significantly higher in DN and IgA-N than in MN, MCNS and NHK. However, there was no significant difference in the percentage of CTGF mRNA-positive cells between DN and IgA-N. Our study indicates that CTGF may play an important role in the development and progression of glomerulosclerosis in DN and IgA-N, which are both accompanied by mesangial matrix expansion and comprise two major causes of end-stage renal failure.

Affinity adsorption of glucose degradation products improves the biocompatibility of conventional peritoneal dialysis fluid.

BACKGROUND: Reactive carbonyl compounds (RCOs) present in peritoneal dialysis (PD) fluid have been incriminated in the progressive deterioration of the peritoneal membrane in long-term PD patients. They are initially present in fresh conventional heat-sterilized glucose PD fluid and are supplemented during dwell time by the diffusion of blood RCOs within the peritoneal cavity. In the present study, RCO entrapping agents were immobilized on affinity beads to adsorb RCOs both in fresh PD fluid and in PD effluent. METHODS: The RCO trapping potential of various compounds was assessed in vitro first by dissolving them in the tested fluid and subsequently after coupling with either epoxy- or amino-beads. The tested fluids include fresh heat-sterilized glucose and non-glucose PD fluids, and PD effluent. Their RCOs contents, that is, glyoxal (GO), methylglyoxal (MGO), 3-deoxyglucosone (3-DG), formaldehyde, 5-hydroxymethylfuraldehyde, acetaldehyde, and 2-furaldehyde were monitored by reverse-phase high-pressure liquid chromatography. The biocompatibility of PD fluid was assessed by a cytotoxic assay with either human epidermoid cell line A431 cells or with primary cultured human peritoneal mesothelial cells. RESULTS: Among the tested RCO entrapping agents, hydrazine coupled to epoxy-beads proved the most efficient. It lowered the concentrations of three dicarbonyl compounds (GO, MGO, and 3-DG) and those of aldehydes present in fresh heat-sterilized glucose PD fluid toward the low levels observed in filter-sterilized glucose PD fluid. It did not change the glucose and electrolytes concentration of the PD fluid but raised its pH from 5.2 to 5.9. Hydrazine-coupled epoxy-bead also lowered the PD effluent content of total RCOs, measured by the 2,4-dinitrophenylhydrazone (DNPH) method. The cytotoxicity of heat-sterilized PD fluid incubated with hydrazine-coupled epoxy-beads was decreased to the level observed in filter-sterilized PD fluid as the result of the raised pH and the lowered RCOs levels. CONCLUSION: Hydrazine-coupled epoxy-beads reduce the levels of a variety of dicarbonyls and aldehydes present in heat-sterilized glucose PD fluid to those in filter-sterilized PD fluid, without altering glucose, lactate, and electrolytes contents but with a rise in pH. Incubated with PD effluents, it is equally effective in reducing the levels of serum-derived RCOs. RCO entrapping agents immobilized on affinity beads improve in vitro the biocompatibility of conventional heat-sterilized glucose PD fluid. Their clinical applicability requires further studies.