Pathophysiological Mechanisms of Peritoneal Fibrosis and Peritoneal Membrane Dysfunction in Peritoneal Dialysis.

The characteristic feature of chronic peritoneal damage in peritoneal dialysis (PD) is a decline in ultrafiltration capacity associated with pathological fibrosis and angiogenesis. The pathogenesis of peritoneal fibrosis is attributed to bioincompatible factors of PD fluid and peritonitis. Uremia is associated with peritoneal membrane inflammation that affects fibrosis, neoangiogenesis, and baseline peritoneal membrane function. Net ultrafiltration volume is affected by capillary surface area, vasculopathy, peritoneal fibrosis, and lymphangiogenesis. Many inflammatory cytokines induce fibrogenic growth factors, with crosstalk between macrophages and fibroblasts. Transforming growth factor (TGF)-ß and vascular endothelial growth factor (VEGF)-A are the key mediators of fibrosis and angiogenesis, respectively. Bioincompatible factors of PD fluid upregulate TGF-ß expression by mesothelial cells that contributes to the development of fibrosis. Angiogenesis and lymphangiogenesis can progress during fibrosis via TGF-ß-VEGF-A/C pathways. Complement activation occurs in fungal peritonitis and progresses insidiously during PD. Analyses of the human peritoneal membrane have clarified the mechanisms by which encapsulating peritoneal sclerosis develops. Different effects of dialysates on the peritoneal membrane were also recognized, particularly in terms of vascular damage. Understanding the pathophysiologies of the peritoneal membrane will lead to preservation of peritoneal membrane function and improvements in technical survival, mortality, and quality of life for PD patients.

Clinical Impact of Malnutrition According to the Global Leadership Initiative on Malnutrition Criteria Combined With Kidney Dysfunction to Determine Mortality in Inpatients.

OBJECTIVE: The clinical impact of malnutrition based on the Global Leadership Initiative on Malnutrition (GLIM) criteria in patients with kidney dysfunction remains poorly understood. This study investigated the usefulness of GLIM criteria for malnutrition in predicting mortality in patients with kidney dysfunction and different clinical renal states, including no kidney disease (NKD), acute kidney injury (AKI), and chronic kidney disease (CKD). METHODS: This single-center retrospective cohort study included 6,712 patients aged ≥18 admitted between 2018 and 2019. The relationship between the estimated glomerular filtration rate (eGFR) groups, nutritional status based on the GLIM criteria, and the incidence of all-cause mortality was evaluated using a multivariate Cox proportional hazards model. Malnutrition was defined as at least one phenotype (weight loss, low body mass index, or reduced muscle mass) and one etiological criterion (reduced intake/assimilation or disease burden/inflammation). RESULTS: Multivariate Cox proportional hazards model showed that eGFR ≤29 (vs. eGFR: 60-89, adjusted hazard ratio [HR] = 1.84, 95% confidence interval [CI]: 1.52-2.22), 30-59 (vs. eGFR: 60-89, adjusted HR = 1.40, 95% CI: 1.20-1.64), and ≥90 (vs. eGFR: 60-89, adjusted HR = 1.40, 95% CI: 1.14-1.71), moderate and severe malnutrition (vs. without malnutrition, adjusted HR = 1.38 [1.18-1.62] and 2.18 [1.86-2.54], respectively) were independently associated with the incidence of death. The all-cause mortality rate was higher in patients with malnutrition or eGFR ≤29 (adjusted HR, 3.31; 95% CI: 2.51-4.35) than in patients without malnutrition or eGFR 60-89. Furthermore, moderate and severe malnutrition (vs. no malnutrition) was independently associated with death in patients with NKD, AKI, and CKD. CONCLUSION: Malnutrition based on the GLIM criteria was associated with increased all-cause mortality in inpatients, and malnutrition combined with kidney dysfunction was associated with a higher risk of mortality. Furthermore, patients with NKD, AKI, and CKD showed an association between malnutrition based on GLIM criteria and mortality.

Granulocyte-colony stimulating factor producing cervical cancer with elevated levels of parathyroid hormone-related protein: a case report and literature review.

Systemic effects associated with hormones and cytokines secreted by tumor cells can cause paraneoplastic syndrome. Leukemoid reactions and hypercalcemia are relatively common manifestations of paraneoplastic syndrome. Here, we describe the case of a 90-year-old woman who presented with leukocytosis and hypercalcemia and was diagnosed with granulocyte-colony stimulating factor (G-CSF)-producing cervical cancer with elevated levels of parathyroid hormone-related protein (PTHrP). The patient visited our hospital complaining of general fatigue and anorexia. On admission, she presented with marked leukocytosis, hypercalcemia, and an increase in C-reactive protein level. On the basis of abdominal magnetic resonance imaging and histopathological examination, the patient was diagnosed with cervical cancer. Additional tests confirmed elevated plasma levels of G-CSF, PTHrP, and serum interleukin-6. Immunostaining of pathological specimens of the uterine cervix showed expression of G-CSF in tumor cells. The patient was diagnosed with G-CSF-producing cervical cancer accompanied by elevation of PTHrP levels. As a treatment for hypercalcemia, discontinuation of oral vitamin D derivative and administration of saline and elcatonin were ineffective, and therapeutic intervention with zoledronic acid hydrate was required. Considering the patient's advanced age, surgical resection of cervical cancer was not performed. She died from congestive heart failure approximately 3 months after hospitalization. This case was indicated to be a paraneoplastic syndrome in which G-CSF and PTHrP-induced leukocytosis and hypercalcemia. To the best of our knowledge, there have been no reports of G-CSF-producing cervical cancer with elevated PTHrP levels, and our case is the first report.

Association between reduced left ventricular ejection fraction and peritoneal dialysis related peritonitis: a single center retrospective cohort study in Japan.

We present a single-center retrospective analysis of 228 Japanese patients with peritoneal dialysis, in which we examined whether reduced left ventricular ejection fraction (LVEF) is a risk factor for peritonitis development. Time-dependent multivariable-adjusted Cox proportional hazards models revealed that reduced LVEF (LVEF < 50% vs. preserved LVEF ≥ 50%, hazard ratio (HR) 2.10; 95% confidence interval (CI) 1.16-3.82) was associated with peritonitis. Qualitatively, similar associations with reduced LVEF (< 50%) were observed for enteric peritonitis (adjusted HR 7.68; 95% CI 2.51-23.5) but not for non-enteric peritonitis (adjusted HR 1.15; 95% CI 0.54-2.44). Reduced LVEF is associated with a significantly higher risk of subsequent peritonitis, particularly enteric peritonitis. These results indicate that patients with reduced LVEF may be at risk of enteric peritonitis from bowel sources caused by intestinal involvement due to cardiac dysfunction.

Lymphopenia is a risk factor for severe infections in older patients with microscopic polyangiitis: a retrospective cohort study in Japan.

Objective: Previous studies have identified the predictors of severe infections in ANCA-associated vasculitis. However, lymphopenia has not been fully evaluated as a predictor of subsequent severe infections in patients with microscopic polyangiitis (MPA). The aim of this study was to assess the association between lymphopenia and severe infections requiring hospitalization after receiving immunosuppressive therapy for MPA. Methods: This single-centre retrospective cohort study included 130 consecutive patients with newly diagnosed MPA from Aichi Medical University Hospital, Japan, who received immunosuppressive therapy between March 2004 and December 2020. The relationship between lymphopenia and subsequent severe infections was assessed using time-dependent multivariate Cox proportional hazard models adjusted for clinically relevant factors. Results: During the follow-up period (median: 38 months; interquartile range: 15-63 months), 56 severe infectious episodes occurred in 51 patients (39.2%). Time-dependent multivariate Cox proportional hazard analyses identified older age [adjusted hazard ratio (HR) = 1.74 per 10 years, 95% CI: 1.13, 2.67], methylprednisolone pulse therapy (adjusted HR = 2.04, 95% CI: 1.03, 4.02), moderate lymphopenia (vs normal, adjusted HR = 7.17, 95% CI: 3.10, 16.6) and severe lymphopenia (vs normal, adjusted HR = 36.1, 95% CI: 11.8, 110.9) as significant predictors of severe infection. Conclusion: Lymphopenia is a predictor of subsequent severe infections in patients with MPA who receive immunosuppressive therapy. These results suggest the importance of sustained infection surveillance, particularly in older patients who develop lymphopenia during strong immunosuppressive therapy.

Malnutrition according to the GLIM criteria with kidney dysfunction is associated with increased mortality in hospitalized patients with cardiovascular disease: A retrospective cohort study.

BACKGROUND & AIMS: Cardiovascular disease (CVD) is a significant cause of mortality and rising healthcare costs, involving numerous chronic and nutritional risk. Although several studies have reported that malnutrition based on the Global Leadership Initiative on Malnutrition (GLIM) criteria is associated with mortality in patients with CVD, they have not evaluated this association in terms of malnutrition severity (moderate or severe). Furthermore, the relationship between malnutrition combined with renal dysfunction, a risk factor for death in CVD patients, and mortality has not been previously evaluated. Thus, we aimed to assess the association between malnutrition severity and mortality, as well as malnutrition status stratified by kidney function and mortality, in patients hospitalized due to CVD events. METHODS: This single-centre, retrospective cohort study included 621 patients with CVD aged ≥18 years admitted to Aichi Medical University between 2019 and 2020. The relationship between nutritional status based on the GLIM criteria (without malnutrition, moderate malnutrition, or severe malnutrition) and the incidence of all-cause mortality was evaluated by multivariable Cox proportional hazards models. RESULTS: Patients with moderate and severe malnutrition were significantly more prone to mortality than those without malnutrition (adjusted hazard ratio [HR] of patients without, with moderate, and with severe malnutrition: 1.00 [reference], 1.94 [1.12-3.35], and 2.63 [1.53-4.50], respectively). Furthermore, we found the highest all-cause mortality rate in patients with malnutrition and a lower estimated glomerular filtration rate (eGFR <30 mL/min/1.73 m2) (adjusted HR, 10.1; confidence interval, 3.90-26.4) than in patients without malnutrition and normal eGFR (eGFR ≥60 mL/min/1.73 m2). CONCLUSIONS: The present study indicated that malnutrition according to the GLIM criteria was associated with increased all-cause mortality in patients with CVD, and malnutrition associated with kidney dysfunction was associated with a higher risk of mortality. These findings provide clinically relevant information to identify high mortality risk in patients with CVD and highlight the need for giving careful attention to malnutrition with kidney dysfunction among patients with CVD.

Mepolizumab administration for eosinophilic granulomatosis with polyangiitis in an elderly patient with an abrupt onset of limb ischaemia and peripheral neuropathy: A case-based literature review.

Eosinophilic granulomatosis with polyangiitis (EGPA) is a type of anti-neutrophil cytoplasmic antibody-associated vasculitis characterised by small- to medium-sized vessel vasculitis and is typically associated with eosinophilic granulomatous inflammation. EGPA can affect any organ system, most commonly the lungs, skin, and the nervous system. However, limb ulcers are rare complications and have only been described in few case reports. Furthermore, no documented cases of EGPA have been treated with mepolizumab. Herein, we report a case of an 86-year-old Japanese woman with anti-neutrophil cytoplasmic antibody-negative EGPA, who had an abrupt onset of upper limb ulcers and bilateral foot drop due to multiple mononeuropathy. Clinicopathological sural nerve biopsy showed eosinophil-associated vascular damage. The patient was administered steroids, intravenous immunoglobulin, vasodilators, and mepolizumab; this resulted in clinical improvement of her finger ulcers and peripheral neuropathy without any adverse effects. In cases of an abrupt onset of limb ischaemia and peripheral neuropathy, physicians should consider the possibility of EGPA as a differential diagnosis. Furthermore, the early administration of mepolizumab might yield better outcomes in terms of improving limb ischaemia and peripheral neuropathy.

A case of 2,8-DHA crystalline nephropathy caused by adenine phosphoribosyltransferase deficiency: diagnosis and treatment.

Adenine phosphoribosyltransferase (APRT) deficiency is a rare autosomal recessive disorder that leads to the accumulation of poorly soluble 2,8-dihydroxyadenine (DHA) in the kidneys, resulting in a variety of renal presentations including nephrolithiasis, acute kidney injury, and chronic kidney disease (CKD) caused by crystal nephropathy. Here, we report a case of a 43-year-old man with 2,8-DHA crystalline nephropathy caused by APRT deficiency strongly suspected by renal biopsy results and definitively diagnosed by a urine gas chromatography-mass spectrometry (GC/MS)-based plasma metabolomic assessment. This case represents the importance of awareness and recognition of the signs and symptoms of this rare condition and its progression to CKD, which can be prevented by the early administration of xanthine oxidoreductase inhibitors.

Time to normalisation of CRP and incidence of relapse in microscopic polyangiitis: A medical records review study in Japan.

OBJECTIVES: Despite the identification of risk factors for relapses in anti-neutrophil cytoplasmic antibody-associated vasculitis, the relationship between changes in C-reactive protein levels after initial treatment and incidence of relapse remains unknown. This study aimed to assess the association between the time taken for normalisation of C-reactive protein levels and the incidence of relapse in Japanese adult patients with microscopic polyangiitis. METHODS: This study included 85 consecutive patients with newly diagnosed microscopic polyangiitis who achieved remission after six months of immunosuppressive treatment at the Aichi Medical University Hospital, between 2009 and 2017. The relationship between the time to normalisation of C-reactive protein after initial immunosuppressive treatment and relapse incidences was evaluated using multivariable Cox proportional hazard models. RESULTS: During the follow-up period, 13 (30.2%), 7 (41.2%), and 16 (64.0%) patients relapsed (P=0.025) within 1-14, 15-28, and ≥29 days of normalisation, respectively. Hazard ratios (95% confidence intervals) of the time to normalisation of C-reactive protein of 1-14, 15-28, and ≥29 days were 1.00 (reference), 2.42 (95%CI: 0.92-6.39), and 3.48 (95%CI: 1.56-7.76), respectively. CONCLUSIONS: A significant association between the time to normalisation of C-reactive protein and relapse incidence in Japanese patients with microscopic polyangiitis was observed.

Association between renal-limited vasculitis and relapse of antineutrophil cytoplasmic antibody-associated vasculitis: A single-center retrospective cohort study in Japan.

BACKGROUND: Several previous studies have evaluated the predictors of relapse in antineutrophil cytoplasmic antibody-associated vasculitis. Nonetheless, the association between renal-limited vasculitis and relapse has not been evaluated. OBJECTIVE: To assess the association between renal-limited vasculitis and the incidence of relapse in Japan among patients with microscopic polyangiitis/renal-limited vasculitis. METHODS: This retrospective cohort study included consecutive patients in remission at 6 months, with renal-limited vasculitis (n = 24, renal-limited vasculitis group) and microscopic polyangiitis with renal and extra-renal involvement (n = 56, non-renal-limited vasculitis group) between 2004 and 2020. RESULTS: During the median follow-up period of 35 (range, 15‒57) months, 28 (35.0%) patients had a relapse. Multivariable Cox proportional hazards models revealed that the lower estimated glomerular filtration rate (per -10 mL/min/1.73 m2; adjusted hazard ratio = 0.87, 95% confidence interval: 0.76-0.99; P =  0.043), renal-limited vasculitis (adjusted hazard ratio =  0.23, 95% confidence interval: 0.08-0.68; P =  0.008), and glucocorticoid combined with intravenous cyclophosphamide or rituximab (adjusted HR = 0.32, 95% CI: 0.11-0.96; P = 0.042) were associated with a decreased risk of relapse. Glucocorticoid dose during the observation period was lower in the renal-limited vasculitis group than in the non-renal-limited vasculitis group. CONCLUSIONS: Renal-limited vasculitis was associated with a lower risk of relapse than non-renal-limited vasculitis. Our data may contribute to the development of optimal management for renal-limited vasculitis, which may assist in minimizing the adverse effects of immunosuppressive therapy.

Association of alcohol consumption with the incidence of proteinuria and chronic kidney disease: a retrospective cohort study in Japan.

BACKGROUND: The difference in the clinical impact of alcohol consumption on kidney function based on sex remains to be elucidated. This study aimed to assess the association between the dose of alcohol consumption and the incidence of proteinuria and chronic kidney disease stratified by sex. METHODS: This retrospective cohort study included 26,788 workers (19,702 men and 7086 women) with normal renal function (estimated glomerular filtration rate ≥ 60 mL/min/1.73 m2) at annual health examinations between January 2010 and March 2015 in Japan. The main exposure was alcohol consumption. The primary outcomes were the incidence of proteinuria (dipstick urinary protein ≥ 1) and incidence of low estimated glomerular filtration rate (eGFR; rate < 60 mL/min per 1.73 m2; decreased from the baseline eGFR by 25%). RESULTS: During a median observational period of 4 years (interquartile range: 2-6), 1993 (10.1%) men and 462 (6.5%) women developed proteinuria, whereas 667 (3.4%) men and 255 (3.6%) women developed low eGFR. After adjustment for clinically relevant factors using a Cox proportional hazards model, alcohol consumption of ≥ 46 g/day in females was significantly associated with the incidence of proteinuria (hazard ratio, 1.57; 95% confidence interval, 1.10-2.26) and low eGFR (hazard ratio, 1.62; 95% confidence interval, 1.04-2.53). However, no significant association between alcohol consumption and primary outcomes was observed in men. CONCLUSIONS: In conclusion, daily higher alcohol consumption was significantly associated with a higher incidence of proteinuria and low eGFR among women. Women might be prone to high alcohol consumption with kidney dysfunction.

Anti-neutrophil cytoplasmic antibody-associated vasculitis complicated by thrombotic microangiopathy with posterior reversible encephalopathy syndrome successfully treated with eculizumab: A case report.

Thrombotic microangiopathy is characterised by endothelial cell injury, intravascular platelet-fibrin thrombi, and vascular damage, leading to acute kidney injury, thrombocytopenia, and microangiopathic haemolytic anaemia. Among the autoimmune diseases related to thrombotic microangiopathy, anti-neutrophil cytoplasmic antibody-associated vasculitis-related thrombotic microangiopathy cases have been rarely reported; therefore, the optimal treatment for associated vasculitis-related thrombotic microangiopathy remains unknown. An 84-year-old woman without significant medical history presented with a 1-month history of general fatigue, fever, and deteriorating bilateral leg numbness and was admitted to our hospital. She had elevated myeloperoxidase anti-neutrophil cytoplasmic antibody levels, polyneuropathy, and rapid progressive glomerulonephritis because of pauci-immune crescentic glomerulonephritis, as revealed by a kidney biopsy. Accordingly, we diagnosed her with microscopic polyangiitis. After administering methylprednisolone pulse therapy, rituximab, and intravenous immunoglobulin, the patient's mental state deteriorated, presenting signs of thrombotic microangiopathy with posterior reversible encephalopathy syndrome. Intermittent haemodialysis and plasma exchange were initiated; however, her condition did not improve, and eculizumab administration was initiated thereafter. The patient's symptoms showed a remarkable response to eculizumab; thrombotic microangiopathy findings, kidney function, and neurological symptoms improved after only two doses of eculizumab, and she achieved sustained remission. The extremely effective course of eculizumab treatment indicated that overt complement activation affected the development of thrombotic microangiopathy. Anti-neutrophil cytoplasmic antibody-associated vasculitis-related thrombotic microangiopathy may be mediated by complement activation, and prompt induction of eculizumab therapy may be a superior strategy to prevent organ damage. Further studies should elucidate the role of complement activation in associated vasculitis-related thrombotic microangiopathy and the efficacy of eculizumab treatment.

Case report: Thrombotic microangiopathy concomitant with macrophage activation syndrome in systemic lupus erythematosus refractory to conventional treatment successfully treated with eculizumab.

Thrombotic microangiopathy (TMA) is a rare but life-threatening complication of systemic lupus erythematosus (SLE). Macrophage activation syndrome (MAS) is also a rare, life-threatening hyperinflammatory condition that is comorbid with SLE. However, the association between TMA and MAS in patients with SLE has rarely been assessed, and the difficulty of diagnosing these conditions remains prevalent. The efficacy of eculizumab has been reported for SLE patients whose conditions are complicated with TMA. However, no study has investigated the therapeutic efficacy of eculizumab for TMA concomitant with SLE-associated MAS. Herein, we report the first case of TMA concomitant with SLE-associated MAS that was initially refractory to conventional immunosuppressive therapy but showed remarkable recovery after eculizumab treatment. Furthermore, we evaluated serum syndecan-1 and hyaluronan levels, which are biomarkers of endothelial damage. We found that these levels decreased after the administration of eculizumab, suggesting that TMA was the main pathology of the patient. This case illustrates that it is important to appropriately assess the possibility of TMA during the course of SLE-associated MAS and consider the use of eculizumab as necessary.

Long-term good outcome of the fibrocavitary form of pulmonary Mycobacterium avium complex disease with concomitant abatacept monotherapy in a patient with rheumatoid arthritis.

A 53-year-old woman diagnosed with rheumatoid arthritis (RA) demonstrated thick-walled large cavities with consolidation in the left upper lobe on chest computed tomography (CT). Mycobacterium avium was isolated from sputum cultures, and she was diagnosed as having the fibrocavitary (FC) form of pulmonary Mycobacterium avium complex (MAC) disease. Clarithromycin-containing, multidrug, anti-MAC chemotherapy was started immediately. After 7 months, the cavitary lesions improved, and sputum cultures showed negative conversion. Thereafter, abatacept monotherapy was started due to high RA disease activity. Clinical remission of RA has been sustained and cavitary lesions disappeared by concomitant abatacept and anti-MAC therapy for more than 5 years. Immediate initiation of anti-MAC therapy and prior confirmed efficacy are needed for the treatment of the FC form. Abatacept and anti-MAC therapy could be continued, leading to the withdrawal of prednisolone, along with careful observation by strict chest CT evaluation and repeated sputum cultures. Biologics are generally contraindicated for pulmonary MAC disease, particularly the FC form. When there is a pre-existing lung lesion apparently of FC type, abatacept cannot be started without prior anti-MAC chemotherapy. This case suggests that abatacept may be carefully used to avoid progressive joint destruction after FC lesions of pulmonary MAC disease are resolved.

Roles of glomerular endothelial hyaluronan in the development of proteinuria.

Vascular endothelial cells are covered with glycocalyx comprising heparan sulfate, hyaluronan, chondroitin sulfate, and associated proteins. Glomerular endothelial glycocalyx is involved in protecting against induction of proteinuria and structural damage, but the specific components in glycocalyx that represent therapeutic targets remain unclear. Anti-vascular endothelial growth factor (VEGF) therapy is associated with an increased risk of glomerular endothelial injury. This study investigated whether hyaluronan could provide a therapeutic target to protect against proteinuria. We conducted ex vivo and in vivo experiments to explore the effects of degrading glomerular hyaluronan by administering hyaluronidase and of supplementation with hyaluronan. We investigated hyaluronan expression using biotin-labeled hyaluronan-binding protein (HABP) in human kidney specimens or serum hyaluronan in endothelial injuries under inhibition of VEGF signaling. We directly demonstrated hyaluronan in glomerular endothelial layers using HABP staining. Ex vivo and in vivo experiments showed the development of proteinuria after digestion of hyaluronan in glomerular capillaries. Supplementation with hyaluronan after hyaluronidase treatment suppressed proteinuria. Mice in the in vivo study developed albuminuria after intraperitoneal injection of hyaluronidase with decreased glomerular hyaluronan and increased serum hyaluronan. In human kidneys with endothelial cell dysfunction and proteinuria due to inhibition of VEGF, glomerular expression of hyaluronan was reduced even in normal-appearing glomeruli. Serum hyaluronan levels were elevated in patients with pre-eclampsia with VEGF signaling inhibition. Our data suggest that hyaluronan itself plays crucial roles in preventing proteinuria and preserving the integrity of endothelial cells. Hyaluronan could provide a therapeutic target for preventing glomerular endothelial glycocalyx damage, including VEGF signaling inhibition.

Association between serum magnesium levels and abdominal aorta calcification in patients with pre-dialysis chronic kidney disease stage 5.

BACKGROUND: Several studies have revealed the relationship between serum magnesium levels and vascular calcification in chronic kidney disease patients. Despite excellent predictability of abdominal aorta calcification for cardiovascular disease events, the relationship between serum magnesium levels and abdominal aorta calcification, as evaluated by quantitative methods, in pre-dialysis patients remains unclear. This study aimed to determine the abdominal aorta calcification volume using computerized tomography and its association with serum magnesium levels in pre-dialysis chronic kidney disease stage 5 patients. METHODS: This single-center cross-sectional study included 100 consecutive patients with pre-dialysis chronic kidney disease stage 5 between January 2016 and May 2020 at Aichi Medical University Hospital, Japan. The relationships between serum magnesium levels and the abdominal aorta calcification volume were assessed using multiple linear regression models after adjusting for clinically relevant factors. We also assessed clinical factors that affect serum magnesium levels. RESULTS: The mean serum magnesium level was 2.0 mg/dL (interquartile range, 1.8 to 2.3). Multivariate analyses revealed that a higher serum magnesium level (stand. ß = -0.245, p = 0.010) was significantly associated with a reduced abdominal aorta calcification volume, and that a history of cardiovascular disease (stand. ß = 0.3792, p < 0.001) and older age (stand. ß = 0.278, p = 0.007) were significantly associated with an increased abdominal aorta calcification volume. Moreover, multivariate analysis showed that the use of proton pump inhibitor or potassium-competitive acid blocker was significantly associated with lower serum magnesium levels (stand. ß = -0.246, p = 0.019). CONCLUSIONS: The present study revealed that the higher Mg level was significantly associated with lower volume of abdominal aorta calcification in pre-dialysis chronic kidney disease stage 5 patients. Further studies should be undertaken to determine the appropriate magnesium level to suppress vascular calcification.

Low-GDP, pH-neutral solutions preserve peritoneal endothelial glycocalyx during long-term peritoneal dialysis.

BACKGROUND: During peritoneal dialysis (PD), solute transport and ultrafiltration are mainly achieved by the peritoneal blood vasculature. Glycocalyx lies on the surface of endothelial cells and plays a role in vascular permeability. Low-glucose degradation product (GDP), pH-neutral PD solutions reportedly offer higher biocompatibility and lead to less peritoneal injury. However, the effects on the vasculature have not been clarified. METHODS: Peritoneal tissues from 11 patients treated with conventional acidic solutions (acidic group) and 11 patients treated with low-GDP, pH-neutral solutions (neutral group) were examined. Control tissues were acquired from 5 healthy donors of kidney transplants (control group). CD31 and ratio of luminal diameter to vessel diameter (L/V ratio) were evaluated to identify endothelial cells and vasculopathy, respectively. Immunostaining for heparan sulfate (HS) domains and Ulex europaeus agglutinin-1 (UEA-1) binding was performed to assess sulfated glycosaminoglycans and the fucose-containing sugar chain of glycocalyx. RESULTS: Compared with the acidic group, the neutral group showed higher CD31 positivity. L/V ratio was significantly higher in the neutral group, suggesting less progression of vasculopathy. Both HS expression and UEA-1 binding were higher in the neutral group, whereas HS expression was markedly more preserved than UEA-1 binding in the acidic group. In vessels with low L/V ratio, which were found only in the acidic group, HS expression and UEA-1 binding were diminished, suggesting a loss of glycocalyx. CONCLUSION: Peritoneal endothelial glycocalyx was more preserved in patients treated with low-GDP, pH-neutral solution. The use of low-GDP, pH-neutral solutions could help to protect peritoneal vascular structures and functions.

Association between body mass index and severe infection in older adults with microscopic polyangiitis: a retrospective cohort in Japan.

BACKGROUND: Although previous studies have evaluated risk factors for the incidence of severe infection in patients with antineutrophil cytoplasmic antibody-associated vasculitis (AAV), the relationship between body mass index (BMI) and severe infection in AAV has not been elucidated. We hypothesized that older adults with AAV and a low BMI would be at a higher risk of infection. We therefore investigated the association between underweight status at AAV diagnosis and subsequent occurrence of severe infection in older adults with AAV. METHODS: This single-center retrospective cohort study included 93 consecutive older adults with microscopic polyangiitis (MPA) treated at the Aichi Medical University Hospital in Japan between 2004 and 2018. The relationships between BMI at diagnosis and subsequent first severe infection were assessed using multivariate Cox proportional hazards models. The cumulative probability of the development of the first severe infection was calculated using the Kaplan-Meier method and the log-rank test. The level of statistical significance was set at P <  0.05. RESULTS: During the median follow-up period of 19 (6-53) months, 29 (31.2%) patients developed at least one severe infection. Older age (adjusted hazard ratio [HR] = 2.02, 95% confidence interval [CI]: 1.14-3.52, per 10 years; P =  0.016), low BMI (< 18.5 kg/m2 compared with normal BMI [18.5-23.0 kg/m2], adjusted HR =  2.63, 95% CI: 1.11-6.19; P =  0.027), and use of methylprednisolone pulse therapy (adjusted HR = 2.48, 95% CI: 1.07-5.76; P =  0.034) were found to be significant predictors of severe infection. CONCLUSIONS: Low BMI was associated with a higher risk of severe infection in older adults with MPA, suggesting that careful management may be required to prevent this complication in this vulnerable group. Further studies are needed to elucidate the optimal treatment strategy for these patients.