Persistent Pruritic Linear Streaks of Adult-Onset Still's Disease: Reconsidering the Yamaguchi Criteria.

Objective Adult-onset Still's disease (AOSD) is a rare orphan disease, the diagnosis of which remains challenging. This study aimed to identify additional clues for establishing early diagnosis beyond the existing criteria. Methods A retrospective longitudinal cohort study was conducted at two community hospitals in Japan between March 2012 and December 2022. The clinical characteristics and medical histories of patients with AOSD were extracted from the clinical records. The primary outcome was to identify the key manifestations of AOSD for an early diagnosis beyond the existing criteria. Results Twenty-one patients (mean age, 58 years) were included in the study. Fever was the first symptom in 13 out of 21 patients (62%). Six out of 21 patients (29%) presented with a pruritic rash only, while two out of 21 (10%) initially presented with a sore throat. All patients visited more than one medical institution. The median time to reach a correct diagnosis was 41 days (IQR 19-138). Nineteen out of 20 patients (95%) exhibited a pruritic rash, identified as persistent pruritic linear streaks, with a median duration of 21 days (IQR 12-64) before the diagnosis of AOSD as a cutaneous manifestation. Conclusions Persistent pruritic linear streaks were a key feature in the context of an early diagnosis of AOSD, offering an option for reconsidering and revising the existing classification criteria.

Effectiveness of intravenous methylprednisolone pulse in patients with severe microscopic polyangiitis and granulomatosis with polyangiitis.

OBJECTIVES: To evaluate the effectiveness and safety of two different intravenous methylprednisolone (IVMP) pulse doses in patients with severe microscopic polyangiitis (MPA) and granulomatosis with polyangiitis (GPA). METHODS: We emulated a target trial using observational data from the nationwide registry in Japan. Patients with severe glomerulonephritis or diffuse alveolar haemorrhage were selected and pseudo-randomised into three groups using propensity score-based overlap weighting as follows: non-IVMP, IVMP 0.5 g/day, and IVMP 1.0 g/day. The primary outcome was all-cause death, and the secondary outcomes were composite all-cause death and kidney failure, severe relapse, and serious infection from 2 to 48 weeks after treatment initiation. To estimate the treatment effects, the Cox proportional hazard model and Fine-Gray subdistribution hazard model were used. RESULTS: In this emulated target trial, of 201 eligible patients (MPA, 175; GPA, 26), 6 (2.8%) died, 4 (2.0%) had kidney failure, 11 (5.3%) had severe relapse, and 40 (19.8%) had severe infections. Hazard ratios (HR) for IVMP 0.5 g/day and IVMP 1.0 g/day pulse groups compared with non-IVMP pulse were as follows: all-cause death = 0.46 (95% confidence interval [95%CI]: 0.07-2.81) and 0.07 (95%CI: 0.01-0.41); all-cause death/kidney failure = 1.18 (95%CI: 0.26-5.31) and 0.59 (95%CI: 0.08-4.52); subdistribution HRs for severe relapse = 1.26 (95%CI: 0.12-13.70) and 3.36 (95%CI: 0.49-23.29); and serious infection = 1.88 (95%CI: 0.76-4.65) and 0.94 (95%CI: 0.28-3.13). CONCLUSIONS: IVMP 1.0 g/day pulse may improve 48-week mortality in patients with severe MPA/GPA.

Optimal Dose of Intravenous Cyclophosphamide during remission induction therapy in ANCA-associated vasculitis: a retrospective cohort study of J-CANVAS.

OBJECTIVES: To identify the optimal dose of intravenous cyclophosphamide (IVCY) for induction therapy for anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV). METHODS: We retrospectively assessed patients with AAV who received IVCY every 2-3 weeks during the remission induction phase. The associations of the IVCY dose with infection-free survival and relapse-free survival were analysed using a Cox regression model. We compared patients in three categories: very low-dose (VLD), low-dose (LD), and conventional dose (CD) (<7.5 mg/kg, 7.5-12.5 mg/kg, and >12.5 mg/kg, respectively). The non-linear association between IVCY dose and the outcomes were also evaluated. RESULTS: Of the 80 patients (median age 72 years), 12, 42, and 26 underwent the VLD, LD, and CD regimens, respectively, of whom 4, 3, and 7 developed infection or died. The adjusted hazard ratios for infection or death were 4.3 (95% confidence interval (CI) 0.94-19.8) for VLD and 5.1 (95% CI 1.21-21.3) for CD, compared with LD. We found the hazard ratio for infection or death increased when the initial IVCY dose exceeded 9 mg/kg. Relapse-free survival did not differ clearly. CONCLUSION: Low-dose IVCY (7.5-12.5 mg/kg) may result in fewer infections and similar relapse rates compared with the conventional regimen (>12.5 mg/kg).

Seasonal Influence on Development of Antineutrophil Cytoplasmic Antibody-Associated Vasculitis: A Retrospective Cohort Study Conducted at Multiple Institutions in Japan (J-CANVAS).

OBJECTIVE: To clarify seasonal and other environmental effects on the onset of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). METHODS: We enrolled patients with new-onset eosinophilic granulomatosis with polyangiitis (EGPA), microscopic polyangiitis (MPA), and granulomatosis with polyangiitis (GPA) registered in the database of a Japanese multicenter cohort study. We investigated the relationship between environmental factors and clinical characteristics. Seasons were divided into 4 (spring, summer, autumn, and winter), and the seasonal differences in AAV onset were analyzed using Pearson chi-square test, with an expected probability of 25% for each season. RESULTS: A total of 454 patients were enrolled, with a mean age of 70.9 years and a female proportion of 55.5%. Overall, 74, 291, and 89 patients were classified as having EGPA, MPA, and GPA, respectively. Positivity for myeloperoxidase (MPO)-ANCA and proteinase 3 (PR3)-ANCA was observed in 355 and 46 patients, respectively. Overall, the seasonality of AAV onset significantly deviated from the expected 25% for each season (P = 0.001), and its onset was less frequently observed in autumn. In ANCA serotypes, seasonality was significant in patients with MPO-ANCA (P < 0.001), but not in those with PR3-ANCA (P = 0.97). Additionally, rural residency of patients with AAV was associated with PR3-ANCA positivity and biopsy-proven pulmonary vasculitis. CONCLUSION: The onset of AAV was influenced by seasonal variations and was less frequently observed in autumn. In contrast, the occurrence of PR3-ANCA was triggered, not by season, but by rural residency.

Association between hypogammaglobulinaemia and severe infections during induction therapy in ANCA-associated vasculitis: from J-CANVAS study.

OBJECTIVES: To investigate the association between decreased serum IgG levels caused by remission-induction immunosuppressive therapy of antineutrophil cytoplasmic antibody-associated vasculitis (AAV) and the development of severe infections. METHODS: We conducted a retrospective cohort study of patients with new-onset or severe relapsing AAV enrolled in the J-CANVAS registry, which was established at 24 referral sites in Japan. The minimum serum IgG levels up to 24 weeks and the incidence of severe infection up to 48 weeks after treatment initiation were evaluated. After multiple imputations for all explanatory variables, we performed the multivariate analysis using a Fine-Gray model to assess the association between low IgG (the minimum IgG levels <500 mg/dl) and severe infections. In addition, the association was expressed as a restricted cubic spline (RCS) and analysed by treatment subgroups. RESULTS: Of 657 included patients (microscopic polyangiitis, 392; granulomatosis with polyangiitis, 139; eosinophilic granulomatosis with polyangiitis, 126), 111 (16.9%) developed severe infections. The minimum serum IgG levels were measured in 510 patients, of whom 77 (15.1%) had low IgG. After multiple imputations, the confounder-adjusted hazard ratio of low IgG for the incidence of severe infections was 1.75 (95% confidence interval: 1.03-3.00). The RCS revealed a U-shaped association between serum IgG levels and the incidence of severe infection with serum IgG 946 mg/dl as the lowest point. Subgroup analysis showed no obvious heterogeneity between treatment regimens. CONCLUSION: Regardless of treatment regimens, low IgG after remission-induction treatment was associated with the development of severe infections up to 48 weeks after treatment initiation.

A case report of two systemic lupus erythematosus pregnancies with early placental exposure to belimumab: Case report with review.

Since its approval for the management of systemic lupus erythematosus (SLE), belimumab has been widely used. However, its pregnancy safety profile has been underinvestigated. We present the pregnancy outcomes of two cases of early placental exposure to belimumab and summarise the pregnancy outcomes in previous reports regarding placental exposure to belimumab. Case 1 describes a 27-year-old woman with an 18-year history of SLE and lupus nephritis class III. We introduced belimumab 19 months prior to conception to control her proteinuria and discontinued its use at 5 weeks and 5 days of gestation. Her lupus activity was stable throughout pregnancy, and at 37 weeks and 1 day of gestation, she delivered a healthy girl with no anomaly. At delivery, the girl was small for gestational age, but at the 1-year follow-up, there was no delay in her growth or any serious infection. Case 2 describes a 32-year-old woman with a 15-year history of SLE. We introduced belimumab 9 months prior to conception and discontinued its use at 7 weeks and 1 day of gestation. Although her lupus was well controlled without belimumab, a missed abortion occurred, which was possibly due to foetal factors. Although there is accumulating data on the safety of belimumab use during pregnancy, it seems necessary to cautiously use this medication in pregnant women, until further analyses are conducted.

Advantages of an alternate-day glucocorticoid treatment strategy for the treatment of IgG4-related disease: A preliminary retrospective cohort study.

Alternate-day glucocorticoid (GC) therapy is a treatment option that can reduce GC-associated adverse events. We investigated the safety and efficacy of alternate-day GC therapy in patients with immunoglobulin G4-related disease (IgG4-RD). Medical records of patients with IgG4-RD who were followed for at least one year at St. Luke's International Hospital, Tokyo, Japan, from 2004 to 2020 were reviewed. Patients who fulfilled comprehensive IgG4-RD diagnostic criteria were divided into alternate-day or daily GC treatment groups based on their treatment protocol. The effect of alternate-day GC therapy on glucocorticoid toxicity index (GTI) score was evaluated using multilinear analysis with adjustments for cumulative GC doses until each assessment point and propensity scores (PS) for alternate-day GC therapy. Kaplan-Meier curves and Cox proportional hazard models were used to assess the efficacy of alternate-day GC therapy for disease control. Among the 67 patients with IgG4-RD, patients with alternate-day (n = 13) and daily (n = 31) GC treatments were analyzed after excluding 23 ineligible patients. The median (interquartile range) age was 64 (60-70) years, 29 (65.9%) were male patients, 26 (59.1%) patients had positive biopsy results, and the median follow-up period was 1643 days. Significantly more patients with alternate-day GC treatment used concomitant immunosuppressants (11 [84.6%] vs 11 [35.5%]; P = .007). The alternate-day strategy significantly lowered the GTI score after adjusting for cumulative GC dose until the assessment and PS (adjusted coefficient: -29.5 [-54.3, -4.8], P = .021 at 12 months; -20.0 [-39.8, -0.1], P = .049 at 24 months). Serious infections were numerically less frequent in the alternate-day group (incidence ratio [95% confidence interval [CI]: 0.45 [0.05, 3.63], P = .45). Most patients (92.3%) in the alternate-day GC treatment group and all patients in the daily GC treatment group showed treatment responses in the remission induction therapy. The PS-adjusted hazard ratio of alternate-day GC treatment for disease flares was not significant (1.55 [0.53, 4.51]; P = .43). The alternate-day treatment strategy significantly reduced GC-related adverse events regardless of the cumulative GC dose. Alternate-day GC treatment is a feasible option for patients with IgG4-RD, without a significant increase in disease flares particularly when combined with immunosuppressants.

Hypertrophic pachymeningitis in ANCA-associated vasculitis: a cross-sectional and multi-institutional study in Japan (J-CANVAS).

BACKGROUND: This study investigated the characteristics of hypertrophic pachymeningitis (HP) in antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV), using information from a multicenter study in Japan. METHODS: We analyzed the clinical information of 663 Asian patients with AAV (total AAV), including 558 patients with newly diagnosed AAV and 105 with relapsed AAV. Clinical findings were compared between patients with and without HP. To elucidate the relevant manifestations for HP development, multivariable logistic regression analyses were additionally performed. RESULTS: Of the patients with AAV (mean age, 70.2 ± 13.5 years), HP was noted in 30 (4.52%), including 20 (3.58%) with newly diagnosed AAV and 10 (9.52%) with relapsed AAV. Granulomatosis with polyangiitis (GPA) was classified in 50% of patients with HP. A higher prevalence of GPA was significantly observed in patients with HP than in those without HP in total AAV and newly diagnosed AAV (p < 0.001). In newly diagnosed AAV, serum proteinase 3 (PR3)-ANCA positivity was significantly higher in patients with HP than in those without HP (p = 0.030). Patients with HP significantly had ear, nose, and throat (ENT) (odds ratio [OR] 1.48, 95% confidence interval [CI] 1.03-2.14, p = 0.033) and mucous membrane/eye manifestations (OR 5.99, 95% CI 2.59-13.86, p < 0.0001) in total AAV. Moreover, they significantly had conductive hearing loss (OR 11.6, 95% CI 4.51-29.57, p < 0.0001) and sudden visual loss (OR 20.9, 95% CI 5.24-85.03, p < 0.0001). CONCLUSION: GPA was predominantly observed in patients with HP. Furthermore, in newly diagnosed AAV, patients with HP showed significantly higher PR3-ANCA positivity than those without HP. The ear and eye manifestations may be implicated in HP development.

Effect and safety profile of belimumab and tacrolimus combination therapy in thirty-three patients with systemic lupus erythematosus.

INTRODUCTION/OBJECTIVES: Belimumab combined with mycophenolate mofetil has been proven to be effective for treating systemic lupus erythematosus (SLE) in several randomized controlled trials. Calcineurin inhibitors are also useful in controlling the activity of SLE. However, the safety and effectiveness of belimumab-calcineurin inhibitor combination therapy have not been addressed. Therefore, the current single-center retrospective study aimed to analyze the safety/efficacy profile of belimumab-tacrolimus (B-T) combination therapy in patients with SLE. METHOD: Patients with SLE administered tacrolimus and belimumab during treatment were included in the study. Samples were analyzed for the drug retention rate, SLE flare rate, infection incidence rate, and glucocorticoid-sparing effect of the B-T combination therapy. RESULTS: Thirty-three patients with SLE were treated with B-T combination therapy at our institution. Four patients discontinued treatment due to insufficient response or adverse events. The drug retention rate was over 90% at week 52 and approximately 80% at day 1000. Only one patient developed serious infection. The lupus low disease activity state (LLDAS) achievement ratio was 9.1% on the day of initiation and improved to 64.0% at 52 weeks after initiation. SLE flares were observed in three patients (9.1%) in the first 52 weeks after initiation, and in five patients (15.2%) throughout the study period. A glucocorticoid-reducing effect was also observed in patients treated with B-T combination therapy. CONCLUSIONS: In most patients with SLE, B-T combination therapy is well tolerated with a good efficacy profile and glucocorticoid-reducing effect. Thus, B-T combination therapy represents a feasible option for patients with refractory lupus. Key Points • The safety and effectiveness of belimumab-calcineurin inhibitor combination therapy have not been addressed. • The drug retention rate of belimumab-tacrolimus combination therapy was over 90% at week 52 and around 80% on day 1000 • Almost none of the patients suffered from severe infection after the initiation of belimumab-tacrolimus combination therapy. • Belimumab-tacrolimus combination therapy is efficacious in suppressing lupus activity and achieving LLDAS.

Different Spatial and Temporal Roles of Monocytes and Monocyte-Derived Cells in the Pathogenesis of an Imiquimod Induced Lupus Model.

Mounting evidence indicates the importance of aberrant Toll-like receptor 7 (TLR7) signaling in the pathogenesis of systemic lupus erythematosus (SLE). However, the mechanism of disease progression remains unclear. An imiquimod (IMQ)-induced lupus model was used to analyze the lupus mechanism related to the aberrant TLR7 signals. C57BL/6 mice and NZB/NZW mice were treated with topical IMQ, and peripheral blood, draining lymph nodes, and kidneys were analyzed focusing on monocytes and monocyte-related cells. Monocytes expressed intermediate to high levels of TLR7, and the long-term application of IMQ increased Ly6Clo monocytes in the peripheral blood and Ly6Clo monocyte-like cells in the lymph nodes and kidneys, whereas Ly6Chi monocyte-like cell numbers were increased in lymph nodes. Ly6Clo monocyte-like cells in the kidneys of IMQ-induced lupus mice were supplied by bone marrow-derived cells as demonstrated using a bone marrow chimera. Ly6Clo monocytes obtained from IMQ-induced lupus mice had upregulated adhesion molecule-related genes, and after adoptive transfer, they showed greater infiltration into the kidneys compared with controls. RNA-seq and post hoc PCR analyses revealed Ly6Clo monocyte-like cells in the kidneys of IMQ-induced lupus mice had upregulated macrophage-related genes compared with peripheral blood Ly6Clo monocytes and downregulated genes compared with kidney macrophages (MF). Ly6Clo monocyte-like cells in the kidneys upregulated Il6 and chemoattracting genes including Ccl5 and Cxcl13. The higher expression of Il6 in Ly6Clo monocyte-like cells compared with MF suggested these cells were more inflammatory than MF. However, MF in IMQ-induced lupus mice were characterized by their high expression of Cxcl13. Genes of proinflammatory cytokines in Ly6Chi and Ly6Clo monocytes were upregulated by stimulation with IMQ but only Ly6Chi monocytes upregulated IFN-α genes upon stimulation with 2'3'-cyclic-GMP-AMP, an agonist of stimulator of interferon genes. Ly6Chi and Ly6Clo monocytes in IMQ-induced lupus mice had different features. Ly6Chi monocytes responded in the lymph nodes of locally stimulated sites and had a higher expression of IFN-α upon stimulation, whereas Ly6Clo monocytes were induced slowly and tended to infiltrate into the kidneys. Infiltrated monocytes in the kidneys likely followed a trajectory through inflammatory monocyte-like cells to MF, which were then involved in the development of nephritis.

Visualization of the strain-induced topological phase transition in a quasi-one-dimensional superconductor TaSe3.

Control of the phase transition from topological to normal insulators can allow for an on/off switching of spin current. While topological phase transitions have been realized by elemental substitution in semiconducting alloys, such an approach requires preparation of materials with various compositions. Thus it is quite far from a feasible device application, which demands a reversible operation. Here we use angle-resolved photoemission spectroscopy and spin- and angle-resolved photoemission spectroscopy to visualize the strain-driven band-structure evolution of the quasi-one-dimensional superconductor TaSe3. We demonstrate that it undergoes reversible strain-induced topological phase transitions from a strong topological insulator phase with spin-polarized, quasi-one-dimensional topological surface states, to topologically trivial semimetal and band insulating phases. The quasi-one-dimensional superconductor TaSe3 provides a suitable platform for engineering the topological spintronics, for example as an on/off switch for a spin current that is robust against impurity scattering.

Effectiveness and safety of mizoribine for the treatment of IgG4-related disease: a retrospective cohort study.

OBJECTIVE: Patients with IgG4-related disease (IgG4RD) usually require steroid-sparing agents due to relapse with tapering glucocorticoids (GC). We aimed to determine the efficacy and safety of mizoribine (MZR) among IgG4RD patients. METHODS: We retrospectively reviewed records of IgG4RD patients at Immuno-Rheumatology Center in St. Luke's International Hospital, Tokyo, Japan. Patients treated with MZR were classified into the MZR group, and those treated with GC alone or with other immunosuppressants were included in the control group. Disease exacerbation, GC dose, IgG-IgG4 titre and adverse events were evaluated using univariate analyses, including the Kaplan-Meier method. The Cox proportional hazard model was used to evaluate risk factors for disease exacerbation. RESULTS: A total of 14 and 29 cases were included in the MZR and control group. Multiple organ involvement (three or more organs) was significantly more frequent in the MZR group [10 (71.4%) vs 9 (31.0%), P= 0.021]. Kaplan-Meier analysis revealed a significant reduction inexacerbation in patients with multiple organ involvement (P< 0.001) but not in total (P= 0.42). The adjusted hazard ratios of MZR use and multiple organ involvement for exacerbation were 0.34 (95%CI 0.12-1.01; P = 0.052) and 3.51 (95%CI 1.29-9.51; P= 0.014). The cumulative GC dose (mg per year, interquartile range) tended to be lower in the MZR group [1448 (1003-1642) vs 2179 (1264-3425); P= 0.09]. CONCLUSION: MZR decreased disease exacerbation among IgG4RD patients with multi-organ involvement and showed a steroid-sparing effect. MZR could be a treatment option for IgG4RD.

A Critical Role for Mucosal-Associated Invariant T Cells as Regulators and Therapeutic Targets in Systemic Lupus Erythematosus.

Mucosal-associated invariant T (MAIT) cells are a subset of innate-like lymphocytes that are restricted by major histocompatibility complex-related molecule 1 (MR1). In this study, we investigated the role of MAIT cells in the pathogenesis of lupus in FcγRIIb-/-Yaa mice, a spontaneous animal model of lupus. Using two approaches of MAIT cell deficiency, MR1 knockout animals and a newly synthesized inhibitory MR1 ligand, we demonstrate that MAIT cells augment the disease course of lupus by enhancing autoantibody production and tissue inflammation. MR1 deficiency reduced germinal center responses and T cell responses in these mice. Suppression of MAIT cell activation by the inhibitory MR1 ligand reduced autoantibody production and lupus nephritis in FcγRIIb-/-Yaa mice. MAIT cells directly enhanced autoantibody production by B cells in vitro. Our results indicate the contribution of MAIT cells to lupus pathology and the potential of these cells as novel therapeutic targets for autoimmune diseases such as lupus.

Petunidin, a B-ring 5'-O-Methylated Derivative of Delphinidin, Stimulates Osteoblastogenesis and Reduces sRANKL-Induced Bone Loss.

Several lines of evidence suggest that oxidative stress is one of the key pathogenic mechanisms of osteoporosis. We aimed to elucidate the bone protective effects of petunidin, one of the most common anthocyanidins, considering its potent antioxidative activity. Petunidin (>5 µg/mL) significantly inhibited osteoclastogenesis and downregulated c-fos, Nfatc1, Mmp9, Ctsk, and Dc-stamp mRNA expression in RAW264.7 cells. Conversely, petunidin (>16 µg/mL) stimulated mineralized matrix formation and gene expression of Bmp2 and Ocn, whereas it suppressed Mmp13, Mmp2, and Mmp9 mRNA expression and proteolytic activities of MMP13 and MMP9 in MC3T3-E1 cells. Micro-CT and bone histomorphometry analyses of sRANKL-induced osteopenic C57BL/6J mice showed that daily oral administration of petunidin (7.5 mg/kg/day) increased bone volume to tissue volume (BV/TV), trabecular thickness (Tb.Th), trabecular number (Tb.N), the ratio of osteoid volume to tissue volume (OV/TV), osteoid thickness (O.Th), the ratio of osteoid surface to bone surface (OS/BS), the ratio of osteoblast surface to bone surface (Ob.S/BS), and the number of osteoblast per unit of bone surface (N.Ob/BS), and decreased trabecular separation (Tb.Sp), the ratio of eroded surface to bone surface (ES/BS), the ratio of osteoclast surface to bone surface (Oc.S/BS), and number of osteoclast per unit of bone surface (N.Oc/BS), compared to untreated mice. Furthermore, histological sections of the femurs showed that oral administration of petunidin to sRANKL-induced osteopenic mice increased the size of osteoblasts located along the bone surface and the volume of osteoid was consistent with the in vitro osteoblast differentiation and MMP inhibition. These results suggest that petunidin is a promising natural agent to improve sRANKL-induced osteopenia in mice through increased osteoid formation, reflecting accelerated osteoblastogenesis, concomitant with suppressed bone resorption.

Unique primed status of microglia under the systemic autoimmune condition of lupus-prone mice.

BACKGROUND: Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by the production of various autoantibodies. This disease causes disabling neuropsychiatric symptoms even in the absence of apparent inflammation in the central nervous system (CNS), but the mechanisms involved remain unknown. Innate immune-mediated inflammation has attracted attention as a pathogenic mechanism in neuropsychiatric diseases. METHODS: We investigated the CNS of lupus-prone mice focusing on innate immunity. Three strains of lupus-prone mice, FcγRIIB-/-Yaa, an F1 hybrid of NZB and NZW (NZB/NZW) mice, and MRL/Faslpr (MRL/lpr) mice were used to analyze CNS immunopathology. RESULTS: Flow cytometry analysis demonstrated the numbers of brain CD45+ cells were increased compared with controls in lupus-prone mice. Upregulation of MHC class I and PDCA1 was observed in microglia and CD11b+ myeloid cells of lupus-prone mice, indicating they were activated in response to interferons (IFN). Microglial gene expression analysis of FcγRIIB-/-Yaa mice revealed the upregulation of IFN-responsive genes and inflammation-related genes including Axl, Clec7a, and Itgax, which were previously reported in neurodegenerative conditions and primed conditions. Upregulated chemokine gene expressions including Ccl5 and Cxcl10 were concurrent with increased numbers of T cells and monocytes, especially Ly6Clo monocytes in the CNS. Upregulation of Axl, Clec7a, Itgax, Ccl5, and Cxcl10 was also observed in NZB/NZW mice, indicating common lupus pathology. The primed status of microglia in FcγRIIB-/-Yaa mice was also demonstrated by morphological changes such as enlarged cell bodies with hypertrophic processes, and hyperreactivity to lipopolysaccharide. Immunohistochemistry of FcγRIIB-/-Yaa mice indicated reactive responses of astrocytes and vascular endothelium. Behavioral studies of FcγRIIB-/-Yaa mice revealed depressive-like behavior and heat hyperalgesia in the forced swim test and the tail-flick test, respectively. CONCLUSIONS: Our data indicated that microglia in lupus exhibit a unique primed phenotype characterized by the upregulated expressions of neurodegeneration-related genes and IFN-responsive genes. Interaction with peripheral cells and brain resident cells was presumed to orchestrate neuroinflammation. Targeting innate immune cells, such as microglia and monocytes, may be a promising therapeutic approach for neuropsychiatric SLE.

Correction: Development and Validation of a Clinical Prediction Rule for Bacteremia among Maintenance Hemodialysis Patients in Outpatient Settings.

[This corrects the article DOI: 10.1371/journal.pone.0169975.].

Association Between Staphylococcus aureus Bacteremia and Hospital Mortality in Hemodialysis Patients With Bloodstream Infection: A Multicenter Cohort From Japanese Tertiary Care Centers.

Multiple studies have shown that Staphylococcus aureus bacteremia (SAB) has been a major cause of death in hemodialysis patients. We examined whether SAB is a risk for mortality among chronic hemodialysis patients in Japan where the standard vascular access is arteriovenous fistula (AVF). This was a multicenter, retrospective study of maintenance hemodialysis patients with bloodstream infection (BSI) from 2011 to 2013 at tertiary care centers in Japan. The endpoint was hospital mortality. Our cohort contained 32 SAB cases (14 MRSA and 18 MSSA) and 42 non-SAB cases. Hospital mortality was higher among SAB cases than non-SAB cases (46.9% vs. 23.8%, P = 0.038). In patients with BSI, SAB was significantly associated with hospital mortality after adjustment for potential confounders, including type of vascular access (OR 3.26). S. aureus was the leading cause of BSI and hospital mortality among this cohort. Therefore, initial empiric treatment should cover for S. aureus.