Relapse in patients with antineutrophil cytoplasmic antibody-associated vasculitis undergoing dialysis: a single-centre retrospective study in South Korea.

OBJECTIVES: The disease activity of antineutrophil cytoplasmic antibody-associated vasculitis (AAV) can decrease after dialysis, and relapse after dialysis is not well-studied. We investigated the clinical manifestations and factors associated with relapse in patients with AAV undergoing dialysis. METHODS: This retrospective study included data of patients with AAV undergoing dialysis due to renal involvement from July 2005 to March 2021 in a single tertiary centre in Seoul, Korea. Cox regression analysis was performed to identify relapse-associated factors. RESULTS: The study cohort included 38 patients with a median age of 64.0 years; 28 (73.7%) were female, and 35 (92.1%) patients were diagnosed with microscopic polyangiitis (MPA). At diagnosis, the mean Birmingham vasculitis activity score (BVAS) was 18.3 and 66.3% of the patients exhibited pulmonary manifestations. During follow-up, 12 patients experienced AAV relapse, including nine patients with diffuse alveolar haemorrhage (DAH), two patients with aggravated interstitial lung disease, and one patient with DAH accompanied with neuropathy. Clinical features including age, sex, and baseline BVAS did not significantly differ between the relapse and non-relapse groups. By univariable analysis, lung infiltration, DAH, corticosteroid pulse therapy for induction, and mean corticosteroid dose were significantly associated with relapse. Multivariable analysis revealed that DAH (adjusted hazard ratio 5.509, 95% CI 1.569-19.339; P=0.008) and mean corticosteroid dose (adjusted hazard ratio 1.381, 95% CI 1.161-1.642; P<0.001) were significantly associated with relapse. CONCLUSIONS: In patients with AAV undergoing dialysis, DAH and mean corticosteroid dose were significantly associated with relapse, highlighting the importance of close monitoring.

Circulating and renal fibrocytes are associated with interstitial fibrosis in lupus nephritis.

OBJECTIVES: Fibrocytes, the extracellular matrix-producing cells derived from bone marrow progenitors, contribute to organ fibrosis. We investigated the presence and characteristics of fibrocytes in the peripheral blood and kidney of patients with lupus nephritis (LN), and the association of the abundance of fibrocytes with renal tubular epithelial cells (RTECs) in LN fibrogenesis. METHODS: Fibrocytes were identified with type I collagen (colI), α-smooth muscle actin (α-SMA), CD34 and CD45 using flow cytometry and confocal imaging. The associations between the levels of fibrocytes and pathological features of patients with LN were analysed. The contribution of RTECs to fibrocyte generation was determined using LN sera-treated HK-2 cells. RESULTS: Spindle-shaped fibrocytes (colI+α-SMA+CD34+CD45+ cells) were present in the peripheral blood and their abundance was especially high in LN patients with interstitial fibrosis compared with healthy control. Renal fibrocytes (colI+α-SMA+CD45+ cells) were found in the tubulointerstitium in patients with LN, and their numbers were significantly associated with the degrees of chronicity indices including interstitial fibrosis and renal dysfunction. Stimulation of peripheral blood mononuclear cells with supernatants from LN serum-treated HK-2 cells led to a significant generation of fibrocytes, which was abrogated by the addition of IL-6 neutralizing antibody. CONCLUSION: Fibrocytes were significantly increased in the blood and kidney tissue of patients with LN, especially those with interstitial fibrosis. Fibrocytes could be differentiated from blood cells, with an active contribution from RTECs. Our results show a possible link between fibrocytes and tubulointerstitial fibrosis, which may serve as a novel therapeutic target for LN fibrogenesis.

Incidence of and risk factors for myelodysplastic syndromes in patients with rheumatologic diseases.

OBJECTIVE: We investigated the incidence rate and risk factors of myelodysplastic syndromes (MDS) in patients with rheumatologic disease. METHODS: We conducted a retrospective cohort study of patients who were diagnosed with rheumatologic diseases at a tertiary-care hospital between May 2009 and July 2022 and identified the patients who were subsequently diagnosed with MDS. Each patient with MDS was matched with five age- and sex-matched controls chosen from the cohort of patients with each specific rheumatologic disease. RESULTS: During a total follow-up of 55 841 person-years (PY), MDS occurred in 64 patients, yielding an incidence rate of 1.15/1000 PY (median age, 57.0 [IQR, 41.0-69.0]; median duration to MDS diagnosis, 6.5 years [IQR, 3.0-9.0]). In an age-matched analysis, systemic lupus erythematosus (SLE) was a significant risk factor for MDS (adjusted hazard ratio, 2.61 [CI, 1.19-36.06], P= 0.01). Refractory cytopenia with multilineage dysplasia was the most common phenotype of MDS (35.9%), and more than half of the patients had karyotypes with favorable prognoses (54.7%). Compared with matched controls, rheumatoid arthritis, SLE, and ankylosing spondylitis patients with MDS had lower levels of haemoglobin at the time of diagnosis of rheumatologic disease. Furthermore, the MDS patients with SLE and Behcet's disease had higher levels of glucocorticoid use in terms of frequency of use or mean dose than the control patients. CONCLUSION: SLE is a significant risk factor for MDS among patients with rheumatologic diseases. A lower haemoglobin level at the time of diagnosis of rheumatologic disease was associated with the future development of MDS.

Prognostic value of proteinuria monitoring in anti-neutrophil cytoplasmic antibody-associated vasculitis.

OBJECTIVE: To determine the prognostic significance of proteinuria monitoring in patients with anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV). METHODS: We retrospectively analyzed the data of kidney biopsy-confirmed patients with AAV. Proteinuria was evaluated by a urine dipstick test. Poor renal outcome was defined as stage 4/5 chronic kidney disease (CKD) (estimated glomerular filtration rate < 30 mL/min/1.73 m2). RESULTS: We enrolled 77 patients with a median follow-up duration of 36 months (interquartile range, 18-79) in this study. Excluding 8 patients on dialysis at 6 months, 59/69 (85.5%) achieved remission after induction therapy. Patients were then divided into two groups according to the presence of proteinuria at 6 months after induction therapy (n = 29 with proteinuria, 40 without proteinuria). There was no significant difference in the rate of relapse or death according to the presence of proteinuria (p = 0.304 relapse, 0.401 death). In contrast, patients with proteinuria had significantly lower kidney function than those without proteinuria (41 vs. 53.5 mL/min/1.73 m2, p = 0.003). Multivariate analysis revealed that eGFR values at 6 months (hazard ratio [HR] 0.925; 95% CI 0.875-0.978, p = 0.006) and proteinuria at 6 months (HR 4.613; 95% CI 1.230-17.298, p = 0.023) were significantly associated with stage 4/5 CKD. CONCLUSION: The presence of proteinuria at 6 months after induction therapy and low renal function was significantly associated with a higher risk of stage 4/5 CKD in patients with AAV. Monitoring for proteinuria after induction therapy may help predict poor renal outcomes in patients with AAV.

Clinical features of systemic lupus erythematosus patients with splenomegaly: focussed on the cytopenias.

This study aimed to investigate the clinical features of splenomegaly, mainly focussing on cytopenia, in patients with systemic lupus erythematosus (SLE). Cytopenia was commonly observed in 111 SLE patients with splenomegaly (n = 79, 71.2%). During the follow-up period, two patients developed haematologic malignancy after the diagnosis of SLE and splenomegaly, but no patients experienced severe complications (e.g. splenic rupture) related to splenomegaly.

When MRI would be useful in patients without evidence of sacroiliitis on radiographs?

We aimed to identify when magnetic resonance imaging (MRI) would be useful to diagnose patients with suspected axial spondyloarthropathy (AxSpA) without evidence of sacroiliitis on radiographs. We retrospectively reviewed electronic medical records of patients who underwent pelvis MRI after radiographs at the rheumatology clinic in a single tertiary center in Korea. Patients underwent imaging from January 2020 to July 2022. We collected data including complete blood count, erythrocyte sedimentation rate, C-reactive protein (CRP), human leukocyte antigen (HLA)-B27, history of acute anterior uveitis (AAU), peripheral arthritis, dactylitis, inflammatory bowel disease (IBD), enthesopathy, and psoriasis. A total of 105 patients who showed no evidence of sacroiliitis on radiographs were included. The median age of patients was 41.0 years, and 44.8% were male. Of them, 34 showed sacroiliitis on MRI (group 1), and 71 showed no evidence of sacroiliitis even on MRI (group 2). Known AxSpA-related clinical features including AAU, peripheral arthritis, dactylitis, IBD, enthesopathy, and psoriasis were not different between the two groups. HLA-B27 positivity (79.4% vs. 40.0%, p < 0.001), median white blood cell count (7700 vs. 6300, p = 0.007), mean platelet count (307.7 ± 69.7 vs. 265.3 ± 68.9 × 103/µL, p = 0.005), and median CRP level (0.38 vs. 0.10, p = 0.001) showed significant differences between the two groups. In a multivariate analysis, HLA-B27 positivity and platelet count were significantly associated with sacroiliitis on MRI. In our cohort, sacroiliitis was observed on MRI in one-third of patients without radiographic evidence. MRI could be recommended to evaluate sacroiliitis in patients with positive HLA-B27 and a high platelet count.

Anti-S1/RBD-Specific Antibody Formation After SARS-CoV-2 Vaccination in Elderly Rheumatoid Arthritis Patients: Single-Center Prospective Observational Study.

BACKGROUND: The guidelines of coronavirus disease 2019 (COVID-19) vaccination in patients with rheumatoid arthritis (RA) have been continuously updated, with extensive discussion on the effectiveness of the COVID-19 booster vaccines and antibody generation associated with the different types of vaccine. We investigated the effects of the third dose of the mRNA vaccine on antibody titer and the factors associated with antibody production in patients with RA who had previously received two doses of the ChAdOx1-S nCoV-19 vaccine. METHODS: Between October 14, 2021 and June 17, 2022, two patient groups diagnosed with RA were recruited prospectively: one with two doses of ChAdOx1-S nCoV-19 and the second group with the additional third mRNA vaccine. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody titers were determined through semiquantitative anti-SARS-CoV-2 spike (S) electrochemiluminescence immunoassay. Antibody titers were compared in both groups considering clinical features and medications. Multivariate logistic regression was performed to identify the factors associated with antibody production. Also, we followed up the antibody titers of whom completed the 3rd mRNA vaccination. RESULTS: Among 261 patients, all patients were over 60 years old except for 7 patients and the average age was 65 years; 153 had completed two doses of ChAdOx1-S nCoV-19, while 108 patients had also received the third mRNA vaccine. The positive rates of anti-SARS-CoV-2 anti-S1/receptor binding domain-specific antibody (titer > 0.8 U/mL) were 97% (149/153) and 99% (107/108) respectively. However, positive rates for high antibody titer (> 250 U/mL) were found in only 31% (47/153) of group 1 but 94% (102/108) of group 2. Multivariate analysis revealed that corticosteroid use (odds ratio [OR], 0.35; 95% confidence interval [CI], 0.16-0.75), older age (OR, 0.91; 95% CI, 0.860-0.98), and male sex (OR, 0.23; 95% CI, 0.07-0.74) were associated with a lower rate of high antibody titer acquisition after two doses of ChAdOx1-S nCoV-19. Waning of antibody titers was observed in only two of 46 patients who followed up twice after the third mRNA vaccine inoculation. CONCLUSION: Our findings suggest that the third dose of the mRNA vaccine could be beneficial in RA patients with risk factors including older age, male sex, and corticosteroid use after two doses of ChAdOx1-S nCoV-19.

Automated quantification system predicts survival in rheumatoid arthritis-associated interstitial lung disease.

OBJECTIVE: The prognosis of RA-associated interstitial lung disease (RA-ILD) is difficult to predict because of the variable clinical course. This study aimed to determine the prognostic value of an automated quantification system (AQS) in RA-ILD. METHODS: We retrospectively analysed the clinical data and high-resolution CT (HRCT) images of 144 patients with RA-ILD. Quantitative lung fibrosis (QLF, sum of reticulation and traction bronchiectasis) and ILD [QILD; sum of QLF, honeycombing (QHC), and ground-glass opacity (QGG)] scores were measured using the AQS. RESULTS: The mean age was 61.2 years, 43.8% of the patients were male, and the 5-year mortality rate was 30.5% (median follow-up, 52.2 months). Non-survivors showed older age, higher ESR and greater AQS scores than survivors. In multivariable Cox analysis, higher QLF, QHC and QILD scores were independent prognostic factors along with older age and higher ESR. In receiver-operating characteristic curve analysis, the QLF score showed better performance in predicting 5-year mortality than the QHC and QGG scores but was similar to the QILD score. Patients with high QLF scores (≥12% of total lung volume) showed higher 5-year mortality (50% vs 17.4%, P < 0.001) than those with low QLF scores and similar survival outcome to patients with idiopathic pulmonary fibrosis (IPF). Combining with clinical variables (age, ESR) further improved the performance of QLF score in predicting 5-year mortality. CONCLUSION: QLF scores might be useful for predicting prognosis in patients with RA-ILD. High QLF scores differentiate a poor prognostic phenotype similar to IPF.

Pleuroparenchymal fibroelastosis in rheumatoid arthritis-associated interstitial lung disease.

BACKGROUND: Pleuroparenchymal fibroelastosis (PPFE) is a rare interstitial lung disease (ILD) featuring dense fibrosis of the visceral pleura and subpleural parenchyma, mostly in the upper lobes. PPFE can present in other ILDs, including rheumatoid arthritis-associated ILD (RA-ILD). The aim of this retrospective study was to investigate the prevalence and clinical implications of coexistent PPFE in RA-ILD. METHODS: Overall, 477 patients with RA-ILD were recruited from two cohorts; their clinical data and HRCT images were analysed. The criteria for diagnosing PPFE were (1) pleural thickening with bilateral subpleural dense fibrosis in the upper lobes, (2) evidence of disease progression, and (3) absence of other identifiable aetiologies. RESULTS: The median follow-up duration was 3.3 years. The mean age of the patients was 63.4 years, and 60.0% were women. PPFE was identified in 31 patients (6.5%). The PPFE group showed significantly lower body mass index and forced vital capacity (FVC) and more frequent usual interstitial pneumonia (UIP)-like pattern on HRCT than no-PPFE group. The risk factors for all-cause mortality were older age, lower FVC, and the presence of UIP-like pattern on HRCT; PPFE was not significantly associated with mortality in both all patients and a subgroup with a UIP-like pattern. The presence of PPFE was associated with a significantly increased risk of pneumothorax and greater decline in diffusing capacity. CONCLUSIONS: PPFE was not rare in patients with RA-ILD and was significantly associated with an increased risk of pneumothorax and greater lung function decline, though we found no significant association with mortality.

Renal outcomes of transient proteinuria in patients with systemic lupus erythematosus treated with corticosteroid therapy alone.

OBJECTIVES: To examine the long-term renal outcomes of systemic lupus erythematosus (SLE) patients with transient proteinuria. METHODS: The medical records of SLE patients who showed improvement in proteinuria (urine protein/creatinine ratio < 500 mg/g) after receiving corticosteroid therapy without immunosuppressants were reviewed. RESULTS: A total of 38 patients (mean creatinine: 0.74 ± 0.33 mg/dl) showed an improvement of proteinuria (1361 ± 1053 mg/g to 289 ± 125 mg/g) after receiving corticosteroid therapy alone for a median of 25 days (IQR, 10-55). After follow-up (median, 23 months [IQR, 15-121]), 25 (65%) patients maintained the resolution of proteinuria without renal dysfunction. The remaining 13 (34%) patients experienced a relapse of proteinuria during a median follow-up of 13.9 months from baseline (IQR, 1.6-25). There was no significant difference in the baseline laboratory data according to the occurrence of proteinuria relapse, but longer SLE disease duration at baseline was associated with the risk of proteinuria relapse (HR, 1.007; p = 0.033). Of the patients who underwent renal biopsy with proteinuria relapse, class II (53%) lupus nephritis was the most common pathology. None progressed to end-stage renal disease during an additional long-term further follow-up of median 33 months (IQR, 22-49) after proteinuria relapse. CONCLUSION: Two-thirds of SLE patients who showed improvement in proteinuria after corticosteroid alone maintained the non-proteinuric state without renal dysfunction. Thus, performing a kidney biopsy at the first onset of proteinuria could be delayed in patients who show an improvement in proteinuria after treatment with corticosteroids.

Angiographic patterns and temporal changes of arterial lesions in Behcet's disease.

BACKGROUND: Behcet's disease (BD) can entail vascular involvement in various forms including aneurysm. We evaluated the angiographic patterns and changes in arterial lesions over time in BD patients with arterial involvement. METHODS: We reviewed the medical records of BD patients diagnosed with arterial lesions between 1995 and 2018. Angiographic patterns were categorized as stenosis, occlusion, dilatation, or aneurysm. Patients were divided according to symptom duration (<5, 5-10, >10 years). Cox proportional-hazards model was used to evaluate the risk factors for vascular progression. RESULTS: 47 BD patients had arterial involvement in the following patterns: aneurysm (n = 31), stenosis (n = 17), dilatation (n = 13), and occlusion (n = 8). Aneurysm (70.8%) was the most common pattern in 24 patients with short (<5 years) symptom duration. Stenosis was more common (50.0%) in 12 patients with longer symptom durations (>10 years). In 23 patients with follow-up imaging (median, 5.7 years), eight (34.8%) developed 11 new lesions: stenosis (n = 5), dilatation (n = 1), and aneurysm (n = 5). One stenotic lesion progressed to occlusion, and two dilated lesions progressed to aneurysms. Lower extremity involvement and methotrexate use were associated with arterial progression, with hazard ratios of 5.716 (p = 0.029) and 0.101 (p = 0.049), respectively. CONCLUSION: In BD patients with arterial involvement, aneurysm was the most common pattern in earlier stages of BD, while stenosis was more common in later stages of BD. Methotrexate use was associated with lower risk of arterial lesion progression.

Predictive Factors for Rheumatoid Arthritis Flare After Switching From Intravenous to Subcutaneous Formulation of Tocilizumab in Real-World Practice.

BACKGROUND: To evaluate the incidence and related factors of rheumatoid arthritis (RA) flares after switching from intravenous tocilizumab (TCZ-IV) to subcutaneous tocilizumab (TCZ-SC) injection in stable RA patients. METHODS: We retrospectively evaluated the medical records of stable RA patients who used TCZ-IV for more than 6 months and switched to TCZ-SC between January 2013 and April 2020. RA flare was defined as an increase of more than 1.2 in the RA disease activity as assessed by the disease activity score in 28 joints. The factors associated with RA flare were evaluated by logistic regression analysis. RESULTS: Among 106 patients treated with TCZ-IV for > 6 months, 37 patients were switched to TCZ-SC after the acquisition of remission or low disease activity. RA flares occurred in 11 (29.7%) of patients who switched TCZ-SC. Results from the multivariable logistic analysis revealed that the dose of TCZ-IV per weight at switching (odds ratio [OR], 20.70; 95% confidence interval [CI], 2.22-192.84; P = 0.008) and methotrexate (MTX) non-use (OR, 8.53; 95% CI, 1.21-60.40; P = 0.032) were associated with the risk of RA flares after switching to TCZ-SC. Interestingly, most patients who switched back to TCZ-IV had their RA activity controlled again. CONCLUSION: MTX non-use and high dose of TCZ-IV per weight were associated with a risk of RA flare after switching to TCZ-SC. RA patients with these factors need to be carefully observed for flare after switching from TCZ-IV to TCZ-SC.

Comparative efficacy of low-dose versus regular-dose colchicine to prevent flares in gout patients initiated on urate-lowering therapies.

OBJECTIVE: The objective of this study was to compare the prophylactic effect of regular-dose (RD, 1.2 mg/day) vs low-dose (LD, 0.6 mg/day) colchicine on gout flare when initiating urate-lowering therapy. METHODS: In this retrospective cohort study, we included gout patients who were initiated on either allopurinol or febuxostat, in combination with colchicine therapy and followed them up for 3 months. We analysed the rates of gout flare and adverse events according to the dose of colchicine. We performed the inverse probability of treatment weighting (IPTW) and weighted logistic regression analysis to assess the treatment effect. Analysis of gout flares and adverse events was performed on an intention-to-treat (ITT) and per-protocol (PP) basis. RESULTS: Of the total of 419 patients with gout, 177 patients (42.2%) received LD colchicine, whereas 242 patients (57.8%) received RD colchicine. Lower BMI and estimated glomerular filtration rate, and higher incidence of cardiovascular disease were seen in the LD group than in the RD group. In IPTW-adjusted analysis, events of gout flare were not significantly different between the LD and RD groups [ITT: 14.3% vs 11.3%; odds ratio (OR): 1.309, 95% CI: 0.668, 2.566, P = 0.432; PP: 15.3% vs 10.0%; OR: 1.623, 95% CI: 0.765, 3.443, P = 0.207]. However, LD colchicine was associated with a lower rate of adverse events than RD colchicine [ITT: 8.2% vs 17.9%; OR: 0.410, 95% CI: 0.217, 0.777; P < 0.05; PP: 8.4% vs 17.2%; OR: 0.442, 95% CI: 0.223, 0.878; P < 0.05]. CONCLUSION: Our data suggest that LD colchicine can adequately prevent gout flare with fewer adverse events compared with RD colchicine.

Urine ß-2-glycoprotein 1 as a biomarker for diagnosis of systemic lupus erythematosus.

OBJECTIVE: The need for a biomarker with robust sensitivity and specificity in diagnosing systemic lupus erythematosus (SLE) remains unmet. Compared with blood samples, urine samples are more easily collected; thus, we aimed to identify such a biomarker based on urinary proteomics which could distinguish patients with SLE from healthy controls (HCs). METHODS: Urine samples were collected from 76 SLE patients who visited rheumatology clinic in 2019 at Asan medical center and from 25 HCs. Urine proteins were analyzed using sequential windowed acquisition of all theoretical fragment ion spectra-mass spectrometry, and the candidate marker was confirmed by enzyme-linked immunosorbent assay (ELISA). Receiver operating characteristic curve analysis was used to determine the diagnostic value of the candidate biomarker. RESULTS: Of 1157 proteins quantified, 153 were differentially expressed in urine samples from HCs. Among them were previously known markers including α-1-acid glycoprotein 1, α-2-HS-glycoprotein, ceruloplasmin, and prostaglandin-H2 D-isomerase. Moreover, the amount of ß-2 glycoprotein (APOH) was increased in the urine of patients with SLE. The ELISA results also showed the level of urine APOH was higher in patients with SLE than in HCs and patients with rheumatoid arthritis. Moreover, the level was not different between SLE patients with and without nephritis. The urine APOH had an area under the curve value of 0.946 at a cut-off value of 228.53 ng/mg (sensitivity 91.5%, specificity 92.0%) for the diagnosis of SLE. CONCLUSION: The results indicate that the urine APOH level can be an appropriate screening tool in a clinical setting when SLE is suspected.

Immunological characteristics and possible pathogenic role of urinary CD11c+ macrophages in lupus nephritis.

OBJECTIVES: Kidney-infiltrating immune cells can contribute to the pathogenesis of lupus nephritis (LN). We investigated the immunological characteristics of CD11c+ macrophages and their functions associated with the pathogenesis of LN. METHODS: CD11c+ macrophages were examined in the urine samples of patients with LN. Phenotypic markers and pro-inflammatory cytokine expression levels were analysed by flow cytometry. To determine the origin of urinary macrophages, peripheral monocytes were treated with sera from patients with systemic lupus erythematosus (SLE). The pathogenic role of CD11c+ macrophages in tubulointerstitial damage was investigated using SLE sera-treated monocytes and HK-2 cells. RESULTS: Urinary CD11c+ macrophages expressed pro-inflammatory cytokines, such as IL-6 and IL-1ß, and resembled infiltrated monocytes rather than tissue-resident macrophages with respect to surface marker expression. CD11c+ macrophages had high expression levels of the chemokine receptor CXCR3, which were correlated with cognate chemokine IP-10 expression in urinary tubular epithelial cells. When treated with sera from SLE patients, peripheral monocytes acquired the morphological and functional characteristics of urinary CD11c+ macrophages, which was blocked by DNase treatment. Finally, SLE sera-treated monocytes induced fibronectin expression, apoptosis and cell detachment in HK-2 cells via production of IL-6. CONCLUSION: CD11c+ macrophages may be involved in the pathogenesis of tubulointerstitial injury in LN.

Plasma immunoglobulin binding protein 1 as a predictor of development of lupus nephritis.

Objective: Urine levels of immunoglobulin binding protein 1 (IGBP1) are increased in patients with lupus nephritis (LN) compared with systemic lupus erythematosus (SLE) patients without nephritis. However, the clinical significance of IGBP1 level in plasma is unclear. We aimed to evaluate whether the plasma level of IGBP1 can predict future development of LN in SLE patients without nephritis. Methods: Forty-three SLE patients without nephritis were followed for 5 years. Plasma IGBP1 levels were measured using ELISA, and clinical and laboratory data were obtained at study entry. Development of LN was confirmed by renal biopsy. Cox regression analysis was performed to identify factors associated with development of LN, and receiver operating characteristic curve analysis was used to determine the predictive value of each factor. Results: Of the total 43 patients, eight (18.6%) developed LN during the follow-up period. Compared with patients who did not develop LN, those who developed LN had higher levels of plasma IGBP1 (6.3 ng/ml (range 4.3­9.6 ng/mL) vs. 13.3 ng/ml (range 7.2­31.3 ng/ml); p=0.023). In the Cox regression analysis, higher CRP (hazard ratio (HR)=1.325, 95% confidence interval (CI) 1.073­1.637, p=0.009), anti-dsDNA antibody (Ab; HR=1.066, 95% CI 1.012­1.124, p=0.017) and plasma IGBP1 (HR=1.091, 95% CI 1.034­1.152, p=0.002) were associated with future development of LN. Among these factors, anti-dsDNA Ab (area under the curve (AUC)=0.893) had the highest predictive value followed by plasma IGBP1 (AUC=0.761) and CRP (AUC=0.634). A combination of anti-dsDNA Ab and plasma IGBP1 as a composite predictor was highly specific (97%) for predicting the development of LN. Conclusions: Plasma IGBP1 can be used complementarily with anti-dsDNA Ab for detecting SLE patients at a higher risk of developing LN.

Factors associated with aggravation of tubulointerstitial damage on repeated biopsies in lupus nephritis patients with treatment failure.

OBJECTIVES: Tubulointerstitial damage in lupus nephritis (LN) is an important predictor of renal prognosis. Here, we investigated the factors associated with aggravation of tubulointerstitial damage in patients with LN. METHODS: Patients with LN, who underwent repeated renal biopsy due to treatment failure at a tertiary referral hospital between 1997 and 2017 were identified. Clinicopathologic and laboratory data were collected. Aggravation of tubulointerstitial damage (tubular atrophy and/or interstitial fibrosis) was defined as progression of severity from none-to-mild to moderate-to-severe. Factors associated with aggravation of tubulointerstitial damage were evaluated using logistic regression analysis. RESULTS: A total of 52 LN patients were included for analysis. Aggravation of tubulointerstitial damage at the second renal biopsy was observed in 19 (36.5%) patients. In multivariable logistic regression analysis, use of hydroxychloroquine (adjusted OR 0.215, 95% CI 0.049-0.941, p=0.041) was inversely associated with aggravation of tubulointerstitial damage, and higher renal component of systemic lupus erythematosus disease activity index (SLEDAI) at first biopsy (adjusted OR 1.331, 95% CI 1.083-1.636, p=0.007) was associated with aggravation of tubulointerstitial damage. In terms of use of HCQ, both length of treatment with HCQ (adjusted OR 0.974, 95% CI 0.951-0.998, p=0.036) and cumulative dose of HCQ (log transferred value) (adjusted OR 0.485, 95% CI 0.262-0.896, p=0.020) were inversely associated with aggravation of tubulointerstitial damage. CONCLUSIONS: Use of hydroxychloroquine was associated with lower risk of aggravation in tubulointerstitial damage, and higher renal component of SLEDAI at first renal biopsy was associated with higher risk of aggravation in tubulointerstitial damage.

Methotrexate-related toxicity in patients with rheumatoid arthritis and renal dysfunction.

There are limited studies regarding the safety of methotrexate (MTX) in patients with reduced renal function. This study aimed to investigate methotrexate (MTX)-related toxicity in patients with rheumatoid arthritis (RA) and renal dysfunction. This retrospective cohort study included patients with RA and renal dysfunction. Renal dysfunction was defined as an estimated glomerular filtration rate (eGFR) of < 60 mL/min/1.73 m2. We classified the patients into two groups according to the onset of renal dysfunction: newly and previously developed group. MTX-associated toxicity included renal toxicity, hepatotoxicity, serious infection, pancytopenia, leukopenia, thrombocytopenia and mucositis. Cox analysis was performed to determine the factors associated with toxicity. The study included 120 patients with RA and renal dysfunction receiving MTX (66: newly developed; 54: previously developed). The median eGFR was 52.1 mL/min/1.73 m2 [IQR 47.1-57.3]. Thirty-five patients (29.2%) experienced toxicity, and the median time to toxicity events was 23 months (IQR 10-57). Toxicity was distributed as follows: leukopenia (10%, 12/120), renal toxicity (5.8%, 7/120), hepatotoxicity (7.5%, 9/120), serious infection (8.3%, 10/120), pancytopenia (5.0%, 6/120), thrombocytopenia (5.8%, 7/120), and mucositis (5.8%, 7/120). The toxicity rate did not differ significantly between newly and previously developed group [23/66 (34.8%) vs. 12/54 (22.2%), P = 0.130]. Multivariate analysis revealed that hydroxychloroquine use (HR 0.425, 95% CI 0.212-0.853, P = 0.016), baseline eGFR (HR 0.938, 95% CI 0.890-0.988, P = 0.015) and being female (HR 10.538, 95% CI 1.375-80.793, P = 0.023) were associated with MTX-related toxicity. Toxicity occurred in approximately 30% of patients with RA and renal dysfunction receiving MTX treatment. Hydroxychloroquine use exhibited a protective effect against MTX-associated toxicity development.

Effect of TNF inhibitors on bone mineral density in rheumatoid arthritis patients receiving bisphosphonate: a retrospective cohort study.

We aimed to determine whether tumor necrosis factor inhibitors (TNFi) have beneficial effects on bone mineral density (BMD) in rheumatoid arthritis (RA) patients with osteoporosis receiving bisphosphonate. A total of 199 RA patients, who were newly diagnosed with osteoporosis and receiving bisphosphonate between January 2005 and March 2017, were reviewed. Changes in BMD after 1 year were compared between patients treated with and without TNFi. The inverse probability of treatment weighting (IPTW) method using the propensity score was performed to minimize confounding factors, and logistic regression analysis was applied to identify any factors associated with significant BMD improvement (≥ 3%) at the lumbar spine and femur neck. Among patients receiving bisphosphonate, 29 were exposed to TNFi, and 170 patients were not exposed. The percentage change in BMD and the proportion of significant improvements at the lumbar spine and femur neck were similar between patients treated with and without TNFi, before and after IPTW adjustment. In addition, the disease activity score 28 (DAS28) with three variables [adjusted odds ratio (OR) 0.741, 95% confidence interval (CI) 0.592-0.927, p = 0.009] and cumulative steroid dose (adjusted OR 0.639, 95% CI 0.480-0.851, p = 0.002) were inversely associated with an improvement in BMD. Conversely, TNFi use was not associated with any improvement in BMD after adjustment by IPTW using the propensity score. TNFi did not influence BMD improvement in RA patients with osteoporosis receiving bisphosphonate, suggesting that TNFi cannot be considered as a preferred therapeutic option for increasing BMD.

Clinical features and risk of recurrence of acute calcium pyrophosphate crystal arthritis.

OBJECTIVES: It is unclear whether attack recurrence rates are similar between acute calcium pyrophosphate (CPP) crystal arthritis and gout. This study compared the clinical features and recurrence rates of both conditions. METHODS: In this retrospective study, we reviewed 106 patients with acute CPP crystal arthritis (based on the presence of CPP crystals and/or chondrocalcinosis) and 173 patients with gout (based on the presence of monosodium urate crystals). We analysed clinical variables and compared them between the two conditions. We identified factors associated with the recurrence of acute CPP crystal arthritis. RESULTS: Patients with acute CPP crystal arthritis were older (76.5 vs. 62 years, p<0.001) and female (69.8% vs. 6.9%, p<0.001); they had a lower body mass index (22.3 vs. 23.7, p=0.002), lower renal insufficiency rate (27.4% vs. 41.6%, p=0.016), and higher rate of preceding infection (22.6% vs. 11.0%, p=0.009) than those with acute gout. Recurrence rates were similar between the groups (19.1% vs. 22.9%, p=0.562). Use of proton pump inhibitors (PPIs) [hazard ratio (HR), 5.625; 95% CI, 1.672-18.925; p=0.005] and warfarin (HR, 7.301; 95% CI, 1.930-27.622; p=0.003) or exposure to chemotherapy (HR, 5.663; 95% CI, 1.180-27.169; p=0.03) were associated with acute CPP crystal arthritis recurrence. CONCLUSIONS: Acute CPP crystal arthritis was more common than acute gout in older women with preserved renal function. Physicians should be aware of the association between recurrence and PPI, warfarin, or chemotherapy use in these patients.