Chinese SLE treatment and research group registry: III. association of autoantibodies with clinical manifestations in Chinese patients with systemic lupus erythematosus

The additional role of anti-nucleosome antibodies in the prediction of renal damage in systemic lupus erythematosus based on CSTAR (XXV)

OBJECTIVES

The predominant determinant of an unfavorable prognosis among Systemic Lupus Erythematosus (SLE) patients resides in the irreversible organ damage. This prospective cohort study aimed to identify the additional value of anti-nucleosome antibodies on organ damage accumulation in SLE patients.

METHODS

Based on the Chinese SLE Treatment and Research group (CSTAR) registry, demographic characteristics, autoantibodies profiles, and clinical manifestations were collected at baseline. Follow-up data were collected by reviewing clinical records.

RESULTS

Of 2481 SLE patients with full follow-up data, 663 (26.7%) were anti-nucleosome antibodies positive and 1668 (68.0%) were anti-dsDNA antibodies positive. 764 (30.8%) patients developed new organ damage during a mean follow-up of 4.31 ± 2.60 years. At baseline, patients with positive anti-nucleosome antibodies have a higher rate of lupus nephritis (50.7% vs 36.2%, p < .001). According to the multivariable Cox regression analysis, both anti-nucleosome (HR = 1.30, 95% CI, 1.09-1.54, p < .001) and anti-dsDNA antibodies (HR=1.68, 95% CI, 1.38-2.05, p < .001) were associated with organ damage accumulation. Anti-nucleosome (HR = 2.51, 95% CI, 1.81-3.46, p < .001) and anti-dsDNA antibodies (HR = 1.69, 95% CI, 1.39-2.06, p < .001) were independent predictors for renal damage. Furthermore, the combination of the two antibodies can provide more accurate information about renal damage in overall SLE patients (HR = 3.19, 95% CI, 2.49-4.10, p < .001) and patients with lupus nephritis at baseline (HR = 2.86, 95% CI, 2.29-3.57, p < .001).

CONCLUSION

Besides anti-dsDNA antibodies, anti-nucleosome antibodies can also provide information about organ damage accrual during follow-up. The ability of co-positivity of anti-nucleosome and anti-dsDNA antibodies in predicting renal damage may lead to additional benefits in the follow-up of these patients.

Association of anti-Ro52 autoantibody with interstitial lung disease in autoimmune diseases: a systematic review and meta-analysis

OBJECTIVES

Interstitial lung disease (ILD) is an important manifestation of autoimmune diseases that can lead to morbidity and mortality. Although several autoantibodies have been linked with ILD presentation and adverse outcomes, the association of anti-Ro52 antibody with ILD is less studied. Hence, we investigated this association in various autoimmune diseases in the current study.

DESIGN

We designed a systematic review and meta-analysis and did a comprehensive search from inception until 2 January 2023.

DATA SOURCES

A systematic search was conducted in four electronic databases: PubMed, Web of Science, Scopus and Embase.

ELIGIBILITY CRITERIA

Observational studies that reported ILD diagnosis (outcome) and anti-Ro antibody (exposure) status in any autoimmune conditions (population) were included. The association between rapidly progressive ILD (RP-ILD) and anti-Ro52 was studied in idiopathic inflammatory myopathies (IIM).

DATA EXTRACTION AND SYNTHESIS

Collected data included study characteristics and ORs with 95% CIs. Quality assessment was performed using a modified version of the Newcastle-Ottawa Scale for cross-sectional studies. Random effects meta-analysis was used to pool the effect estimates.

RESULTS

A total of 2353 studies were identified, from which 59 articles met the eligibility criteria. Anti-Ro52/SSA positivity was associated with ILD in all autoimmune disease subgroups: IIM (OR=3.08; 95% CI: 2.18 to 4.35; p value<0.001; I2=49%), systemic lupus (OR=2.43; 95% CI: 1.02 to 5.79; p=0.046; I2=71%), Sjogren (OR=1.77; 95% CI: 1.09 to 2.87; p=0.021; I2=73%), systemic sclerosis (OR=1.71; 95% CI: 1.04 to 2.83; p=0.036; I2=43%), mixed connective tissue disease (OR=3.34; 95% CI: 1.82 to 6.13; p<0.001; I2=0%). Additionally, anti-Ro52-positive myopathy patients were more likely to have simultaneous RP-ILD (OR=2.69; 95% CI:1.50 to 4.83; p<0.001; I2=71%).

CONCLUSION

Anti-Ro52/SSA positivity is associated with a higher frequency of ILD diagnosis in various autoimmune diseases. Anti-Ro52/SSA is also linked with a more severe lung involvement (RP-ILD). Future studies can investigate the benefits of screening for anti-Ro52 and its association with ILD development.

PROSPERO REGISTRATION NUMBER

CRD42022381447.

Serological and clinical associations of autoantibodies in Chinese patients with new-onset systemic lupus erythematosus

To study the clinical significance of autoantibodies in Chinese patients with new-onset systemic lupus erythematosus (SLE), we enrolled 526 new-onset patients who met the 1997 Updated American College of Rheumatology SLE Classification Criteria for a retrospective cohort study. Chi-square test and Wilcoxon rank-sum test were used to detect the relationship of autoantibodies with clinical manifestations and serological results respectively. Our results demonstrated that the positive rate of anti-ribosomal P protein (anti-P) antibody in female patients was higher than that in male patients (41.2% vs. 22%, P = 0.008). Patients with anti-SSB (43.95 ± 73.12 vs. 40.92 ± 75.75, P = 0.004; 63.93 ± 103.56 vs. 55.06 ± 120.84, P = 0.008 respectively) antibodies had higher levels of alanine aminotransferase (ALT) and aspartate transaminase (AST), whereas those with anti-P antibody (28.90 ± 25.70 vs. 50.08 ± 93.00, P = 0.014; 38.51 ± 48.19 vs. 69.95 ± 142.67, P = 0.047, respectively) had lower levels of them. Anti-dsDNA antibody (P = 0.021) was associated with pulmonary arterial hypertension (PAH). The patients with anti-Ro60 (P = 0.044), anti-P (P = 0.012) and anti-dsDNA (P = 0.013) antibodies were less likely to develop Interstitial lung disease. Anti-SmRNP antibody was correlated to lower prevalence of neuropsychiatric symptoms (P = 0.037), and patients with anti-centromere antibody (ACA) were more likely to develop serositis (P = 0.016).We identified five clusters of SLE-related autoantibodies, confirmed previously reported associations of autoantibodies, and discovered new associations.

Systemic Lupus Erythematosus and Lung Involvement: A Comprehensive Review

Systemic lupus erythematosus (SLE) is a complex autoimmune disease with multiorgan manifestations, including pleuropulmonary involvement (20-90%). The precise mechanism of pleuropulmonary involvement in SLE is not well-understood; however, systemic type 1 interferons, circulating immune complexes, and neutrophils seem to play essential roles. There are eight types of pleuropulmonary involvement: lupus pleuritis, pleural effusion, acute lupus pneumonitis, shrinking lung syndrome, interstitial lung disease, diffuse alveolar hemorrhage (DAH), pulmonary arterial hypertension, and pulmonary embolism. DAH has a high mortality rate (68-75%). The diagnostic tools for pleuropulmonary involvement in SLE include chest X-ray (CXR), computed tomography (CT), pulmonary function tests (PFT), bronchoalveolar lavage, biopsy, technetium-99m hexamethylprophylene amine oxime perfusion scan, and (18)F-fluorodeoxyglucose positron emission tomography. An approach for detecting pleuropulmonary involvement in SLE includes high-resolution CT, CXR, and PFT. Little is known about specific therapies for pleuropulmonary involvement in SLE. However, immunosuppressive therapies such as corticosteroids and cyclophosphamide are generally used. Rituximab has also been successfully used in three of the eight pleuropulmonary involvement forms: lupus pleuritis, acute lupus pneumonitis, and shrinking lung syndrome. Pleuropulmonary manifestations are part of the clinical criteria for SLE diagnosis. However, no review article has focused on the involvement of pleuropulmonary disease in SLE. Therefore, this article summarizes the literature on the epidemiology, pathogenesis, diagnosis, and management of pleuropulmonary involvement in SLE.

Oral Manifestations of Systemic Lupus Erythematosus: A Systematic Review

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease that is characterized by clinical heterogeneity and irregularities in its course. The etiology and pathogenesis of this pathology are not well-understood, so there is difficulty in establishing a diagnosis and treatment plan with certainty. The aim of this systematic review is to present a qualitative synthesis of studies referring to the oral manifestations of systemic lupus erythematosus (SLE). This systematic review was performed following the PRISMA guideline. On this basis, a search for articles was performed in the PubMed, Web of Science, and Scopus databases on 19 November 2021 and updated on 15 February 2022. We chose articles published between 2012 and 2022 that analyzed the oral manifestations of SLE patients. The quality of all these studies was analyzed following the STROBE scale. A total of 15 articles were included in this study after selection. The selected articles were cross-sectional, case-control, and cohort studies. The most frequently associated oral manifestations with SLE were oral ulcers, hyposalivation, pigmentations, glossodynia, cleft tongue, cheilitis, arthritis, and secondary Sjögren's syndrome. However, despite the importance of the perception of these oral manifestations in the early diagnosis of SLE, there are still not enough studies about them.

High titers of antinuclear antibody and the presence of multiple autoantibodies are highly suggestive of systemic lupus erythematosus

The aim of this study is to evaluate the relationship between antinuclear antibody (ANA) titer and specificity, as well as the relationship between the number of positive-autoantibodies (AAbs) in antinuclear antibodies (ANAs) and specificity for systemic lupus erythematosus (SLE), so as to explore their significance in the diagnosis of SLE. A total of 1297 patients with ANA results was enrolled in this study, including 148 patients with SLE patients. The sensitivity, specificity, sensitive likelihood ratio and specific likelihood ratio of indicators in SLE were determined by receiver–operator characteristic (ROC) curve after measurement of ANA and ANAs by indirect immunofluorescence (IIF) and immunoblotting, respectively. ROC analysis showed that the specificity of ANA titer ≥ 1 +, ≥ 2 + and ≥ 3 + for SLE was estimated to be 81.29%, 90.69% and 96.52% respectively, with a increased titer-specific likelihood ratio (5.16, 9.29 and 19.60, respectively). The specificity of the number of positive-AAbs ≥ 1, ≥ 2 and ≥ 3 in ANAs for SLE was estimated to be 80.42%, 94.95% and 99.3% respectively, with a increased number-specific likelihood ratio (4.8, 15.26 and 72.48, respectively). The estimated sensitivity of the number of positive-AAbs ≥ 3, AnuA and anti-rRNP was higher than that of anti-Sm (p < 0.01) (50.68%, 41.89% and 31.76% vs. 16.89%, respectively), while there was no significant difference in their specificity (99.3%, 99.74% and 99.56% vs. 99.74%, respectively) (p > 0.05). High titers of ANA and the presence of multiple AAbs in ANAs are highly specific for SLE and highly suggestive of SLE. The likelihood of SLE can be assessed by ANA titer and the number of positive-AAbs in ANAs.

The role of anti-ribosomal P autoantibodies in the prediction of neuropsychiatric damage in systemic lupus erythematosus based on CSTAR cohort (XIV)

OBJECTIVES

To identify the predictive value of anti-ribosomal P protein (anti-RibP) antibodies on the accrual of neuropsychiatric damage in systemic lupus erythematosus (SLE) patients in a large cohort in the Chinese SLE Treatment and Research group (CSTAR) database.

METHODS

This single-center prospective study was conducted based on data from the CSTAR registry. At baseline, we collected demographic characteristics, autoantibody profiles, clinical manifestations, disease activity status, and organ damage. Follow-up data were collected by reviewing clinical records and telephone interviews. Anti-RibP antibodies were identified by immunoblot containing all three native RibP (P0, P1, P2) antigenic proteins.

RESULTS

Of 2395 SLE patients with complete follow-up data, 659 (27.5%) were anti-RibP antibody positive. At baseline, positive anti-RibP antibodies were associated with a higher proportion of neurological involvement (𝑃 < 0.05). During follow-up, patients with positive anti-RibP antibodies were more likely to accumulate neuropsychiatric damage (adjusted HR = 3.8, 95% CI 2.7-57), p < 0.001). What is more, the cumulative probability of new-onset neurological involvement increased gradually in anti-RibP antibody-positive patients.

CONCLUSION

Anti-RibP antibodies can provide information about not only organ involvement at baseline, but also neuropsychiatric damage accrual and new-onset neurological involvement during follow-up. We suggested that anti-RibP antibody detection should be done in the newly diagnosed SLE patients to predict organ involvement and even the accumulation of neuropsychiatric damage.

KEY POINTS

• Positive anti-RibP antibodies were associated with baseline neurological involvement. • Baseline positive anti-RibP antibodies can predict the neuropsychiatric damage accrual and new-onset neurological involvement.

Analyses of the clinical and immunological characteristics of patients with lupus erythematosus

BACKGROUND

Lupus erythematosus (LE) is a broad-spectrum, heterogeneous disease. At one end of the spectrum is the cutaneous LE (CLE) without systemic involvement, and at the other end is the systemic LE (SLE) with multisystem involvement. Analyses of clinical and immunological indicators and pathological examinations are helpful for early diagnosis, differential diagnosis, and prognosis of LE.

AIM AND OBJECTIVES

We described the clinical and laboratory characteristics of patients with LE and assessed the diagnostic value of immunohistochemical detection of C3d, C4d, IgG, IgG4, and CD123 in skin lesions of LE.

MATERIALS AND METHODS

Clinical and laboratory data of 62 patients with LE were collected. The expression levels of C3d, C4d, IgG, IgG4, and CD123 in skin lesions of LE were detected by immunohistochemistry (IHC).

RESULTS

Clinical manifestations such as hematological involvement, C3, C4, ESR, hematuresis, proteinuria, anti-Sm, anti-ribosomal P-protein, anti-U1-RNP, anti-histone, and anti-nucleosome antibodies are helpful for classificatory diagnosis of LE. The positive rate of C3d and/or C4d along the basement membrane zone in LE skin lesions by IHC was 74.6%, which was higher than that by direct immunofluorescence (47.5%) (P = 0.002). The expression of CD123 protein and the number of CD123+ plasmacytoid dendritic cells (PDCs) in skin lesions of patients with LE were higher than those of dermatomyositis (DM), while the distributed form of CD123 + PDCs in the dermis was different between LE and DM.

CONCLUSIONS

The diagnosis of CLE and SLE requires a combination of clinical manifestations, laboratory indicators, and pathological examination. Immunohistochemical detection of C3d, C4d, and CD123 in skin lesions is important for the classificatory diagnosis of LE.

Comparison study of bead-based and line-blot multiplex ANA immunoassays in the diagnosis of systemic autoimmune rheumatic diseases

OBJECTIVES

Detection of antinuclear antibodies (ANA) by immunofluorescence assay (IFA) is increasingly substituted by multiplex bead-based immunoassay (MBA) and line-blot immunoassay (LIA). This study is to compare the diagnostic performance of MBA and LIA ANA assays on clinically characterized patient samples.

METHODS

A total of 728 serum samples from 385 patients with systemic autoimmune rheumatic diseases (SARD), 204 patients with non-SARD diseases, and 139 apparently healthy subjects were tested with the BioPlex 2200 ANA Screen and EuroLine ANA Profile 3 as the representative MBA and LIA technologies and HEp-2 ANA IFA. Clinical data were collected independent of laboratory analysis and later related to the ANA test results. The clinical diagnostic performances were analyzed using Analyse-it software.

RESULTS

The MBA demonstrated higher area under curve (AUC) compared to LIA (0.814 vs 0.761, p = 0.002) and HEp-2 IFA (0.814 vs 0.771, p = 0.008). The MBA and LIA ANA methods showed higher specificity (83.8% and 77.0% vs 67.6%, p < 0.001 and p = 0.005) but lower sensitivity (79.0% and 75.3% vs 86.5%, p < 0.001) compared to HEp-2 IFA. The MBA and LIA ANA revealed substantial to excellent agreements on specific antinuclear antibodies except anti-dsDNA, with the total agreement from 92.3 to 99.9% and Cohen's kappa from 0.71 to 0.98. The MBA demonstrated significantly higher sensitivity (58.1% vs 19.8%, p < 0.001) and comparable specificity (95.9% vs 97.5%, p = 0.221) on anti-dsDNA assay for the diagnosis of SLE compared to LIA.

CONCLUSIONS

The MBA and LIA ANA assays have higher specificity but lower sensitivity compared to HEp-2 IFA. There are good agreements between MBA and LIA ANA for the specific antinuclear antibodies except for anti-dsDNA. The MBA ANA demonstrated better assay performance compared to LIA as the MBA possesses higher sensitivity and specificity in the diagnosis of SARD. Key Points • The multiplex bead-based immunoassay (MBA) ANA outperformed line-blot immunoassay (LIA) and traditional HEp-2 IFA. • There are good agreements between the MBA BioPlex 2200 ANA Screen and LIA EuroLine ANA Profile 3 for the most of specific antinuclear antibodies except anti-dsDNA. • Additional anti-dsDNA testing is suggested when EuroLine ANA Profile 3 is used for the aid of SLE diagnosis and management. • The positive predictive value of both multiplex ANA assays can be substantially increased without significantly affecting negative predictive value by using at least two specific antinuclear antibodies for reporting a positive ANA result.

Long-term Outcomes of Patients with Systemic Lupus Erythematosus: A Multicenter Cohort Study from CSTAR Registry

OBJECTIVE

To study the long-term outcomes, in the context of both mortality and organ damage in patients with systemic lupus erythematosus (SLE) in the Chinese SLE Treatment and Research group (CSTAR) registry cohort.

METHODS

Patients were enrolled from April 2009 to February 2010 and they were followed up. The demographic data, clinical manifestations, labs test results and imaging examinations, disease activity (SLEDAI-2K), damage scores (SLLIC/Damage Index [SDI]), and medications were collected. Data were censored at either the last clinic visit or telephonic interview. Survival rate was analyzed by Kaplan-Meier (KM) method. COX proportional hazard model was adopted to perform the analysis of predicting factors for mortality and organ damage. Logistic regression analysis was employed to discuss the relationship among mortality, organ damage, and flare.

RESULTS

A total of 2104 patients were recruited at baseline and 1494 patients were followed up. The cumulative 1-year, 3-year, and 5-year survival rates were 98.3%, 96.9%, and 95.7%, respectively. Seventy-eight patients died during follow-up, and the main causes of death were infection (34.6%), active disease (26.9%), cardiovascular and cerebrovascular events (5.13%), and malignancy (5.13%). At entry, 247 patients presented with irreversible organ damage and it increased to 398 patients at the endpoint. The major accumulated organ damages were kidney (25.9%), musculoskeletal disease (20.2%), neuropsychiatric disease (12.2%), and pulmonary damage (10.9%). Cox regression analysis further showed that male, late disease onset, delayed diagnosis (diagnosis from disease onset >1 year), baseline organ damage, and specific organ involvements predicted for higher mortality. In addition, early disease onset was a protecting factor for organ damage, and anti-SSA was an independent predicting factor for new organ damage. Logistic regression analysis showed that flare predicted for more organ damage.

CONCLUSION

The 5-year survival rate of Chinese SLE patients has improved and is comparable to Caucasians SLE patients. Disease flare impact on prognosis is the increasing risk of damage development. Early diagnosis, prevention for flare and damage to maintain remission, may improve outcome.

A nomogram to predict the risk of lupus enteritis in systemic lupus erythematosus patients with gastroinctestinal involvement

BACKGROUND

Lupus enteritis (LE), a main cause of acute abdominal pain in systemic lupus erythematosus (SLE) patients, is a serious and potentially fatal complication. This study aimed to identify clinical serological indicators to establish a nomogram to assess LE in SLE patients with gastrointestinal manifestations.

METHODS

The clinical and laboratory data of SLE patients with gastrointestinal manifestations that were hospitalized in the West China Hospital from January 2010 to January 2020 were retrospectively analyzed. The least absolute shrinkage and selection operator logistic regression model was used to select potentially relevant features. Subsequently, a nomogram was developed using multivariable logistic analysis. The performance of the nomogram was evaluated using a receiver operating characteristic curve, a calibration curve, and decision curve analysis (DCA).

FINDINGS

We included a total of 8,505 SLE patients, of which 251 had experienced gastrointestinal manifestations. The patients were randomly divided into training (n = 176) and validation (n = 75) groups. The LRA (LE Risk Assessment) model consisted of 11 significantly associated variables, which included complement 4, antineutrophil cytoplasmic antibody, albumin, anion gap, age, d-dimer, platelet, serum chlorine, anti-Sjögren's-syndrome-related antigen A, anti-ribosomal P protein, and anti-ribonucleoprotein. In the training and validation cohorts, the areas under the curve were 0.919 (95% confidence interval [CI]: 0.876-0.962) and 0.870 (95% CI: 0.775-0.964), respectively. The nomogram demonstrated excellent performance in the calibration curve and DCA.

INTERPRETATION

The LRA model exhibits good predictive ability in assessing LE risk in SLE patients with gastrointestinal manifestations.

Chinese SLE Treatment and Research Group Registry (CSTAR) XIII: prevalence and risk factors for chronic scarring alopecia in patients with systemic lupus erythematosus

Background

Scarring alopecia in systemic lupus erythematosus (SLE) patients caused reduced life quality and prolonged disease course. This case-control study aims to survey the prevalence of scarring alopecia during the disease course of SLE and evaluate the risk factors for scarring alopecia in Chinese SLE patients.

Methods

SLE patients in Chinese SLE treatment and Research group (CSTAR) were recruited. Scarring alopecia was defined according to SLICC/ACR-DI which was collected during follow-up visits or via self-reported questionnaires. We collected demographic characteristics, common comorbidities, autoantibody profiles, disease activity status, major organ involvements, and treatment strategies of these patients at registry. Univariate and multivariate logistic regression analyses were used to investigate the risk factors for scarring alopecia.

Results

We recruited 4792 SLE patients, and 374 (7.80%) patients had scarring alopecia. Mucocutaneous lesions (OR 2.062, p < 0.001), high SLICC/ACR-DI (OR 1.409, p < 0.001), and positive anti-Sm (OR 1.374, p = 0.029) were risk factors for scarring alopecia, while renal (OR 0.714, p = 0.028) and cardio-respiratory involvements (OR 0.347, p = 0.044), and immunosuppressant treatment (OR 0.675, p < 0.001) were significantly negative associated with it.

Conclusions

The prevalence of scarring alopecia in SLE patients is 7.80%. Active treatment strategies should be adopted to prevent scarring alopecia occurring.

Causes and Factors Associated with Frequent Hospitalization in Chinese Patients with Systemic Lupus Erythematosus: An Ambispective Cohort Study

Background

Hospitalizations in patients with systemic lupus erythematosus (SLE) have been reported from different regions in the world. This study aimed to evaluate the annual hospitalization rate, causes of hospitalization, and potential factors associated with frequency of hospitalization in Chinese patients.

Material/Methods

We performed an ambispective cohort study for hospitalized patients with SLE in a Chinese single center. Data on demographics, organ involvements, laboratory abnormities, clinical treatments, causes of hospitalization, and survival outcomes were recorded at the time of SLE diagnosis and during a follow-up period. Poisson regression models were created to identify the potential factors associated with frequency of hospitalization.

Results

Of 526 patients with SLE, 242 patients (46%) had 1 or more admissions amounting to a total of 449 times during a median follow-up period of 4.73 years. The annual hospitalization rate was 18% and death occurred in 2.5% of total admissions. SLE flare, infection and pregnancy-related morbidity were the most common causes of hospitalization. Besides, the multivariate Poisson regression analysis revealed that decreased albumin, decreased renal function, and high disease damage were the risk factors for more frequency of hospitalization, whereas positive anti-SSA antibody and use of hydroxychloroquine were protective factors.

Conclusions

Nearly half of patients (46%) with SLE experience 1 or more hospitalizations, mainly due to SLE flare, infection, and pregnancy-related morbidity. Lupus patients with decreased albumin, decreased renal function, and high disease damage are more susceptible to have frequent hospitalization.

Antiphospholipid antibodies in patients with lupus nephritis: clinical correlations and associations with long-term outcomes

Whether the presence or absence of antiphospholipid antibodies (aPL) in patients with lupus nephritis (LN) is associated with differences in clinical outcomes remains unclear. We reviewed LN patients at a single centre during 2000-2017, and compared the clinical features and long-term outcomes between patients who were seropositive or seronegative for aPL. aPL was detected in 53/149 (35.6%) patients with biopsy-proven LN, and anticardiolipin IgM, anticardiolipin IgG, anti-β2 glycoprotein I and lupus anticoagulant was detected in 18.8%, 18.1%, 10.7% and 8.1%, respectively. Follow-up was 155.8 ± 61.0 months, and was similar between aPL-seropositive and -seronegative patients. aPL seropositivity persisted in 94.3% of patients during remission. aPL-seropositive patients showed inferior patient survival (91% and 85% at 10 and 15 years, respectively, compared to 99% and 95% in aPL-seronegative patients; p = 0.043). Nine (6.0%) patients died during follow-up, including six aPL-seropositive (four thrombotic events and two bleeding complications related to anticoagulation) and three aPL-seronegative patients. aPL seropositivity was associated with more rapid decline in estimated glomerular filtration rate (-1.44 mL/min/year compared to -0.38 mL/min/year in aPL-seronegative patients; p = 0.027) and inferior long-term renal survival (82% and 74% at 10 and 15 years, respectively, compared to 91% and 87% in aPL-seronegative patients; p = 0.034). aPL-seropositive patients also had a higher incidence of thrombotic events and miscarriage (32.1% and 13.2%, respectively, compared to 16.7% and 2.1% in the aPL-seronegative group; p = 0.030 and 0.006). We concluded that aPL seropositivity was associated with inferior long-term patient and renal survival and more frequent thrombotic events and miscarriage in LN patients.

The Predictive Value of Autoantibody Spectrum on Organ Damage in Patients With Systemic Lupus Erythematosus

OBJECTIVES

This study aims to investigate the positive detection rate and predictive value of autoantibodies, including anti-double stranded deoxyribonucleic acid (anti-dsDNA) antibodies, anti-histone antibodies (AHAs), anti-ribosomal (anti-Rib) P antibodies, anti-Smith (anti-Sm) antibodies, anti-U1 ribonucleoprotein (anti-U1RNP) antibodies, anti-Sjögren's syndrome type A antibodies and anti-Sjögren's syndrome type B antibodies, on organ damage in patients with systemic lupus erythematous (SLE).

PATIENTS AND METHODS

A total of 225 patients with SLE (37 males, 188 females; mean age 37.4±15.9 years; range, 7 to 80 years) were evaluated retrospectively. Statistical analysis was performed to obtain the positive detection rate of autoantibodies and to investigate the predictive value.

RESULTS

There were statistically significant differences of positive anti-dsDNA antibodies in renal damage, photosensitization, hematological abnormalities and serositis (p<0.05) and a statistically significant difference of positive AHAs in photosensitization (p<0.05). There was statistically significant difference of positive anti-U1RNP antibodies in renal damage (p<0.05). There were also statistically significant differences of positive anti-Smith antibodies in renal damage, arthritis, photosensitization, oral ulcers, hematological abnormalities and serositis (p<0.05) and of positive anti-Rib antibodies in renal damage, arthritis, photosensitization, malar rash, hematological abnormalities and serositis (p<0.05). However, there were no statistically significant differences of positive anti-Sjögren's syndrome type B antibodies and anti-Sjögren's syndrome type A antibodies in renal damage, arthritis, malar rash, neuropsychiatric disorders, hematological abnormalities and serositis (p>0.05).

CONCLUSION

Autoantibody spectrum is an important serological basis for SLE diagnosis. There are differences in the autoantibodies distribution of SLE patients with different organ damage, suggesting a certain clinical value for prediction of organ damage in SLE.

Risk factors for progression of carotid intima-media thickness in patients with systemic lupus erythematosus: protocol for an observational cohort study in China

INTRODUCTION

Accelerated atherosclerosis is a major complication of systemic lupus erythematosus (SLE), and it leads to increased cardiovascular morbidity and mortality in patients with SLE. This study aimed to investigate the natural progression of carotid intima-media thickness (CIMT), and to examine the risk factors for progression of CIMT and atherosclerotic plaques based on a Chinese SLE cohort.

METHODS AND ANALYSIS

Participants were continuously enrolled as outpatients of the Department of Rheumatology in Peking Union Medical College Hospital (PUMCH) from October 2013 to December 2016. Inclusion criteria were as follows: (1) age ≥18 years, (2) fulfilment of clinical classification criteria of SLE and (3) provision of signed written informed consent. Patients with clinically overt coronary artery disease, a history of cardiovascular disease (previous stroke, heart failure, myocardial infarction, angina or symptomatic peripheral artery disease) and malignancy, and pregnant/lactating women were excluded. The primary outcome is progression of CIMT from baseline. A total of 440 patients with SLE will be enrolled. Participants will receive follow-up surveys ~5 years after their baseline visit. A standard structural survey form, including demographic data, medical history, clinical and laboratory assessments and CIMT measurement, is planned for data collection at baseline and follow-up. The risk prediction model for progression of CIMT will be created by using a mixed effect model.

ETHICS AND DISSEMINATION

The study protocol was approved by the institutional review board of PUMCH (S-599). Informed consent was obtained from all participants according to the Declaration of Helsinki on Biomedical Research Involving Human Studies. All data will be managed confidentially according to guidelines and legislation. Dissemination will include publication of scientific papers and/or presentations of the study findings at international conferences.

Malar rash is a predictor of subclinical airway inflammation in patients with systemic lupus erythematosus: a pilot study

BACKGROUND

Systemic lupus erythematosus (SLE) is a chronic, auto-immune, multi-organ disease that can affect both the skin and the lungs. Malar rash is a common skin manifestation of SLE and is linked to SLE disease activity, whereas lung involvement is a generally negative prognostic factor for these patients. However, a sensitive and non-invasive screening tool for potential lung involvement in SLE patients is still not available.

METHODS

This study aimed to investigate the relationship between malar rash and airway inflammation in adult SLE patients who were not known to have any lung involvement (clinical or radiologic). The study comprised of the measurement of the concentration of NO in exhaled breath or fraction of exhaled nitric oxide (FeNO) and levels were compared between those with and without malar rash. This tool is considered as a sensitive and non-invasive method that is routinely used in patients with asthma or other respiratory diseases to identify airway inflammation.

RESULTS

A total of 125 patients (100 females, 25 males) were enrolled during the study period from January 2011 to December 2014. Patients with malar rash (N = 35) had a significant decrease in serum levels of C4 (p < 0.05) compared to patients without malar rash (N = 90). The mean levels of FeNO in overall patients were 36.44 ± 8.87 ppb. A statistically significant difference in FeNO₅₀ values between patients with malar rash (43.46 ± 6.72 ppb) and without (29.43 ± 3.64 ppb) was found (p < 0.001). FeNO₅₀ values were inversely correlated only with serum C4 (p < 0.01). However, no correlation between FeNO₅₀ values and SLE clinical disease activity scores was found.

CONCLUSIONS

The presence of a malar rash may predict sub-clinical airway inflammation in SLE patients. Further prospective studies are needed to confirm the usefulness of FeNO measurements in monitoring SLE-associated airway inflammation.

Clinical Outcomes and Clinico-pathological Correlations in Lupus Nephritis with Kidney Biopsy Showing Thrombotic Microangiopathy

Objective.

Renal thrombotic microangiopathy (TMA) is an uncommon pathological finding in lupus nephritis (LN), and its clinical significance remains to be defined.

Methods.

Twenty-four patients with lupus nephritis (LN) and renal TMA were selected from a retrospective review of 677 biopsy-proven LN patients, and compared with 48 LN controls without TMA (1:2 ratio) matched according to demographics and treatments.

Results.

Renal TMA was noted in 3.5% of kidney biopsies of LN. TMA was associated with a higher prevalence of anti-Ro (45.8% vs 18.8%; p = 0.016), higher Systemic Lupus Erythematosus Disease Activity Index scores (21.4 ± 8.5 vs 10.8 ± 2.3; p < 0.001), lower estimated glomerular filtration rate (eGFR; 16.8 ± 11.7 ml/min vs 77.8 ± 28.6 ml/min; p < 0.001), and a higher percentage of patients who required dialysis (37.5% vs 2.1%; p < 0.001) at the time of kidney biopsy. Activity and chronicity indices [median (range)] were higher in the TMA group [11 (2–19) and 3 (1–8), respectively, compared with 7 (0–15) and 1 (0–3) in controls; p = 0.004 and p < 0.001; respectively]. Patients with TMA showed inferior 5-year renal survival and higher incidence of chronic kidney disease at last followup (70% and 66.6%, respectively, compared with 95% and 29.2% in controls; p = 0.023 and 0.002, respectively). The TMA group also showed lower median eGFR compared with controls [50.1 (IQR 7–132) ml/min vs 85.0 (IQR 12–147) ml/min; p = 0.003]. Five-year patient survival rate was similar between the 2 groups (87% and 98% in TMA and control group, respectively; p = 0.127).

Conclusion.

TMA in kidney biopsy was associated with more severe clinical and histological activity, and significantly inferior longterm renal outcome in LN.

T-bet+CD11c+ B cells are critical for antichromatin immunoglobulin G production in the development of lupus

Background

A hallmark of systemic lupus erythematosus is high titers of circulating autoantibodies. Recently, a novel CD11c⁺ B-cell subset has been identified that is critical for the development of autoimmunity. However, the role of CD11c⁺ B cells in the development of lupus is unclear. Chronic graft-versus-host disease (cGVHD) is a lupus-like syndrome with high autoantibody production. The purpose of this study was to explore the role of CD11c⁺ B cells in the pathogenesis of lupus in cGVHD mice.

Methods

cGVHD was induced by an intraperitoneal injection of 5 × 10⁷ Bm12 splenocytes into B6 mice. Flow cytometry was used to analyze mice splenocytes and human samples. Magnetic beads were used to isolate mice B cells. Gene expression was determined by real-time quantitative polymerase chain reaction (RT-qPCR). Enzyme-linked immunosorbent assay (ELISA) was used to detect antibodies in serum and supernatants.

Results

The percentage and absolute number of CD11c⁺ B cells was increased in cGVHD-induced lupus, with elevated levels of antichromatin immunoglobulin (Ig)G and IgG2a in sera. CD11c⁺ plasma cells from cGVHD mice produced large amounts of antichromatin IgG2a upon stimulation. Depletion of CD11c⁺ B cells reduced antichromatin IgG and IgG2a production. T-bet was upregulated in CD11c⁺ B cells. Knockout of T-bet in B cells alleviated cGVHD-induced lupus. Importantly, the percentage of T-bet⁺CD11c⁺ B cells increased in lupus patients and positively correlated with serum antichromatin levels.

Conclusion

T-bet⁺CD11c⁺ B cells promoted high antichromatin IgG production in the lupus-like disease model cGVHD. In lupus patients, the percentage of T-bet⁺CD11c⁺ B cells was elevated and positively correlated with antichromatin antibodies. The findings provide potential therapeutic insight into lupus disease treatment.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-017-1438-2) contains supplementary material, which is available to authorized users.

Pathogenesis of cutaneous lupus erythema associated with and without systemic lupus erythema

Cutaneous lupus erythematosus (CLE) can be an individual disease only involving skin, or presents as part of the manifestations of SLE. A small proportion of CLE may progress into SLE, however, the underlying pathogenic mediators remain elusive. By only including researches that clearly described if the subtypes of CLE presented by enrolled subjects was associated with or without SLE, we provided an overview of antibodies, inflammatory cells and inflammatory molecular mediators identified in blood and skin that were possibly involved in lupus skin damages. IgG autoantibodies are crucial for the development of CLE associated with SLE, but the circulating inflammatory cells and molecular mediators require further studies to provide definitive proof for their association with skin damages. Discoid lupus erythematosus (DLE) is the most common subtype of CLE. For DLE without associated with SLE (CDLE), it is lack of evidences if autoantibodies and circulating inflammatory cells are involved in the pathogenesis or not, but is clear that the cutaneous inflammatory infiltrates are dominated by Th1, but not Th17 cells in contrast to the various complex profile in SLE. As the major target cells in skin, keratinocytes may participate the pathophysiological process by increase cell apoptosis and the production of proinflammatory cytokines in SLE and CDLE. Insights into the similarities and differences of the pathogenesis of CLE and CLE associated with SLE will also improve our therapeutic strategies for CLE that is currently adopted from SLE, and prevent the progression of CLE to SLE by providing interventions within an appropriate window of disease development.

Chinese SLE Treatment and Research Group (CSTAR) registry:VIII. Influence of socioeconomic and geographical variables on disease phenotype and activity in Chinese patients with SLE

AIM

The aim of this study was to estimate the influence of socioeconomic and geographical variables on disease phenotype and activity of systemic lupus erythematosus (SLE) in a Chinese population.

METHODS

Data on 904 therapy-naïve SLE patients from the Chinese SLE Treatment and Research Group (CSTAR), which is a nation-wide database of SLE patients, were used to evaluate the influence of socioeconomic status (SES) and geographical regions on disease phenotypes. The influence of regional climate and economic variables (i.e., data from the database of the Chinese Statistical Yearly Annals) on disease activity and nephropathy was further analyzed in a multivariate analysis to identify some of the environmental factors contributing to SLE.

RESULTS

Phenotype differences in SLE were found between patients with different SES. In the multivariate regression analysis that considered regional economic and climate factors, after adjusting for age, gender and disease duration, lower educational levels (β: -0.122, P = 0.001), lower availability of medical technical personnel (MTP) per 1000 people (β: -0.192, P < 0.001), higher annual duration of sunshine (β: 0.178, P = 0.010) and residence in southern China (β: 0.165, P = 0.001) were significantly associated with higher disease activity scores. Living in southern China (odds ratio [OR]: 1.907, P = 0.002) seemed to be a significant risk factor for nephropathy. A high number of MTP per 1000 people (OR: 0.951, P = 0.014) and relatively high temperatures were determined to be protective factors for nephropathy (OR: 0.946, P = 0.011).

CONCLUSIONS

The phenotype pattern and disease activity varied between SLE patients by SES and other regional variables, such as educational level, availability of medical technical personnel, annual sunshine duration and regional temperature.

CCL2 deficient mesenchymal stem cells fail to establish long-lasting contact with T cells and no longer ameliorate lupus symptoms

Systemic lupus erythematosus (SLE) is a multi-organ autoimmune disease characterized by autoantibody production. Mesenchymal stem cells (MSCs) ameliorate SLE symptoms by targeting T cells, whereas the mechanisms of their efficacy remain incompletely understood. In this study, we show that transfer of human MSCs increased MRL.Fas^lpr mouse survival, decreased T cell infiltration in the kidneys, and reduced T cell cytokine expression. In vitro, allogeneic mouse MSCs inhibited MRL.Fas^lpr T cell proliferation and cytokine production. Time-lapse imaging revealed that MSCs recruited MRL.Fas^lpr T cells establishing long-lasting cellular contacts by enhancing T cell VCAM-1 expression in a CCL2-dependent manner. In contrast, CCL2 deficient MSCs did not induce T cell migration and VCAM-1 expression, resulting in insufficient cell-cell contact. Consequently, CCL2 deficient MSCs did not inhibit IFN-γ production by T cells and upon transfer no longer prolonged survival of MRL.Fas^lpr mice. Taken together, our imaging study demonstrates that CCL2 enables the prolonged MSC-T cell interactions needed for sufficient suppression of autoreactive T cells and helps to understand how MSCs ameliorate symptoms in lupus-prone MRL.Fas^lpr mice.

Cutaneous characteristics and association with antinuclear antibodies in 402 patients with different subtypes of lupus erythematosus

BACKGROUND

Lupus erythematosus (LE) is an autoimmune disease characterized by a heterogeneous spectrum of skin manifestations and organ affection, and is frequently associated with serum autoantibodies, which mostly remain positive through the course of the disease. The classification of LE is still a controversial topic.

OBJECTIVES

To examine the prevalence and long-term course of autoantibodies in patients with cutaneous LE (CLE) and/or systemic LE (SLE) treated in the outpatient clinic for connective tissue diseases of the department of Dermatology in Bochum, Germany.

METHODS

Four hundred and two patients with LE were evaluated for antinuclear antibodies at a whole of 1572 time points. The prevalence as well as the long-term positivity of antinuclear antibodies and their correlation with the various subtypes of disease was examined.

RESULTS

Antinuclear antibody (ANA) testing and anti-ds-DNA antibodies were not only more prevalent in SLE patients (as expected from the ACR criteria for diagnosis of SLE, P < 0.0001), but also have had a more consistent course in the long-term evaluation (P = 0.0001 and P = 0.0111 respectively). Subacute cutaneous LE (SCLE) was associated with ANA (P = 0.0075), anti-Ro (P < 0.0001) and anti-La (P < 0.0001) antibodies, showing also higher consistency rates for these antibodies than discoid LE (DLE, P = 0.049, P = 0.004, P = 0.0004). Our data from 100 patients with LE tumidus (LET) support its perception as a distinct subtype of LE, not correlating with systemic disease or antinuclear antibodies (P < 0.0001). Anti-U1-ribonucleoprotein antibodies correlated with CLE in SLE patients (P = 0.0237), whereas non-LE-specific antinuclear antibodies were a rare, inconsistent autoimmune epiphenomenon in patients with SLE.

CONCLUSION

Long-term analysis of antinuclear antibodies has shown significant differences in various clinical subtypes of LE, confirming the actual classification of the disease. A serial evaluation of antinuclear antibodies may support the classification of disease in LE patients with overlapping clinical features.

Baseline Characteristics and Risk Factors of Pulmonary Arterial Hypertension in Systemic Lupus Erythematosus Patients

Peking Union Medical College Hospital (PUMCH) has started a single-center right heart catheterization (RHC)-based pulmonary arterial hypertension (PAH) study in systemic lupus erythematosus (SLE) since 2006. The baseline characteristics of these patients were described and the risk factor for PAH in lupus was identified.The demographic, clinical, laboratory, and treatment characteristics of SLE patients with PAH when they were registered were collected as the baseline data. A case-control study was conducted by taking the admitted SLE-non-PAH patients adjusted for age and gender in a 4:1 ratio during the same period as the controls. The associated variables were examined by binary multivariate logistic regression analysis to identify possible risk factors. A total of 111 RHC-confirmed SLE-PAH patients were enrolled, with the onset age of 34.6 ± 8.6 years old and the average SLE duration of 5 years. RHC revealed mPAP as 46.4 ± 11.4 mm Hg, CI as 2.7 ± 0.8 L/min × m, and PVR as 10.5 ± 4.8 WU. 46% of patients were WHO Fc I-II. All patients were treated with immunosuppressive agents and 65% patients had PAH-targeted therapy. The case-control study had confirmed 2 independent risk factors previously published: pericardial effusion (OR = 21.290, P < 0.001) and anti-RNP antibody (OR = 12.399, P < 0.001). Meanwhile, 6 independent variables were discovered: baseline SLE duration (OR = 1.118, P = 0.007), interstitial lung disease (OR = 17.027, P < 0.001=, without acute rash (OR = 3.258, P = 0.019), anti-SSA antibody (OR = 4.836, P = 0.004), SLEDAI≤9 (OR = 26.426, P < 0.001), ESR≤20 mm/h (OR = 12.068, P < 0.001), and uric acid > 357 μmol/L (OR = 9.666, P < 0.001) to be associated with PAH in SLE patients.The PUMCH study has shown that SLE patients complicated with PAH are usually earlier diagnosed and have less disease severity than patients without PAH. The immunosuppressive therapy rate and the PAH target therapy rate were high, which is consistent with reports from Western countries. This study has confirmed that pericardial effusion and positive anti-RNP antibody are risk factors for SLE-associated PAH. Long SLE disease duration, the presence of interstitial lung disease, without acute skin rash, positive anti-SSA antibody, low SLEDAI and ESR, and high uric acid levels are also associated with PAH in SLE patients.

Autoantibodies in SLE: Specificities, Isotypes and Receptors

Systemic Lupus Erythematosus (SLE) is characterized by a wide spectrum of auto-antibodies which recognize several cellular components. The production of these self-reactive antibodies fluctuates during the course of the disease and the involvement of different antibody-secreting cell populations are considered highly relevant for the disease pathogenesis. These cells are developed and stimulated through different ways leading to the secretion of a variety of isotypes, affinities and idiotypes. Each of them has a particular mechanism of action binding to a specific antigen and recognized by distinct receptors. The effector responses triggered lead to a chronic tissue inflammation. DsDNA autoantibodies are the most studied as well as the first in being characterized for its pathogenic role in Lupus nephritis. However, others are of growing interest since they have been associated with other organ-specific damage, such as anti-NMDAR antibodies in neuropsychiatric clinical manifestations or anti-β2GP1 antibodies in vascular symptomatology. In this review, we describe the different auto-antibodies reported to be involved in SLE. How autoantibody isotypes and affinity-binding to their antigen might result in different pathogenic responses is also discussed.

Anti-Endothelin Receptor Type A Autoantibodies in Systemic Lupus Erythematosus-Associated Pulmonary Arterial Hypertension

OBJECTIVE

To investigate the role of autoantibodies against endothelin 1 receptor type A (ETRA) in patients with systemic lupus erythematosus (SLE)-associated pulmonary arterial hypertension (PAH) and to examine the possibility that the pathogenesis of this disease is mediated by these autoantibodies.

METHODS

ETRA autoantibodies in serum from patients with SLE-associated PAH and serum from controls (SLE patients without PAH) were detected via a human ETRA epitope peptide-based enzyme-linked immunosorbent assay. An exploratory cohort of patients with SLE-associated PAH (n = 76) and an independent validation cohort of patients with SLE-associated PAH confirmed by right-sided heart catheterization (RHC) (n = 82) were enrolled. The clinical relevance of ETRA autoantibodies in SLE-associated PAH was analyzed. The proliferation of vascular smooth muscle cells (SMCs) and the permeability of endothelial cells (ECs) were assessed in vitro in cells stimulated with polyclonal ETRA IgG autoantibodies. Expression of PAH-related markers, i.e., serotonin transporter, platelet-derived growth factor receptor β, vascular endothelial growth factor A, and platelet-derived growth factor B was measured by quantitative polymerase chain reaction. In addition, a suboptimal dose of monocrotaline was used to induce PAH in rats, and the effect of ETRA autoantibodies in vivo was determined using a right ventricular hypertrophy index, pulmonary angiography, and laboratory parameters.

RESULTS

ETRA autoantibodies occurred more frequently in SLE-associated PAH (41.5%) than in controls (17.1%). There was a significant correlation between ETRA autoantibody titers and pulmonary artery systolic pressure measured by echocardiography (r = 0.2978, P = 0.0038) or pulmonary artery systolic pressure measured by RHC (r = 0.2159, P = 0.0257) in SLE-associated PAH. ETRA autoantibodies could promote SMC proliferation, disrupt the endothelial barrier, and up-regulate expression of PAH-related markers, which could be blocked in the presence of an endothelin receptor antagonist. ETRA autoantibodies aggravated right ventricular hypertrophy and vascular remodeling in vivo.

CONCLUSION

We identified ETRA autoantibodies as a biomarker of mechanistic relevance in SLE. These autoantibodies may mediate PAH development in SLE.

Clinical associations of anti-Smith antibodies in PROFILE: a multi-ethnic lupus cohort

The aim of this study was to determine the association of anti-Sm antibodies with clinical manifestations, comorbidities, and disease damage in a large multi-ethnic SLE cohort. SLE patients (per American College of Rheumatology criteria), age ≥16 years, disease duration ≤10 years at enrollment, and defined ethnicity (African American, Hispanic or Caucasian), from a longitudinal US cohort were studied. Socioeconomic-demographic features, cumulative clinical manifestations, comorbidities, and disease damage (as per the Systemic Lupus International Collaborating Clinics Damage Index [SDI]) were determined. The association of anti-Sm antibodies with clinical features was examined using multivariable logistic regression analyses adjusting for age, gender, ethnicity, disease duration, level of education, health insurance, and smoking. A total of 2322 SLE patients were studied. The mean (standard deviation, SD) age at diagnosis was 34.4 (12.8) years and the mean (SD) disease duration was 9.0 (7.9) years; 2127 (91.6%) were women. Anti-Sm antibodies were present in 579 (24.9%) patients. In the multivariable analysis, anti-Sm antibodies were significantly associated with serositis, renal involvement, psychosis, vasculitis, Raynaud's phenomenon, hemolytic anemia, leukopenia, lymphopenia, and arterial hypertension. No significant association was found for damage accrual. In this cohort of SLE patients, anti-Sm antibodies were associated with several clinical features including serious manifestations such as renal, neurologic, and hematologic disorders as well as vasculitis.

A new look at rheumatology in China--opportunities and challenges

In the past two decades, Chinese rheumatology has developed rapidly in terms of both clinical practice and basic research. Many rheumatology departments and divisions have been established, creating positions for more residents to join rheumatology practices. Numerous studies of rheumatic diseases have been published in recent years by Chinese rheumatologists and immunologists, supported by government funding that has dramatically increased over the past few years. These studies are focused mainly on epidemiology, mechanisms, early diagnosis and interventions of rheumatic diseases. Increasing numbers of national and international scientific activities in China, including research collaborations, education programmes and conferences have greatly helped the development of rheumatology. In this APLAR series article, the major, high-impact studies and latest developments in Chinese rheumatology are reviewed.