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Introducción: Los autoanticuerpos anti-C1q han sido propuestos como un marcador útil en el lupus eritematoso sistémico por su asociación con la nefritis lúpica. Objetivo: Determinar la prevalencia de anti-C1q en pacientes con lupus eritematoso sistémico y otras enfermedades reumáticas para la evaluar la asociación con la nefropatía lúpica. Métodos: Se incluyeron 179 pacientes con lupus eritematoso sistémico y 82 con otras enfermedades reumáticas. La nefritis lúpica fue diagnosticada en 70 (39 por ciento) de los pacientes con lupus eritematoso sistémico. Los anticuerpos anti-C1q IgG se determinaron por ELISA. Las asociaciones se evaluaron por análisis de regresión logística. Resultados: La prevalencia de anti-C1q fue de 37 poe ciento (66/179) en los pacientes con lupus eritematoso sistémico y de 9 por ciento (7/82) en controles (OR = 6,3; IC 95 por ciento 2,8-14,1; p < 0,001). El anti-C1q fue asociado con proteinuria (OR = 2,6; IC 95 por ciento 1,2-6,0; p < 0,022); eritrosedimentación elevada (OR = 3,2; IC 95 por ciento 1,5-6,7; p < 0,003) y anti-DNAdc (OR = 3,9; IC 95 por ciento 1,7-9,1; p < 0,002). En el modelo de regresión logística ajustado para demografía y anti-DNAdc, aunque la OR del anti-C1q para la nefritis fue 2 veces más alta que en ausencia del anti-C1q, solo se aproximó a la significación estadística. La positividad simultánea de anti-C1q y anti-DNAdc estuvo asociada a la nefritis lúpica (OR = 4,3; IC 95 por ciento 1,9-9,5; p < 0,001). Conclusiones: El anti-C1q se presentó con mayor frecuencia en pacientes con lupus eritematoso sistémico que en los controles. El anti-C1q combinado con anti-DNAdc resultó fuertemente asociado a la nefritis lúpica(AU)
Introducción: Anti-C1q autoantibodies have been proposed as useful marker in systemic lupus erythematosus due to their association with lupus nephritis. Objective: To determine the prevalence of anti-C1q in patients with systemic lupus erythematosus and other rheumatic diseases to evaluate the association with lupus nephropathy. Methods: One hundred seventy-nine patients with systemic lupus erythematosus and 82 with other rheumatic diseases were included. Lupus nephritis was diagnosed in 70 (39percent) of patients with systemic lupus erythematosus. Anti-C1q IgG antibodies were determined by ELISA. Associations were evaluated by logistic regression analysis. Results: The prevalence of anti-C1q was 37percent (66/179) in patients with systemic lupus erythematosus and 9percent (7/82) in controls (OR = 6.3; 95percent CI 2.8-14). .1; p < 0.001). Anti-C1q was associated with proteinuria (OR = 2.6; 95percent CI 1.2-6.0; p < 0.022); elevated erythrocyte sedimentation rate (OR = 3.2; 95percent CI 1.5-6.7; p < 0.003) and anti-dsDNA (OR = 3.9; 95percent CI 1.7-9.1; p < 0.002). In the logistic regression model adjusted for demographics and anti-dsDNA, although the OR of anti-C1q for nephritis was 2-fold higher than in the absence of anti-C1q, it only approached statistical significance. Simultaneous positivity of anti-C1q and anti-dsDNA was associated with lupus nephritis (OR = 4.3; 95percent CI 1.9-9.5; p < 0.001). Conclusions: Anti-C1q occurred more frequently in patients with systemic lupus erythematosus than in controls. Anti-C1q combined with anti-dsDNA was strongly associated with lupus nephritis(AU)
Subject(s)
Humans , Male , Female , Lupus Nephritis/epidemiology , Lupus Erythematosus, Systemic/epidemiologyABSTRACT
Objective:To evaluate the correlation between anti-C1q antibody and disease activity and cellular immune function in patients with systemic lupus erythematosus (SLE).Methods:The clinical data and test indexes of 134 patients with SLE and 90 healthy people who were admitted to Henan Provincial People′s Hospital from June 2017 to February 2018 were collected. The level of anti-C1q antibody was measured by enzyme-linked immunosorbent assay (ELISA), and lymphocyte subsets were measured by flow cytometry. According to the score of Systemic Lupus Erythematosus Disease Activity Index (SLEDAI)-2K, SLE patients were divided into active and inactive groups, and SLE patients were divided into LN group and non-LN group according to the presence or absence of kidney involvement. The levels of anti-C1q antibodies and lymphocyte subsets were compared among the three groups, and correlations between anti-C1q antibodies and disease activity and lymphocytes were analyzed. The predictive value of anti-C1q antibodies and anti double stranded DNA (dsDNA) antibodies for SLE disease activity was evaluated.Results:The anti-C1q antibody level, percentage of T cells and Ts cells in SLE group were higher than those in control group, while the percentage of Th cells, percentage of NK cells, T cell count, Th cell count, B cell count and NK cell count in SLE group were lower than those in control group (all P<0.05); The anti-C1q antibody level in the active group was higher than that in the inactive group, and the counts of T cells, Ts cells, Th cells, B cells and NK cells were lower than those in the inactive group (all P<0.05); The anti-C1q antibody level in LN group was higher than that in non-LN group, and the T cell count, Ts cell count, Th cell count, B cell count, NK cell count were lower than that in non-LN group, with statistically significant difference (all P<0.05). Correlation analysis showed that age, hemoglobin (HB), C3, C4, T cell count, Th cell count, B cell count and NK cell count were negatively correlated with anti-C1q antibody, while SLEDAI-2K, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR) and anti-dsDNA antibody were positively correlated with anti-C1q antibody (all P<0.05). Receiver operating characteristic (ROC) curve analysis showed that the area under the curve (AUC) of anti-C1q antibody alone in predicting SLE disease activity was 0.702, with a sensitivity of 0.547 and a specificity of 0.827. The combination of anti-C1q and anti ds-DNA antibodies resulted in an AUC of 0.761, a sensitivity of 0.756, and a specificity of 0.691. The combined detection value of the two antibodies predicting SLE disease activity was better than the single detection. Conclusions:Anti-C1q antibody is closely related to disease activity and cellular immune dysfunction, and has certain predictive value in SLE disease activity.
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ABSTRACT Introduction: Lupus nephritis (LN) is one of the most prevalent and severe complications of systemic lupus erythematosus (SLE), requiring reliable urine and serum biomarkers to evaluate it. Anti-nucleosome and anti-C1q antibodies are associated with LN in several geographic regions. Also, southwest Colombia has a heterogeneous ethnicity, which motivated the evaluation of the frequency and relationship of such markers with LN in this region. Methods: A cross-sectional study was conducted in a health centre in south-west Colombia in 84 patients diagnosed with SLE (57 without LN; 27 with LN) between 2016 and 2018. Demographic and clinical and laboratory features, including anti-dsDNA, complement, and anti-C1q and anti-nucleosome antibodies were compared in these patients. ELISA immunoassays were performed to measure the antibodies of interest in blood samples. Statistical analysis was carried out using STATA14 software (StataCorp, College Station, Texas, USA). Quantitative variables were summarised as means or medians and compared with Mann-Whitney or Two-sample t test. Categorical variables were shown as proportions, and compared with Chi-squared or Fisher's exact test. Correlation analysis between quantitative variables was calculated using Spearman's correlation. Results: Of all 84 patients, 27 patients had LN, of which 16 (59.2%) had a positive test for anti-nucleosome antibodies and 10 (37%) for anti-C1q antibodies. An association was found between anti-C1q and proliferative forms of LN and newly diagnosed LN. A correlation was found between anti-nucleosome and anti-C1q antibodies, and anti-dsDNA and low serum complement concentrations. Conclusion: Although both markers were found in variable percentages in SLE patients and seem not to be specific markers of LN in our population, anti-C1q was associated with proliferative forms of LN and de novo LN.
RESUMEN Introducción: La nefritis lúpica (NL), una de las complicaciones más frecuentes y graves del lupus eritematoso sistémico (LES), requiere biomarcadores confiables de orina y suero para su evaluación. Los anticuerpos anti-nucleosoma y anti-C1q se asocian con la NL en varias regiones geográficas. En el suroccidente colombiano se asienta una etnia heterogénea, lo que motivó la evaluación de la frecuencia y la relación de dichos marcadores con NL en dicha región. Métodos: Realizamos un estudio transversal en un centro de salud en el suroccidente de Colombia, con 84 pacientes diagnosticados con LES (57 sin NL; 27 con NL) entre los anos 2016 y 2018. Se compararon las características demográficas, clínicas y de laboratorio, incluidos los anticuerpos anti-dsDNA, complemento, anti-C1q y anti-nucleosomas entre estos pacientes. Se realizaron inmunoensayos ELISA para medir los anticuerpos de interés en muestras de sangre. El análisis estadístico se llevó a cabo con el software Stata v.14 (Stata-Corp, College Station, Texas, EE. UU.). Las variables cuantitativas se resumieron como medias o medianas y se compararon con la prueba t de Mann-Whitney o Two-sample t test; las variables categóricas se mostraron como proporciones y se compararon con Chi-cuadrado o con la prueba exacta de Fisher. Para el análisis de correlaciones entre variables cuantitativas se calculó el coeficiente de correlación de Spearman. Resultados: Entre los 84 pacientes, 27 presentaban LN, de los cuales 16 (59,2%) tuvieron una prueba positiva para anticuerpos anti-nucleosoma y 10 (37%) para anticuerpos anti-C1q. Se encontró una asociación entre anti-C1q y formas proliferativas de NL, así como formas recientemente diagnosticadas de NL. Hubo una correlación entre los anticuerpos anti-nucleosoma y anti-C1q y el anti-dsDNA y las bajas concentraciones de complemento sérico. Conclusión: Aunque los 2 marcadores se encontraron en porcentajes variables de pacientes con LES y no parecen ser marcadores específicos de NL en nuestra población, la presencia de anti-C1q se asoció con formas proliferativas de NL y NL de novo.
Subject(s)
Humans , Lupus Nephritis , Lupus Erythematosus, Systemic , Antibodies , Weights and Measures , Immunoassay , Ethnicity , LaboratoriesABSTRACT
Objective@#To assess the association between lupus nephritis disease activity and anti-C1q antibodies.@*Methods@#The study analyzed the medical records of 98 patients with lupus nephritis (LN), 35 patients without lupus nephritis. LN disease activity was measured by the systemic lupus international collaborating clinics (SLICC) renal activity score of 2008. All biopsied tissues were scored based on the International society of nephrology/Renal pathology society (ISN/RPS) 2003 LN pathological typing standards, acute and chronic index scores were used to evaluate the activities of lupus. All patients were test for the levels of anti-dsDNA and anti-C1q antibodies using the enzyme-linked immuno sorbent assay (ELISA), C3, C4, 24-hour urinary protein performed in parallel. For normally distributed quantitative parameters, the differences between groups were assessed by t test. Mann-Whitney U test was performed for non-normally distributed data. The cut-off values were evaluated by using receiver operating characteristic (ROC). The Spearman methods were used to test correlations.@*Results@#Patients with LN had a higher levels of anti-C1q antibodies than patients without lupus nephritis [3.94 (10.2, 91.3) AU/ml与6.9 (2.0, 15.4) AU/ml; Z=-4.299, P<0.01]. Patients with inactive lupus nephritis had higher levels of C1q, C3, C4 than active LN (t=2.393, 3.777, 2.557; P<0.05). Patients with active lupus nephritis had higher levels of anti-C1q antibodies than inactive LN (Z=-4.632, P<0.01). Anti-C1q antibody levels were positively correlated with levels of 24-hour urinary protein, AI score (r=0.327, P<0.01) and SLICC score (r=0.493, P<0.01), and were negatively correlated with serum C1q (r=-0.373, P<0.01), C3 (r=-0.532, P<0.01) and C4 (r=-0.463, P<0.01). The optimal cutoff value of Anti-C1q for a diagnosis of active LN was 48.9 RU/ml, and the sensitivity and specificity were 62.5% and 80%, respectively. The area under the curve (AUC) was 0.771.@*Conclusion@#Anti-C1q antibodies are more closely correlated with renal disease activity, and anti-C1q antibody is an important serum marker for monitoring LN activity, but its pathological mechanism in the pathogenesis of LN still needs to be further explored.
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Abstract Introduction: Anti-nucleosome and anti-C1q antibodies demonstrated an association with the development of glomerulonephritis in systemic lupus erythematosus (SLE). Some investigators have proposed that monitoring anti- C1q and anti-nucleosome antibodies might be valuable for making predictions about lupus nephritis (LN) and assessment of disease activity as a non-invasive biological marker of renal disease. Objectives: The current study was proposed to investigate the presence of anti-C1q and anti-nucleosome antibodies in the sera of Egyptian patients with SLE and their association with LN. Methods: Eighty patients with SLE were included. Patients were classified into, a LN group including 40 cases with active LN (based on the results of renal biopsy and renal SLEDAI≥4) and a non renal SLE group including 40 patients (with no clinical or laboratory evidence of renal involvement that were attributed in the past or present to SLE). They were subjected to full medical history taking, clinical examination, routine laboratory investigations, measurement of antinuclear antibody (ANA), anti-ds DNA, anti-C1q & anti-nucleosome antibodies. Results: Anti-C1q antibody showed a statistically significant association with the presence of vasculitis and nephritis while anti-nucleosome antibody didn't show a significant association with the presence of any clinical features. Double positivity of anti-nucleosome and anti-C1q antibodies showed a statistically significant association with the presence of vasculitis and photosensitivity, high ECLAM score, elevated ESR, low serum albumin and low C3 levels. Conclusion: Serum anti-C1q antibody has a significant association with LN while double positive antibodies have a significant association with vasculitis and low C3 levels in Egyptian patients with SLE.
Subject(s)
Adult , Aged , Female , Humans , Male , Middle Aged , Pulmonary Medicine/methods , Glycogen Storage Disease Type II/complications , Glycogen Storage Disease Type II/diagnosis , Dried Blood Spot Testing/standards , Late Onset Disorders/diagnosis , Lung Diseases/complications , Biopsy , Glycogen Storage Disease Type II/blood , Glycogen Storage Disease Type II/enzymology , Early Diagnosis , alpha-Glucosidases/metabolism , Late Onset Disorders/blood , Late Onset Disorders/enzymology , Italy , Lung Diseases/blood , Muscles/surgery , Muscles/enzymologyABSTRACT
Objective:To investigate the clinical and laboratory characteristics of lupus nephritis(LN) patients by detecting the anti-nucleosome antibodies, anti-C1q antibodies and anti-double stranded antibodies(anti-ds DNA), and to clarify the risk factors of LN in the patients with systemic lupus erythematosus(SLE),and the significance of three kinds of antibodies in diagnosis of LN.Methods:A total of 120 SLE patients were selected and divided into LN group(n=60) and non-LN group(n=60).The ANAS data of 120 patients were retrospectively analyzed,the levels of anti-C1q antibodies were measured.The clinical symptoms and laboratory data of the patients with positive anti-dsDNA,-nucleosome and-C1q antibodies (3-pos group)and negative three kinds of antibodies(non 3-pos group) were analyzed in LN group.Results:The positive rate of anti-C1q antibody of the patients in LN group (40.00%) was higher than that in non-LN group (21.67%) (χ2=4.728, P=0.03).The positive rate of anti-dsDNA antibody in LN group was 66.67%, and it was 46.67% in non-LN group;the positive rates of the patients had significant difference between two groups (χ2=4.887, P=0.027).The positive rate of anti-nucleosome antibody in LN group was 58.33%, and it was 40.00% in non-LN group;the positive rates of the patients had significant difference between two groups (χ2=4.034, P=0.045).The positive rates of U1-snRNP, SmD1 and other antibodies Jo-1, SSA/Ro60kD, SSA/Ro52kD, SSB, ScL-70, CENP-B,and P0 had no significant differences between two groups(P>0.05).The levels of C3 and C4 and hemoglobinin of the patients in 3-pos group were higher than those innon 3-pos group (P0.05).The clinical symptoms were not statistically significant in 3-pos and non 3-pos groups (P>0.05).Conclusion:The anti-nucleosome, anti-C1q and anti-dsDNA antibodies are the risk factors of SLE complicated with LN;the positive antibodies can improve the diagnostic rate of LN.The 3-pos patients have more severe damage in complements and blood system with higher renal disease activities.
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Background : Detecting the active state of systemic lupus erythematosus (SLE) is important but challenging. This study aimed to determine the diagnostic accuracy of serum endothelial cell adhesion molecules (ICAM-1 and VCAM-1) and anti-C1q antibody in discriminating between active and non-active SLE. Methods: Using SELENA-SLE disease activity index (SLEDAI), 95 SLE patients (45 active and 50 non-active) were assessed. A score above five was considered indicative of active SLE. The blood samples were tested for serum ICAM-1, VCAM-1 and anti-C1q antibody using enzyme-linked immunosorbent assay (ELISA). Results: The levels of serum VCAM-1 and anti-C1q antibody were significantly higher in active SLE patients. Both VCAM-1 and anti-C1q were able to discriminate between active and non-active SLE ( p -value < 0.001 and 0.005, respectively). From the receiver operating characteristic curves (ROCs) constructed, the optimal cut-off values for VCAM-1 and anti-C1q antibody in discriminating between active and non-active SLE were 30.5 ng/mL (69.0% sensitivity, 60.0% specificity, PPV 58.5%, NPV 66.7%) and 7.86 U/mL (75.6% sensitivity, 80% specificity, PPV 77.3%, NPV 78.4%), respectively. However, serum ICAM-1 level was unable to discriminate between the two groups ( p -value = 0.193). Conclusion: Anti-C1q antibody demonstrated the best diagnostic accuracy in discriminating between active and non-active SLE patients
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Lupus nephritis (LN) is a severe complication of systemic lupus erythematosus (SLE). A retrospective analysis was carried out on a group of 24 patients with SLE to evaluate whether the presence of anti-C1q antibodies (anti-C1q) is related to renal involvement and to explore the behaviour of anti-C1q with respect to LN during a four-year follow-up period. A first serum sample stored at the serum bank, taken not more than three years after SLE diagnosis and one serum sample per year for the subsequent four years were used to detect anti-C1q. Lupus clinical manifestations and serological markers of activity corresponding to the date of each serum sample selected were collected from medical records. In the first serum sample, anti-C1q were found in 8 active SLE. LN was confirmed by histology in 5/8 patients who were positive for anti-C1q and in 1/16 patients who were negative for these autoantibodies (p = 0.0069). Three patients (3/8) had anti-C1q without renal involvement but with lupus skin manifestation. Anti-C1q levels decreased in 3/5 patients with LN who responded to treatment and remained higher in 2/5 patients who needed a new renal biopsy which showed severe renal disease. The 15 patients without severe kidney disease and anti-C1q negative at diagnosis did not develop LN and anti-C1q remained negative in the 4 years of follow up. Anti-C1q were found in SLE patients with active renal involvement or with lupus skin disease. The absence of anti-C1q seemed to be linked to low probabilities of renal involvement.
La nefritis lúpica (NL) es una complicación grave del Lupus Eritematoso Sistémico (LES). Se analizó retrospectivamente en 24 pacientes con LES si la presencia del anticuerpo anti-C1q (anti-C1q) se asociaba con NL y el comportamiento del anti-C1q respecto a la NL en un período de seguimiento de cuatro años. El anti-C1q se determinó en una primera muestra de suero no distante en más de tres años del diagnóstico de LES y en una muestra por año en los siguientes cuatro años. Se obtuvo información de las historias clínicas, sobre manifestaciones clínicas de LES y marcadores serológicos de actividad para las fechas de selección de cada suero. En la primera muestra de suero se detectó anti-C1q en 8 pacientes con LES activo. NL fue confirmada por histología en 5 de ellos y en uno de 16 pacientes con anti-C1q negativos (p = 0.0069); 3 de 8 pacientes fueron anti-C1q positivos sin NL y con lesiones en piel. Los niveles de anti-C1q disminuyeron en 3/5 pacientes con NL que respondieron al tratamiento y se mantuvieron aumentados en 2/5 que necesitaron una nueva biopsia, que evidenció compromiso renal grave. Los 15 pacientes sin enfermedad renal grave y con anti-C1q negativo al diagnóstico no desarrollaron NL y el anti-C1q se mantuvo negativo en los 4 años de seguimiento. El anti-C1q se asoció en pacientes con LES a NL activa o con compromiso en piel. La ausencia del anti-C1q parecería relacionarse a un menor riesgo de desarrollar nefropatía lúpica.
Subject(s)
Adolescent , Adult , Female , Humans , Male , Middle Aged , Young Adult , Autoantibodies/blood , Complement C1q/immunology , Lupus Erythematosus, Systemic/complications , Lupus Nephritis/immunology , Biomarkers/blood , Complement C1q/analysis , Follow-Up Studies , Lupus Erythematosus, Systemic/immunology , Lupus Nephritis/etiology , Retrospective StudiesABSTRACT
Resumen El compromiso renal en el lupus eritematoso sistémico (LES) es uno de los mayores determinantes del curso y pronóstico de estos pacientes. Existe evidencia de la asociación de anticuerpos anti-C1q y el desarrollo de nefritis lúpica. El objetivo de este estudio fue determinar la prevalencia de anticuerpos anti-C1q y su asociación con nefritis lúpica en pacientes colombianos con LES. Métodos: Estudio de corte transversal en el cual se incluyeron 80 pacientes con diagnóstico de LES según criterios del Colegio Americano de Reumatología. La cuantificación de anticuerpos anti-C1q séricos se realizó por ELISA, se consideraron positivas concentraciones ≥15 U/ml. Resultados: Los pacientes eran predominantemente mujeres (87%) y 43,7% tuvieron proteinuria >0,5 g/día, la cual fue más común en pacientes jóvenes y apareció tempranamente en la enfermedad. Cuarenta y cuatro (55%) de los pacientes tenían anticuerpos anti-C1q positivos, en quienes la proteinuria fue más frecuente (OR=4.3, IC95% 1.7 - 11, p=0.003). Se encontró correlación inversa débil entre los títulos de anti-C1q, el consumo de C3 (r=-0.54, p<0.001) y la depuración de creatinina (r=-0.33, p=0.035); una correlación directa débil, con la proteinuria (r=0.35, p=0.024) y la actividad de la enfermedad, la cual se determinó con el Índice de Actividad de Enfermedad (SLEDAI) (r=0.48, p<0.0001). Conclusiones: Los anticuerpos anti-C1q pueden ser útiles en la evaluación de la nefritis lúpica activa, y podrían ser implementados como un marcador diagnóstico de nefritis lúpica y como un posible marcador de actividad de la enfermedad en pacientes con LES, tal como lo ha sugerido la Liga Europea contra el Reumatismo (EULAR).
Summary Renal involvement in systemic lupus erythematosus (SLE) is one of the major determinants Anti-C1q antibodies of the course and prognosis of these patients. There is evidence of the association of Anti-DNA antibodies anti-C1q antibodies and the development of lupus nephritis. The aim of this study was to determine the prevalence of anti-C1q antibodies and its association with lupus nephritis in Colombian patients with SLE. Methods: 80 SLE patients as defined by the American College of Rheumatology criteria. Quantification of anti-C1q antibodies in patients' sera was performed by ELISA and concentrations greater than 15U/ml were considered positive. Results: Patients were predominantly women (87%) and 43.7% of them had proteinuria > 0.5 g / 24 hours which was more common in younger patients and early in the course of the disease. Forty-four (55%) of patients had positive anti-C1q, in whom, proteinuria was more frequent (OR = 4.3 95% CI 1.7 - 11, p = 0.003). A weak inverse correlation between anti-C1q titers, C3 consumption (r = -0.54, p <0.001) and creatinine clearance was found (r = -0.33, p = 0.035); similarly, we also found a weak direct correlation with proteinuria (r = 0.35, p = 0.024) and disease activity ascertained with the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) (r = 0.48, p <0.0001). Conclusions: Anti-C1q antibodies might be valuable for the evaluation of active lupus nephritis, and might be valuable for the evaluation of active lupus nephritis, and could be included as a diagnostic marker of lupus nephritis and maybe as a marker for disease activity, as suggested by the European League Against Rheumatism (EULAR).
Subject(s)
Humans , Antibodies , Lupus Erythematosus, Systemic , Lupus NephritisABSTRACT
Objective To investigate the association of anti-C1q antibody with disease activity and lupus nephritis in patients with systemic lupus erythematosus(SLE). Methods The serum Level of anti-C1q antibody was determined in 35 patients with SLE by ELISA. The correlation between anti-C1q level and other disease activity parameters, such as SLEDAI score, anti-dsDNA antibody, C3, C4 and CH50 levels, was analyzed. Results Anti-C1q antibody was positive in 51.4% of patients with SLE, the positive rates in patients with active nephritis and without one was 77.8%(14/18) and 42.3%(22/52), respectively, and that was significantly higher in the former than in the later(P