Third Component of Complement (C3) and Fourth Component of Complement (C4) in Discoid and Systemic Lupus erythematosus

Objective.Patients with systemic lupus erythematosus (SLE) frequently undergo repeat testing for antibodies against extractable nuclear antigens (anti-ENA), but it is not known whether this is necessary or cost-effective. This study characterized the frequencies of changes in anti-ENA, anti–dsDNA, and complement C3 and C4 upon repeat testing.Methods.Chart review was done at one site of 130 patients with SLE enrolled in the 1000 Canadian Faces of Lupus prospective registry with annual antibody and complement testing. We determined the frequency of seroconversion (changes) on the next test and over the entire followup given 1 or multiple consistent results, and the cost to detect these changes.Results.Overall, 89.4% of patients had no changes in anti-ENA screening results from the first available test, 3.3% changed from negative to positive, and 7.3% from positive to negative. Following a single anti-ENA test, 3.9% of negative tests changed to positive and 4.2% of positive changed to negative on the next test. After multiple consistent tests, the frequencies of changes progressively declined. No changes from the first test were observed in anti-dsDNA, C3, and C4 in 60.8%, 83.3%, and 75.4% of patients, respectively. After 2 consistent anti-ENA tests, the cost to detect 1 change was above US$2000.Conclusion.Anti-ENA results change infrequently, especially following 1 or more negative tests. The high cost and lack of evidence that changes affect management suggest that repeating anti-ENA tests routinely is unnecessary. Anti-dsDNA and complements change more frequently after an abnormal result, but less after a normal value.

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Complement deficiency in pediatric-onset systemic lupus erythematosus

Journal of Laboratory Physicians ◽

10.4103/jlp.jlp_171_17 ◽

2018 ◽

Vol 10 (02) ◽

pp. 232-236 ◽

Cited By ~ 2

Author(s):

Parisa Afzali ◽

Anna Isaeian ◽

Peyman Sadeghi ◽

Bobak Moazzami ◽

Nima Parvaneh ◽

...

Keyword(s):

Systemic Lupus Erythematosus ◽

Lupus Erythematosus ◽

Musculoskeletal Symptoms ◽

Complement C3 ◽

Complement Deficiency ◽

Control Group ◽

Systemic Lupus ◽

Cutaneous Manifestations ◽

Pediatric Onset ◽

Onset Systemic Lupus Erythematosus

Abstract BACKGROUND: Pediatric-onset systemic lupus erythematosus (pSLE) accounts for about 10%-20% of all patients with SLE. Deficiencies in early complement components of the classical pathway are the strong genetic risk factor for the development of SLE. In this study, clinical and laboratory manifestations of both complement-deficient and normal complement pSLE patients were compared. MATERIALS AND METHODS: To investigate clinical and immunological manifestations of pSLE in Iran, 36 consecutive pSLE patients (onset before 18 years) who were followed up over a period of 2 years, were studied. Complement C1q and C2 levels were measured using radial immunodifusion assay and complement C3 and C4 levels were measured using nephelometry. Medical records were retrospectively evaluated from patient database of Children Medical Center Hospital. Data were assessed through descriptive analysis (confidence interval = 95%), paired t-test, and Pearson correlation test. RESULTS: Twenty-one patients (58%) had at least one component of complement deficiency. Ten patients (27%) had low C1q level, 11 patients (30.5%) had low C2, nine patients (25%) had low C3, and four patients (11%) had low C4 level. Serum level of complement in pSLE was significantly lower than the control group, except C4 (P = 0.005). The low C1q patients had an earlier age of onset of disease (P < 0.0001). The cutaneous manifestations were more frequent and much more severe in pSLE with low complement (100% vs. 73%). The frequency of renal and musculoskeletal symptoms was equal, but renal morbidity was more common in pSLE with low complement. Positivity for anti-ds-DNA was less common in pSLE with low complement (71% vs. 86%). CONCLUSION: In pSLE patients with early disease onset and more aggressive SLE manifestations and negative anti-ds-DNA test, complement deficiency should be considered.

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Galectin-9 is an easy to measure biomarker for the interferon signature in systemic lupus erythematosus and antiphospholipid syndrome

Annals of the Rheumatic Diseases ◽

10.1136/annrheumdis-2018-213497 ◽

2018 ◽

Vol 77 (12) ◽

pp. 1810-1814 ◽

Cited By ~ 20

Author(s):

Lucas L van den Hoogen ◽

Joël A G van Roon ◽

Jorre S Mertens ◽

Judith Wienke ◽

Ana Pinheiro Lopes ◽

...

Keyword(s):

Systemic Lupus Erythematosus ◽

Disease Activity ◽

Antiphospholipid Syndrome ◽

Lupus Erythematosus ◽

Area Under The Curve ◽

Serum Levels ◽

Complement C3 ◽

Tumour Necrosis Factor Receptor ◽

Systemic Lupus ◽

Dsdna Antibody

ObjectiveThe interferon (IFN) signature is related to disease activity and vascular disease in systemic lupus erythematosus (SLE) and antiphospholipid syndrome (APS) and represents a promising therapeutic target. Quantification of the IFN signature is currently performed by gene expression analysis, limiting its current applicability in clinical practice. Therefore, the objective of this study was to establish an easy to measure biomarker for the IFN signature.MethodsSerum levels of galectin-9, CXCL-10 (IP-10) and tumour necrosis factor receptor type II (TNF-RII) were measured in patients with SLE, SLE+APS and primary APS (PAPS) and healthy controls (n=148) after an initial screening of serum analytes in a smaller cohort (n=43). Analytes were correlated to measures of disease activity and the IFN signature. The performance of galectin-9, CXCL-10 and TNF-RII as biomarkers to detect the IFN signature was assessed by receiver operating characteristic curves.ResultsGalectin-9, CXCL-10 and TNF-RII were elevated in patients with SLE, SLE+APS and PAPS (p<0.05) and correlated with disease activity and tissue factor expression. Galectin-9 correlated stronger than CXCL-10 or TNF-RII with the IFN score (r=0.70, p<0.001) and was superior to CXCL-10 or TNF-RII in detecting the IFN signature (area under the curve (AUC) 0.86). Importantly, in patients with SLE(±APS), galectin-9 was also superior to anti-dsDNA antibody (AUC 0.70), or complement C3 (AUC 0.70) and C4 (AUC 0.78) levels in detecting the IFN signature.ConclusionGalectin-9 is a novel, easy to measure hence clinically applicable biomarker to detect the IFN signature in patients with systemic autoimmune diseases such as SLE and APS.

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