Hypocomplementemia in systemic lupus erythematosus and primary antiphospholipid syndrome: prevalence and clinical significance in 667 patients

The objective of the study was to analyse the prevalence and clinical significance of hypocomplementemia in a large series of patients diagnosed either with systemic lupus erythematosus (SLE) or with primary antiphospholipid syndrome (APS) and its association with the main clinical, hematological and immunological features of these diseases. Between 1992 and 2003, complement determinations (C3 and C4 levels, CH50 activity) were performed in 597 consecutive patients diagnosed with SLE (530 women and 67 men, mean age 32.6 years) and 70 with primary APS (57 women and 13 men, mean age 38.7) visited in our department. Complement determinations are routinely made at the first visit of patients and yearly during the follow-up. SLE and primary APS were diagnosed according to current classification criteria. Hypocomplementemia was detected in 371 (62%) of SLE patients. Compared with patients with normal complement values, those with hypocomplementemia showed a higher prevalence of female gender (P < 0.001), fever (P = 0.021), nephropathy (P < 0.001), cutaneous vasculitis (P = 0.023), positive anti-dsDNA antibodies (P = 0.012) and cryoglobulinemia (P < 0.001). In addition, patients with hypocomplementemia showed a higher prevalence of APS-related features such as hemolytic anemia (P = 0.001) and antiphospholipid antibodies (P < 0.001). Hypocomplementemia was prospectively related to accumulated hospitalization in SLE patients but not with the accumulated number of lupus flares or with the survival after follow-up of five years. In contrast, 33 (47%) patients with primary APS presented low complement values, which were associated with a higher prevalence of livedo reticularis (P = 0.022), thrombocytopenia (P = 0.004), lupus anticoagulant (P = 0.013), positive IgM-aCL (P = 0.039), positive ANA (P = 0.002) and anti-dsDNA (P = 0.046). The diagnostic value of hypocomplementemia in patients with SLE is based on the association with disease activity, immune-complex mediated manifestations (glomerulonephritis, cryoglobulinemia) and APS-related features (livedo reticularis, hemolytic anemia and aPL). Hypocomplementemia was found in nearly half of patients with primary APS, and was associated with some APS features (livedo reticularis, thrombocytopenia, aPL) but also with SLE-related immunological markers (ANA and anti-dsDNA), identifying a subset of patients with primary APS with a higher risk of evolving to SLE. These results clearly support the routine determination of complement factors in the clinical follow-up of patients with SLE and primary APS.     

Diagnostic and prognostic significance of different antinuclear antibodies in more than 1000 consecutive Albanian patients with rheumatic diseases.

In an unselected population of 1390 consecutive Albanian patients with rheumatic diseases (RD) and other miscellaneous non-rheumatic diseases (MNRD), for whom antinuclear antibody (ANA) testing was requested, we calculated the diagnostic sensitivity, specificity and positive predictive value (PPV) of ANA positive results, ANA titres over 1:100, anti-native DNA (nDNA), anti-Sm, anti-U1 RNP, anti-SSA (Ro) anti-SSB (La) and anti-non-identified extractable nuclear antigen (NIENA) antibodies. The PPVs of these ANA types were found to be appreciable only for systemic lupus erythematosus (SLE); only the positive predictive value of ANA for SLE (26.4%) was lower than that for RA (34.3%). The anti-snRNP (Sm/U1RNP) positive SLE patients were more likely to have over 4 of the ARA criteria for SLE, ANA titres over 1:100, and anti-nDNA antibodies, in contrast with the anti-snRNP negative subgroup. On the other hand, the anti-ENA positive and anti-nDNA positive SLE patients generally showed higher frequencies of renal disease, over 4 of the criteria for SLE and ANA titres over 1:100, compared to anti-ENA positive and anti-nDNA negative patients. Our data suggest that the association of anti-snRNP antibodies with a more severe form of SLE is not to be attributed to these antibodies themselves, but rather to their close association with the concomitant presence of anti-nDNA antibodies.     

Utility of anti-Sm,anti-RNP,anti–Ro/SS-A,and anti–La/SS-B (extractable nuclear antigens) detected by enzyme-linked immunosorbent assay for the diagnosis of systemic lupus erythematosus

Objective. To determine the utility of anti-extractable nuclear antigen (anti-ENA) antibodies detected by enzyme-linked immunosorbent assay as a predictor for the diagnosis of systemic lupus erythematosus (SLE). Methods. Among 2,185 serum samples sent for testing for antinuclear antibodies (ANA) by indirect immunofluorescence, 259 consecutive patients with positive ANA were identified. Medical charts of these patients were reviewed to assess the clinical diagnosis, with the reviewer having no knowledge of the anti-ENA result. Clinical data were abstracted for all patients, and diagnoses established using American College of Rheumatology criteria. The utility of ENA antibodies in the diagnosis of SLE was determined by univariate and multivariate analysis among all patients who were positive for ANA, patients who were positive for ANA and for anti-double-stranded DNA (anti-dsDNA), and patients who were positive for ANA and negative for anti-dsDNA. Clinical differences between SLE patients with and those without anti-ENA antibodies were assessed. Results. Anti-ENA antibodies, especially anti-Ro/SS-A, showed strong predictive diagnostic value among ANA+/anti-dsDNA– patients, but were of no utility among ANA+/anti-dsDNA+ patients. The only clinical manifestations that were more common among anti-ENA+ SLE patients were pleuritis and the use of hydroxychloroquine. Conclusion. The presence of anti-ENA antibodies, especially anti-Ro/SS-A, is a useful predictor for the diagnosis of SLE, primarily among patients attending a referral rheumatology center who are positive for ANA and negative for anti-dsDNA. No major clinical differences were noted among ANA+ SLE patients with versus those without ENA.     

Anti-dsDNA antibodies in sarcoidosis

BACKGROUND: Sarcoidosis is a chronic multisystem disorder characterized by an exaggerated cellular immune response to antigens with the production of various antibodies including rheumatoid factor and antinuclear antibodies (ANA). The prevalence and significance of antibodies to double-stranded DNA (anti-dsDNA) in sarcoid patients is unknown. The occurrence of anti-dsDNA antibodies is known to be a specific marker of systemic lupus erythematosus (SLE). Sarcoidosis can occur with SLE. It is unclear if anti-dsDNA antibodies in patients with sarcoidosis signify the eventual development of SLE. OBJECTIVES: To determine the prevalence of anti-dsDNA antibodies in patients with sarcoidosis in a university hospital and their significance in predicting the diagnosis of associated SLE. METHODS: In a retrospective study, 34 patient files with diagnosed sarcoidosis in a university hospital during a period of 15 years were reviewed for serological markers, including ANA, anti-dsDNA, and immunoglobulin and C3 levels. The occurrence of SLE in these patients also was evaluated. RESULTS: ANA were positive in 10 of 34 of the patients screened. Two patients with sarcoidosis had antibodies to dsDNA. C3 levels in these 34 patients were an average of 87.7 +/- 25.3 mg/100 mL, which is within the normal range. IgG immunoglobulin levels were an average of 2,206 +/- 999 mg/100 mL, which was above normal limits. The 2 patients who were positive for anti-dsDNA had normal C3 levels and SLE did not develop during a follow-up period of 10 to 15 years. CONCLUSIONS: Anti-dsDNA antibodies may occur in patients with sarcoidosis, but their presence does not predict the subsequent development of SLE.     

Anti-chromatin and anti-C1q antibodies in systemic lupus erythematosus compared to other systemic autoimmune diseases

OBJECTIVE: To evaluate the prevalence, sensitivity, and specificity of anti-chromatin and anti-C1q antibodies in systemic lupus erythematosus (SLE) and lupus nephritis compared to small vessel vasculitis and other connective tissue diseases. To provide long-term follow-up data for anti-chromatin antibodies in lupus nephritis. METHODS: We determined the significance of anti-nuclear antibodies (ANA), anti- double-stranded DNA (anti-dsDNA), anti-chromatin, and anti-C1q antibodies, as well as complement factors C3 and C4, in relation to disease activity in SLE patients with (n = 47; long-term follow-up data for 33 patients) and without (n = 31) biopsy-confirmed lupus nephritis, microscopic polyangiitis (n = 37), Wegener's granulomatosis (n = 66), primary Sj?gren's syndrome (n = 17), limited scleroderma (CREST syndrome) (n = 6), and progressive systemic scleroderma (PSS) (n = 11). RESULTS: Anti-chromatin antibodies were more specific and sensitive than anti-C1q antibodies in distinguishing SLE patients from those with other systemic autoimmune diseases [anti-chromatin: sensitivity 64.1%, specificity 99.2%, odds ratio (OR) 219.6; anti-C1q: sensitivity 50%, specificity 72.6%, OR 2.65]. Anti-C1q antibodies were present in 75% of patients with Sj?gren's syndrome and 35.1% of patients with microscopic polyangiitis. Anti-chromatin antibodies could identify SLE in patients with positive ANA but negative anti-dsDNA antibodies. Persisting anti-chromatin antibodies indicated SLE disease activity, even if anti-dsDNA antibodies had become negative. In long-term follow-up, those SLE patients with negative anti-dsDNA antibodies but persisting ANA and anti-chromatin antibodies relapsed if immunosuppression had been tapered. Anti-chromatin antibodies correlated with the SLE disease activity index (SLEDAI) as a marker of disease activity. CONCLUSIONS: The measurement of anti-chromatin, but not anti-C1q, antibodies in patients with systemic autoimmune diseases increases diagnostic sensitivity and specificity for SLE and assists in treatment decisions in anti-dsDNA-negative patients.     

Systemic lupus erythematosus in Kuwaiti children: organ system involvement and serological findings

The course and severity of systemic lupus erythematosus (SLE) in children is generally similar to the adult form with potential serious organ system involvement, there are, however, factors that influence the prevalence and clinical behavior of the disease. Our objective was to analyse the organ system involvement and immunological findings in Kuwaiti children with SLE in relation to gender and age of onset and compare these findings to that in published reports. Organ system involvement and serologic profiles were analysed in 35 children with SLE. The major organ systems studied were: renal, hematological, cardiac, pulmonary, hepatic and the central nervous system. The prevalence of ANA, anti-dsDNA, anti-Sm, SSA, SSB and anti-cardiolipin antibodies were studied in addition to complement C3 and C4 levels. The results showed that a high percentage of children had hematological involvement (34%); thrombocytopenia (23%) and hemolytic anemia (20%). Renal involvement was proven by biopsy in only 10 children (29%). Neuropsychiatric manifestations were seen in five (14%) of patients. Males had a tendency for major organ involvement relative to females. All patients had positive ANA tests. All males had positive anti-dsDNA tests compared to 86% of female patients. The most significant finding in this study is the high frequency of hematological manifestations and the relatively low incidence of renal disease and neuropsychiatric abnormalities in Kuwaiti children with SLE.     

Clinical and serological correlates of anti-Sm autoantibodies in Chinese patients with systemic lupus erythematosus: 1,584 cases

To investigate the association of anti-Sm antibodies with clinical and serological features in systemic lupus erythematosus. A group of 1,584 patients with SLE was recruited. Clinical and laboratory data were compared between patients with and without anti-Sm antibodies. There were 1,424 females and 160 males, the mean age of the patients was 33.2 ± 12.3 years, and the mean duration of disease was 32.5 ± 59.4 months. A total of 469 (29.6%) were anti-Sm antibodies positive. The presence of anti-Sm antibodies was associated with arthritis, renal involvement, malar rash, vasculitis and low serum complement C3. The positive rate of anti-nuclear, anti-dsDNA, anti-La/SSB and anti-U1RNP antibodies were significant higher in anti-Sm positive group when compared with anti-Sm negative group. A trend towards a higher presence of anti-Sm antibodies related to an early disease onset was observed. In conclusion, Anti-Sm antibodies are associated with lupus related clinical and laboratory profiles and correlated significantly with disease activity.     

Speckled antinuclear antibodies in keratinocytes--what does it mean?

OBJECTIVE: Epidermal in vivo nuclear staining is occasionally noted in the lupus band test (LBT) in patients with connective tissue diseases (CTD). The exact clinical significance of this finding remains unelucidated, especially in association with a positive LBT We have reviewed the clinical and serological characteristics of patients with in vivo-bound antinuclear antibodies (ANA) in keratinocytes. METHODS: Between 1990-1999 speckled IgG staining in keratinocyte nuclei was observed in 31 LBT specimens. We had detailed clinical and laboratory data for 22/31 patients. The present study comprises 22 patients with in vivo-bound ANA (8 cases with mixed CTD (MCTD), 10 with systemic lupus erythematosus (SLE), 2 with Sj?gren's syndrome (SS), one with undefined CTD and one clinically healthy mother of a child with neonatal lupus erythematosus), and 22 consecutive CTD patients (2 MCTD, 15 SLE, 5 SS) without in vivo-bound ANA. Antinuclear, anti-dsDNA and anti-extractable nuclear antigens (ENA) antibodies were determined using indirect immunofluorescence and ELISA methods. RESULTS: A significant difference (p < 0.01) in anti-RNP antibodies between patients with and without in vivo-bound ANA was observed. Consequently, there was a strong association of in vivo-bound ANA and anti-RNP antibodies (p < 0.01). In SLE patients with in vivo-bound ANA the incidence of nephropathy was significantly lower (p < 0.01), regardless of LBT positivity. In SLE patients there were no differences in LBT positivity, anti-dsDNA antibodies and complement consumption between groups. CONCLUSION: Our study implies that the presence of speckled ANA in keratinocytes in LBT may be useful in the diagnosis of MCTD and in the prognosis of renal involvement, especially in SLE patients.     

Is there a predisposition for the development of autoimmune diseases in patients with fibromyalgia? Retrospective analysis with long term follow-up

The objectives of the study were to evaluate the prevalence of antinuclear antibodies (ANA) in patients with fibromyalgia (FM) and the probability of the development of clinically overt connective tissue diseases. Four hundred and fifty FM patients were compared to 129 healthy matched blood donors. ANA testing was performed by immunofluorescence on rat tissue sections; in case of highly positive results, ANA were specified further by ELISA and immunodiffusion. All ANA positive FM patients were invited for a control examination. The ANA negative patients received a questionnaire, which was designed to identify those patients with possible connective tissue diseases (CTD). There was no significant difference in the frequency of ANA or thyroid antibodies between patients and controls (11.6% vs. 7%). Two patients had developed SLE: one was already ANA/anti-dsDNA positive at time of first diagnosis of FM; in the other, specific antibodies and SLE-related symptoms developed after 4.5 years. The probability for FM patients to develop CTD (SLE) within one year is 0.0027%, which is comparable to the incidence of SLE in the general population (0.005%). The risk of CTD is not increased in FM. The detection of ANA does not predict the development of CTD. However, in individual cases, FM may be an early sign of an autoimmune disease.     

Relation between serological data at the time of biopsy and renal histology in lupus nephritis

Summary As autoantibodies are thought to participate in the pathogenesis of renal inflammation in systemic lupus erythematosis (SLE) we investigated associations between serological markers of disease activity in SLE and the activity of renal histopathological lesions in thirty-five patients with lupus nephritis (LN). We found the following prevalence of serum auto-antibodies in LN: IgG antinuclear antibodies (ANA) 100%, IgM ANA 69%, IgA ANA 60%, IgG anti-dsDNA 60%, IgM antidsDNA 71%, IgA anti-dsDNA 60%, anti-RNP 20%, anti-Sm 14%, anti-SSA 31%, anti-SSB 14%, anti-histone 37%, anti-cardiolipin 80% and antibody to ribosomal protein (anti-P) 6%. No correlation was found between serological parameters and the WHO-classification of biopsies. The activity-index of histological lesion, assessed according to the NIH-renal histology scoring system, correlated with IgM ANA and IgM anti-dsDNA titers. Of all the specific features of histological renal inflammation, glomerular proliferation showed the best overall correlation with serological parameters of disease activity. Anticardiolipin antibodies were correlated with overall disease activity, but not with renal histological activity. Thus, serological markers of disease activity did not adequately reflect the amount of renal inflammation in LN and cannot replace renal biopsy as a diagnostic tool.     

Clinical significance of antinuclear antibody in patients with idiopathic thrombocytopenic purpura]

The clinical significance of antinuclear antibodies (ANA) in patients with chronic idiopathic thrombocytopenic purpura (ITP) was evaluated. Serum samples of 55 patients with ITP without clinical features of systemic lupus erythematosus (SLE) were examined. The average follow-up period was 5.5 years. Positive ANA was found in 23 of the 55 patients. Twelve of these 23 showed a high-titer of ANA. There was no difference in platelet counts between ANA positive patients and negative patients, and there was no correlation between platelet counts and antibody titers. Ten of the 23 positive sera had precipitating antibodies to nuclear antigens; 7 SS-A and 3 RNP antibodies. The platelet counts of the 7 cases with anti-SS-A antibody positive were slightly low compared with those of the anti-SS-A antibody negative patients. None of the 10 patients developed SLE during the average follow-up period of 8.1 years. These results suggest that ITP patients who have a high-titer of ANA or antibody against SS-A do not always develop SLE. It was concluded that ANA with a high titer or precipitin to nuclear antigens, particularly SS-A, dose not predict a high risk of developing SLE in the future.     

Studies of Filipino patients with systemic lupus erythematosus: autoantibody profile of first-degree relatives

This study surveyed the frequency of autoantibodies among un-affected first-degree relatives (FDRs) of Filipino systemic lupus erythematosus (SLE) patients compared with healthy un-related Filipino controls. The sensitivity, specificity and predictive value of the autoantibodies for SLE diagnosis were also assessed in this Filipino cohort. Filipino patients included in the University of Santo Tomas (UST) Lupus Database and un-affected FDRs were recruited. Healthy controls included those with no known personal or family history of autoimmune disease. The following autoantibodies were tested in all subjects: anti-nuclear antibody (ANA), anti-dsDNA, anti-Ro/SSA, anti-chromatin, anti-thyroid microsome, and anti-cardiolipin antibodies. Participants included 232 SLE patients, 546 FDRs, and 221 healthy controls. Median age of patients was 27 (range 8-66) years with median disease duration of 27.5 (range 1-292) months. Median age of FDRs was 42.0 (range 5-87) years. Compared with healthy controls, there were significantly more FDRs with positive ANA at titers 1?:?40 to 1?:?160 (p?相似文献   

Clinical significance of low molecular weight IgM in patients with systemic lupus erythematosus

The presence of low molecular weight (LMW) IgM was found in 45% of patients with systemic lupus erythematosus (SLE). Complete chart analysis of clinical and laboratory variables was done on 39 patients with negative LMW IgM (Group 1) and on 40 patients with positive LMW IgM (Group 2). There were statistically significant differences between the 2 groups related to age at onset, hemoglobin concentration, IgM levels, and levels of anti-dsDNA. There were 12 known deaths among the 40 patients in the positive group (30.0%) and only 4 known deaths among the 39 patients in the negative group (10.26%), p less than 0.1. There were no significant intergroup differences of race, sex, mucocutaneous manifestations, arthritis, positive ANA, positive serologic test for syphilis by rapid plasma reagent, Coombs' positive anemia, thrombocytopenia, serositis, incidence of renal and central nervous system involvement. Our study shows that LMW IgM occurred in about half of the patients with SLE. Patients with positive LMW IgM compared to those without it had greater mortality at an earlier age.     

Immunological abnormalities in primary APS evolving into SLE: 6 years follow-up in women with repeated pregnancy loss.

We have performed a prospective study to determine the prevalence of immunological abnormalities and the evolution from primary antiphospholipid syndrome (APS) into systemic lupus erythematosus (SLE) in women who had had unexplained repeated pregnancy loss (PL) and APS. Of 105 women with abortions or fetal deaths, 33(31%) fulfilled criteria for APS. Among these patients with primary APS, 24% had antinuclear antibodies (ANA), 91% had elevated circulating immune complexes (CIC), 70% had low total haemolytic complement (CH100), 52% had low levels of complement 4 (C4) and 30% had low levels of complement 3 (C3), in a significantly higher prevalence than women whose pregnancies were successful (control group). Through out a 6 y follow-up, 3 (9%) of the patients with APS who had autoimmune related abnormalities when entered into the study developed features of lupus like disease (LLD) or fullblown SLE. Our findings suggest that women with unexplained repeated PL with APS who presented with positive ANA, high levels of CIC, low levels of CH100, C3 and C4, may define a subset of patients exhibiting immunological alterations similar to those of SLE. These parameters may help in the assessment of prognosis in APS patients with PL. Those patients should be carefully surveyed with regard to the development of connective tissue diseases.     

High frequency of Smith autoantibodies in Omani patients with systemic lupus erythematosus

This study was conducted to investigate the frequency and significance of some antinuclear autoantibodies in Omani patients with systemic lupus erythematosus (SLE). Anti-nuclear antibodies (ANA), anti-double stranded-DNA (anti-dsDNA), and anti-Smith (anti-Sm) autoantibodies were investigated in 60 Omani patients clinically diagnosed with SLE according to the American College of Rheumatology Criteria. The SLE group included 57 females and 3 males with an average age of 26 years. In addition, a group of 60 healthy Omanis (26 females and 34 males; average age 25 years) was used as a control. ANA patterns and autoantibody profile were assayed by indirect immunofluorescence assay using Hep-2 cells and liver/kidney/stomach tissue, respectively. Anti-dsDNA were examined by enzyme-linked immunosorbent assays; anti-Sm antibodies were measured by immunoblotting technique. Out of the 60 SLE patients, 59/60 (98.3%) were seropositive for ANA. Anti-dsDNA and anti-Sm each was detected in 50/60 (83.3%) of the Omani patients. The homogenous pattern of ANA was detected in 30/60 (50%) of patients, whereas the frequency of fine-speckled and coarse-speckled was 16/60 (26.7%) and 6/60 (10%), respectively. High titers (≥1:320) of ANA was detected in 56/60 (93.3%) of SLE patients. High titers of anti-Sm were detected in 22/60 (33.3%) of patients. High titers (>100 IU/ml) of anti-dsDNA were detected in 40/60 (66.7%) of patients. In the control group, ANA were detected in 8/60 (13.3%) but at low titers, whereas anti-dsDNA and anti-Sm were not detected in the healthy control group. This study shows that anti-Sm is as important as the anti-dsDNA for confirming the diagnosis of SLE and that anti-Sm occurs at a much higher frequency (83.3%) than that reported in other populations indicating the importance of this specific autoantibody for the diagnosis and possibly prognosis of Omani SLE patients.     

Clinical significance of antinuclear antibodies. Comparison of detection with immunofluorescence and enzyme-linked immunosorbent assays

Objective. To compare the measurement of antinuclear antibodies (ANA) by immunofluorescence and by 6 different commercial enzyme-linked immunosorbent assays (ELISAs) in clearly defined patient groups and serum samples. Methods. Serum samples were derived from 3 sources: 1) patients with a known clinical diagnosis of systemic lupus erythematosus (SLE) (group 1), 2) sera with known monospecific ANA reactivity (group 2), and 3) sera from consecutive patients for whom ANA testing had been ordered (group 3). Each of these sera was tested for the presence of ANA by immunofluorescence on HEp-2 cells, and by using each of 6 commercially available ELISA ANA kits. Results. In patients with known clinical SLE, 88% were ANA positive by immunofluorescence. Positivity with the different ELISAs ranged from 62% to 90%. While most ELISAs successfully detected antibodies to SS-A, RNP, and Sm, there were significant differences between assays in the detection of anticentromere antibodies and anti-DNA. Measurement of ANA in consecutive patients for whom an ANA test was requested showed that, generally, those assays with high sensitivity for detection of SLE had a high false-positive rate, whereas those assays with a low false-positive rate failed to identify some patients with a clinical diagnosis of SLE. Conclusion. There are significant differences in the detection of ANA by immunofluorescence and different ELISA kits. Agreement between different assays is generally marginal. When ordering and interpreting an ANA test, the clinician must be familiar with the specific assay being used to measure ANA and the differences between the various ANA assays.     

Use of a new fluorescence immunoassay to detect anti-dsDNA antibodies is more correlated with disease activity and complement than the ELISA method in SLE patients

To determine whether the serum levels of anti-double strand DNA (anti-dsDNA) autoantibodies detected using a newly developed fluorescence immunoassay (FIA) in patients with systemic lupus erythematosus (SLE) correlated more with clinical parameters, such as SLE disease activity index (SLEDAI), complement and the occurrence of nephritis when compared with traditional enzyme-linked immunosorbent assay (ELISA), we prospectively collected 124 serum samples from 31 patients who had juvenile-onset SLE and were regularly monitored every 2 months at our outpatient clinic. At every visit, clinical manifestations and laboratory parameters were assessed and the SLEDAI was determined. Correlation analyses between the two different measurements of anti-dsDNA antibodies and SLEDAI, serum complement levels and the occurrence of nephritis were performed. The results showed that anti-dsDNA autoantibodies detected using both ELISA and FIA significantly correlated with SLEDAI, and significantly and inversely correlated with the serum levels of C3 and C4. FIA had significantly higher correlation with SLEDAI and C4 than did ELISA. The mean values of anti-dsDNA antibodies detected using FIA in patients with nephritis were significantly higher than in those without nephritis. In contrast, the values of anti-dsDNA antibodies detected using ELISA did not show significant differences between these two groups. We conclude that FIA had better correlation with SLEDAI, C4 and the occurrence of nephritis, and comparable correlations with C3 that were similar to the results found using ELISA. Thus, it is worthwhile developing the FIA method for clinical evaluation of disease activity in SLE patients.     

Nine-year's follow up on the appearance of autoantibodies in a child with idiopathic thrombocytopenic purpura subsequently developing lupus with central nervous system manifestations]

We describe a 23-year-old female who developed SLE 9 years after asymptomatic idiopathic thrombocytopenic purpura (ITP) with positive antinuclear antibody (ANA). Although the platelet count was normal before the onset of SLE, the titer of ANA was gradually increased and also autoantibodies, including antibodies to SS-A/Ro, single-stranded DNA (ss-DNA) and nuclear ribonucleoprotein (RNP) changed to positive. At 23 years of age, the patient was admitted to our hospital because of fever, butterfly rash and polyarthritis. Anti double-strand DNA (ds-DNA) antibody and anti Smith antigen (Sm) antibody were positive and the platelet count and titer of complements were decreased. The patient was diagnosed as SLE and treated with 60 mg/day of prednisolone. Despite steroid therapy, psychiatric symptoms appeared. Additional treatments with steroid pulse therapy and double filtration plasmaphresis resulted in the improvement of SLE including the central nervous system manifestations. This case suggested that increased titer of ANA and the appearance of antibodies to SS-A, ss-DNA, RNP, ds-DNA and Sm in ITP patients predict the development of SLE. Routine checkup of autoantibodies is needed to manage ITP with positive ANA.     

Diagnostic value of combined evaluation of neopterin and anti-DNA antibody levels for assessment of disease activity in systemic lupus erythematosus

OBJECTIVE: The present study was designed to investigate whether the combined evaluation of laboratory tests could improve their diagnostic value. Laboratory parameters of systemic lupus erythematosus (SLE), such as anti-dsDNA, neopterin, soluble IL-2 receptor (sIL-2R), C3, C4, and complement haemolytic activity (CH50), and a logistic model that provides the probable clinical activity (PCA) of a given patient, calculated by stepwise multiple logistic regression analysis from the parameters mentioned above--were evaluated as SLE activation markers. METHODS: Serum samples from 101 patients were assayed by ELISA (neopterin, sIL-2R, anti-dsDNA), radial immunodiffusion (C3, C4) and haemolytic complement assay (CH50). RESULTS: Among the parameters investigated, PCA showed the greatest difference between the values representing active and inactive stages of the disease (p < 0.001), the highest correlation with SLEDAI (p < 0.001) and the highest sensitivity and specificity values (0.91, 0.88, respectively). Moreover, this value of PCA was the most useful in discriminating between active and inactive sample pairs. CONCLUSION: We conclude that PCA is more useful in evaluating SLE activity than the single parameters studied.