Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0409974 (lupus)
 22,386 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Congenital protein S (PS) deficiency is associated with increased risk of venous thrombosis. To investigate the possibility of automating PS testing with decreased turnaround time, a clotting-based functional protein S assay was evaluated and compared to an antigenic method. Samples were collected from 126 patients within 5 days of their first acute cerebral infarction, from 62 controls and from 47 consecutive samples for thrombophilia investigation. The normal range for the clotting-based kit, calculated from the results of 20 healthy controls, was 62-136% (mean +/- 2 SD). Intra- and inter-assay co-efficients of variation were < 3.0 and 10.0% respectively. There was no significant correlation between the two methods (r = 0.30, P > 0.05). Two patients had low PS antigen results with normal functional levels. Both techniques were used to compare a further group of 53 patients with defined abnormalities which included nine antigenic protein S deficiencies, five protein C deficient patients, 10 patients with a lupus anticoagulant (LA), 17 Factor V Leiden (FVL) heterozygotes, two FVL homozygotes and 10 patients on therapeutic levels of heparin. In this group we found that four of nine antigenic PS deficient patients had normal functional PS levels. The test was susceptible to the FVL mutation with four of 17 FVL heterozygotes and both of two FVL homozygotes giving low levels. One of five protein C-deficient patients also had a low functional PS result with a normal antigenic level. Normal results were obtained by both methods for all of the LA and patients on therapeutic heparin. We concluded that the automated protein S clotting assay was rapid and simple to perform but appeared to be influenced by factors other than PS deficiency. Results need to be interpreted with caution but may be useful as part of a full thrombophilia investigation.
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PMID:Detection of protein S deficiency: a new functional assay compared to an antigenic technique. 1084 Aug 27

The antinuclear antibodies (ANA) test has been a cornerstone of the evaluation of connective tissue disease. The aim of this study was to investigate the diagnostic value of the ANA test in pleural or pericardial effusions of unknown causes. Over a 3-yr period, a total of 126 pleural fluid and 30 pericardial fluid samples were analysed. ANA tests were performed using a commercially available kit. The ANA kit used an indirect immunofluorescent antibody method with a human epithelial (HEP-2) cell line as substrate. Patients with high fluid ANA titre (>1:160) received a second aspiration 2 weeks after the initial aspiration if diagnosis was not confirmed. ANA results were positive in 39 pleural and 10 pericardial fluid samples. All but one of the effusions with positive ANA testing were exudative. Eleven pleural or pericardial effusions due to active systematic lupus erythematosus were identified and all had high ANA titres (1:160) with various staining patterns. Thirty-eight of 145 patients (26%) with effusions of nonlupus aetiologies had positive ANA testing in pleural or pericardial fluid. Thirteen of these 38 patients had high ANA titre. Malignant or paramalignant effusions constituted 11 of the 13 samples. In conclusion, although a negative antinuclear antibodies test makes a diagnosis of lupus serositis unlikely, high antinuclear antibodies titres in pleural or pericardial fluid are not diagnostic of lupus serositis even when as high as 1:5,120. An unexplained high antinuclear antibodies titre in pleural or pericardial effusion warrants search for malignancy.
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PMID:Serial antinuclear antibodies titre in pleural and pericardial fluid. 1088 31

Three commercial dilute Russell's viper venom time (DRVVT) kits were evaluated at four UK centres experienced at performing lupus anticoagulant (LA) tests. Each centre established a normal reference range for the DRVVT ratio calculated against local pooled normal plasma from 20 healthy normal subjects. Plasma from LA-positive patients and LA-negative thrombophilia patients was also tested. DRVVT ratios and the degree of correction were assessed in a variety of ways to reflect not only the UK national Guidelines, but also the manufacturers' recommendations. The reference range data showed a normal distribution in each case, but considerable variation in the mean and SD between the centres and reagents, with the mean +2SD value ranging from 1.06 to 1.19. The use of an arbitrary DRVVT ratio of < 1.1 as the cut-off value for normality, which is applied in many laboratories, is therefore inappropriate. Although no single kit had a clear overall advantage in terms of sensitivity and specificity, the way in which the screen and confirmation data were analysed had a major impact on the interpretation of the results. A data analysis method employing a mean plus two standard deviations (SDs) cut-off for normality, and judgement regarding confirmation of LA based on a percentage correction of DRVVT ratio, was the simplest and most consistent, with overall sensitivity and specificity values of 81% and 94%, respectively, for uncomplicated LA-positive and LA-negative thrombophilia samples. We conclude that the 1991 BSCH Guidelines are in need of revision, each laboratory should establish its own normal reference range for the DRVVT ratio and a common method should be used for calculating the degree of correction with confirmation reagents, so that LA results can be correctly interpreted between laboratories. Standardizing DRVVT interpretation in this way should improve the consistency of LA detection.
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PMID:The importance of locally derived reference ranges and standardized calculation of dilute Russell's viper venom time results in screening for lupus anticoagulant. 1116 66

The aim of this study was to examine whether the clinical features of antiphospholipid antibody syndrome are associated with anti-cardiolipin and anti-beta2 glycoprotein I antibodies in Indian patients with SLE. Seventy-six patients (71 females), who fulfilled 1982 ACR criteria for SLE, were prospectively studied for the clinical features of antiphospholipid antibody syndrome (APS), and their sera were analysed for the presence of IgG/IgM/IgA anti-cardiolipin antibodies (aCL) by an in-house ELISA and, in 65 of them, for the presence of IgG anti-beta2 glycoprotein I antibodies (anti-beta2 GPI) by a commercial kit. Thirty-nine (51%) patients were positive for aCL, all of which were positive for IgG aCL, either alone (79.6%) or along with IgM and/or IgA. Twenty-seven (69.3%) out of 39 aCL-positive and seven (26.9%) out of 26 aCL-negative sera were positive for IgG antibodies to beta2 GPI. There was a significant correlation (r = 0.66, P < 0.05) between the levels of aCL and anti-beta2 GPI antibodies. Forty-one patients had features of definite or suggestive APS. Thrombocytopenia, recurrent pregnancy loss and CNS manifestations (seizures eight, infarct one) were seen in 20, 13 and nine patients, respectively. Thrombosis of the peripheral vessels was seen in only one patient. Only the presence of seizures was significantly associated with the presence of aCL and anti-beta2 GPI antibodies (P < 0.05). The characteristic association of definite APS (recurrent pregnancy loss and arterial/venous thrombosis) was lacking.
Lupus 2001
PMID:Anti-cardiolipin and anti-beta2 glycoprotein I antibodies in Indian patients with systemic lupus erythematosus: association with the presence of seizures. 1124 9

Several methods are now available for the laboratory assessment of activated protein C resistance (APCR). In this study, we evaluated two activated partial thromboplastin time-based assays [Coatest activated protein C (APC) and Diagen protein C activator (PCA)], with and without predilution of test plasma in factor V-deficient plasma (FVdp) and an amidolytic assay (Immuno Ltd, Vienna, Austria). Testing plasmas from normal volunteers who had received 1-deamino-8-D-arginine vasopressin (DDAVP) also assessed the effect of elevated factor VIII on APCR. In the unmodified clotting tests, the Coatest kit gave overlapping results for normal and heterozygous FV:Q506 samples; some FV:Q506 samples on oral anticoagulant therapy (OAT) were misclassified as normal, and some normal samples with high factor VIII levels would be classified as APC resistant. The unmodified Diagen kit correctly classified these three types of sample, but had the disadvantage that prolonged PCA clotting times gave serious problems with instrument end-point detection. Both kits modified by diluting the samples in FVdp correctly classified all the samples, as well as samples from patients with lupus anticoagulant (LA) and patients receiving heparin. The Immunochrom kit correctly classified the normal and FV:Q506 samples, but would have misclassified most normal persons on OAT as well as some patients with LA or receiving heparin therapy as APC resistant.
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PMID:The impact of oral anticoagulant therapy, factor VIII level and quality of factor V-deficient plasma on three commercial methods for activated protein C resistance. 1141 31

The TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling) technique has been described as sensitive method of labeling apoptotic nuclei in tissues, which preferentially stains apoptotic strand breaks. In the current study, three commercially available TUNEL kits for paraffin-embedded and cryostat tissues were tested to optimize this method for the studies on human skin. The investigation included normal skin (n = 10), atopic eczema (n = 4), basal cell carcinoma (n = 5), and lupus erythematosus (LE) (n = 31) sections. Additionally, the expression of certain apoptotic markers (Fas antigen and Bcl-2 protein) was studied immunohistologically on normal and LE skin. During TUNEL labeling according to the manufacturers' protocols, abnormally high background and nonspecific staining were found in all skin sections. The manipulation with the pretreatment time and, in particular, the introduction of an additional step (terminating the labeling reaction by inhibiting the terminal deoxynucleotidyl transferase activity) in two kits led to a remarkable improvement in their performance. The conclusions are that it is generally difficult to establish a functionally specific TUNEL technique for skin sections and that the choice of a kit is absolutely crucial for obtaining reliable results. Considering the extent to which the apoptosis research has been carried out recently, it is advisable to remain critical in evaluating the results. Further, it is necessary to combine the TUNEL technique with the investigation of other apoptotic markers.
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PMID:How specific is the TUNEL reaction? An account of a histochemical study on human skin. 1197 72

Although the importance of the anticardiolipin test in diagnosis of antiphospholipid syndrome (APS) is widely accepted, there remains much misunderstanding about the strengths and weaknesses of this assay. Several disorders result in formation of low levels of the antibody, hence the anticardiolipin test is not specific when results are low positive. In general, the higher the anticardiolipin level the greater the likelihood of a diagnosis of APS. Hence there have been numerous efforts to enable reproducible measurement of anticardiolipin levels. Standard calibrators were introduced to construct calibration curves from which levels of unknown samples can be derived. Those standard calibrators were made by mixing varying quantities of high positive with normal sera. More recently, calibrators derived from monoclonal anticardiolipin antibodies have been introduced. There are advantages and disadvantages with both types of calibrators. Determination of a precise and reproducible anticardiolipin level is difficult, whatever the calibrators used, because the assay is dependent on several variable components, any of which may fail on any given day. Utilization of a semi-quantitative measure (low, medium, high) may suffice in most clinical settings and would be less subject to error. Validated ELISA kits may offer greater reproducibility, since there is less variability than bench assays set up in very different laboratories. Whether using a kit or a bench assay, meticulous attention to detail offers the best opportunity for precision and reproducibility.
Lupus 2002
PMID:Revisiting the anticardiolipin test and its standardization. 1209 May 60

Hyperprolactinemia without clinical manifestations has been reported in some patients with systemic lupus erythematosus (SLE) because an increase of prolactin (PRL) is produced due to the BIG/BIG molecular variant (molecular variant < 150 kD). This research project aimed to determine levels of PRL: its bioactive form, the little nonglycosylated form (NGPRL) and variants with decreased bioactivity such as the BIG/BIG and the little glycosylated (GPRL), in 29 women and five men with SLE. PRL was assayed by IRMA with a kit from Immunotech Laboratory, the BIG/BIG form by precipitation with polyethyleneglycol 6000, and the NGPRL and GPRL by chromatography on Concanavalin-A- Sepharose. Increased PRL was detected in seven patients (20.6%) of whom three had increased BIG/BIG, six had increased GPRL and only four had increased NGPRL. The three cases with increased BIG/BIG were contrasted by chromatography on Sephadex G-100. No increased PRL or any of the other variants assayed were found in men. Results were similar when PRL was evaluated in the same blood samples by a different IRMA (DPC Laboratory). The etiology of the hyperprolactinemia in some of these patients is unknown, but their lack of symptoms (galactorrhea or amenorrhea) could be due to the BIG/BIG forms and basically to the glycosylation of the hormone. As for the relation between PRL and SLE activity, we found that hyperprolactinemic patients were younger, had a shorter history of illness, although it was not statistically significant, and a higher SLEDAI score. This would indicate a relation between hyperprolactinemia and lupus activity. The patients with increased BIG/BIG form also had a very active illness at the time of the study.
Lupus 2004
PMID:Analysis of molecular heterogeneity of prolactin in human systemic lupus erythematosus. 1546 86

In our study we have investigated the presence of apoptotic bodies, soluble FAS receptor and TNF (tumor necrosis factor) in three clinical forms of lupus erythematosus. Determinations were performed in attack period of: systemic lupus erythematosus (SLE) for 20 patients, 20 patients with subacute cutaneous lupus erythematosus (SCLE), 20 patients with chronic discoid lupus erythematosus (DLE). Determinations were performed by ELISA (for apoptotic bodies, kit Boehringer, normal values 400-800 mU), (for sFAS, kit R&D Systems, normal values 4500-17000 pg/ml) (for TNF, ELISA kit R&D Systems, normal values 0.4-3.6 pg/ml). Results in SLE: apoptotic bodies were increased in 16 cases (980-1030); sFAS in 18 cases (17000-24000 pg/ml) TNF was increased in all 20 cases (40-140 pg/ml). In SCLE with multiple cutaneous lesions and without internal organs disturbance the apoptotic bodies were increased in 10 cases (960-1030 pg/ml), sFAS in 9 cases (17000-22000 pg/ml), and TNF alpha in 9 cases. In DLE, apoptotic bodies were increased in 2 patients (980-1010 pg/ml), sFAS in 3 patients (17000-20000 pg/ml) and TNF in 2 patients (20-40 pg/mil). Investigated values were slightly correlated with immune parameters (anti dsDNA antibodies), but they were correlated with the presence of renal disturbances or extension of cutaneous lesions. We consider that the presence of increased apoptotic bodies as a result of peripheral mononuclear cells apoptosis appear as a nauto-limiting mechanism in a pathological immune response. The increase of sFAS in lupus patients serum might be interpreted as an alteration of apoptosis respectively a deficit in apoptosis which has as a first consequence the persistence of B and T lymphocytes, activated, in the pathogen immune response.
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PMID:Serological levels of apoptotic bodies, sFAS and TNF in lupus erythematosus. 1552 75

Apolipoprotein H (apoH) is considered to be a necessary cofactor for the binding of certain antiphospholipid antibodies to anionic phospholipids. Some apoH-dependent antiphospholipid antibodies also exert lupus anticoagulant (LA) activity, which seems to depend on antiphospholipid antibody epitope specificity. The aim of this study was to evaluate whether the presence of less frequent apoH alleles may induce structural or conformational changes in these "LA-dependent" regions that may initiate more frequent autoimmune responses in subjects. We selected patients with confirmed LA activity and none or low titers of anticardiolipin antibodies that had been sent to the laboratory for routine antiphospholipid antibody determination. Many of them had some clinical manifestation of antiphospholipid syndrome. Antibodies to apoH were determined with a commercially available anticardiolipin/apoH ELISA kit. ApoH protein polymorphism (apoH phenotype) was demonstrated by isoelectric focusing and immunoblotting. Our results showed that 47/74 (63.5%) of our selected LA-positive patients also had elevated apoH-dependent antiphospholipid antibody titers. These results point to two subgroups of patients according to the LA potency of apoH-dependent antibodies. A strong positive correlation (non-linear or linear) for apoH-dependent antibody titers and LA activity was observed in both subgroups of patients. In this study, we did not find significant differences in the distribution of apoH phenotypes among control subjects and patients with apoH-dependent/LA-positive auto- antibodies.
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PMID:Apolipoprotein H (apoH)-dependent autoantibodies and apoH protein polymorphism in selected patients showing lupus anticoagulant activity. 1565 37


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