BACKGROUND: Measurements of serum anti-thyroglobulin antibody (anti-Tg) and anti-thyroid peroxidase antibody (anti-TPO) are important for the diagnosis of autoimmune thyroid diseases. Although ELISA is most commonly used for the detection of anti-thyroid autoantibodies, other methods like particle agglutination assay (PA) or radioimmunoassay (RIA) are still being used in clinical laboratories. There are few studies about the comparison between PA and ELISA, and we evaluated the validity of these assays in this study. METHODS: We have used three methods, PA (Fujirebio Inc.), ELISA-1 (Zeus Scientific Inc.), and ELISA-2 (Orgentec Diagnostika) for the measurements of titers or concentrations of anti-thyroid autoantibodies. A total of 212 patients belonging to six different disease groups were tested: 40 patients for anti-Tg only, 64 for anti-TPO (or anti-microsome) only, and 108 for both antibodies. All test results were compared with each other in six disease groups. RESULTS: Concordance of positive or negative results was obtained in 78.5-97.3% of the samples tested, and positive rates of three methods were similar in autoimmume thyroid disease group. In the comparable concentration range, the correlation coefficients were 0.328-0.820 between the two ELISAs or between ELISA and PA. CONCLUSIONS: Positive or negative decisions by three assay systems have high concordance rates, and antibody levels measured by three methods correlate well in the comparable concentration range. The ELISA-1 shows less non-specific reactions, better discrimination in low level of autoantibodies, and the highest positive rate in autoimmume thyroid disease group.
Agglutination ; Antibodies ; Autoantibodies ; Discrimination (Psychology) ; Enzyme-Linked Immunosorbent Assay ; Humans ; Peroxidase ; Radioimmunoassay ; Thyroid Diseases

BACKGROUND: The two common serological test methods used for initial diagnosis of acute Mycoplasma pneumoniae (MP) pneumonia are particle agglutination assay (PA) and enzyme immunoassay (EIA). We compared the differences between the two methods and suggest a test method more suitable for clinical laboratories. METHODS: A total of 35 patients (18 adult and 17 pediatric) performed MP specific antibody test using PA (Serodia-Myco II, Fujirebio, Japan) and EIA (Ani Labsystems, Finland) methods. IgM and IgG antibodies were measured separately by EIA method. PA and both IgM and IgG EIA were tested in 26 patients and PA and IgG-EIA were tested in 9 patients. RESULTS: The concordance rates between PA and EIA were 57.7% for IgM and 65.7% for IgG antibodies. Positive PA results showed better agreement with IgG (77.8%) than IgM (38.9%), while negative PA results showed better agreement with IgM (100%) than IgG EIA results (25%). In adult patients, the correlation between PA titers and IgM (r=0.852, P <0.01) and IgG values (r=0.517, P <0.05) were statistically significant. In pediatric patients, the correlation between PA titers and IgG values (r=0.842, P <0.01) was statistically significant. CONCLUSIONS: In this study, we observed that PA and EIA may not be used alternatively. Therefore, we suggest that use of both PA and IgM-EIA will be the optimal choice for laboratories. However, when laboratories are required to select one from PA or EIA, PA may be more useful to diagnose MP infection.
Adult ; Agglutination ; Antibodies ; Humans ; Immunoenzyme Techniques ; Immunoglobulin G ; Immunoglobulin M ; Mycoplasma ; Mycoplasma pneumoniae ; Pneumonia ; Pneumonia, Mycoplasma ; Serologic Tests

BACKGROUND: Many studies have reported the association between several anti-neuronal antibodies and neurologic diseases. However, there is no useful autoantibody screening test for neurologic diseases unlike the antinuclear antibody test for rheumatologic diseases. Hence, we investigated the clinical utility of the autoimmune target (AIT) test as screening test for autoantibodies in neurologic diseases. METHODS: We retrospectively analyzed the results of the AIT test for 375 serum samples of patients diagnosed with several neurologic diseases such as motor neuron disease (MND), amyotrophic lateral sclerosis (ALS), Parkinson's disease (PD), encephalopathy (EC), polyneuropathy (PN), cerebral ischemic attack, encephalitis, myelitis, epilepsy, and stroke. RESULTS: The overall positive rate of the AIT test in aforementioned diseases was 77.9%. The positive rates for MND, ALS, PD, EC, PN, and the others were 81.3%, 83.9%, 84.8%, 59.3%, 73%, and 75%, respectively. CONCLUSIONS: Our results indicate high positive rates in the AIT test. We believe that the AIT test has potential application for autoantibody screening in the neurologic diseases. We look forward to last as the study about relations between the results of the AIT test and the specific antibodies for neurologic diseases.
Amyotrophic Lateral Sclerosis ; Antibodies ; Antibodies, Antinuclear ; Autoantibodies ; Brain Diseases ; Encephalitis ; Epilepsy ; Humans ; Mass Screening ; Motor Neuron Disease ; Myelitis ; Parkinson Disease ; Polyneuropathies ; Retrospective Studies ; Stroke

BACKGROUND: Anti-streptolysin O (ASO) test is usually used to diagnose group A streptococcal infection-related diseases, such as rheumatic fever, reactive arthritis, and various infectious diseases. Despite the recent declining incidence of these diseases, ASO test is still frequently performed as a screening test to diagnose rheumatic diseases. This study re-evaluated the clinical usefulness of ASO test in systemic rheumatic diseases (SRD). METHODS: ASO tests was performed in 825 patients between April and October in 2010. ASO levels were compared between SRD and non-SRD groups of patients. The results of ASO, C-reactive protein (CRP), and rheumatoid factor (RF) were compared among 6 subgroups of SRD: rheumatoid arthritis, systemic lupus erythematosus, ankylosing spondylitis, Behcet disease, Sjogren's syndrome and others. RESULTS: Positive results in ASO test (>200 IU/mL) were observed in 15.3% (126/825) of the patients tested. None of the ASO positive patients was, however, diagnosed with rheumatic fever or reactive arthritis. There were no statistically significant differences in the mean value (P=0.688) or positive rate (P=0.835) of ASO test between SRD and non-SRD groups. Positive rates of ASO test were also not statistically significant different among six subgroups of SRD patients (all P>0.05), whereas those of CRP and RF tests were significantly different. CONCLUSIONS: The usefulness of ASO test is very low for diagnosing SRD, although it is frequently carried out as a screening test. We suggest that ASO test must be performed selectively when diseases from group A streptococcal infection are suspected.
Arthritis, Reactive ; Arthritis, Rheumatoid ; Behcet Syndrome ; C-Reactive Protein ; Communicable Diseases ; Humans ; Incidence ; Lupus Erythematosus, Systemic ; Mass Screening ; Rheumatic Diseases ; Rheumatic Fever ; Rheumatoid Factor ; Sjogren's Syndrome ; Spondylitis, Ankylosing ; Streptococcal Infections

No abstract available.
Reticulin ; Autoantibodies ; Collagen ; Neoplasms ; Fluorescent Antibody Technique, Indirect ; Neoplasms, Second Primary ; Antibodies, Antinuclear ; Adenocarcinoma ; Carcinoma, Transitional Cell ; Urinary Bladder Neoplasms

No abstract available.
Arthritis, Rheumatoid ; Centromere ; Humans

BACKGROUND: Autoantibodies have been detected in patients with psychiatric disorders. However, there is no standard test for the detection of these autoantibodies. In this study, we analyzed autoimmune target (AIT) test results in patients with psychiatric disorders and investigated the clinical utility of the AIT test for psychiatric disorders. METHODS: We retrospectively analyzed data from patients diagnosed with psychiatric disorders between August 1995 and May 2015. Of these, 100 patients assessed using the AIT test were enrolled in this study. Data regarding positive rates, immunofluorescent patterns of AIT results, and the presence of autoimmune diseases in patients with psychiatric disorders were retrospectively collected and analyzed. RESULTS: The autoantibody-positive rate was high in patients with psychiatric disorders (70.0%, 70/100). The positive rates in patients with schizophrenia, depressive disorders, bipolar and related disorders, adjustment disorders, anxiety disorders, and others were 82.9%, 64.7%, 88.9%, 57.1%, 66.7%, and 53.8%, respectively. The most frequent pattern of immunofluorescence was a speckled pattern in 30 cases, followed by microtubule organizing center with microtubule (MTOC-MT) in 17 cases. Twenty-one patients were diagnosed with autoimmune diseases. CONCLUSIONS: In this study, the incidence of autoantibodies was high in patients with psychiatric disorders not specific to schizophrenia. This suggests that the AIT test may therefore have the potential to be a screening test for psychiatric disorders. Further, additional AIT tests in patients with psychiatric disorders may help to clarify the relationships between psychiatric disorders and autoimmune disease.
Adjustment Disorders ; Anxiety Disorders ; Autoantibodies ; Autoimmune Diseases ; Bipolar and Related Disorders ; Depressive Disorder ; Fluorescent Antibody Technique ; Humans ; Incidence ; Mass Screening ; Microtubule-Organizing Center ; Microtubules ; Retrospective Studies ; Schizophrenia

OBJECTIVE: Anti-centromere antibody (ACA) is known to be specific for CREST syndrome, but individual studies showed variations in its distribution among related diseases. According to the authors'study on 56 ACA positive patients, 37 patients were known to have rheumatoid arthritis (RA). As a consequence, the authors studied the clinical significance of ACA positive RA patients. MEHTODS: Specific clinical findings, radiologic studies, and laboratory data were investigated on 72 ACA positive and on 50 ACA negative RA patients. ACA tests were performed by indirect immunoflourescence assay with IT-1 cell line using IT-AIT kit (ImmunoThink(r), Korea) RESULTS: No specific differences were noted between the ACA positive and the negative group of RA. However, there were a few notable findings between the low titer and the high titer group of ACA positive RA. In comparison with the low titer group, the high titer group showed lesser disease activity, more cases of seronegative RA (39.2%<4.8%), fewer radiologic evidences (45.1%<71.4%), more cases accompanied with Raynaud's phenomenon (15.7%>4.8%) and thyroid diseases (11.8%>0%). They generally showed atypical RA patterns and the antibodies tend to remain at high titer state. CONCLUSION: Since the high titer ACA group of RA patients showed specific clinical findings, it is thought to be necessary to classify such group into a new subset of RA. And such classification would be helpful in diagnosing some atypical forms of RA patients. More studies on these new types of patients as well as their prognoses should be investigated in the future.
Antibodies ; Arthritis, Rheumatoid* ; Cell Line ; Classification ; CREST Syndrome ; Humans ; Prognosis ; Thyroid Diseases

OBJECTIVE: Cryoglobulins are immunoglobulins that tend to form reversible precipitations below 37degrees C, well known to be associated with various diseases such as autoimmune diseases, hematologic malignancies, chronic infections and renal diseases. In many cases, low amounts of cryoglobulins take a few days to be precipitated. In this study, we compared cryoglobulin early screening test with conventional method to evaluate its clinical efficacy. MEHTODS: 28 patients who showed cryoglobulinemia were selected and the time it took for visibly detecting the existence of cryoglobulin were recorded. Sera of cryoglobulinemiemic patients (n=19) and of control group (n=14) kept in two conditions of 37 degrees C and 4 degrees C for 1 hour and were then measured for delta optical density (DOD). RESULTS: In the cryoglobulin early screening test using the test tube, the median and range of the DOD for cryoglobulinemic patient group was 0.50 (0.17~0.99) while it was 0.18 (0.02~0.50) for the control group. The results showed statistically significant difference (p=0.001). In another method of using the microplate, there was no statistical significance between disease and control group. The area under the curve for test tube method was 0.857. The sensitivity and specificity were 89.5% and 71.4% respectively (cut-off value=0.23). CONCLUSION: Cryoglobulin early screening test provides the results within 2 hours and we thought this feature could give clinicians some helpful informations. More studies are needed in the future for increasing the sensitivity and specificity of this test.
Autoimmune Diseases ; Cryoglobulinemia ; Cryoglobulins ; Hematologic Neoplasms ; Humans ; Immunoglobulins ; Mass Screening* ; Sensitivity and Specificity

OBJECTIVE: Rheumatoid factor (RF) is used as one of the criteria for the diagnosis of rheumatoid arthritis (RA). Nephelometers are widely used in laboratories to quantitatively measure RF. In nephelometric ways of measurement, there are endpoint nephelometry and rate nephelometry. BN II System (BN II) (Dade Behring Marburg GmbH, USA) is a well known endpoint nephelometer while IMMAGE System (IMMAGE) (Beckman Coulter, USA) is a well known rate nephelometer. We compared these two automatic nephelometric analyzers to evaluate which method shows the best results. METHODS: We measured RF (n=195) using the two machines. We evaluated the correlation between BN II and IMMAGE. We compared the results of BN II with those of IMMAGE in terms of interference and clinical usefulness. RESULTS: The correlation coefficient (r) of RF was 0.9310 (p<0.0001). We could not find any significant interference for BN II with high concentration of triglyceride or bilirubin, but IMMAGE showed significant interferences with high concentrations of triglyceride and bilirubin. The sensitivity and specificity of BN II for the diagnosis of RA were 90.3% and 82.4%. Those of IMMAGE were 86.1% and 74.5%. CONCLUSION: BN II was enough to satisfy the analytical features and it showed better results than IMMAGE. We expect BN II, the endpoint nephelometer, to be the best equipment in measuring RF for diagnosis of RA.
Arthritis, Rheumatoid ; Bilirubin ; Diagnosis ; Nephelometry and Turbidimetry ; Rheumatoid Factor* ; Sensitivity and Specificity ; Triglycerides