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: 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

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: 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

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: HLA-B27 test require at least 80% of viable cells. So the procedures require immediate processing of the blood samples. To increase the efficiency and the cost-effectiveness of the laboratory, longer maintenance of cell viability is requested. For this purpose, we compared the cell viability of blood samples collected in heparin tubes with those collected in ACD tubes. Our aim was to determine whether the length of storage that could maintain adequate cell viability for HLA-B27 testing depends on the anticoagulants in the storage tube and to ascertain the qualified HLA-B27 results after several days of storage. METHODS: We collected 15 blood samples in ACD and heparin tubes. The samples were stored at 4oC for 6 days and after which, 2 mL of the sample was used to confirm the viability of lymphocytes every 24 hours for 5 days. For evaluating the reproducibility, the HLA-B27 test was performed at the day of sampling and after 6 days of refrigeration. RESULTS: There was no difference in cell viability between ACD and heparin until the sixth day, but a statistically difference was observed from the seventh day (p=0.004). The HLA-B27 test showed no different results even after 6 days of storage. CONCLUSION: We suggest that the heparin tubes have a same storage benefit as the ACD tubes of blood for HLA-B27 testing for less than a week. This can affect more economic and efficient laboratory management for HLA-B27 testing.
Anticoagulants* ; Cell Survival* ; Heparin ; HLA-B27 Antigen* ; Lymphocytes ; Refrigeration

OBJECTIVE: Antineutrophil cytoplasmic antibody (ANCA) is known to be associated with vasculitides. But recently ANCA has been reported in some chronic inflammatory diseases regardless of vasculitic condition. Although the incidence of vasculitis was low in Korea, we occasionally encounter patients with positive ANCA. And it was doubtful whether ANCA positivity of reports, in time that ANCA test was introduced in Korea, was true. So this study aimed to reevaluate the clinical utility of ANCA with the modern stabilized substrate. METHODS: 162 patients with positive ANCA from Jan. 2002 to Jan. 2003 were investigated. ANCA was tested by indirect immunofluorescence assay using ALCA kit (ImmunoThink(R), Korea). RESULTS: Of 162 patients, 158 were P-ANCA positive, 2 were C-ANCA positive and 2 were atypical C-ANCA positive. Most of the ANCA positive patients had chronic inflammatory diseases-129 patients (79.6%) with rheumatoid arthritis (RA), 4 (2.5%) with lupus and 4 (2.5%) with ulcerative colitis. Only 3 patients (1.9%) had vasculitides and the remaining seventeen patients had other diseases. Among the RA patients with ANCA, 27.9% were seronegative RA. CONCLUSIONS: In order to increase the clinical applicability of ANCA test in diagnosing vasculitides, it is essential to decrease the false positivity by using stabilized substrate and by adapting professional interpretation from experts. And our results suggest that ANCA test can be useful for diagnosing chronic inflammatory diseases such as rheumatic diseases (especially RA) along with vasculitides in Korea. Further study will be needed for the diagnostic utility of ANCA in RA.
Antibodies, Antineutrophil Cytoplasmic* ; Arthritis, Rheumatoid ; Colitis, Ulcerative ; Fluorescent Antibody Technique, Indirect ; Humans ; Incidence ; Korea ; Rheumatic Diseases ; Vasculitis

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