ANCA 검사의 임상적 유용성에 관한 재평가

전래희 ( La He Jearn ),김신규 ( Think You Kim ) 대한류마티스학회 2004 대한류마티스학회지 Vol.11 No.1

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. Conclusion: 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.

류마티스 관절염 환자에서 anti-centromere antibody의 임상적 의의

전래희 ( La He Jearn ),김신규 ( Think You Kim ) 대한류마티스학회 2004 대한류마티스학회지 Vol.11 No.2

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. Methods: 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.

항응고제에 따른 HLA-B27 검사를 위한 세포 생존능 보존 기간의 비교

김홍석 ( Hong Seok Kim ),전래희 ( La He Jearn ),김신규 ( Think You Kim ) 대한류마티스학회 2004 대한류마티스학회지 Vol.11 No.3

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 4℃ 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.

한랭글로불린의 조기결과 보고를 위한 연구

김종우 ( Jong Woo Kim ),전래희 ( La He Jearn ),김신규 ( Think You Kim ) 대한류마티스학회 2004 대한류마티스학회지 Vol.11 No.2

Objective: Cryoglobulins are immunoglobulins that tend to form reversible precipitations below 37℃, 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. Methods: 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℃ and 4℃ 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.

류마티스 인자 측정의 가장 우수한 방법은?

민도식 ( Doh Sik Minn ),전래희 ( La He Jearn ),김신규 ( Think You Kim ) 대한류마티스학회 2006 대한류마티스학회지 Vol.13 No.1

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.