Performance Validation of Three Scoring Systems for the Prediction of Thrombotic Microangiopathy Due to Severe ADAMTS13 Deficiency and the Response to Therapeutic Plasma Exchange: First Study in Korea

Background@#The BENTLEY score (B-S), French thrombotic microangiopathy (TMA) Reference Center score (FTMA-S), and PLASMIC score (PLASMIC-S) have been developed for TMA diagnostic prediction. We retrospectively validated their predictive performances in patients with severe (<10%) disintegrin and metalloprotease with thrombospondin type 1 motif, member 13 (ADAMTS13) deficiency in terms of the risk of TMA and response to therapeutic plasma exchange (TPE). @*Methods@#The predictive performances of the three scoring systems were compared in 145 patients with suspected TMA who underwent ADAMTS13 activity tests between January 2014 and September 2022. The response to TPE and mortality in TMA-positive patients were compared after risk stratification, using the Mann–Whitney U and Fisher’s exact tests. @*Results@#The PLASMIC-S, FTMA-S, and B-S showed area under the curve values of 0.820, 0.636, and 0.513, respectively, for predicting TMA positivity in high-risk patients. The PLASMIC-S showed higher sensitivity (81.8%), negative predictive value (91.2%), positive predictive value (PPV; 66.7%), and accuracy (82.1%) than the FTMA-S (72.7%, 82.1%, 41.0%, and 60.0%, respectively) and B-S (4.6%, 70.2%, 50.0%, and 69.7%, respectively). The PLASMIC-S also showed higher specificity than the FTMA-S (82.2% vs. 54.5%). The modified PLASMIC-S, including lactate dehydrogenase/upper limit of normal ratios, increased the specificity, PPV, and accuracy to 97.0%, 92.3%, and 92.4%, respectively. In TMA-positive patients, high risk assessed by the PLASMIC-S predicted higher platelet recovery rates and less TPE sessions required for recovery than for those assessed at low-to-intermediate risk. @*Conclusions@#PLASMIC-S is the preferred scoring system for detecting patients with TMA positivity and for prognosis before confirmation of ADAMTS13 activity.

Bone marrow metastasis of small cell lung carcinoma with spontaneous tumor lysis syndrome without hepatic metastasis at diagnosis: first case report in Korea and review of literature

No abstract available.

High-grade nodal marginal zone lymphoma with diffuse bone marrow involvement and IgM-type monoclonal paraproteinemia: a case report and review of the literature

No abstract available.

Low-grade follicular lymphoma involvement of the bone marrow with a mixed paratrabecular, diffuse, and massive pattern expressing typical mantle cell lymphoma immunophenotype CD23−/FMC7+: a case report

No abstract available.

Morphometric Differences of Distal Femoral Cut Surface between Korean Male and Female in Total Knee Arthroplasty / 대한정형외과학회잡지

PURPOSE: The purpose of this study is to evaluate the morphometric differences of distal femoral cut surface between Korean males and females in total knee arthroplasty. MATERIALS AND METHODS: A total of 696 patients (1,008 knees: male 92, female 916) who underwent TKA using NexGen® legacy posteriorstabilized (LPS) (605 knees: male 41, female 564) and PS ADVANCE® medical pivot knee (MPK) (403 knees: male 51, female 352) implants were analyzed prospectively. After distal femoral resection, the mediolateral width (ML) was measured at four points (anterior [Ant], distal anterior [DA], distal posterior [DP], and posterior [Post]) and compared with the ML width of the implant respectively. The aspect ratio (AR=ML/anteroposterior width) and width ratio (WR=Ant ML/DP ML) were calculated. Differences in AR, WR, and fitness between male and female were analyzed. RESULTS: The AR of males was larger than that of females for both LPS and MPK; however, no differences in the WR were observed between males and females. The WR in MPK was larger than that in LPS. For both LPS and MPK, females showed greater anatomical fitness than males, and males had relatively greater incidence of undersize than females. For MPK, there were relatively more cases of overhang in Ant and DA cut surface. These results were consistent with the fact that the WR of implant in MPK was larger than that in LPS. CONCLUSION: Korean males tend to have larger AR and less anatomical fitness of the femoral component than females because of undersize. No difference in WR was observed between Korean males and females. However, the cut surfaces as well as femoral implant of MPK had larger WR than those of LPS. MPK has more overhang on the anterior cut surface than LPS, due to a wider Ant flange (larger WR) of the implant.

Total Knee Arthroplasty Using a Posterior Cruciate Ligament Sacrificing Medial Pivot Knee: Minimum 5-year Follow-up Results

PURPOSE: To evaluate minimum 5-year follow-up clinical and radiological results of total knee arthroplasty (TKA) using a posterior cruciate ligament sacrificing (PS), non-substituting Advance Medial Pivot Knee. MATERIALS AND METHODS: One hundred and twenty knees in 80 patients who could be followed up for more than 5 years after TKA using the PS Advance Medial Pivot Knee were evaluated retrospectively. The evaluations included the preoperative and postoperative range of motion (ROM), tibiofemoral angle, Knee Society (KS) knee and function scores, and Western Ontario and McMaster Universities Arthritis Index (WOMAC) score. The Kaplan-Meier method was used for survival analysis. RESULTS: The ROM increased from a preoperative mean flexion contracture of 7.6degrees and further flexion of 115.1degrees to a postoperative mean flexion contracture of 1.5degrees and further flexion of 120.5degrees. The tibiofemoral angle was changed from 4.6degrees varus preoperatively to 5.8degrees valgus postoperatively. The KS knee and function scores as well as WOMAC score significantly improved after surgery (p<0.05). Complications developed in 4 cases (3.3%): 2 cases of periprosthetic patellar fracture (1.7%) and 2 cases of aseptic loosening (1.7%). The seven-year survival rate was 98.1% in the Kaplan-Meier survival analysis. CONCLUSIONS: The minimum 5-year follow-up results of TKA using the PS Medial Pivot Knee were satisfactory.

The Combination of Real-Time PCR and HPLC for the Identification of Non-Tuberculous Mycobacteria

We used HPLC and AdvanSure real-time PCR (LG Life Sciences, Korea) to retrospectively analyze non-tuberculous mycobacteria (NTM) in 133 clinical specimens. The specimens were culture-positive for NTM and the HPLC method identified 130 strains of mycobacteria from the cultures (97.7%) at the species level. Among the isolates, 48 Mycobacterium. kansasii (36.1%), 39 M. intracellulare (29.3%), 17 M. avium (12.8%), 16 M. abscessus (12.0%), 6 M. fortuitum (4.5%), 2 M. szulgai (1.5%), 2 M. gordonae (1.5%), and 3 unclassified NTM strains (2.3%) were identified. The real-time PCR assay identified 60 NTM-positive specimens (45.1%), 65 negative specimens (48.9%), and 8 M. tuberculosis (TB)-positive specimens (6.0%). The real-time PCR assay is advantageous because of its rapid identification of NTM. However, in our study, the real-time PCR assay showed relatively low sensitivity (45.1%) when using direct specimens including sputum and bronchoalveolar lavage (BAL) fluid. HPLC is useful as it discriminates NTM at the species level, although it is time-consuming and requires specific equipment and technical expertise. A combination of both methods will be helpful for the rapid and accurate identification of mycobacteria in clinical laboratories.

Performance Evaluation of 3 Kinds of HBsAg Qualitative Assays and 2 Kinds of Quantitative Assays

BACKGROUND: Currently used techniques for quantitation of HBsAg often yield discordant results; therefore, development of quantitation techniques that can detect HBsAg with high accuracy has become very important. Recent advances have led to the development of several HBsAg detection systems. Here, we evaluated the performance of 3 newly developed detection systems, which can detect HBsAg both qualitatively and quantitavely, and determined the concordance among their results. METHODS: Four hundred and thirty two samples assigned to 4 groups-patient group, dilution group, weakly reactive group, and linearity group- were subjected to qualitative and quantitative detection of HBsAg by using the 3 systems developed by 3 major manufacturers; Abbott Architect, Roche E170 and Siemens Centaur XP. RESULTS: The results for the qualitative analyses were closely concordant among the three systems (98.3%) for all 432 samples. In 123 samples that were determined as HBsAg-negative, E170 (76%) distributed frequently at the upper half level (0.5-1.0) of negative reference range, compared with Architect (11%) and Centaur XP (22%). In particular, in 65 samples that were diluted from the strongly positive samples to obtain weakly positive samples, the average index values obtained using Architect (3.6 S/CO), E170 (4.2 COI) and Centaur XP (11.4 index value) differed significantly (P<0.0001). In the antiviral treatment group and the post-liver transplantation group, no inconsistency was observed among the results of the qualitative and quantitative assays. In the 18-fold serially diluted samples, no linearity was observed. CONCLUSIONS: Because of the possibility of false-positive detection in the HBsAg-negative samples, regular management of equipment and appropriate selection of reagents are very important. In weakly positive samples, quantitative assay has not to be replaced for qualitative assay. Therefore, the qualitative assays should be used for screening the samples, whereas the quantitative assays should be used for monitoring the Hepatitis B virus (HBV) load in the samples determined as HBsAg-positive. The qualitative index value should not be interpreted as a quantitative measure of HBV load.

Performance Evaluation of Immunoassay Detection of HBsAg Mutants and Their Clinical Significance in the High Risk Groups

BACKGROUND: False negative results have been reported in the immunodetection of hepatitis B virus (HBV) because of the existence of the various mutants of the virus, causing most suppliers to try to develop superior reagents by using highly sensitive and specific monoclonal or polyclonal antibodies. In this study, we evaluated the effectiveness of 3 newly developed reagents by major manufacturers by adopting automated methods with increased sensitivity and specificity in the detection and discrimination of native and recombinant mutant antigens. METHODS: We analyzed samples confirmed positive for hepatitis B surface antigen (HBsAg), high-risk samples from chronic hepatitis patients treated with antiviral agents, and samples from patients who had undergone liver transplantation and were treated with high-dose hepatitis B immunoglobulin (HBIG) by using reagents and systems newly developed by Abbott Laboratories (USA), Roche Diagnostics (Germany), and Siemens Healthcare Diagnostics (USA). Recombinant sample panels from these manufacturers with low and high concentrations were also analyzed for comparing the 3 reagents. RESULTS: There were no discrepant results among the various selected patient groups; however, for the recombinant mutant panels, all of the 3 reagents showed highly positive detection rates for their corresponding mutant panels, but showed relatively discrepant mutant detection rates when cross-tested with the other mutant panels. Detection rates of the HBsAg mutant panels were higher at a higher concentration of the mutant samples, but were lower for the same mutant receptor sites at a lower concentration. CONCLUSIONS: The 3 major detection methods seem to recognize the major native mutants commonly encountered in clinical practice. However, in the case of recombinant mutants, we believe that our data are not to be interpreted as a reference standard for any reagent, because the results can only be validated for the reagents' corresponding mutant panels; such results tend to be mutually exclusive, and the enough concentration of mutants was required to be adjusted for a comparative analysis.

Lung Infection Caused by Mycobacterium riyadhense Confused with Mycobacterium tuberculosis: The First Case in Korea

A slowly growing, non-chromogenic mycobacterial strain was isolated from sputum and bronchial lavage fluid samples of a patient presenting with productive cough, blood-tinged sputum, low-grade fever, and weakness. A positive acid-fast bacilli sputum smear result prompted the initiation of an anti-tuberculosis regimen. Multiplex real-time PCR showed a negative result for Mycobacterium tuberculosis complex and a positive result for nontuberculous mycobacteria. The DNA chip test confirmed this organism as a member of the genus Mycobacterium, but could not specify the species. Interestingly, the mycolic acid patterns obtained by HPLC nearly overlapped with those of M. simulans. The sequences of the Mycobacterium 16S rRNA gene and 16S-23S internal transcribed spacer region were unique and were found to have 100% similarity with those of M. riyadhense. After a review of the literature, we report this case as the first Korean case of M. riyadhense lung infection.

Comparison of an Automated Repetitive Sequence-based PCR Microbial Typing System with IS6110-Restriction Fragment Length Polymorphism for Epidemiologic Investigation of Clinical Mycobacterium tuberculosis Isolates in Korea / 대한진단검사의학회지

Tuberculosis remains a severe public health problem worldwide. Presently, genotyping is used for conducting epidemiologic and clinical studies on tuberculosis cases. We evaluated the efficacy of the repetitive sequence-based PCR (rep-PCR)-based DiversiLab(TM) system (bioMerieux, France) over the IS6110-restriction fragment length polymorphism analysis for detecting Mycobacterium tuberculosis. In all, 89 clinical M. tuberculosis isolates collected nationwide from Korea were used. The DiversiLab system allocated the 89 isolates to 8 groups with 1 unique isolate when a similarity level of 95% was applied. Seventy-six isolates of the Beijing family and 13 isolates of non-Beijing family strains were irregularly distributed regardless of rep-PCR groups. The DiversiLab system generated a rapid, sensitive, and standardized result. It can be used to conduct molecular epidemiologic studies to identify clinical M. tuberculosis isolates in Korea.

Annual Report on External Quality Assessment in Blood Bank Tests in Korea (2009) / 임상검사와정도관리

BACKGROUND: We report here the results of surveys for external quality assessment of blood bank tests performed in 2009. METHODS: Survey specimens were sent three times to 488, 491 and 490 participant institutes, and the response rates for the 1st, 2nd and 3rd trial were 97.7%, 98.0%, and 98.0%, respectively. Test items for the surveys were ABO grouping, Rh (D) typing, crossmatching, direct antiglobulin test, antibody screening and antibody identification test. RESULTS: The average accuracy rates of ABO grouping and Rh typing were 99.6-100% and 98.5-100%, respectively. In crossmatching test, the accuracy rates were 99.3-99.8% for the compatible samples, 92.7-100% for the incompatible samples, and 92.6-93.1% for the samples which could be detected as incompatible only by antiglobulin method. The accuracy rates of direct antiglobulin test were 98.5-100% for negative samples and 98.1-98.8% for positive samples. The correctresults were reported by 98.0-100% of the surveyed institutions for antibody screening test and 82.9-100% for antibody identification test. Nineteen institutions gave repeatedly incorrect answers for crossmatching test. Eight institutions out of them gave incorrect answers for all the test specimens sent out 3 times last year. CONCLUSIONS: The overall results of this survey were good, however, it is required that the institutions where the incorrect results were reported should perform corrective actions for quality improvement.

Treatment of Refractory Lateral Epicondylitis with Platelet-Rich Plasma

PURPOSE: To evaluate clinical results of a single percutaneous injection of platelet-rich plasma in patients with refractory lateral epicondylitis. MATERIALS AND METHODS: Between Jan and Dec 2009, fifteen patients (5 male, 10 female) received a diagnosis of lateral epicondylitis of the elbow and were evaluated in this study. Their average age was 43.5 years. All patients were initially given a variety of non-surgical treatments for more than 1year. All patients were considering surgery. These patients were given a single percutaneous injection of 3cc of platelet-rich plasma. To assess pain, we used a visual analogue scale (VAS) at rest and during work & the Patient-Rated Tennis Elbow Evaluation (PRTEE) score. We compared the score before treatment with scores 4 and 12 weeks after treatment. RESULTS: Average VAS scores at rest improved from 4.6 before treatment to 2.5 at week 4, and 1.8 at week 12. The average VAS score while working also improved from 7.8 before treatment to 6.2 at week 4, and 4.25 at week 12. The average PRTEE score improved from 60.13 before treatment to 46.12 at week 4 and 24.6 at week 12. CONCLUSION: Treatment using a single percutaneous injection of platelet-rich plasma in patients with refractory lateral epicondylitis appears to be an effective treatment modality. Platelet-rich plasma should be considered before surgical intervention.

Annual Report on External Quality Assessment in Blood Bank Tests in Korea (2008) / 임상검사와정도관리

We report here the results of surveys for external quality assessment of blood bank tests performed in 2008. Survey specimens were sent three times to 460, 470 and 473 participant institutes, and the response rates for the 1st, 2nd and 3rd trial were 97.6%, 97.7%, and 97.7%, respectively. Test items for the surveys were ABO grouping, Rh (D) typing, crossmatching, direct antiglobulin test, antibody screening and antibody identification test. The average accuracy rates of ABO grouping and Rh typing were 100% and 98.3-100%, respectively. In crossmatching test, the accuracy rates were 97.5-99.7% for the compatible samples, 92.4-99.2% for the incompatible samples, and 88.2-98.9% for the samples which could be detected as incompatible only by antiglobulin method. The accuracy rates of direct antiglobulin test were 98.4-99.7% for negative samples and 93.4-99.7% for positive samples. The correct results were reported by 99.6-100% of the surveyed institutions for antibody screening test and 98.2-100% for antibody identification test. Twenty-three institutions gave repeatedly incorrect answers for crossmatching test. Ten institutions out of them gave incorrect answers for all the test specimens sent out 3 times last year.

Annual Report on External Quality Assessment in Blood Bank Tests in Korea (2007) / 임상검사와정도관리

We report here the results of external quality assessment of blood bank tests performed in 2007. Survey specimens were sent three times to 448, 450, and 455 participant institutes, and the response rates were 99.3%, 97.3%, and 98.0%, respectively. Test items for the surveys were ABO grouping, Rh(D) typing, crossmatching, direct antiglobulin test, antibody screening and identification test. The average accuracy rates of ABO grouping and Rh typing were in the range of 99.5-100% and 98.9-100%, respectively. In crossmatching test, the accuracy rates were 96.0-97.1% for the compatible samples, 89.6-92.4% for the incompatible samples, and 89.6-92.4% for the samples which could be detected as incompatible only by antiglobulin method. The accuracy rates of direct antiglobulin test were 98.0-99.7% for negative samples and 96.3-99.0% for positive samples. The correct results were reported by 95.7-100% of the surveyed institutions for antibody screening test and 98.2-100% for identification test. Fifteen institutions gave repeatedly incorrect answers for crossmatching. Five institutions out of them gave incorrect answers for all the test specimens sent out 3 times last year.

Annual Report on External Quality Assessment in Blood Bank Tests in Korea (2007) / 임상검사와정도관리

We report here the results of external quality assessment of blood bank tests performed in 2007. Survey specimens were sent three times to 448, 450, and 455 participant institutes, and the response rates were 99.3%, 97.3%, and 98.0%, respectively. Test items for the surveys were ABO grouping, Rh(D) typing, crossmatching, direct antiglobulin test, antibody screening and identification test. The average accuracy rates of ABO grouping and Rh typing were in the range of 99.5-100% and 98.9-100%, respectively. In crossmatching test, the accuracy rates were 96.0-97.1% for the compatible samples, 89.6-92.4% for the incompatible samples, and 89.6-92.4% for the samples which could be detected as incompatible only by antiglobulin method. The accuracy rates of direct antiglobulin test were 98.0-99.7% for negative samples and 96.3-99.0% for positive samples. The correct results were reported by 95.7-100% of the surveyed institutions for antibody screening test and 98.2-100% for identification test. Fifteen institutions gave repeatedly incorrect answers for crossmatching. Five institutions out of them gave incorrect answers for all the test specimens sent out 3 times last year.

Clinical significance of E. coli O26 isolates on urine specimen of urinary tract infection / 대한산부인과학회지

OBJECTIVE: Escherichia coli (E. coli) O26 has been the most common type of non-O157 human isolates and it has been related with urinary tract infection and its sequelae. So we investigated the clinical significance of E. coli O26 among the cases of urinary tract infection. METHODS: From January, 2005 to December, 2007, the 22 E. coli isolates that were related with urinary tract infection were analyzed. The isolates were identified biochemically by Vitek 1. We performed antisera test by O157, O26, O111 diagnostic antisera about the 22 E. coli isolates. We reviewed clinical history of the same patients retrospectively. RESULTS: 331 E. coli isolates in the urine specimen were isolated from January, 2005 to December, 2007. 175 E. coli isolates that were related with urinary tract infection were analyzed by O157, O26, O111 antisera test. As a result, 22 isolates (13.5%) were O26 antisera positive. There were 8, 3, and 2 cases of watery diarrhea, hemolytic uremic syndrome, thrombotic thrombocytopenic purpura repectively. CONCLUSION: In our study, because E. coli O26 was pathogenic and developed major complications, we concluded that patients with urinary tract infection with E. coli. should examine the antisera test about E. coli O157 and O26.

Identification of Mycobacteria Species by HPLC and Species Distribution during Five Years at Ulsan University Hospital / 대한진단검사의학회지

BACKGROUND: Infections caused by mycobacteria have been significantly increasing. Due to the difficulty of making a decision about the pathogenicity of mycobacteria, species-level identification is very important for patients' diagnosis and treatment. The purpose of this study was to identify mycobacteria species using a high performance liquid chromatography (HPLC) method and to provide an initial database for the distribution of mycobacteria in Korea. METHODS: Acid fast bacteria isolated from 3,107 clinical specimens were identified by mycolic acid analysis using HPLC. The HPLC patterns were compared with those of standard mycobacteria species. RESULTS: The HPLC patterns were divided into single, double, and triple cluster groups, each group comprising 9, 20, and 4 species, respectively. Mycobacteria and non-tuberculous mycobacteria (NTM) were identifies by HPLC at the rates of 99.5% and 95.6%, respectively. NTM was isolated in 12.4% of the mycobacteria positive specimens. This study also found that there were 20 different NTM species with the distribution of each species ranging from 0.3% to 15.9% of the total NTM. While the rate of NTM has been increasing in Korea, M. avium-intracellulare, M. fortuitum, and M. chelonae are relatively decreasing, and M. kansasii and M. gordonae are relatively increasing. CONCLUSIONS: HPLC method was highly discriminative for the identification of NTM in clinical specimens.

Experience with the Automatic Blood Bank Instrument AutoVue Innova / 대한수혈학회지

BACKGROUND: The AutoVue Innova (Ortho Clinical Diagnostic, Raritan, NJ, USA) is an automatic instrument for blood bank tests, and it has recently been introduced in Korea for the first time at our hospital. This instrument employs column agglutination technology and it performs blood bank tests automatically. We evaluated this instrument and we report on the results. METHODS: We performed ABO/RhD typing and antibody screening for 250 randomly selected samples, and crossmatching for 261 samples with using the AutoVue Innova in parallel with the conventional manual methods. For a sensitivity test, we added 3 samples of A(2)B(3) and 2 samples of weak-D and serially diluted reagent antisera to the test pool and we measured turnaround time (TAT) for the antibody screening test. RESULTS: The concordance rates between AutoVue Innova and the manual methods for ABO/RhD blood typing, antibody screening and crossmatching tests were 99.6%, 100% and 98.9%, respectively. The overall retest rate was 0.5% and the main cause of the discrepancy was revealed to be hemolysis or an inadequate amount of the samples. The overall sensitivity of AutoVue Innova seems to be same as or better than the manual methods. The TAT for the antibody screening test was significantly shorter for the AutoVue Innova (64+/-43 min, n=512) than for the tube method (89+/-57 min, n=99) (P<0.001). CONCLUSION: The test results of AutoVue Innova were accurate and sensitive for the ABO/RhD typing, crossmatching and antibody screening tests. The TAT for the antibody screening test was remarkably shortened up to five times more samples could be tested without an increase of manpower.

Distribution and Clinical Significance of Nontuberculous Mycobacteria Identified by High Performance Liquid Chromatography in Clinical Specimens / 대한임상미생물학회지

BACKGROUND: Infections caused by nontuberculous mycobacteria (NTM) are significantly increasing over the last decade. Due to the uncertainty in the clinical significance of these organisms, their effective diagnosis and treatment has been challenging. The purpose of this study was to investigate the distribution and clinical significance of NTM in clinical specimens. METHODS: Acid-fast culture positive 3,107 clinical specimens were identified by mycolic acid analysis using high performance liquid chromatography (HPLC.) The HPLC patterns of 384 NTM strains were compared with those of standard mycobacterium species. Clinical significance of NTM was investigated by a retrospective study including acid-fast stain and culture, medical history, symptoms and signs, radiological and other laboratory findings, pathologic findings, response to treatment, and follow-up study, and was confirmed according to the guideline of American Thoracic Society. RESULTS: Among the 3,107 Mycobacterium-positive specimens, 384 (12.4%) were found to be positive for NTM. Of these, 367 (95.6%) were successfully identified by HPLC as 19 different species, each of which comprising 0.3% to 15.9% of the total NTM, Studies on the pathogenic role of NTM showed that 0~79.6% of each species or 0~100% of isolates from each specimen could be considered clinically significant. CONCLUSION: HPLC method is highly discriminative for the identification of NTM in clinical specimens. When NTM is isolated from clinical specimens in the Ulsan area, the findings from this study could serve as a database on which to determine its clinical significance depending on species type and also specimen type.