Prediction of Mid-term Platelet Transfusion in Stable Trauma Patients Using Rotational Thromboelastometry

Background@#Rotational thromboelastometry (ROTEM; TEM International GmbH, Munich, Germany) is a global coagulation test that guides evidence-based platelet transfusion in trauma patients. We evaluated ROTEM parameters for predicting mid-term (five days) platelet transfusion in trauma patients. @*Methods@#Maximum clot firmness and clot amplitudes after 5, 10, and 15 mins (A5, A10, and A15, respectively) of fibrin-specific ROTEM (FIBTEM) and extrinsically activated ROTEM (EXTEM) were retrospectively collected from 82 hospitalized, stable, non-bleeding trauma patients after successful initial resuscitation. Platelet-specific ROTEM (PLTEM) was calculated by subtracting FIBTEM from EXTEM. Platelet transfusions were reviewed for five days after ROTEM. @*Results@#The areas under the curve for FIBTEM, EXTEM, and PLTEM predicting platelet concentrate transfusion of > 12 U at mid-term were 0.915–0.923, 0.878–0.896, and 0.551–0.735, respectively. FIBTEM and EXTEM parameters were comparable to those of fibrinogen, fibrin/fibrinogen degradation products, D-dimer, and antithrombin III. Strong correlations (r > 0.7) were noted between platelet count and EXTEM (A5, A10, and A15) or PLTEM (A5), platelet function (per platelet count) and EXTEM (A10 and A15), and fibrinogen levels and all FIBTEM parameters. @*Conclusions@#FIBTEM and EXTEM can reliably predict mid-term platelet transfusion in trauma patients. FIBTEM, EXTEM, and PLTEM parameters correlate with conventional coagulation tests (platelets and fibrinogen).

Comparative Study on the Immunogenicity of COVID-19 mRNA Vaccines in Patients Receiving Adjuvant and Palliative Chemotherapy / 전남의대학술지

This study was conducted to investigate potential differences in vaccine efficacy between patients undergoing palliative chemotherapy and receiving adjuvant chemotherapy. Additionally, the study proved the influence of vaccination timing on vaccine efficacy during active chemotherapy. Anti-receptor-binding domain (RBD) IgG binding antibody assays and surrogate neutralizing antibody assays were performed after BNT162b2 or mRNA-1273 vaccination in 45 solid cancer patients (23 adjuvant and 22 palliative chemotherapy) and in 24 healthy controls before vaccination (baseline), at every two to four weeks after the first (post-dose 1) and the second vaccination (post-dose 2). The levels of anti-RBD IgG and neutralizing antibodies increased significantly from baseline through post-dose 1 to post-dose 2 in all three groups. At the post-dose 1, the anti-RBD IgG and neutralizing antibody levels were significantly lower in cancer patients than in healthy controls. However, by post-dose 2, the seropositivity of anti-RBD IgG and neutralizing antibodies uniformly reached 100% across all groups, with no significant disparity in antibody levels among the three groups. Moreover, the antibody titers were not significantly different between patients with a vaccine and chemotherapy interval of more than 14 days or those with less than 14 days. This study demonstrated that after second doses of mRNA COVID-19 vaccines, humoral immune responses in patients receiving chemotherapy were comparable to those of healthy controls, regardless of whether the purpose of the anti-cancer treatment was palliative or adjuvant. Furthermore, the timing of vaccination did not affect the level of humoral immunity after the second vaccination.

Evaluation of the Appropriateness of Platelet Transfusions at Two Tertiary Hospitals / 대한수혈학회지

Background@#Appropriate platelet transfusion is essential for patient blood management and allocating limited healthcare resources. Therefore, this study evaluated the appropriateness of platelet transfusion in two tertiary hospitals. @*Methods@#At Chonnam National University Hospital (Hospital A) and Chonnam National University Hwasun Hospital (Hospital B), 1,470 platelet transfusions (299 and 1,171 cases at Hospitals A and B, respectively) during a single month were reviewed retrospectively using the Korean Transfusion Guidelines (5th edition). @*Results@#The most common indications were therapeutic transfusion to ensure hemostasis (54.8%) at Hospital A and to prevent spontaneous bleeding in patients with hematologic/oncologic diseases (65.8%) at Hospital B. Overall, 87.3% and 76.3% of transfusions were appropriate at Hospitals A and B, respectively. According to the different transfusion indications, the therapeutic transfusions were appropriate in more than 80% of cases in both hospitals.The appropriateness of prophylactic transfusions against spontaneous bleeding was 80.7% and 69.3%, respectively, and those before surgery or invasive procedures were 72.0% and 66.2%, respectively. Of the 38 and 278 inappropriate transfusions in Hospitals A and B, respectively (as determined by pre-transfusion platelet counts), most cases had platelet counts between 50 and 100×109 /L in Hospital A (23 cases) and between 20 and 50×109 /L in Hospital B (198 cases). @*Conclusion@#The two hospitals differed in terms of transfusion indications, appropriateness, and cases of inappropriateness. The indications and appropriateness of platelet transfusion should be reviewed in real practice on a hospital-by-hospital basis to improve transfusion management.

Preliminary Investigation on Efficacy and Safety of Substance P-Coated Stent for Promoting Re-Endothelialization: A Porcine Coronary Artery Restenosis Model

BACKGROUND@#Current polymer-based drug-eluting stents (DESs) have fundamental issues about inflammation and delayed re-endothelializaton of the vessel wall. Substance-P (SP), which plays an important role in inflammation and endothelial cells, has not yet been applied to coronary stents. Therefore, this study compares poly lactic-co-glycolic acid (PLGA)-based everolimus-eluting stents (PLGA-EESs) versus 2-methacryloyloxyethyl phosphorylcholine (MPC)-based SP-eluting stents (MPC-SPs) in in-vitro and in-vivo models. @*METHODS@#The morphology of the stent surface and peptide/drug release kinetics from stents were evaluated. The invitro proliferative effect of SP released from MPC-SP is evaluated using human umbilical vein endothelial cell. Finally, the safety and efficacy of the stent are evaluated after inserting it into a pig’s coronary artery. @*RESULTS@#Similar to PLGA-EES, MPC-SP had a uniform surface morphology with very thin coating layer thickness (2.074 lm). MPC-SP showed sustained drug release of SP for over 2 weeks. Endothelial cell proliferation was significantly increased in groups treated with SP (n = 3) compared with the control (n = 3) and those with everolimus (n = 3) (SP:118.9 ± 7.61% vs. everolimus: 64.3 ± 12.37% vs. the control: 100 ± 6.64%, p < 0.05). In the animal study, the percent stenosis was higher in MPC-SP group (n = 7) compared to PLGA-EES group (n = 7) (MPC-SP: 28.6 ± 10.7% vs. PLGAEES: 16.7 ± 6.3%, p < 0.05). MPC-SP group showed, however, lower inflammation (MPC-SP: 0.3 ± 0.26 vs. PLGAEES: 1.2 ± 0.48, p < 0.05) and fibrin deposition (MPC-SP: 1.0 ± 0.73 vs. PLGA-EES: 1.5 ± 0.59, p < 0.05) around the stent strut. MPC-SP showed more increased expression of cluster of differentiation 31, suggesting enhanced reendothelialization. @*CONCLUSION@#Compared to PLGA-EES, MPC-SP demonstrated more decreased inflammation of the vascular wall and enhanced re-endothelialization and stent coverage. Hence, MPC-SP has the potential therapeutic benefits for the treatment of coronary artery disease by solving limitations of currently available DESs.

Altered Frequency, Activation, and Clinical Relevance of Circulating Innate and Innate-Like Lymphocytes in Patients With Alcoholic Liver Cirrhosis

Alcoholic liver cirrhosis (ALC) is caused by chronic alcohol overconsumption and might be linked to dysregulated immune responses in the gut-liver axis. However, there is a lack of comprehensive research on levels and functions of innate lymphocytes including mucosalassociated invariant T (MAIT) cells, NKT cells, and NK (NK) cells in ALC patients. Thus, the aim of this study was to examine the levels and function of these cells, evaluate their clinical relevance, and explore their immunologic roles in the pathogenesis of ALC. Peripheral blood samples from ALC patients (n = 31) and healthy controls (HCs, n = 31) were collected. MAIT cells, NKT cells, NK cells, cytokines, CD69, PD-1, and lymphocyte-activation gene 3 (LAG-3) levels were measured by flow cytometry. Percentages and numbers of circulating MAIT cells, NKT cells, and NK cells were significantly reduced in ALC patients than in HCs. MAIT cell exhibited increased production of IL-17 and expression levels of CD69, PD-1, and LAG-3. NKT cells displayed decreased production of IFN-γ and IL-4. NK cells showed elevated CD69 expression. Absolute MAIT cell levels were positively correlated with lymphocyte count but negatively correlated with C-reactive protein. In addition, NKT cell levels were negatively correlated with hemoglobin levels. Furthermore, log-transformed absolute MAIT cell levels were negatively correlated with the Age, Bilirubin, INR, and Creatinine score. This study demonstrates that circulating MAIT cells, NKT cells, and NK cells are numerically deficient in ALC patients, and the degree of cytokine production and activation status also changed. Besides, some of their deficiencies are related to several clinical parameters. These findings provide important information about immune responses of ALC patients.

Performance Evaluation of VITEK MS for the Identification of a Wide Spectrum of Clinically Relevant Filamentous Fungi Using a Korean Collection

The correct identification of filamentous fungi is challenging. We evaluated the performance of the VITEK MS v3.0 system (bioMérieux, Marcy-l’Étoile, France) for the identification of a wide spectrum of clinically relevant filamentous fungi using a Korean collection. Strains that were added to the upgraded v3.2 database were additionally identified by the VITEK MS v3.2 system. Of the 105 tested isolates, including 37 Aspergillus (nine species), 41 dermatophytes (seven species), and 27 other molds (17 species), 43 (41.0%) showed “no identification” or “multiple species identification” results at the initial VITEK MS testing; these isolates were retested using the same method. Compared with sequence-based identification, the correct identification rate using VITEK MS for Aspergillus, dermatophytes, other molds, and total mold isolates was 67.6%, 56.1%, 48.1%, and 58.1% at the initial testing and 94.6%, 78.0%, 55.6%, and 78.1% with retesting, respectively. Following retesting, 19 (18.1%) and two (1.9%) isolates showed “no identification” and “misidentification” results, respectively. VITEK MS reliably identified various filamentous fungi recovered in Korea, with a very low rate of misidentification

Viral Load Kinetics of SARS-CoV-2Infection in Saliva in Korean Patients:a Prospective Multi-center Comparative Study

Background@#This study was performed to compare the viral load and kinetics of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) in saliva with those in standard nasopharyngeal/oropharyngeal (NP/OP) swabs. @*Methods@#Fifteen patients with SARS-CoV-2 infection from four hospitals were prospectively enrolled and matched samples of nasopharyngeal/oropharyngeal swabs and saliva were collected at Day 1 of admission and every other day till consequently negative for two times. Real-time reverse transcription polymerase chain reaction (rRT-PCR) was performed to detect the envelope (E) and RNA-dependent RNA polymerase (RdRP) genes. @*Results@#The cycle threshold values of saliva were comparable to those of NP/OP swabs overall (P = 0.720, Mann–Whitney U test). However, the overall sensitivity of rRT-PCR using saliva was 64% (34/53), which is lower than the 77% (41/53) using NP/OP swabs. The sensitivity of rRT-PCR using saliva was especially lower in early stage of symptom onset (1–5 days; 8/15; 53%) and in patients who did not have sputum (12/22; 55%). @*Conclusion@#Saliva sample itself is not appropriate for initial diagnosis of coronavirus disease 2019 (COVID-19) to replace NP/OP swabs, especially for the person who does not produce sputum. COVID-19 cannot be excluded when the test using saliva is negative, and it is necessary to retest using NP/OP swabs.

Air and Environmental Contamination Caused by COVID-19 Patients: a MultiCenter Study

Background@#The purpose of this study was to determine the extent of air and surface contamination of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) in four health care facilities with hospitalized coronavirus disease 2019 (COVID-19) patients. @*Methods@#We investigated air and environmental contamination in the rooms of eight COVID-19 patients in four hospitals. Some patients were in negative-pressure rooms, and others were not. None had undergone aerosol-generating procedures. On days 0, 3, 5, and 7 of hospitalization, the surfaces in the rooms and anterooms were swabbed, and air samples were collected 2 m from the patient and from the anterooms. @*Results@#All 52 air samples were negative for SARS-CoV-2 RNA. Widespread surface contamination of SARS-CoV-2 RNA was observed. In total, 89 of 320 (27%) environmental surface samples were positive for SARS-CoV-2 RNA. Surface contamination of SARSCoV-2 RNA was common in rooms without surface disinfection and in rooms sprayed with disinfectant twice a day. However, SARS-CoV-2 RNA was not detected in a room cleaned with disinfectant wipes on a regular basis. @*Conclusion@#Our data suggest that remote (> 2 m) airborne transmission of SARS-CoV-2 from hospitalized COVID-19 patients is uncommon when aerosol-generating procedures have not been performed. Surface contamination was widespread, except in a room routinely cleaned with disinfectant wipes.

Internal Quality Assurance Status of Stool Examination as Assessed by a Questionnaire in Korean Clinical Laboratories

This study aimed to survey the status of quality control (QC) assurance for stool examinations at clinical laboratories in Korea. We sent a questionnaire related to QC practices in stool examination by electronic mail to Korean clinical laboratories that performed stool examination. Overall, 20 of the 39 laboratories (51.3%) reported performing stool concentration methods, and 28 (71.8%) examined the slides using only saline. A large proportion (74.4%) of respondents did not check the internal QC because of the restriction of appropriate control materials. Only four laboratories (10.3%) checked the reactivity of the dye solution routinely. For appropriate external QC systems, QC slides (43.6%) were preferred, followed by QC materials (30.8%), virtual slides (17.9%), and a combination of the above options (7.7%). The most commonly observed parasites in stool samples at the clinical laboratories were Clonorchis sinensis (75%), followed by Endolimax nana, Enterobius vermicularis, and Entamoeba coli. The present study describes the difficulties in internal QC assessment due to the absence of standardized QC materials and systems. We hope the findings of this report will provide a foundation for a QC assessment program for stool examinations in the near future.

Report on the External Quality Assessment Scheme of Serologic Tests for Syphilis in Korea (2016–2017)

The 2016–2017 surveys on the external quality assessment scheme for serologic tests for syphilis in Korea were conducted by the Korean Association of External Quality Assessment Service. Proficiency testing (PT) panels consisting of three pooled serum samples were shipped to 430 and 432 laboratories participating in the program in the 1st and 2nd trials of 2016 and 465 and 503 laboratories in the 1st and 2nd trials of 2017, respectively. The rates of returning results were 94.2% and 50.2% for non-treponemal and treponemal tests, respectively, in the 1st trial of 2016; 94.7% and 49.5% in the 2nd trial of 2016; 94.2% and 49.5% in the 1st trial of 2017; and 92.8% and 48.7% in the 2nd trial of 2017, respectively. The most commonly used methods for non-treponemal tests were rapid plasma reagin (RPR) card test, followed by RPR turbidoimmunoassay and venereal disease research laboratory tests. The most commonly used methods for treponemal tests were Treponema pallidum particle agglutination, followed by immunochromatographic assay, Treponema pallidum latex agglutination, chemiluminescence immunoassay, and fluorescent treponemal antibody-absorption. The accuracy rates of the 2017 PT for non-treponemal and treponemal tests were 92.5%–99.8% and 93.3%–100.0%, respectively, which were significantly lower compared to the 98.4%–100.0% and 97.0%–100.0% in 2016. A possible explanation for the lower accuracy rates in the 2017 PT survey is the matrix effect caused by pooling multiple individual serum samples. These data suggest that pooling of serum samples obtained from a small number of donors may help avoid the matrix effect affecting standard materials used for syphilis serology PT.

Deficiencies of Circulating Mucosal-associated Invariant T Cells and Natural Killer T Cells in Patients with Multiple Trauma

Mucosal-associated invariant T (MAIT) cells and natural killer T (NKT) cells are known to play important roles in autoimmunity, infectious diseases and cancers. However, little is known about the roles of these invariant T cells in multiple trauma. The purposes of this study were to examine MAIT and NKT cell levels in patients with multiple trauma and to investigate potential relationships between these cell levels and clinical parameters. The study cohort was composed of 14 patients with multiple trauma and 22 non-injured healthy controls (HCs). Circulating MAIT and NKT cell levels in the peripheral blood were measured by flow cytometry. The severity of injury was categorised according to the scoring systems, such as Acute Physiology and Chronic Health Evaluation (APACHE) II score, Simplified Acute Physiology Score (SAPS) II, and Injury Severity Score (ISS). Circulating MAIT and NKT cell numbers were significantly lower in multiple trauma patients than in HCs. Linear regression analysis showed that circulating MAIT cell numbers were significantly correlated with age, APACHE II, SAPS II, ISS category, hemoglobin, and platelet count. NKT cell numbers in the peripheral blood were found to be significantly correlated with APACHE II, SAPS II, and ISS category. This study shows numerical deficiencies of circulating MAIT cells and NKT cells in multiple trauma. In addition, these invariant T cell deficiencies were found to be associated with disease severity. These findings provide important information for predicting the prognosis of multiple trauma.

Comparison of the Bruker Biotyper and VITEK MS Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry Systems Using a Formic Acid Extraction Method to Identify Common and Uncommon Yeast Isolates

BACKGROUND: Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) allows rapid and accurate identification of clinical yeast isolates. In-tube formic acid/acetonitrile (FA/ACN) extraction is recommended prior to the analysis with MALDI Biotyper, but the direct on-plate FA extraction is simpler. We compared the Biotyper with the VITEK MS for the identification of various clinically relevant yeast species, focusing on the use of the FA extraction method. METHODS: We analyzed 309 clinical isolates of 42 yeast species (four common Candida species, Cryptococcus neoformans, and 37 uncommon yeast species) using the Biotyper and VITEK MS systems. FA extraction was used initially for all isolates. If ‘no identification' result was obtained following the initial FA extraction, these samples were then retested by using FA (both systems, additive FA) or FA/ACN (Biotyper only, additive FA/ACN) extraction. These results were compared with those obtained by sequence-based identification. RESULTS: Both systems correctly identified all 158 isolates of the four common Candida species after the initial FA extraction. The Biotyper correctly identified 8.7%, 30.4%, and 100% of 23 C. neoformans isolates after performing initial FA, additive FA, and FA/ACN extractions, respectively, while VITEK MS identified all C. neoformans isolates after the initial FA extraction. Both systems had comparable identification rates of 37 uncommon yeast species (128 isolates), following the initial FA (Biotyper, 74.2%; VITEK MS, 73.4%) or additive FA (Biotyper, 82.0%; VITEK MS, 73.4%). CONCLUSIONS: The identification rate of most common and uncommon yeast isolates is comparable between simple FA extraction/Biotyper method and VITEK MS methods, but FA/ACN extraction is necessary for C. neoformans identification by Biotyper.

Increasing Burden of Nontuberculous Mycobacteria in Korea

No abstract available.

Detection of Intestinal Parasites in Diarrhea Samples Using Various Diagnostic Methods and Evaluation of the Stability of In-house Quality Control Materials for Stool Examination

BACKGROUND: Because of a lack of quality control (QC) materials, stool examination has not been standardised. This study examined intestinal parasites in diarrhea specimens to manufacture and evaluate the performance stability of QC materials for stool examination. METHODS: This study examined diarrhea specimens submitted for stool culture. Microscopic examination was performed using the direct smear and formalin-ether concentration method (Military General Laboratory, MGL). Enzyme-linked immunosorbent assay (ELISA) kits (R-Biopharm AG, Germany) and xTAG Gastrointestinal Pathogen Panel (Luminex Corp., USA) were used for the three major protozoa: Cryptosporidium parvum, Giardia lamblia, and Entamoeba histolytica. Polymerase chain reaction (PCR) was performed for Dientamoeba fragilis and Blastocystis hominis. The QC materials for stool examination were generated using Diphyllobothrium nihonkaiense ova. The manufactured QC materials were evaluated under different storage conditions, with varying preservatives, temperatures, and storage times. RESULTS: From November 2015 to April 2016, 82 diarrhea specimens were collected and tested. All results from microscopy and ELISA were negative; C. parvum (n=2) and G. lamblia (n=1) were detected by xTAG, while D. fragilis (n=10) and B. hominis (n=2) were detected by PCR. High- and low-concentration QC materials were manufactured. Using the high-concentration QC material, ova were observed in all storage conditions using MGL. Using the low-concentration QC material, the ova were observed until 14 days, but not after 3 weeks. CONCLUSIONS: It should be considered for making QC materials for stool examinations that focus on D. fragilis and B. hominis frequently found in Korea and with the caution to the low-concentration of QC materials could be unstable.

Performance Evaluation of Automated Clinical Chemistry Analyzer for Indocyanine Green (ICG) R15 Test

BACKGROUND: The conventional indocyanine green retention rate at 15 minutes (ICG R15) test is inefficient and inconvenient because it requires the use of a manual spectrophotometer and several samples per patient. This study aimed to establish the automation of the ICG R15 test using an automated clinical chemistry analyzer, and to evaluate the calculation of R15 with a small number of samples. METHODS: The performance of the AU5832 (Beckman Coulter, USA) for determining ICG concentration was evaluated in accordance with the Clinical Laboratory Standards Institute (CLSI) guidelines. The R15 results for 77 patients determined by spectrophotometry and AU5832 were compared. We evaluated the calculation of R15 with three samples, except for one sample in which the results had been obtained previously, at 5, 10, and 15 minutes after injection of ICG into the patients, and compared the results with those obtained with four samples. RESULTS: The automated ICG test using the AU5832 system showed proper performances according to CLSI. Although the difference in the R15 results between the two methods was within the 95% confidence interval, the R15 was adjusted by the regression equation because it was slightly lower according to the automated method compared with the manual method. The R15 with three samples (0, 5, and 15 minutes) showed the best correlation with conventional R15 with four samples (r2=0.996). Compared with the manual method, the R15 result using the AU5832 showed excellent agreement with four samples (kappa value 0.904) and with three samples (kappa value 0.880). CONCLUSIONS: The ICG R15 test using the AU5832 system is comparable with the conventional method in clinical use.

Clinical and Hematological Effects of Tocilizumab on Serum Hepcidin, Anemia Response and Disease Activity in Patients with Active Rheumatoid Arthritis

OBJECTIVE: The purpose of this study is to evaluate the clinical and hematological effects of tocilizumab in active rheumatoid arthritis (RA) patients. METHODS: Fourteen patients with active RA were enrolled in this study. The patients received tocilizumab 8 mg/kg intravenously every four weeks for 6 months. Disease activity, anemia-related factors including serum hepcidin-25, and hematological parameters were monitored at baseline and at 1, 3, and 6 months after the initiation of treatment. RESULTS: Significant reductions in tender joint count, swollen joint count, visual analogue scale, erythrocyte sedimentation rate (ESR), and C-reactive (CRP) protein plus reductions in a 28-joint disease activity score were observed within one month after the first tocilizumab treatment. These effects lasted throughout the six-month study period. In addition, significant improvements in anemia-related factors such as hepcidin-25, ferritin, iron, hemoglobin, red blood cell counts and mean corpuscular volume were observed during the treatment period. Hematological parameters were improved with reductions in counts for leukocytes, monocytes, neutrophils, and platelets. The lymphocyte counts and their subset numbers were unchanged. Changes in hepcidin levels showed significant correlation with changes in CRP, ESR, ferritin, hemoglobin and counts for red blood cells, leukocytes, and neutrophils during the treatment period. CONCLUSION: This study demonstrates that tocilizumab significantly and meaningfully reduces disease burden in patients with active RA. In addition, tocilizumab diminishes the levels of inflammatory anemia by inhibiting hepcidin production. These clinical data provide evidence of a favorable outcome from tocilizumab in RA.

Constitutional Chromosomal Abnormality Identified in a Sibling Donor After Bone Marrow Stem Cell Transplantation in a Pediatric Patient with Acute Megakaryoblastic Leukemia

No abstract available.

Comparison of AdvanSure TB/NTM PCR and COBAS TaqMan MTB PCR for Detection of Mycobacterium tuberculosis Complex in Routine Clinical Practice

The AdvanSure tuberculosis/non-tuberculous mycobacterium (TB/NTM) PCR (LG Life Science, Korea) and COBAS TaqMan Mycobacterium tuberculosis (MTB) PCR (Roche Diagnostics, USA) are commonly used in clinical microbiology laboratories. We aimed to evaluate these two commercial real-time PCR assays for detection of MTB in a large set of clinical samples over a two-year period. AdvanSure TB/NTM PCR and COBAS TaqMan MTB PCR were performed on 9,119 (75.2%) and 3,010 (24.8%) of 12,129 (9,728 respiratory and 2,401 non-respiratory) MTB specimens, with 361 (4.0%) and 102 (3.4%) acid-fast bacilli (AFB)-positive results, respectively. In MTB culture, 788 (6.5%) MTB and 514 (4.2%) NTM were identified. The total sensitivity and specificity of the AdvanSure assay were 67.8% (95% confidence interval [CI], 63.9-71.6) and 98.3% (95% CI, 98.0-98.6), while those of the COBAS TaqMan assay were 67.2% (95% CI, 60.0-73.8) and 98.4% (95% CI, 97.9-98.9), respectively. The sensitivities and specificities of the AdvanSure and COBAS TaqMan assays for AFB-positive and AFB-negative samples were comparable. Furthermore, the AdvanSure assay showed fewer invalid results compared with the COBAS TaqMan assay (5.0 vs. 20.4 invalid results/1,000 tests, P<0.001). AdvanSure assay represents a comparable yet more reliable method than COBAS TaqMan for the identification of mycobacteria in routine clinical microbiology.

Mucosal-associated Invariant T cells: A New Player in Innate Immunity

Mucosal-associated invariant T (MAIT) cells are evolutionarily conserved T cells that are restricted by the non-classical major histocompatibility complex class-1b molecule MR1. MAIT cells recognize riboflavin (vitamin B2) derivatives in a MR1-dependent manner. Following antigen recongnition, MAIT cells rapidly produce Th1/Th17 cytokines, such as interferon-gamma and interleukin-17, in an innate-like manner. MAIT cells maintain an activated phenotype throughout the course of an infection, secrete inflammatory cytokines, and have the potential to directly kill infected cells, thus, playing an important role in controlling the host response. In this review, we discuss current knowledge regarding the role of MAIT cells in infectious diseases, cancers, and autoimmune diseases.

Deficiencies of Circulating Mucosal-associated Invariant T Cells and Natural Killer T Cells in Patients with Acute Cholecystitis

Mucosal-associated invariant T (MAIT) cells and natural killer T (NKT) cells are known to play crucial roles in a variety of diseases, including autoimmunity, infectious diseases, and cancers. However, little is known about the roles of these invariant T cells in acute cholecystitis. The purposes of this study were to examine the levels of MAIT cells and NKT cells in patients with acute cholecystitis and to investigate potential relationships between clinical parameters and these cell levels. Thirty patients with pathologically proven acute cholecystitis and 47 age- and sex-matched healthy controls were enrolled. Disease grades were classified according to the revised Tokyo guidelines (TG13) for the severity assessment for acute cholecystitis. Levels of MAIT and NKT cells in peripheral blood were measured by flow cytometry. Circulating MAIT and NKT cell numbers were significantly lower in acute cholecystitis patients than in healthy controls, and these deficiencies in MAIT cells and NKT cell numbers were associated with aging in acute cholecystitis patients. Notably, a reduction in NKT cell numbers was found to be associated with severe TG13 grade, death, and high blood urea nitrogen levels. The study shows numerical deficiencies of circulating MAIT and NKT cells and age-related decline of these invariant T cells. In addition, NKT cell deficiency was associated with acute cholecystitis severity and outcome. These findings provide an information regarding the monitoring of these changes in circulating MAIT and NKT cell numbers during the course of acute cholecystitis and predicting prognosis.