Evaluation of Multiplex Rapid Antigen Test for the Detection of SARS-CoV-2 and Influenza A/B in Respiratory Samples.

BACKGROUND: There is little data about the performance of multiplex rapid antigen tests (RATs) on the detection of SARS-CoV-2, influenza A (Flu A), and influenza B (Flu B). This study is to evaluate the performance of Panbio COVID-19/Flu A&B rapid panel (Abbott Diagnostics, Korea) and analyze the factors influencing its sensitivity. METHODS: Nasopharyngeal swabs were collected and stored at the Korea University Anam hospital. In total, 400 residual samples from nasopharyngeal swabs were examined. The diagnostic accuracy of RAT was compared to that of RT-qPCR using the Allplex SARS-CoV-2/FluA/FluB/RSV Assay (Seegene, Seoul, South Korea). RESULTS: Panbio COVID-19/Flu A&B rapid panel showed the sensitivities of 88.0%, 92.0%, and 100% for SARS-CoV-2, Flu A, and Flu B, respectively, and specificities of 100% for all. The agreements with previously licensed single-plex RATs were shown to be high. In the analysis of variables affecting sensitivity, inappropriate sampling time after symptom onset (STASO) and high cycle threshold (Ct value) were shown to negatively affect the sensi-tivity. CONCLUSIONS: In conclusion, the multiplex RAT is useful for diagnosing SARS-CoV-2 and Flu A/B, but more clinical studies are needed.

Performance Evaluation of Three Antibody Binding Assays, a Neutralizing Antibody Assay, and an Interferon-Gamma Release Assay for SARS-CoV-2 According to Vaccine Type in Vaccinated Group.

We evaluated the performance of SARS-CoV-2 assays in the vaccinated group using receptor-binding domain antibody assays (RBD Ab assay), neutralizing antibody assay (nAb assay), and interferon-gamma release assay (IGR assay). We also compared the performance of the SARS-CoV-2 assays based on vaccine type in a large population. We collected 1851 samples from vaccinated individuals with vector, mix-and-match (MM), and mRNA vaccines. The performance of the RBD Ab assays was assessed by SARS-CoV-2 IgG II Quant (Abbott Laboratories, Sligo, Ireland), SARS-CoV-2 IgG (Beckman Coulter, CA, USA), and anti-SARS-CoV-2 S (Roche Diagnostics GmbH, Mannheim, Germany). The nAb assay was assessed by cPass SARS-CoV-2 neutralization antibody detection kits (GenScript, NJ, USA). The IGR assay was assessed by QuantiFERON (Qiagen, Venlo, The Netherlands). Median values of the RBD Ab assays and nAb assay sequentially increased after the first and second vaccinations. RBD Ab assays and nAb assay showed very strong correlations. The median values of the RBD Ab, nAb, and IGR were higher in the mRNA vaccine group than in the vector and MM vaccine groups. The agreement and correlation among the RBD Ab assays, nAb assay, and IGR assay were higher in the mRNA vaccine group than in the vector and MM vaccine groups. We compared the performance of the RBD Ab assay, nAb assay, and IGR assay based on the vaccine types using the RBD Ab, nAb, and IGR assays. This study provides a better understanding of the assessment of humoral and cellular immune responses after vaccination.

HPLC-MS/MS Method Validation for Antifungal Agents in Human Serum in Clinical Application.

BACKGROUND: Therapeutic drug monitoring (TDM) of antifungal drugs is recommended. LC-MS/MS outperforms bioassay and high-performance liquid chromatography (HPLC) for TDM. In this study, we validated TDM for voriconazole, posaconazole, and itraconazole using HPLC-MS/MS with the multiple reaction monitoring (MRM) method. METHODS: For the validation of LC-MS/MS for antifungal TDM, accuracy, precision, linearity, carryover, lower limit of quantitation (LLOQ), ion suppression, and sample stability tests were performed according to the guidelines of the United States Food and Drug Administration (FDA) and the Clinical and Laboratory Standards Institute (CLSI). RESULTS: The LC-MS/MS triazole method showed that all analytes had biases less than 8.9% and coefficients of variation (CV) less than 7.7%. The linearity was validated over the ranges of 0.20 to 5.86 mg/L for voriconazole, 0.12 to 4.96 mg/L for posaconazole, 0.09 to 1.85 mg/L for itraconazole, and 0.12 to 2.38 mg/L for OH-itraconazole. Ion suppression and carryover were negligible. The lower limits of quantitation (LLOQs) for voriconazole, posaconazole, itraconazole, and OH-itraconazole were 0.114 mg/L, 0.206 mg/L, 0.118 mg/L, and 0.065 mg/L, respectively. Voriconazole, posaconazole, itraconazole, and OH-itraconazole can be stored at 4℃ for 4 - 7 days, according to sample stability. Sample preparation took < 15 minutes per batch, and analytical run time was 5 minutes per sample. CONCLUSIONS: We developed and validated a simple, reliable, and quick LC-MS/MS method for triazole antifungal agents TDM suitable for routine hospital practice.

Development and Validation of a U-HPLC-MS/MS Method for the Concurrent Measurement of four Immunosuppressants in Whole Blood.

BACKGROUND: This study aimed to develop and validate a U-HPLC-MS/MS method for simultaneous determination of four immunosuppressants in human whole blood. METHODS: The method was based on the injection of 20 µL of calibrators and controls pretreated with the liquid phase extraction method for chromatography separation and mass spectrometry determination. LPE offline was performed by adding 0.1 mol/L ZnSO4 and acetonitrile, while separation of target compounds was achieved within 2.5 minutes by a Zorbax Eclipse XDB-C8 column using ammonium acetate and ACN mixed with formic acid as solvents. RESULTS: The assay offers ng/mL detection limits (from 1.1 to 12.4 ng/mL), accuracy (% deviation from -4.4% to 5.6%), precision (CV less than 15% at all QC levels), and linearity (from 23.4 to 948 ng/mL for CsA, from 2.11 to 45.5 ng/mL for TAC, SIR and EVR). The recovery and matrix results were acceptable, and the carryover was less than 1%. The results of method comparison show that IA-based methods overestimated the concentration of drugs compared with the MS-based method. Comparing our MS-based method with external LC-MS/MS showed that the results were within 2 SDs. CONCLUSIONS: We have developed a reliable assay for the analysis of CsA, TAC, SIR and EVR in whole blood using U-HPLC-MS/MS.

Humoral and Cellular Immune Responses to Vector, Mix-and-Match, or mRNA Vaccines against SARS-CoV-2 and the Relationship between the Two Immune Responses.

We investigated how differences in age, sex, or vaccine type can affect humoral and cellular immune responses after vaccination with vector (ChAdOx1 nCoV-19), mix-and-match (first, ChAdOx1 nCoV-19, and second, BNT162b2), or mRNA (BNT162b2 or mRNA-1273) vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Venous blood was collected from 573 subjects (vector, 396; mix-and-match, 96; and mRNA, 81) before the first vaccination (T0), 7 to 8 weeks (vector) or 3 to 4 weeks (mRNA) after the first vaccination (T1), and 3 to 4 weeks after the second vaccination (T2). The humoral and cellular immune responses were evaluated using Elecsys anti-SARS-CoV-2 (Roche), Alinity SARS-CoV-2 IgG II Quant (Abbott), cPass SARS-CoV-2 neutralization antibody detection (GenScript), and QuantiFERON SARS-CoV-2 (Qiagen) kits. At T1, the levels of the receptor-binding domain antibodies (RBD Ab) and neutralizing antibodies (NAb) decreased with aging, but interferon gamma release (IGR) levels increased. The RBD Ab, NAb, and IGR levels were higher in females than in males at T1 and T2. The NAb levels were higher in the mix-and-match and mRNA vaccine groups than in the vector vaccine group at T2. The RBD Ab and IGR levels were higher in the mRNA vaccine group than in the vector or mix-and-match vaccine groups at T2. The optimal cutoffs for RBD Ab and NAb, which were used to determine the presence of T cell responses, were 5.7 binding antibody units per milliliter (BAU mL-1) and 12.0 IU mL-1, respectively. Age, sex, and vaccine type affected the humoral and cellular immune responses, and T cell responses could be estimated from RBD Ab and NAb levels. IMPORTANCE There have been few studies that comprehensively evaluated factors affecting immune responses and the correlation between humoral and cellular immune responses after vector, mix-and-match, and mRNA vaccines against SARS-CoV-2. Therefore, we analyzed the effects of age, sex, and the different vaccine regimens on the immune responses to vaccination against SARS-CoV-2. The correlation between humoral and cellular immune responses and the cutoffs were derived for RBD antibodies and neutralizing antibodies to predict the presence of the cellular immune responses. In this comprehensive study, we demonstrated that there were differences in the immune responses induced after vaccination depending on the age and sex of an individual. Among the three vaccine regimens, the mix-and-match and mRNA vaccines induced the most robust immune responses. Finally, the proposed optimal cutoffs for RBD and neutralizing antibodies may be useful for predicting cellular immune responses when assays for cellular immune responses are not available.

Which Approach Is Most Optimal for Needle Electromyographic Examination of the Biceps Femoris Short Head: Medial or Lateral?

OBJECTIVE: To investigate the anatomical characteristics of the biceps femoris short head (BS) and determine the optimal needle placement for BS examination. METHODS: Twenty-one lower limbs were dissected. The distances from the medial and lateral margins of the biceps femoris long head (BL) tendon to the common fibular nerve (CFN) (M_CFN_VD and L_CFN_VD, respectively) and the distance from the lateral margin of the BL tendon to the lateral margin of the BS (L_BS_HD) were measured 5 cm proximal to the tip of the fibular head (P1), four fingerbreadths proximal to the tip of the fibular head (P2), and at the upper apex of the popliteal fossa (P3). RESULTS: The BS was located lateral to the BL tendon. The CFN was located along the medial margin of the BL tendon. The median values were 2.0 (P1), 3.0 (P2), and 0 mm (P3) for M_CFN_VD; and 17.4 (P1), 20.2 (P2), and 21.8 mm (P3) for L_CFN_VD; and 8.1 (P1), 8.8 (P2), and 13.0 mm (P3) for L_BS_VD. CONCLUSION: The lateral approach to the BL tendon was safer than the medial approach for examining the BS. Amore proximal insertion site around the upper apex of the popliteal fossa was more accurate than the distal insertion site. In this study, we propose a safer and more accurate approach for electromyography of the BS.

Sonography-guided trigger point injections in abdominal myofascial pain syndrome.

Even though chronic abdominal pain is 1 of the most common reasons for hospital visits, diagnostic testing is often time-consuming and treatment is inadequate. Abdominal myofascial pain syndrome (AMPS) is usually not included as a differential diagnosis, but it should be considered in cases of chronic abdominal pain. The purpose of this study was to investigate the clinical characteristics of AMPS and to assess the effect of sonography-guided trigger point injections (TPI).A total of 100 patients with AMPS from 2012 to 2018 were retrospectively evaluated for clinical characteristics and TPI effects. AMPS was diagnosed using Srinivasan and Greenbaum's criteria, and the TPIs were performed at intervals of 2 to 4 weeks. The Visual Analog Scale (VAS) ratio was calculated by subtracting the final VAS from the initial VAS score and dividing it by the initial VAS score after injections, and the patients were divided into 4 groups: non-responders, mild, moderate, and good responders.The median duration of pain was 12 months, and the median number of hospital visits before TPI was 2. Of the 100 patients, 66 (66%) were categorized as good responders, 11 (11%) as moderate responders, 7 (6.9%) as mild responders, and 16 (15.7%) as non-responders. When the initial and final VAS scores were compared, the sonography-guided injections were found to be effective in alleviating pain (P < .001). Moreover, patients who received the injections 2 or more times tended to have more significant pain reduction than those who received a single injection (P < .001).Patients with AMPS suffer from long-term pain and undergo many hospital visits and diagnostic tests. TPI with lidocaine can be an effective and safe treatment for patients with chronic AMPS.