Development of label-free electrochemical impedance spectroscopy for the detection of HLA-B*15:02 and HLA-B*15:21 for the prevention of carbamazepine-induced Stevens-Johnson syndrome.

BACKGROUND: Carbamazepine (CBZ) is an FDA-approved anticonvulsant that is widely used to treat epilepsy, bipolar disorder, trigeminal neuralgia and chronic pain. Several studies have reported a strong association between HLA-B*15:02 and carbamazepine-induced Stevens-Johnson syndrome (SJS) or toxic epidermal necrolysis (TEN). However, the HLA-B75 serotype (HLA-B*15:02, HLA-B*15:08, HLA-B*15:11 and HLA-B*15:21) has been found in patients with carbamazepine-induced SJS/TEN. METHODS: This study aimed to develop label-free electrochemical impedance spectroscopy (EIS) for the detection of HLA-B*15:02 and HLA-B*15:21 after PCR-SSP amplification. A total of 208 DNA samples were tested. The impedance was measured and compared to standard gel electrophoresis. RESULTS: The developed label-free EIS identified HLA-B*15:02 and HLA-B*15:21 alleles with 100% sensitivity (95% CI: 86.773%-100.000%) and 95.05% specificity (95% CI: 90.821%-97.714%), comparable to commercial DMSc 15:02 detection kits. CONCLUSIONS: We successfully developed a novel PCR-SSP associated with signal impedance changes to detect the HLA-B*15:02 allele and HLA-B*15:21 without downstream amplicon size analysis that is suitable for screening individuals before indication of CBZ therapy.

Evaluation of the ESR fast detector and Improve® ESR analyzer as modified Westergren methods for erythrocyte sedimentation rate.

The erythrocyte sedimentation rate (ESR) has been commonly ordered in hematology laboratories and used to screen for monitoring responses to therapy and identifying inflammatory conditions. To overcome the limitations of traditional ESR measurements, various methods have been developed and compared to the established reference method. This study evaluates the analytical performance of ESR fast detector and Improve® ESR analyzer compared to the reference method. Method validation and comparison were performed in 189 volunteer blood samples according to the International Council for Standardization in Hematology recommendations. The analytical efficacy of ESR fast detector and Improve® ESR analyzer was also assessed and compared with the reference method and C-reactive protein (CRP) levels. The results demonstrated that the precision of ESR fast detector and Improve® ESR analyzer was considered as the acceptance criterion for the ESR measurement. The method comparison analysis between the two modified Westergren methods and reference method demonstrated a strong correlation with the Spearman's rank correlation coefficient of 0.94, with a mean difference of -2.1 and -7.7 mm/h in the ESR fast detector and Improve® ESR analyzer, respectively. Analysis of the area under the receiver operating curve illustrated a high analytical performance compared to the reference method and CRP level. The measurement of ESR level using the ESR fast detector and Improve® ESR analyzer is a reliable method and has a high analytical performance, which can be used instead of the reference method for screening inflammatory conditions.

Development of Mia Phenotyping Using Paper-Based Device.

The MNS7 (Mia) blood group antigen is found at a different prevalence among different ethnic groups. Anti-Mia can cause hemolytic disease of the fetus and newborn (HDFN) and both acute- and delayed-type hemolytic transfusion reactions (HTR). Mia typing should be performed in donors to prevent life-threatening hemolytic transfusion reactions. The gel card and standard tube methods still need specialized equipment, centrifugation, and expertise for result interpretation. We used a novel paper-based analytical device (PAD) pre-coated with monoclonal IgM anti-Mia for Mia phenotyping. We measured grey pixel intensity in blood typing results for interpretation processing using OpenCV at the sample (SP) and elution parts (EP); furthermore, we used the SP: EP ratio and F-score as analysis criteria. We typed 214 blood EDTA samples with PAD-Mia and then compared with gel card results for setting an analysis criterion. We observed 100% sensitivity, specificity, and accuracy when we applied the SP: EP ratio and F-score with the optimal criterion (1.07 and 0.17 for SP: EP ratio and F-score, respectively). The validation of PAD-Mia typing for blood donor samples (n = 150) via F-score gave 100% sensitivity and specificity when compared with the gel card method; therefore, we argue that PAD-Mia typing can be used for Mia phenotyping without sero-centrifugation. Moreover, to study the correlation between genotype and phenotype, PCR-SSP was performed to identify GYP(B-A-B) hybrids. The results revealed that all Mia+ blood samples gave a positive with GP. Hut, GP. HF, GP. Mur, GP. Hop, and GP. Bun. Results of the gel card method and PCR-SSP were concordant. Hence, using PAD-Mia typing in blood donors would be helpful for creating a phenotype database of blood donors for reducing alloimmunization risks.