Performance characteristics of the MultiCode-RTx hepatitis C virus load test targeting the 3' untranslated region.

Viral load testing for hepatitis C virus (HCV) RNA has become a key parameter in the diagnosis of infection and treatment monitoring. This study evaluated the performance characteristics of the MultiCode-RTx HCV assay (MultiCode; EraGen Biosciences, Inc., Madison, WI), a real-time PCR test targeting the 3' untranslated region (UTR) of the HCV genome, compared to the TaqMan HCV load ASR assay (TaqMan; Roche Diagnostics, Indianapolis, IN) that targets the 5' UTR. For plasma specimens, the MultiCode assay had a limit of detection of 2.3 log10 IU/ml and a linear range of at least 6.7 log10 IU/ml. Comparison of plasma viral loads obtained by the MultiCode and TaqMan tests showed that they were in very close agreement (mean difference, -0.1 log10 IU/ml). No genotype bias was observed for genotypes 1, 2, and 3. When the MultiCode assay was evaluated with the MagNA Pure and easyMAG extraction methods, the viral loads for the easyMAG extraction were consistently higher for all specimens tested (mean difference, 0.45 log10 IU/ml). Aside from the limit of detection, the performance characteristics of the MultiCode assay were similar to the TaqMan assay for the clinical application of HCV load testing.

Clinical significance of quantitative monitoring and mutational analysis of BCR-ABL1 transcript in Philadelphia chromosome positive B lymphoblastic leukemia.

Quantitative detection of BCR-ABL1 transcript is essential in monitoring residual disease of Philadelphia chromosome positive B lymphoblastic leukemia (Ph+ B-LL). We studied the kinetics of BCR-ABL1 transcript in 41 Ph+ B-LL patients in correlation with their clinical outcome. A total of 23 patients achieved complete molecular remission at 6 months post-treatment. This was associated with a lower relapse risk and better overall survival. Likewise, sustainable complete molecular remission in 27 patients was associated with superior clinical outcome. Sporadic low level BCR-ABL1 was detected in 12 of 27 patients who had attained complete molecular remission. The relapse rate was significantly higher in non-transplant patients with persistent positive BCR-ABL1 than patients transplanted when BCR-ABL1 was detectable. All eight patients harboring ABL1 kinase domain mutations died of disease or were transferred to hospice care. We concluded that monitoring the level of BCR-ABL1 transcript after hematologic remission has predictive value to the long-term outcome.