Assessment of chimerism by next generation sequencing: A comparison to STR/qPCR methods.

Chimerism analysis is used to evaluate patients after allogeneic hematopoietic stem cell transplant (allo-HSCT) for engraftment and minimal measurable residual disease (MRD) monitoring. A combination of short-tandem repeat (STR) and quantitative polymerase chain reaction (qPCR) was required to achieve both sensitivity and accuracy in the patients with various chimerism statuses. In this study, an insertion/deletion-based multiplex chimerism assay by next generation sequencing (NGS) was evaluated using 5 simulated unrelated donor-recipient combinations from 10 volunteers. Median number of informative markers detected was 8 (range = 5 - 11). The limit of quantitation (LoQ) was determined to be 0.1 % recipient. Assay sample number/batch was 10-20 and total assay time was 19-31 h (manual labor = 2.1 h). Additionally, 50 peripheral blood samples from 5 allo-HSCT recipients (related: N = 4; unrelated: N = 1) were tested by NGS and STR/qPCR. Median number of informative markers detected was 7 (range = 4 - 12). Results from both assays demonstrated a strong correlation (Y = 0.9875X + 0.333; R2 = 0.9852), no significant assay bias (difference mean - 0.08), and 100 % concordant detection of percent recipient increase ≥ 0.1 % (indicator of increased relapse risk). NGS-based chimerism assay can support all allo-HSCT for engraftment and MRD monitoring and simplify clinical laboratory workflow compared to STR/qPCR.

Triple-Negative Lobular Breast Cancer Causing Hydronephrosis.

Breast cancer is the leading malignancy and the second most common cause of mortality in women. Although there have been advances in identifying biomarkers as potential targets for therapy, triple-negative breast cancer (TNBC) continues to have a poorer prognosis than the other receptor subtypes. The most common sites of metastasis are bone, liver, lung, and brain. We present a patient with known TNBC presenting with nausea and vomiting in whom computed tomography revealed a right-side pelvic mass causing hydronephrosis. Biopsy was consistent with TNBC of the ureter, an unusual site for breast cancer involvement. She required ureteral stent placement to relieve obstruction and has had good response to paclitaxel. Hydronephrosis due to malignancy presents significant risk of morbidity and mortality due to compromised renal function and must be resolved promptly to avoid compromise of renal function.

Antibiotic Use in Poultry Production in Grenada.

OBJECTIVE: Research is often lacking in low-income countries to substantiate the regulation of antibiotics in poultry production. Nonregulation of antibiotics in food animal industries has implications for human health. This study was conducted to provide an understanding of farmers' knowledge, attitudes, and practices regarding the use of antibiotics in poultry production in Grenada. METHOD: A cross-sectional study was conducted in August-September, 2016, surveying 30 poultry farmers each having 500 or more chickens grown for commercial purposes. RESULTS: More than 1000 birds were kept on 18 (60.0%) farms. Antibiotics were used on the majority of farms (25, 83.3%). More than half of the respondents, 19 (63.3%), stated they were only somewhat aware of issues related to the use of antibiotics and the majority, 21 (70.0%), were also unable to define antimicrobial resistance. There was inconsistency in the farmers' knowledge about how and when to use antibiotics. There was also a high level of noncompliance with manufacturers' recommendations for use of antibiotics. The respondents were not aware of local programs to monitor antibiotic use or manage antibiotic resistance in the poultry industry. CONCLUSION: Generally, the farmers' knowledge and practices were inconsistent with recommendations by the World Health Organization for antibiotic stewardship. While low-income countries, such as Grenada, are challenged with the lack of resources to undertake research and implement responsive actions, this research highlights the need for some immediate measures of remedy, such as education of farmers and monitoring procurement and use of antibiotics, to reduce risk to public health.