Lactate dehydrogenase as a hematopoietic stem cell mobilization biomarker in autologous transplantation

ABSTRACT Introduction: Pre-apheresis peripheral blood CD34+ cell count (PBCD34+) is the most important predictor of good cell mobilization before hematopoietic stem cell transplantation, albeit flow cytometry is not always immediately available. Identification of surrogate markers can be useful. The CD34+ cells proliferate after mobilization, resulting in elevated lactate dehydrogenase (LDH) activity and correlating with the PBCD34+ count. Objective: To determine the LDH cut-off value at which adequate CD34+ cell mobilization is achieved and its diagnostic yield. Materials and methods: A total of 103 patients who received an autologous stem cell transplantation (ASCT) between January 2015 and January 2020 were included. Demographic and laboratory characteristics were obtained, including complete blood count, pre-apheresis PBCD34+ and LDH levels. Receiver operating characteristic (ROC) curves were performed to identify the optimal serum LDH activity cut-off points for ≥ 2 and ≥ 4 × 106 cells/kg post-mobilization CD34+ count and their diagnostic yield. Results: A post-mobilization serum LDH cut-off value of 462 U/L yielded a sensitivity (Se) = 86.8% (positive predictive value [PPV] = 72.7%), a pre- and post-mobilization serum LDH difference cut-off value of 387 U/L, an Se = 45.7% (PPV = 97%) and an LDH ratio of 2.46, with an Se = 47.1% (PPV = 97%) for an optimal mobilization count (CD34+ ≥ 4 × 106). Conclusion: The LDH measurement represents a fast and affordable way to predict PBCD34+ mobilization in cases where flow cytometry is not immediately available. According to the LDH diagnostic yield, it could be used as a surrogate marker in transplant centers, supporting the CD34+ count, which remains the gold standard.

Real-world practice of acute leukemia intrathecal chemotherapy administration: A Mexican nationwide survey

ABSTRACT Introduction: Intrathecal chemotherapy is a mainstay component of acute lymphoblastic leukemia treatment. In Mexico, there is a considerable practice variability in aspects, such as the manner of preparation and the administration technique. Objective: Our objective was to describe the different techniques used for the application of ITC and review the existing recommendations in the literature. Method: A cross-sectional, nationwide survey study was conducted by an electronic questionnaire sent to hematologists and oncologists in Mexico. We collected demographic data, personal experience, intrathecal chemotherapy techniques, drug preparation and postprocedural conduct. Results: We received 173 responses. Twenty percent had an anesthesiologist administering sedation and pain management. The platelet count considered safe was 50 × 109/L in 48% of the participants. In 77% (n = 133) of the cases, the conventional needle with stylet used was, 49% did not receive any added diluent in the intrathecal chemotherapy and only 42% were recommended to rest in a horizontal position for more than 30 min. Conclusion: We identified a considerable variation in the administration of intrathecal chemotherapy across the hematologists in Mexico. We discuss the implications and opportunities in reducing the variation in our setting, highlighting the unmet need to establish guidelines that should be evaluated by the Mexican professional society to produce a position paper regarding practice standardization.

Bone marrow transplantation in a child with hemophagocytic lymphohistiocytosis using a less toxic conditioning regimen

Background. Hemophagocytic lymphohistiocytosis (HLH) is a rare non-neoplastic, frequently fatal disease of childhood. HLA-matched bone marrow transplantation (BMT) can bring about long-term remission and an eventual cure. Methods. We report on the beneficial effect of BMT in a 2-month-old male using a less intensive conditioning regimen. The regimen included busulfan at 4 mg/kg/day (total dose 16 mg/kg), etoposide at 300 mg/m²/day (total dose 900 mg/m²), and cyclophosphamide at 50 mg/kg/day (total dose 150 mg/kg). Prophylaxis for graft-vs.-host disease included methotrexate and cyclosporine. Results. An absolute neutrophil count of 500 µL was noticed on + day 12 (engraftment day). At present, i.e., 400 days after the procedure, the patients is asymptomatic, his physical examination is normal, and a slightly increased level of gamma-glutamyl-transpeptidase (GGT) and alkaline phosphatase are the only laboratory abnormalities. Conclusions. In this case, the conditioning regimen was adequate for the eradication of the disease and allowed persistent engraftment without significant toxicity. The results in our patient suggest that a less toxic regiment is feasible and permits rapid engraftment without compromising the effectiveness of chemotheraphy