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.

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.

Abstract Clinical case description: A 61-year-old man with severe erectile dysfunction related to diabetes mellitus of long duration was treated through intracavernous stem cell application. Transplantation of autologous bone marrow stem cells through a single intracavernous injection was performed. Clinical response, Doppler ultrasound of the penis, and adverse events were evaluated during the 50-week follow-up. The highest clinical response was reported at week 12, but it diminished thereafter. At the end of follow-up, ultrasound identified the presence of neovascularization emerging from the cavernous arteries. Relevance: Numerous preclinical trials have demonstrated efficacy and safety, but there is insufficient clinical evidence showing promising results. Clinical implications: No adverse events were detected, and ultrasound revealed hemodynamic changes that were possibly related to the therapy. The source and dosage of stem cells, as well as subsequent therapeutic applications, pose questions that remain to be answered. Conclusions: Stem cell therapy for erectile dysfunction is a field of research that has sparked interest in numerous scientific groups, but clinical experience is still limited.

Resumen Descripción del caso clínico: Presentamos un masculino de 61 años con disfunción eréctil severa relacionada a diabetes mellitus de larga evolución manejado con células madre intracavernosas. Se realizó trasplante autólogo de células madre obtenidas de médula ósea en dosis única aplicadas vía intracavernosa. Se realizó un seguimiento de 50 semanas que evaluó la respuesta clínica, la ecografía doppler del pene y los eventos adversos. La respuesta clínica más alta se reportó en la semana 12, pero posteriormente disminuyó. Los hallazgos ecográficos revelaron la presencia de neovascularización que emerge de las arterias cavernosas al final del seguimiento. Relevancia: Numerosos estudios preclínicos han demostrado eficacia y seguridad. Se ha reportado evidencia clínica limitada que muestra resultados prometedores. Implicaciones clínicas: No se detectaron eventos adversos y la ecografía mostró cambios hemodinámicos, posiblemente relacionados con la terapia. Las aplicaciones posteriores, la fuente de células madre y la dosis siguen siendo preguntas sin responder. Conclusiones: La terapia con células madre para la disfunción eréctil es un campo que ha despertado el interés de numerosos grupos científicos. Sin embargo, la experiencia clínica sigue siendo limitada.