Infections and risk factors for infection-related mortality after pediatric allogeneic hematopoietic stem cell transplantation in Mexico: A single center retrospective study.

OBJECTIVE: To identify the type of infections and risk factors for infection-related mortality (IRM) after allogeneic hematopoietic stem cell transplantation (HSCT). METHODS: Retrospective cohort study of patients <16 years of age treated in 2010-2019 was conducted. Unadjusted hazard ratios (HR) and adjusted hazard ratios (aHR) with 95% confidence intervals (95% CIs) were estimated using Cox regression. Cumulative incidence was calculated. RESULTS: Data for 99 pediatric patients were analyzed. The myeloablative conditioning was the most used regimen (78.8%) and the hematopoietic stem cell source was predominantly peripheral blood (80.8%). Primary graft failure occurred in 19.2% of patients. Frequency of acute graft-versus-host disease was 46.5%. Total of 136 infectious events was recorded, the most common of which were bacterial (76.4%) followed by viral infection (15.5%) and then fungal infection (8.1%). The best predictors for infection subtypes where the following: a) for bacterial infection (the age groups of 10.1-15 years: aHR = 3.33; 95% CI: 1.62-6.85 and. >15 years: aHR = 3.34; 95% CI: 1.18-9.45); b) for viral infection (graft versus host disease: aHR = 5.36; 95% CI: 1.62-17.68), however, for fungal infection statistically significant predictors were not identified. Related mortality was 30% (n = 12). Increased risk for infection-related mortality was observed in patients with unrelated donor and umbilical cord stem cells recipients (HR = 3.12; 95% CI: 1.00-9.85). CONCLUSIONS: Frequencies of infections and infection-related mortality appear to be similar to those reported. Unrelated donors and stem cells from umbilical cord recipients were associated with a high risk of mortality.

Cord blood banking and transplantation at the Mexican Institute of Social Security: the first 5 years.

BACKGROUND: In January 2005, the Cord Blood Bank (CBB) at the Mexican Institute of Social Security initiated activities. Herein, we describe the experience generated during this period (January 1, 2005-December 31, 2009). STUDY DESIGN AND METHODS: Good manufacturing practices and standard operating procedures were used to address donor selection, as well as umbilical cord blood (UCB) collection, processing, and cryopreservation. Based mainly on HLA and nucleated cell content, specific UCB units were thawed, processed, and released for transplantation. RESULTS: A total of 589 UCB units were stored, representing 54% of the total number of units collected. Forty-eight units (8.14% of the stored units) were released for transplantation of 36 patients. Twenty-six patients (72% of cases) corresponded to patients with acute leukemia, five (14%) to patients with marrow failure, and the rest (five; 14%) to patients with hemoglobinopathies and other syndromes. The median number of nucleated cells infused per patient was 6.71 × 10(7) /kg and the median number of CD34+ cells was 4.8 × 10(5) /kg. Current engraftment data indicate that engraftment occurred in 56%, and no engraftment in 44%, of cases. Engraftment was more frequent (59%) in patients that received more than 3 × 10(7) total nucleated cells (TNCs)/kg body weight, than in those receiving fewer than 3 × 10(7) TNCs/kg (40%). Myeloid engraftment was observed 7 to 54 days posttransplant (median, 23 days), whereas platelet engraftment was detected on Days 12 to 87 posttransplant (median, 38 days). To date, the disease-free survival rate was 41% and the overall survival was 47%, with survival periods of 126 to 1654 days. CONCLUSION: Although the experience presented herein is still limited and the period of analysis is still short, the results obtained during these 5 years are encouraging.

The age incidence of childhood B-cell precursor acute lymphoblastic leukemia in Mexico City.

The objective of this population-based survey was to assess the peak age of incidence of B-cell precursor acute lymphoblastic leukemia (ALL) in children in Mexico City (MC). All patients were classified according to their immunophenotype, and only B-cell precursor and T-lineage were analyzed. Rates of incidence were calculated x10 children. Of the 364 children from MC who were included in this study, immunophenotyping had been performed for 81.6%. The frequency of B-cell precursor ALL was 76.1%, whereas T lineage ALL showed a frequency of 23.6%. Peak age for ALL was 2 to 3 years of age. B-cell precursor ALL was the major contributor to peak age; T lineage ALL showed a peak among 1 and 3 years of age. We conclude that the age peak for children with ALL in MC is within the ranges reported for developed countries and that B-cell precursor ALL is the main contributor to these peak.

Frecuencia de hemorragia intracraneana en niños hemofílicos / Intracranial hemmorrhage frequency in patients hemophilic

La hemorragia intracraneana es la principal causa de muerte entre los pacientes hemofílicos. Por esta razón se revisaron 75 expedientes clínicos de pacientes menores de 16 años con el diagnóstico de hemofilia. Se encontraron seis niños con hemorragia intracraneana (HIC). El tiempo de inicio de la sintomatología fue de 12 h hasta cuatro días con una media de 39 h. Los signos y síntomas encontrados fueron: cefalea, vómito, crisis convulsiva, hematoma en el sitio del traumatismo, hemiperesia corporal izquierda, nistagmus, náusea. Se dio tratamiento substitutivo en todos los niños. Cuatro presentaron secuelas neurológicas. La frecuencia de HIC se estimó en 8 por ciento de los hemofílicos. Se concluye que para prevenir la muerte y minimizar las secuelas, una terapia de reemplazo adecuada, ésta debe ser instituida tan pronto como se sospecha el sangrado o inmediatamente después del traumatismo craneoencefálico

Alteraciones citogenéticas en niños con leucemia aguda no linfoblástica / Cytogenetic defects in children with acute non-limphoblastic leukemia

Se realizó en 16 niños con leucemia aguda no linfoblástica estudio citogenético de la médula ósea por medio de dos métodos para la obtención de cariotipo para su análisis cromosómico: el método directo y el de cultivo de 48 horas. La investigación tuvo como objeto conocer las alteraciones citogenéticas en la población, debido al origen clonal de la enfermedad. Estas son útiles para valorar la remisión de la enfermedad y la respuesta al tratamiento, a la vez que permite dar un pronóstico