Evidence of spatial clustering of childhood acute lymphoblastic leukemia cases in Greater Mexico City: report from the Mexican Inter-Institutional Group for the identification of the causes of childhood leukemia.

Background: A heterogeneous geographic distribution of childhood acute lymphoblastic leukemia (ALL) cases has been described, possibly, related to the presence of different environmental factors. The aim of the present study was to explore the geographical distribution of childhood ALL cases in Greater Mexico City (GMC). Methods: A population-based case-control study was conducted. Children <18 years old, newly diagnosed with ALL and residents of GMC were included. Controls were patients without leukemia recruited from second-level public hospitals, frequency-matched by sex, age, and health institution with the cases. The residence address where the patients lived during the last year before diagnosis (cases) or the interview (controls) was used for geolocation. Kulldorff's spatial scan statistic was used to detect spatial clusters (SCs). Relative risks (RR), associated p-value and number of cases included for each cluster were obtained. Results: A total of 1054 cases with ALL were analyzed. Of these, 408 (38.7%) were distributed across eight SCs detected. A relative risk of 1.61 (p<0.0001) was observed for the main cluster. Similar results were noted for the remaining seven ones. Additionally, a proximity between SCs, electrical installations and petrochemical facilities was observed. Conclusions: The identification of SCs in certain regions of GMC suggest the possible role of environmental factors in the etiology of childhood ALL.

Maternal and paternal ages at conception of index child and risk of childhood acute leukaemia: A multicentre case-control study in Greater Mexico City.

BACKGROUND: The parental age at conception has been reported to be a risk factor for childhood acute leukaemia (AL); however, the relationship is controversial. The aim of the present study was to investigate the association between parental age at conception and the risk of AL in Mexican children, a population with a high incidence of the disease and a high prevalence of pregnancies in adolescents and young adults. METHODS: A multicentre case-control study was conducted. Incident AL cases younger than 17 years of age diagnosed between 2010 and 2015 were included. Controls were matched with cases according to age, sex, and health institution. Using logistic regression analysis, adjusted odds ratios (aOR) and 95 % confidence intervals (95 % CI) were calculated for each maternal stratum after adjusting for paternal age at conception of index child. The maternal age between 25 and 29.99 years was selected as the reference category. RESULTS: In most strata where maternal and paternal ages were assessed, no association was found with the risk of developing acute lymphoblastic leukaemia (ALL) and acute myeloid leukaemia (AML) in their offspring. An increased risk for AML was observed when the mother was between 20 and 24.99 years of age and the father aged 25-29.99 years (aOR, 1.94; 95 % CI, 1.03-3.67). In addition, there was a positive association for ALL when the mother´s age was between 20 and 24.99 years and the father was <20 years of age, however, a very wide confidence interval was noted (aOR, 12.26; 95 % CI, 1.41-106.83). CONCLUSION: In the present study, maternal and paternal ages assessed in different strata showed little association with risk of developing ALL and AML in children. Positive associations between risk of both types of childhood AL were observed with younger paternal and maternal ages.

A greater birthweight increases the risk of acute leukemias in Mexican children-experience from the Mexican Interinstitutional Group for the Identification of the Causes of Childhood Leukemia (MIGICCL).

In Mexico, due to the high rates of diabetes, overweight, and obesity, there has also been noted an increased newborn weight, which may be contributing to the elevated incidence rate of childhood acute leukemia (AL). We conducted a case-control study in public hospitals of Mexico City aimed to know whether a greater weight at birth is associated with a higher risk of developing leukemia. We included incident cases with acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML) diagnosed between 2010 and 2015. Controls were frequency-matched to the cases by age, sex, and health institution. Logistic regression analysis was performed adjusting risks by child's sex, overcrowding index, birth order, and mother's age at the time of pregnancy. Adjusted odds ratios (aORs) and 95% confidence intervals were calculated. A total of 1455 cases and 1455 controls were included. An evident association between ALL and child's birthweight ≥2500 g was found (aOR 2.06; 95% CI: 1.59, 2.66) and also, in those with birthweight ≥3500 g (aOR 1.19; 95% CI: 1.00, 1.41). In AML patients with birthweight ≥2500 g and ≥3500 g, an aOR of 1.77 (95% CI: 1.07, 2.94) and 1.42 (95% CI: 1.03-1.95) was observed, respectively. No association was noticed with either type of AL and a birthweight ≥4000 g. To sum up, we found a moderate association between not having a low birthweight and an increased risk of acute leukemias. Birthweight ≥3500 g was also a risk factor for both types of leukemia. This suggests that a greater birthweight may increase the risk of acute leukemias in Mexican children.

Apendicitis en la etapa pediátrica: correlación clínico-patológica / Appendicitis in pediatric age: clinico-pathologic correlation

Introducción. En apendicitis, los cirujanos realizan una clasificación basada en el aspecto macroscópico de la pieza quirúrgica; sin embargo, el patólogo reporta el diagnóstico histopatológico final, que en ocasiones puede diferir con el primero. Objetivo: comparar la clasificación macroscópica de la apendicitis aguda elaborada por el cirujano con el diagnóstico histopatológico del patólogo. Material y métodos. Estudio observacional, retrospectivo y retrolectivo que consistió en revisar los expedientes de niños con diagnóstico de apendicitis aguda y que fueron intervenidos quirúrgicamente en un período de 4 años y medio. Se analizaron: edad, sexo, cuadro clínico, estudios de laboratorio y radiológicos, el diagnóstico postoperatorio del cirujano y se comparó con el diagnóstico histopatológico. Análisis estadístico: frecuencias, medias y desviación estándar. Resultados. Se revisaron 311 expedientes. La edad de los pacientes fue de 10 ± 2 años (media ± desviación estándar), predominando el sexo masculino (56.2%), relación masculino/femenino de 1.2:1. Los principales signos o síntomas fueron: dolor abdominal 100%, vómito 81.3%, y fiebre 57.5%, con 1.9 ± 1.5 días de evolución del cuadro clínico. En la biometría hemática 83.9% presentaron leucocitosis, neutrofilia 98% y bandemia 53.6%. Los estudios radiológicos mostraron niveles hidroaéreos en 53.7% y borramiento del psoas en 44%. El diagnóstico postoperatorio del cirujano fue apéndice normal en 4.8%, apendicitis aguda fase I en 1 1.2%, fase II en 25.7%, fase III en 12.2% y fase IV en 45.9%. El diagnóstico histopatológico fue: normal 0.9%, incipiente 4.1 %, edematosa 8.3%, fibrinopurulenta 25.7%, necrótica 15.7%, perforada 41.4%, abscedada 58.1 %, con peritonitis 80.7%, presencia de fecalito 31.8%, hiperplasia folicular 6.1 % y adenitis mesentérica en 3.2%. Conclusión. La correlación del grado de apendicitis entre el cirujano y el patólogo es buena, aunque en algunos casos el cirujano califica a la apendicitis con menos gravedad que el patólogo, pero no hay repercusión en mayor número de complicaciones.

Introduction.The surgeon has a classification for appendicitis based in a macroscopic view, but the pathologist reports the histopathologic features. Sometimes there are differences between those classifications. Objective: to compare the clinic macroscopic appendicitis classification with the histopatologic classification. Material and methods. Design: in a retrospective study, we reviewed the charts of children with the diagnosis of appendicitis in a 4 year and a half period. We analyze the age, sex, clinical picture, hematic cytology, x ray studies, complications, use of antibiotics, and compare the clinical diagnosis of the surgeons against the diagnosis of pathologist. Results.We reviewed 31 1 charts. The patient's age was 10 ± 12 years (mean ± sd), 56.2% were male, male/female ratio 1.2:1.The clinical picture was abdominal pain in 100%, vomiting in 81.3% and fever in 57.5% with 1.9 ± 1.5 days of evolution. In the hematic cytology 83.9% of they presented leucocytosis, neutrofilia in 98% and bandemia in 53.6%.The x ray findings were intestinal ileus 53.7% and psoas erased in 44%. The surgeon diagnosis was; normal appendices in 4.8%, acute appendicitis grade I en 1 1.2%, II in 25.7%, III in 12.2% and grade IV in 45.9%. In the hystopatologic diagnosis; normal 0.9%, incipient 4.1%, phlegmonous 8.3%, fibrin purulent 25.7%, gangrenous 15.7%, perforated 45.9%, with abscess 58.1 %, with peritonitis 80.7%, fecalith 3 1.8%, follicular hyperplasic 6.1 % and mesenteric adenitis in 3.2%. Conclusion. The correlation of the grade of appendicitis between the surgeon and the pathologist is good, however in any cases the surgeon underrated the grade of gravity of the appendicitis than the pathologist, but there are not more cases complicated.