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.

[Volvulus of the vermiform appendix. A case report]

BACKGROUND

Vermiform appendix torsion is a very rare condition, with only 25 cases recorded in the international literature. This patient is the second case registered in our country.

CLINICAL CASE

A seven year-old female patient suddenly developed crampy central abdominal pain that gradually localized in the right lower quadrant. She had vomiting, but no fever. On examination there were acute abdominal signs and during surgical exploration vermiform appendix torsion was founded. The patient underwent appendectomy with an uneventful recovery.

[Is the risk of death real among home accidents?]

Descriptive study on damage to children's health caused by accidents. The literature has mainly focused on the analysis of severe trauma. The main objective was to assess the morbidity and mortality based on the authors experience and to propose special measures to prevent this type of trauma. Home accidents are a frequent form of pediatric trauma, yet reports in the literature are not always consistent with its real prevalence. We believe that home traumatic events have been underestimated and neglected mainly because they are generally not a cause of death, especially among infants. We analyzed 21 patients who underwent a traumatic lesion at home.

[Fibromatosis infantile. Report of an aggressive disease]

This rare entity is characterized by multiple nodular lesions largely composed of collagen-forming spindle cells and involving the subcutis, skeletal muscle, bone and viscera of newborns and infants that occurs in either a solitary or multicentric form. The clinical course of a case is presented. The patient is a 2-year-old male who was brought to our hospital because of a large cervical mass. On physical examination a firm, subcutaneous, immobile painless mass measuring 4.5x6 cm was palpated at right side of neck. After the first admission, 13 complete surgical resections were performed. This patient is the eleventh familial case in the literature. The patient died 10 years after the first surgery.

[Appendicitis in a two-months old infant with a peritoneovaginal duct]

Acute appendicitis in infants is a very unusual disease, but associated to structural defects like patent peritoneovaginal duct, Meckel's diverticulum, clubfeet, and Moebius syndrome is extremely rare. Case report. A male of two months-old with this association is presented. Left inguinal swelling and acute abdomen syndrome were identified. In laparotomy, iguinal defect and a gangrenous appendicitis were observed. Appendectomy was performed and postoperative recovery was unevenful.

[Inguinal symptoms of acute abdomen]

INTRODUCTION

We describe a syndrome in which empty hernial sac, in its role of peritoneal recess, becomes distended with pus during or after general peritonitis, usually caused by acute appendicitis. Until 1998, only 14 pediatric cases were described in the literature.

MATERIALS, METHODS, AND RESULTS

We presented here eight cases of patients who experienced inguinal symptoms. In four, appendectomy was performed; in four, this was secondary to necrotizing enterocolitis. Inguinal complaints, pain, and flogosis were present in first group, while pneumoperitoneum and visible duct vaginalis were present in second group.

CONCLUSIONS

These cases demonstrated that persistent patent processus vaginalis may predispose to inguinal pathology secondary to intraabdominal sepsis and represent a unique complication.

[Acute pancreatitis in childhood. Is it the same disease in adults?]

BACKGROUND

Acute pancreatitis in children is an uncommon, little known, poorly defined disease and thus is rarely considered in diagnosis of pediatric abdominal pain. It is rare but is being recognized more frequently, and differs from the disease in the adult both in etiology and therapeutic approach.

CLINICAL MATERIAL

Fifty children with acute pancreatitis were managed. Their history and postoperative course were analyzed in a retrospective study.

RESULTS

The clinical presentation was unremarkable; all patients had abdominal pain, specially in epigastrium, and vomiting was the only other clinical sign exhibited by > 80%. More than 40 biliary diseases were the cause of pancreatitis; trauma was the cause in 30%. Diagnosis could be difficult and unnecessary laparotomy was performed in 16 cases (32.0%) instances of suspected acute abdomen. Morbidity included sepsis, diabetic cetoacidosis, and pancreatic pseudocyst. Biliary disease is a frequent cause of both pediatric and adult pancreatitis. They are differences in clinical course and prognosis. In children, pancreatitis is usually confused with appendicitis.