Impact of maternal pre-pregnancy overweight on infant overweight at 1 year of age: associations and sex-specific differences

BACKGROUND

Maternal overweight or obesity (OWOB) is linked to gestational diabetes, fetal macrosomia and higher rates of caesarean delivery.

OBJECTIVES

The study aims to assess whether maternal pre-pregnancy OWOB is associated with infant overweight in a sex-dependent manner, independent of microbiota-altering variables.

METHODS

Weight and length measurements of 955 mother-infant pairs were obtained from the Canadian Healthy Infant Longitudinal Development cohort. Maternal pre-pregnancy weight was defined as follows: normal, overweight (25 ≤ body mass index < 30) and obese (body mass index ≥ 30). Age and sex-adjusted weight-for-length z-scores >97th percentile were classified as infant overweight at age 1 year. Associations between pre-pregnancy and infant overweight were determined by linear and logistic regression, adjusting for covariates.

RESULTS

Maternal pre-pregnancy OWOB were associated with infant weight-for-length and overweight risk at 1 year. Except for pre-pregnancy obesity, these associations were not attenuated appreciably after adjustment for birth mode, exclusivity of breastfeeding, exposure to antibiotics and infant sex. Yet only boys born to mothers with obesity were three times more likely to become overweight at age 1 independent of microbiota-altering variables. Pre-pregnancy obesity was associated with weight-for-length in male and female infants.

CONCLUSIONS

Maternal pre-pregnancy OWOB increases the risk of infant overweight, and this association is more evident in male infants.

Misdiagnosis of asthma in schoolchildren

BACKGROUND

A correct diagnosis of asthma is the cornerstone of asthma management. Few pediatric studies have examined the accuracy of physician-diagnosed asthma.

OBJECTIVES

We determined the accuracy of parent reported physician-diagnosed asthma in children sampled from a community cohort.

METHODS

Nested case-control study that recruited 203 children, aged 9-12, from a community-based sample. Three groups were recruited: asthma cases had a parental report of physician-diagnosed asthma, symptomatic controls had respiratory symptoms without a diagnosis of asthma, and asymptomatic controls had no respiratory symptoms. All participants were assessed and assigned a clinical diagnosis by one of three study physicians, and then completed spirometry, methacholine challenge, and allergy skin testing. The reference standard of asthma required a study physician's clinical diagnosis of asthma and either reversible bronchoconstriction or a positive methacholine challenge. Diagnostic accuracy, sensitivity and specificity were calculated for parent-reported asthma diagnosis compared to the reference standard.

RESULTS

One hundred two asthma cases, 52 controls with respiratory symptoms but no asthma diagnosis, and 49 asymptomatic controls were assessed. Physician agreement for the diagnosis of asthma was moderate (kappa 0.46-0.81). Compared to the reference standard, 45% of asthma cases were overdiagnosed and 10% of symptomatic controls were underdiagnosed. Parental report of physician-diagnosed asthma had 75% sensitivity and 92% specificity for correctly identifying asthma.

CONCLUSIONS

There is significant misclassification of childhood asthma when the diagnosis relies solely on a clinical history. This study highlights the importance of objective testing to confirm the diagnosis of asthma. Pediatr Pulmonol. 2017;52:293-302. © 2016 Wiley Periodicals, Inc.

Impact of maternal intrapartum antibiotics, method of birth and breastfeeding on gut microbiota during the first year of life: a prospective cohort study

OBJECTIVE

Dysbiosis of the infant gut microbiota may have long-term health consequences. This study aimed to determine the impact of maternal intrapartum antibiotic prophylaxis (IAP) on infant gut microbiota, and to explore whether breastfeeding modifies these effects.

DESIGN

Prospective pregnancy cohort of Canadian infants born in 2010-2012: the Canadian Healthy Infant Longitudinal Development (CHILD) Study.

SETTING

General community.

SAMPLE

Representative sub-sample of 198 healthy term infants from the CHILD Study.

METHODS

Maternal IAP exposures and birth method were documented from hospital records and breastfeeding was reported by mothers. Infant gut microbiota was characterised by Illumina 16S rRNA sequencing of faecal samples at 3 and 12 months.

MAIN OUTCOME MEASURES

Infant gut microbiota profiles.

RESULTS

In this cohort, 21% of mothers received IAP for Group B Streptococcus prophylaxis or pre-labour rupture of membranes; another 23% received IAP for elective or emergency caesarean section (CS). Infant gut microbiota community structures at 3 months differed significantly with all IAP exposures, and differences persisted to 12 months for infants delivered by emergency CS. Taxon-specific composition also differed, with the genera Bacteroides and Parabacteroides under-represented, and Enterococcus and Clostridium over-represented at 3 months following maternal IAP. Microbiota differences were especially evident following IAP with emergency CS, with some changes (increased Clostridiales and decreased Bacteroidaceae) persisting to 12 months, particularly among non-breastfed infants.

CONCLUSIONS

Intrapartum antibiotics in caesarean and vaginal delivery are associated with infant gut microbiota dysbiosis, and breastfeeding modifies some of these effects. Further research is warranted to explore the health consequences of these associations.

TWEETABLE ABSTRACT

Maternal #antibiotics during childbirth alter the infant gut #microbiome.

The Canadian healthy infant longitudinal development birth cohort study: biological samples and biobanking

BACKGROUND

It is hypothesised that complex interactions between genetic and environmental factors give rise to allergy and asthma in childhood. The Canadian Healthy Infant Longitudinal Development (CHILD) study was designed to explore these factors.

METHODS

CHILD is a longitudinal, general population birth cohort study following infants from mid-pregnancy to age 5 years. Over this time period, biological samples, questionnaires, clinical measures and environmental data are collected.

RESULTS

A total of 3624 families have been recruited, and many thousands of samples and questionnaires have been collected, annotated, and archived. This report outlines the rationale and methodology for collecting and storing diverse biological samples from parents and children in this study, and the mechanisms for their release for analyses.

CONCLUSIONS

The CHILD sample and data repository is a tremendous current and future resource and will provide a wealth of information not only informing studies of asthma and allergy, but also potentially in many other aspects of health relevant for Canadian infants and children.

The effect of dornase alfa on ventilation inhomogeneity in patients with cystic fibrosis

Outcome measures to assess therapeutic interventions in cystic fibrosis (CF) patients with mild lung disease are lacking. Our aim was to determine if the lung clearance index (LCI) can detect a treatment response to dornase alfa in paediatric CF patients with normal spirometry. CF patients between 6-18 yrs of age with FEV(1 )≥ 80% pred were eligible. In a crossover design, 17 patients received 4 weeks of dornase alfa and placebo in a randomised sequence separated by a 4-week washout period. The primary end-point was the change in LCI from dornase alfa versus placebo. A mixed model approach incorporating period-dependent baselines was used. The mean ± sd age was 10.32 ± 3.35 yrs. Dornase alfa improved LCI versus placebo (0.90 ± 1.44; p = 0.022). Forced expiratory flow at 25-75% expired volume measured by % pred and z-scores also improved in subjects on dornase alfa (6.1% ± 10.34%; p = 0.03 and 0.28 ± 0.46 z-score; p = 0.03). Dornase alfa significantly improved LCI. Therefore the LCI may be a suitable tool to assess early intervention strategies in this patient population.

Inhaled mannitol identifies methacholine-responsive children with active asthma

Inhaled mannitol has been developed for bronchial challenge testing in adults. This study determined if mannitol could identify children with active asthma and responsive to methacholine, and whether mannitol challenge was faster to complete than methacholine challenge. Twenty-five children (aged 6-13 years) responsive to methacholine and 10 nonasthmatic children unresponsive to methacholine were studied. The methacholine challenge (Cockcroft protocol) was followed by a mannitol challenge on separate days. Twenty-one asthmatic children were positive to mannitol. Three taking inhaled corticosteroids with borderline methacholine responsiveness did not respond to mannitol, and one could not complete the mannitol challenge due to cough. The geometric mean (GM) and 95% confidence interval (CI) for PD(15) for mannitol was 39 mg (19, 78), and PC(20) for methacholine was 0.6 mg/mL (0.35-1.02) (r(p) = 0.75, p < 0.001, n = 21). Responses to mannitol were repeatable: GM PD(15) for the first challenge was 29 mg (CI: 17,50), and for the second challenge, 33 mg (CI: 20, 55) (P = 0.44, n = 9). Mannitol was faster to administer than methacholine (median (range)) 14 min (5-32) vs. 29 min (19-49), respectively (P < 0.001). Time to recover to baseline FEV(1) spontaneously and after bronchodilator administration was similar for both challenges. There were no significant falls in arterial oxygen saturations. During mannitol challenge, the mean (SD) fall in FEV(1) in nonasthmatic children was 3.1% (2.9). We conclude that mannitol identifies children with airway hyperresponsiveness and is faster to perform than the methacholine challenge.

Multiple urethral calculi in children: report of two cases

Multiple urethral calculi are rarely found in children. We report herein two unusual cases of children found to have multiple urethral calculi. In one, the calculi formed proximal to a stricture and in the other they formed within a diverticulum. Both patients required urethrotomy for removal of the calculi. A unique cause of urethral stricture is also described in case 1.

The association of sacrococcygeal teratoma with high anorectal and genital malformations

A rare case of sacrococcygeal teratoma in association with high anorectal malformation, proximal penile hypospadias and penoscrotal transposition is reported. No similar report has been found in the available English literature. The embryopathogenesis is being explained on the basis of existing knowledge.

Single-system cecoureterocele

A rare case of single system cecoureterocele associated with ipsilateral dysplastic kidney in a 4-year-old girl is reported. The preoperative radiological and endoscopic investigations identified ureterocele but not its cecal extension. The latter was diagnosed only during the transvesical surgery. Complete cure of her symptoms was achieved following staged procedures comprising of right ipsilateral nephroureterectomy followed by combined transvesical and transurethral deroofing of the cecoureterocele, excision of ureteric stump and its extension in the bladder and repair of the detrusor. This is the second case report in English language literature of single-system cecoureterocele.