Does exclusive breastfeeding confer protection against infantile hypertrophic pyloric stenosis? A 30-year experience in Benin City, Nigeria

Neonatal azithromycin administration to prevent infant mortality: study protocol for a randomised controlled trial

INTRODUCTION

Biannual mass azithromycin distribution to children aged 1-59 months has been shown to reduce all-cause mortality. Children under 28 days of age were not treated in studies evaluating mass azithromycin distribution for child mortality due to concerns related to infantile hypertrophic pyloric stenosis (IHPS). Here, we report the design of a randomised controlled trial to evaluate the efficacy and safety of administration of a single dose of oral azithromycin during the neonatal period.

METHODS AND ANALYSIS

The Nouveaux-nés et Azithromycine: une Innovation dans le Traitement des Enfants (NAITRE) study is a double-masked randomised placebo-controlled trial designed to evaluate the efficacy of a single dose of azithromycin (20 mg/kg) for the prevention of child mortality. Newborns (n=21 712) aged 8-27 days weighing at least 2500 g are 1:1 randomised to a single, directly observed, oral dose of azithromycin or matching placebo. Participants are followed weekly for 3 weeks after treatment to screen for adverse events, including IHPS. The primary outcome is all-cause mortality at the 6-month study visit.

ETHICS AND DISSEMINATION

This study was approved by the Institutional Review Boards at the University of California, San Francisco in San Francisco, USA (Protocol #18-25027) and the Comité National d'Ethique pour la Recherche in Ouagadougou, Burkina Faso (Protocol #2018-10-123). The findings of this trial will be presented at local, regional and international meetings and published in open access peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT03682653; Pre-results.

Infantile hypertrophic pyloric stenosis - Our experience and challenges in a developing country

BACKGROUND

This study aims to evaluate the experience and challenges in managing patients with infantile hypertrophic pyloric stenosis (IHPS).

PATIENTS AND METHODS

From January 2007 to December 2015, data from patients with IHPS were retrospectively acquired and analyzed using SPSS version 15. Pearson correlation used to assess linear relationships and Student t-test to compare means. P < 0.05 was taken as statistically significant. Results were expressed as percentages, means ± standard deviation and illustrated in tables and graphs.

RESULTS

Twenty-six cases were managed with the mean age at diagnosis of 49.16 ± 21.4 days. Mean birth weight was 3.7 kg and mean weight at presentation was 3.3 kg. Firstborn was affected in 29%; 91% were term deliveries; 9% were post-term; none was preterm; and 36% were exclusively breastfed. Mean duration of symptoms was 25.6 ± 18.9 days. Hyponatraemia was seen in 36%, hypokalaemia 37.5%, alkalosis 35% and hypochloraemia 62%. Mean pyloric tumour length was 22.85 ± 6.56 mm and pyloric wall thickness 5.51 ± 1.36 mm. There was a significant correlation between duration of symptoms and serum potassium level (R = -0.6326, P = 0.002). Mean symptom duration in patients with hypokalaemia was 39.88 ± 23.41 days and without hypokalaemia 17.15 ± 9.78 days (P = 0.006). Mean hospital stay was 9.45 ± 3.27 days. Four patients developed four complications and three patients died (11.5%). Mean age at presentation for pre-operative mortalities was 84 ± 39 days and 46 ± 17.98 days for others (P = 0.015).

CONCLUSIONS

IHPS presents late in our environment and occurs mainly in term males. There is a significant positive relationship between duration of symptoms and serum potassium level and the mean duration of symptoms was significantly longer in those with hypokalaemia. Pre-operative mortality was significantly associated with longer duration of symptoms.

Formula-feeding and hypertrophic pyloric stenosis: is there an association? A case-control study

BACKGROUND

The etiology of infantile hypertrophic pyloric stenosis (HPS) is not fully understood. The objective of this study was to determine whether formula-feeding is associated with increased incidence.

METHODS

This case-control study included HPS cases and controls admitted between 1992 and 2012. Demographic data including feeding method were collected from patient charts and analyzed.

RESULTS

We identified 882 HPS cases and 955 controls. The highest incidence of HPS presentation was in summer (P=0.0028). Infants with HPS were more likely to have been exclusively formula-fed, have a family history of HPS, and be male compared to infants in the control group (P<0.001); they were also more likely to live in rural areas, although not significantly so. After adjusting for family history, sex, place of residence, and season of presentation, exclusively formula-fed infants were 1.36 times more likely to develop HPS compared with exclusively breastfed infants (RR 1.36, 95% CI 1.18-1.57, P<0.005).

CONCLUSIONS

Formula-feeding is associated with significantly increased risk of HPS. Further investigation may help to determine the components of formula that simulate hypertrophy of the pylorus muscle, or the components of breast milk that are protective, as well as other influencing factors.

LEVEL OF EVIDENCE

3b.

Infantile hypertrophic pyloric stenosis at a tertiary care hospital in Tanzania: a surgical experience with 102 patients over a 5-year period

Background

Infantile hypertrophic pyloric stenosis (IHPS) is the most common cause of gastric outlet obstruction in infants. There is paucity of published data regarding this condition in our setting. This study describes the clinical presentation, mode of treatment and outcome of treatment of this disease and identifies factors responsible for poor outcome of these patients.

Methods

This was a descriptive retrospective study of infants with HPS admitted to Bugando Medical Centre and subsequently underwent surgery between February 2009 and January 2014.

Results

A total of 102 patients (M:F = 4.7:1) were studied. The median age at presentation was 5 weeks. The median duration of illness was 4 weeks. Fifty-four (52.9 %) patients occur in first-born children. Associated anomalies were reported in 7 (6.9 %) patients. Non-bilious vomiting was the most frequent symptom and it was described in all (100 %) patients. A palpable mass was found in 23.5 % of infants. The diagnosis of IHPS was made clinically in 86 (84.3 %) and by ultrasound in 16 (15.7 %) patients. The treatment was Ramstedt’s pyloromyotomy in all cases. There were 6 (5.9 %) intra-operative mucosal perforations which were repaired successively. Postoperative complication was 11.8 %. The median length of hospital stay was 12 days and it was significantly associated with prolonged pre-operative hospitalization (p = 0.001). The mortality rate was 4.9 %. Age below 2 weeks, late presentation (≥14 days), severe dehydration on admission, hypokalaemia on admission and surgical site infection were the main predictors of mortality (p < 0.001).

Conclusion

This study has shown that IHPS is a common condition in our setting. Age <2 weeks, delayed presentation, prolonged preoperative hospital stay, surgical site infection and high proportion of dehydration and electrolyte disturbance were the main predictors of poor outcome. A high index of suspicion is needed in infants with non-bilious vomiting to avoid delay in diagnosis.

Bottle-feeding and the Risk of Pyloric Stenosis

OBJECTIVES

Bottle-feeding has been suggested to increase the risk of pyloric stenosis (PS). However, large population-based studies are needed. We examined the effect of bottle-feeding during the first 4 months after birth, by using detailed data about the timing of first exposure to bottle-feeding and extensive confounder information.

METHODS

We performed a large population-based cohort study based on the Danish National Birth Cohort, which provided information on infants and feeding practice. Information about surgery for PS was obtained from the Danish National Patient Register. The association between bottle-feeding and the risk of PS was evaluated by hazard ratios (HRs) estimated in a Cox regression model, adjusting for possible confounders.

RESULTS

Among 70148 singleton infants, 65 infants had surgery for PS, of which 29 were bottle-fed before PS diagnosis. The overall HR of PS for bottle-fed infants compared with not bottle-fed infants was 4.62 (95% confidence interval [CI]: 2.78-7.65). Among bottle-fed infants, risk increases were similar for infants both breast and bottle-fed (HR: 3.36 [95% CI: 1.60-7.03]), formerly breastfed (HR: 5.38 [95% CI: 2.88-10.06]), and never breastfed (HR: 6.32 [95% CI: 2.45-16.26]) (P = .76). The increased risk of PS among bottle-fed infants was observed even after 30 days since first exposure to bottle-feeding and did not vary with age at first exposure to bottle-feeding.

CONCLUSIONS

Bottle-fed infants experienced a 4.6-fold higher risk of PS compared with infants who were not bottle-fed. The result adds to the evidence supporting the advantage of exclusive breastfeeding in the first months after birth.

Hypertrophic pyloric stenosis in the Third World

The relative rarity of hypertrophic pyloric stenosis (HPS) in the developing world makes its diagnosis a challenge to many physicians. This study audits the management of HPS at a tertiary hospital in South Africa, with a view to defining its regional pattern. This is a retrospective review of records of all patients ( n = 63) managed for HPS over an eight-year period (2002–2010). The mean age at presentation was 6.2 weeks and the male/female ratio was 6:1. The majority of patients presented with non-bilious vomiting. Abdominal ultrasound had a sensitivity of 65% and 81.3% when the criteria of pyloric muscle thickness >4 mm and pyloric channel length >16 mm were used, respectively. The overall complication rate was 14.3% and the mortality rate was 0%. Despite the rarity of HPS in the Third World, the outcome of its management is favourable. However, the sensitivity of abdominal ultrasound for diagnosing HPS is low.

Epidemiological features of infantile hypertrophic pyloric stenosis in Taiwanese children: a Nation-Wide Analysis of Cases during 1997-2007

Objective

To describe the epidemiological characteristics of infantile hypertrophic pyloric stenosis (IHPS) in ethnic Chinese children.

Materials and Methods

We reviewed the National Health Insurance claims database and analyzed data from children less than one year of age who had been diagnosed with IHPS (ICD-9-CM 750.5) and had undergone pyloromyotomy (ICD-9-CM 43.3). We analyzed the incidence, gender, age at diagnosis, length of hospital stay, seasonal variation and cost of IHPS from data collected between January 1997 and December 2007.

Results

A total of 1,077 infants met inclusion criteria, including 889 boys and 188 girls. The annual incidence of IHPS ranged from 0.30 to 0.47 per 1,000 live births with a mean incidence of 0.39 per 1,000 live births. Between 2002 and 2007, the incidence showed a declining trend (P = 0.025) with coincidentally increasing trends for both exclusive breastfeeding (P = 0.014) and breastfeeding plus bottle feeding (P = 0.004). The male-to-female rate ratio was dynamic and increased from 3.03 during the first two weeks of life to 8.94 during the 8^th through 10^thweeks of life. The overall male-to-female rate ratio was 4.30. The mean age at diagnosis was 43.1±2.4 days. After analyzing the months of birth and hospital admission, no seasonal variation associated with IHPS was detected. The mean length of hospital stay was 8.28±7.10 days.

Conclusions

The incidence of IHPS in Taiwan, a country with a majority ethnic Chinese population, was lower than observed incidences in Caucasian populations living in Western countries. Breastfeeding campaigns and low maternal smoking rates may contribute to the lower incidence of IHPS in Taiwan. However, additional studies with longer follow-up periods are needed.