Infantile hypertrophic pyloric stenosis: a review of 222 cases

Question of an infectious etiology or contribution to the pathogenesis of infantile hypertrophic pyloric stenosis

Infantile hypertrophic pyloric stenosis is a concerning cause of nonbilious vomiting in the neonatal population. Although a number of etiological theories exist, its exact cause remains nebulous. The question of an infectious etiology (or contribution) has been previously examined in case reports and case series, with recent support through suggestions of seasonality and familial aggregation with unclear inheritance patterns. The present review discusses the published literature regarding infectious etiologies of infantile hypertrophic pyloric stenosis. Furthermore, it attempts to demonstrate that newer research regarding an NOS1 genetic etiology does not exclude, but rather can be consistent with, an infectious etiology.

Use of macrolides in mother and child and risk of infantile hypertrophic pyloric stenosis: nationwide cohort study

OBJECTIVE

To assess the association between use of macrolide antibiotics in mothers and infants from pregnancy onset until 120 days after birth and infantile hypertrophic pyloric stenosis (IHPS).

DESIGN

Nationwide register based cohort study.

SETTING

Denmark, 1996-2011.

PARTICIPANTS

999,378 liveborn singletons and linked individual level information on macrolide prescriptions (maternal use during pregnancy, n=30,091; maternal use after birth, n=21,557; use in infants, n=6591), surgery for IHPS, and potential confounders.

MAIN OUTCOME MEASURES

Surgery for IHPS by three categories of macrolide use: in mothers during pregnancy, in mothers after birth, and in infants after birth.

RESULTS

880 infants developed IHPS (0.9 cases per 1000 births). Compared with infants with no use of macrolides, the adjusted rate ratio for IHPS in infants with use of macrolides during days 0 to 13 after birth was 29.8 (95% confidence interval 16.4 to 54.1) and during days 14 to 120 was 3.24 (1.20 to 8.74); the corresponding absolute risk differences were 24.4 (95% confidence interval 13.0 to 44.1) and 0.65 (0.06 to 2.21) cases per 1000 infants exposed to macrolides, respectively. The rate ratio for maternal use of macrolides for days 0 to 13 after birth was 3.49 (1.92 to 6.34) and for days 14 to 120 was 0.70 (0.26 to 1.90); the corresponding absolute risk differences were 2.15 (0.82 to 4.64) and -0.11 (-0.26 to 0.31). The rate ratios for maternal use of macrolides during pregnancy were 1.02 (0.65 to 1.59) for weeks 0 to 27 and 1.77 (0.95 to 3.31) for weeks 28 to birth; the corresponding absolute risk differences were 0.01 (-0.31 to 0.50) and 0.67 (-0.06 to 2.02).

CONCLUSIONS

Treatment of young infants with macrolide antibiotics was strongly associated with IHPS and should therefore only be administered if potential treatment benefits outweigh the risk. Maternal use of macrolides during the first two weeks after birth was also associated with an increased risk of IHPS. A possible association was also found with use during late pregnancy.

Is Helicobacter pylori a cause of infantile hypertrophic pyloric stenosis?

My hypothesis is that infantile hypertrophic pyloric stenosis (IHPS) is caused in some cases by Helicobacter pylori (HP) a bacterium commonly found in the human stomach. IHPS is an idiopathic condition of infancy. It occurs at about 5 weeks of age in 3 per 1000 newborns. Children with IHPS have structurally normal pylori at birth and do not resemble children with congenital anomalies. Some nonspecific evidence (temporal distribution, seasonality, familial clustering, leukocytic infiltrates, and increased risk with bottle feeding) are compatible with an infectious etiology. Some other epidemiologic features of IHPS, such as its strong male predominance, its racial and social class variation, and a possible drop in its incidence, are also features of HP infection. Clinical features of IHPS, such as vomiting, hematemesis, and esophagitis, are also consistent with HP. Finally, children with IHPS appear to be more likely to develop chronic conditions, such as peptic ulcers, now known to be caused by HP.

Evolution in the recognition of infantile hypertrophic pyloric stenosis

PURPOSE

To analyze changes in the clinical condition at presentation and methods of establishing the diagnosis of infantile hypertrophic pyloric stenosis (IHPS).

METHODS

Retrospective review of patients who underwent pyloromyotomy (PM) for suspected IHPS at two institutions from 1969 through 1994 was performed. For the purposes of comparison, the population was divided into five equal time periods.

RESULTS

Over the 25-year period, 901 infants underwent PM. Patients presented at a younger age, weighed more, and had a shorter length of illness in the most recent time period. Hypochloremic alkalosis was found half as frequently in the most recent time period compared to the earliest group. A palpable pyloric tumor was present in 79% of patients in the earliest time period compared with 23% in the most recent time period. Sixty-one percent of patients in the earliest group and 96% in the latest group underwent an imaging study, reflecting the referring physician's evaluation before referral to the surgeon.

CONCLUSIONS

Currently, patients with IHPS less frequently present with the clinical hallmarks of the disease. The use of imaging studies to establish the diagnosis has become common practice. The result has been the diagnosis of IHPS before alkalosis has developed, a shorter clinical course, less morbidity, and a shorter postoperative hospital stay.

Complications of pyloromyotomy for infantile hypertrophic pyloric stenosis

BACKGROUND

Few references exist regarding contemporary complications of pyloromyotomy (PM) for infantile hypertrophic pyloric stenosis (IHPS). Therefore, we reviewed the frequency and outcome of patients with IHPS who developed complications from PM.

METHOD

A 25-year retrospective review was performed in two populations. The first group included all infants who had a PM for IHPS at two pediatric surgery centers. The second group included all infants referred from other institutions who developed complications following PM for IHPS.

RESULTS

Between 1969 and 1994, 901 PMs were performed. Intraoperative complications occurred in 40 patients (4%), including 39 duodenal perforations and 1 difficult intubation requiring prolonged ventilation. No unrecognized duodenal perforations or incomplete PMs were found. Postoperative complications developed in 52 patients (6%). The wound infection rate was less than 1%. Postoperative vomiting occurred in 31 infants (3%). The mortality rate was 0.1%, with 1 death due to sepsis from delayed diagnosis of Hirschsprung's disease. During the same study period, 11 patients were referred from other hospitals for postoperative complications. Five had persistent vomiting treated successfully with expectant management. Six infants needed reoperation: 3 for persistent IHPS, 1 for gastric outlet obstruction, and 1 for small bowel obstruction secondary to adhesions; 1 required wound abscess drainage.

CONCLUSION

Pyloromyotomy is not without complications. Duodenal perforation should be infrequent, but when it occurs, it can usually be readily recognized and treated with minimal morbidity. Postoperative vomiting can be managed nonoperatively, but if it persists longer than 5 days, radiologic evaluation should be performed. Incomplete PM is uncommon and should not occur. A second myotomy is needed when the diagnosis of incomplete myotomy is established. A single standard of care should be expected of all surgeons who perform PM for IHPS.

Infantile hypertrophic pyloric stenosis: a clinical review from a general hospital

A review of 212 cases of infantile hypertrophic pyloric stenosis (IHPS) in a general hospital during an 8.5 year period documents clinical features and suggests refinement of treatment. Features such as sex, age at onset and presentation were similar to other studies. There was a preponderance of infants born in the summer. Premature infants represented 10% of the series, and the most premature (< 33 weeks gestation) presented later after birth (40 vs 25 days). Diagnosis was clinical in 65% of cases, but 4% presented before physical examination and diagnostic tests were positive. At the time of admission only 15% had significant abnormalities of serum electrolytes (chloride < 85 mmol/L). The periumbilical incision resulted in a hidden scar. Duodenal perforation (3.3%) and wound dehiscence (1.4%) are related to technical factors and can be avoided. The timing of commencement of postoperative feeds did not influence the rate of vomiting. The average length of stay was 3.5 days. These results are discussed with suggestions about how to minimize diagnostic tests and length of hospital stay.

Pyloric stenosis

Infantile pyloric stenosis is the most frequently encountered infant gastrointestinal obstruction in most general hospitals. Although the primary therapy for pyloric stenosis is surgical, it is essential to realize that pyloric stenosis is a medical and not a surgical emergency. Preoperative preparation is the primary factor contributing to the low perioperative complication rates and the necessity to recognize fluid and electrolyte imbalance is the key to successful anaesthetic management. Careful preoperative therapy to correct severe deficits may require several days to ensure safe anaesthesia and surgery. The anaesthetic records of 100 infants with pyloric stenosis were reviewed. Eighty-five per cent of the infants were male (i.e., 5.7:1 male to female ratio) 12% were prematures. Surgical correction was undertaken at an average age of 5.6 wk, and the average weight of the infants at the time of surgery was 4 kg. A clinical diagnosis of pyloric stenosis by history and physical examination alone was made in 73% of the infants presenting to The Hospital for Sick Children. All the infants received general anaesthesia for the surgical procedure and there were no perioperative deaths.