Gastro-oesophageal reflux and respiratory function in infants with respiratory symptoms

Pulmonary function in infants with swallowing dysfunction

BACKGROUND

Swallowing dysfunction can lead to recurring aspiration and is frequently associated with chronic symptoms such as cough and wheezing in infants. Our objective was to describe the characteristics of infants with swallowing dysfunction, determine if pulmonary function abnormalities are detectable, and if they improve after therapy.

METHODS

We studied 38 infants with a history of coughing and wheezing who had pulmonary function tests performed within two weeks of their diagnosis of swallowing dysfunction. The raised lung volume rapid thoracoabdominal compression technique was used. After 6 months of therapy, 17 of the infants repeated the tests.

RESULTS

Initially, 25 had abnormal spirometry, 18 had abnormal plethysmography, and 15 demonstrated bronchodilator responsiveness. Six months later test were repeated for seventeen patients. Ten patients had continued abnormal spirometry, two patients remained normal, three patients' abnormal spirometry had normalized, and two patients' previously normal studies became abnormal. Eight of the 17 patients had continued abnormal plethysmography, six had continued normal plethysmography, and three patients' normal plethysmography became abnormal. After 6 months of treatment, eight patients demonstrated bronchodilator responsiveness, of which five continued to demonstrate bronchodilator responsiveness and three developed responsiveness. The remainder either continued to be non- bronchodilator responsive (two) or lost responsiveness (three.) The findings of the abnormal tests in most infants tested is complicated by frequent occurrence of other co-morbidities in this population, including gastroesophageal reflux in 23 and passive smoke exposure in 13 of the infants.

CONCLUSIONS

The interpretation of lung function changes is complicated by the frequent association of swallowing dysfunction with gastroesophageal reflux and passive smoke exposure in this population. Six months of medical therapy for swallowing dysfunction/gastroesophageal reflux did not significantly improve pulmonary function in these infants. Long-term studies will be necessary to determine which of these changes persists into adulthood.

Hypopharyngeal and distal esophageal pH monitoring in children with gastroesophageal reflux and respiratory symptoms

PURPOSE

Fundoplication is frequently required for gastroesophageal reflux (GER)-related respiratory disease. Correlation between esophageal pH data and respiratory symptoms is poor but may be improved by monitoring hypopharyngeal pH. Reflux to the hypopharynx is underestimated by salivary bicarbonate. The aim of this study was to determine if hypopharyngeal pH monitoring using pH 4 and pH 5 as reflux thresholds could predict children with reflux-related respiratory disease.

METHODS

One hundred five children aged 4 months to 12 years underwent esophageal and hypopharyngeal pH monitoring. Hypopharyngeal pH data were analyzed using pH 4 and pH 5 as reflux thresholds. pH data from 4 groups were compared: group A, control group, no GER, no respiratory symptoms (n = 20); group B, respiratory symptoms, no GER (n = 16); group C, GER, no respiratory symptoms (n = 26); and group D, both GER and respiratory symptoms (n = 37).

RESULTS

Comparing groups C and D, there was no significant difference in hypopharyngeal pH data. Using pH 5 as the reflux threshold, children in group B refluxed to the hypopharynx significantly more frequently than controls. This was most evident in children with wheeze.

CONCLUSION

Hypopharyngeal pH monitoring does not differentiate children with GER and respiratory symptoms from those with GER alone and is therefore of doubtful value in diagnosing recurrent aspiration.

Severity of acid gastroesophageal reflux assessed by pH metry: is it associated with respiratory disease?

About 50% of children with chronic respiratory diseases (RD) have "silent" gastroesophageal reflux (GER). Our purpose was to evaluate the possibility that RD in patients with GER reflects the presence of more severe acid reflux. We compared the severity of parameters from pH studies in children with chronic RD and "silent" GER, to children with signs of symptomatic gastrointestinal (GI) GER with and without RD. This study included 236 children (aged 1 month to 15 years) with abnormal 24-hr pH monitoring among 718 patients studied for suspected diagnosis of GER. Patients were divided into three groups. Group 1 consisted of children with chronic RD but without any GI symptoms of GER. Group 2 was comprised of children with symptomatic GI presentation of GER such as regurgitation, vomiting, heartburn, and failure to thrive, but without any signs or symptoms of RD. Group 3 included children with prevalent RD and concomitant signs of symptomatic GER. Patients with predominant GI manifestations (group 2) had a significantly higher fraction of time with pH <4 (P < 0.01), total time value of pH <4 (P < 0.05), and longest episode with pH <4 (P < 0.05). Esophageal clearance was significantly longer in group 1 patients than in the other two groups (P < 0.05). Patients with mixed disease (group 3) were similar to patients in group 2. Patients with GI symptoms had significantly worse scores for all parameters evaluated except esophageal clearance score, compared to patients without GI symptoms. Longer esophageal clearance was the only parameter associated with respiratory signs in patients with respiratory symptoms compared to those without. In conclusion, the presence of RD in pediatric patients with silent GER is related to longer esophageal clearance, but is not related to severity of reflux.

Children with difficult asthma: a practical approach

Many open studies investigating the effects of innovative treatments for steroid-dependent asthma demonstrate some benefit. This is also true of the majority of placebo arms in placebo-controlled trials. This suggests that children with difficult asthma benefit from the high level of input that is typically provided in clinical trials, with or without additional medication. Such intensive management of patients, with the emphasis on establishing the diagnosis, improving adherence, and identifying provoking factors, is the key to optimizing asthma control for these children. For patients with genuinely severe asthma, despite high doses of conventional treatment, a greater understanding of the pathological basis of persistent symptoms is needed. Identification of different pathological subtypes of severe asthma should allow for more rational prescribing of asthma therapy, as well as the design of further trials of potential steroid-sparing treatments.

The relationship between gastroesophageal reflux and apnea in infants

OBJECTIVE

To determine the prevalence and relationship between apnea and gastroesophageal reflux (GER) among infants with apparent life-threatening events.

METHODS

We evaluated 67 infants of ages up to 6 months who had an idiopathic apparent life-threatening event as determined by polysomnography and pH monitoring.

RESULTS

No reflux (pH < 4 for more than 6 seconds) was evident in 32 infants. Fourteen others had such prolonged reflux that the relationship between apnea and reflux could not be evaluated. The 21 remaining infants who had episodes of apnea and reflux constituted the study group. In 81% of the apneic episodes, no relationship to GER was noted. Apnea preceded reflux in 93.6% of the episodes, and only 6.4% of the apneic episodes followed reflux. When apnea preceded reflux, the apnea was obstructive in 66.8% of episodes and mixed in 33.2%. Central apnea was not recorded preceding reflux.

CONCLUSIONS

Episodes of apnea were seldom associated with GER. However, in those instances when apnea and reflux were associated, the predominant sequence of events was obstructive apnea and to a lesser extent mixed apnea followed by reflux.

Gastroesophageal reflux and respiratory phenomena in infants: status of the intraluminal impedance technique

BACKGROUND

The coincidence of recurrent respiratory symptoms and gastroesophageal reflux (GER) is a well-known phenomenon in infants. Twenty-four-hour pH metry is the presumed gold standard of diagnostic tools for this symptom complex, but with this method, only acid (pH <4) and alkaline (pH >7) GER can be detected. Gastroesophageal reflux with an esophageal pH in the physiological range (pH 5-6.8) may represent many cases of clinically relevant GER unrecognized by pH metry. In this study the intraluminal multiple electrical impedance (IMP) procedure for complete registration of GER was compared with pH metry for its diagnostic value in the presence of respiratory symptoms.

METHODS

Twenty-two infants with recurrent regurgitation or pulmonary problems were investigated simultaneously with IMP, pH metry, and polygraphy during two feeding periods. Heart rate, oxygen saturation, sleep states, and oronasal flow were recorded, among other parameters.

RESULTS

Three hundred sixty-four occurrences of GER were detected by IMP; only 11.4% had a pH less than 4 and were therefore recognized by pH metry. Three hundred twelve (84.8%) occurrences were associated with breathing abnormalities, and 11.9% of these were detected by pH metry. Nineteen instances were accompanied by a decrease of oxygen saturation of more than 10% of the initial value. Only three (15.8%) of these had a pH less than 4. The remaining 16 reflux episodes were recognized by IMP only. After software-aided preselection, 165 instances of apnea were visually validated, 49 of which were accompanied by GER. Thirty-eight (77.6%) of these were exclusively recorded by IMP.

CONCLUSIONS

The use of pH metry alone cannot detect most GER incidents accompanied by respiratory symptoms and therefore does not appear to be suitable for this approach. The pH-independent IMP technique promises to be a reliable tool for presumably GER-associated respiratory symptoms.

Disorders of the oesophagus and stomach in infants

Pathological processes and disease entities in the upper gastrointestinal (GI) tract, specifically those of the oesophagus and the stomach in infancy, have received a disproportionately small amount of attention until recently when appreciation of their pathophysiology and concordant importance in terms of symptomatology has been highlighted. This is probably a phenomenon secondary to improved diagnostic yield from the recent technical advances in areas such as infant endoscopy and a shift in opinion regarding the pathophysiological origin of ubiquitous symptoms of infancy such as feeding disorders, colic and irritability. In addition, the apparently complex interactions of various aetiological factors such as pH-independent gastro-oesophageal reflux (GOR), cow's milk protein intolerance (CMPI), Helicobacter pylori gastritis and upper GI motor disorders have in the past 1-2 years become underlined in terms of aetiopathogenesis and have radically changed thinking regarding diagnosis and therapy of infants with apparent upper-GI-associated symptoms. The contribution to comprehension of infant upper GI disorders of inflammatory paradigms and ontogeny of the upper GI tract is also a recent area worthy of mention. The recent advances in all of these areas and their contribution to the understanding, and subsequent diagnosis and therapy, of upper GI symptoms and their explanation by way of aetiopathogenesis will be explored in this chapter.

Recent advances in pediatric nuclear medicine

This review is devoted to some controversial topics in the field of pediatric nuclear medicine. In most cases, drug sedation can be avoided and the nuclear medicine procedure can be successfully achieved simply by taking the emotional life of the child into account. Factors such as past negative experiences (painful procedures, hospitalizations), unfamiliar environment (frightening examination room), physical aggressions related to the nuclear medicine procedure (intravenous injections, cystography), and the feeling of loss of parents' protection all contribute to the child's anxiety. People in charge of pediatric procedures should be adequately trained to be aware of these factors and to create the best environmental conditions to avoid unnecessarily frightening the child. Methods for measuring renal clearance in children are numerous. It is my aim to review the different methods proposed in the literature, including the nonradioisotopic methods, the reference radioisotopic methods, the various simplified algorithms using blood samples, and the gamma-camera methods. Gastroesophageal reflux scintigraphy is a well-established procedure for the detection of gastro-esophageal reflux in children. However, despite the numerous advantages of this technique, it has not gained wide acceptance in the field of pediatric gastroenterology. This review focuses mainly on the comparison between scintigraphy and pH metry. Finally, the applications of 99m technetium-hexamethylpropylenamine brain single photon emission computer tomography in the field of pediatric neurology are still under development; this part of the review is an attempt to summarize the real contribution of this technique.

New associations of primary ciliary dyskinesia syndrome

Ten of 32 patients with primary ciliary dyskinesia syndrome (PCDS) also had other conditions. Five esophageal problems, 4 congenital heart disease, 2 scoliosis, and 4 miscellaneous and probably coincidental conditions were discovered. Additionally, a patient in this series, who has a normal heart, had a brother who died after surgery for complex congenital heart disease. In retrospect, he too probably had PCDS. The association of severe esophageal and cardiac disease with primary ciliary dyskinesia has not been described before. The diagnosis of PCDS may carry more implications than previously recognized.

Gastroesophageal reflux and sudden infant death syndrome

The possible role of gastroesophageal reflux in the pathogenesis of the sudden infant death syndrome (SIDS) has not yet been clearly defined, although it does appear that infants with significant reflux are at greater risk of respiratory complications. A study was undertaken to characterize more precisely the histological features of esophageal mucosa taken from a series of infants who died of SIDS to determine the range of changes present. Full-length strips of mucosa were examined microscopically for reflux-related changes of basal layer hyperplasia, papillary elongation, and intraepithelial eosinophilia. Eight infants (21%) showed changes considered diagnostic of reflux esophagitis, 17 infants (45%) showed minor nondiagnostic changes, and 13 infants (34%) showed no histologic abnormalities. These findings demonstrate considerable morphological heterogeneity in a group of infants presenting with sudden and unexpected death. The absence of, or presence of only very minor, pathological alterations within the esophageal mucosae of 79% of infants suggests that reflux of a degree sufficient to cause diagnostic histologic changes is found in only a minority of infants presenting with SIDS.