Gastro-oesophageal reflux and chronic respiratory disease in infants and children: treatment with cisapride

Surgery for reflux induced airway disease: a systematic review

OBJECTIVES

1. Evaluate the current evidence regarding the efficacy and safety of anti-reflux surgery for the treatment of severe gastroesophageal reflux-related airway disease in children. 2. Provide evidence based recommendations regarding indications and outcomes of anti-reflux surgery for airway disease in children.

METHODS

An a priori protocol was defined to identify all articles addressing anti-reflux surgery for the treatment of reflux-related airway disease in children where details regarding the diagnosis, treatment, and outcomes were clearly presented. The search was inclusive of all references available through August 30, 2013 and included electronic databases to identify candidate articles as well as a comprehensive series of crosschecks. The two authors independently determined which references met inclusion criteria, extracted data, and assigned levels of evidence. Data were pooled using a random effects model due to significant study heterogeneity.

RESULTS

Fourteen articles met inclusion criteria. The overall level of evidence was grade C. There was significant heterogeneity among the studies (I(2)=82.7%; p<0.001). However, each article uniformly presented cases suggesting that anti-reflux surgery is efficacious and safe in treating children with severe reflux-related respiratory disease. The pooled success rate for complete or partial resolution of symptoms after anti-reflux surgery was 0.91 (95% CI: 0.88, 0.94). The pooled success rate for complete symptom resolution after surgery was 0.72 (95% CI: 0.62, 0.83).

CONCLUSION

The current literature suggests that anti-reflux surgery is an effective and safe treatment for severe reflux-related airway disease. However, the level of evidence lacks strength and further investigation is warranted.

Omeprazole for gastroesophageal reflux disease in the first 2 years of life: a dose-finding study with dual-channel pH monitoring

BACKGROUND AND AIM

Gastroesophageal reflux occurs in the majority of infants, with severity ranging from asymptomatic to severe esophagitis and failure to thrive. Omeprazole is recognized as a safe and effective treatment of gastroesophageal reflux in older children, at an initial dosage of 0.7 mg x kg(-1) x day(-1). To our knowledge, no dose-finding studies have been carried out in children under 2 years of age. The aim of the present study was to prospectively determine the dosage of omeprazole required to treat symptomatic gastroesophageal reflux in children younger than 2 years.

PATIENTS AND METHODS

Children under 2 years with clinical suspicion of gastroesophageal reflux underwent 24-hour dual-channel intraesophageal/gastric pH monitoring. A reflux index above 10% in children under 1 year and above 6% in children older than 1 year was deemed significant. Treatment with omeprazole at an initial dosage of 0.7 mg x kg(-1) x day(-1) (in 2 divided doses) was followed by dual-channel pH study after 14 days. The dosage was increased in increments of 0.7 mg x kg(-1) x day(-1), and pH studies were repeated until the gastroesophageal reflux was controlled.

RESULTS

Ten children (5 male, 5 female), mean age 7.75 months (range, 1.25-20 months), were investigated. The initial median reflux index was 18.5% (range, 6.5%-56.3%). Follow-up median reflux index was improved at 1.6% (0.1%-8.1%) (P < 0.05). The median dosage required was 1.05 mg x kg(-1) x day(-1). Four children required 1.4 mg x kg(-1) x day(-1), and 1 required 2.8 mg x kg(-1) x day(-1). Corrected reflux index improved from 34.8% (16.8%-90.8%) to 20.1% (0.4%-100%) but did not achieve statistical significance. There were no serious complications or side effects.

CONCLUSIONS

Omeprazole is an effective treatment for gastroesophageal reflux in children younger than 2 years. The majority respond to a dosage of 0.7 mg x kg(-1) x day(-1), but increased dosages up to 2.8 mg x kg(-1) x day(-1) may be required.

Supra-oesophageal manifestations of gastro-oesophageal reflux disease

Since the early 1960s, many studies have been published that consider the possible relationship between gastro-oesophageal (acid) reflux (GORD) and various other complaints, including dental erosions, ear, nose and throat problems, chronic cough and asthma. Although a high coincidence of GORD and these supra-oesophageal complaints have been noted, there is no consensus on the pathophysiology and management of such complications. In this article we review the literature published between 1966 and 2000 on this subject. We also analyse the available information on the incidence, pathophysiological mechanisms, diagnostic approach and therapeutic options in the various subgroups of disorders.

Esophageal biopsy for the diagnosis of gastroesophageal reflux-associated otolaryngologic problems in children

Recently, gastroesophageal reflux (GER) has been found to contribute to many types of otolaryngologic pathology in infants and children. The complaints may be intermittent and unresponsive to usual therapies, such as antimicrobial treatments. A high index of suspicion for GER and for the concept of "silent" GER (GER without overt symptoms) is necessary for accurate diagnosis and treatment of otolaryngologic manifestations of GER in these patients. In this prospective historical cohort study, the records were reviewed from 101 children who underwent esophagoscopy and biopsy as a diagnostic test for GER at the time of other otolaryngologic procedures. Significant associations were found between the presence of histologic esophagitis and asthma, recurrent croup, cough, apnea, sinusitis, stridor, laryngomalacia, subglottic stenosis, posterior glottic erythema, and posterior glottic edema. There were no complications. Esophageal biopsy is a rapid, safe and effective diagnostic test for GER that should be considered at the time of other procedures in children with selected GER-associated problems.

Chronic prenatal exposure to carbon monoxide results in a reduction in tyrosine hydroxylase-immunoreactivity and an increase in choline acetyltransferase-immunoreactivity in the fetal medulla: implications for Sudden Infant Death Syndrome

Maternal cigarette smoking during pregnancy is associated with a significantly increased risk of Sudden Infant Death Syndrome (SIDS). This study investigated the effects of prenatal exposure to carbon monoxide (CO), a major component of cigarette smoke, on the neuroglial and neurochemical development of the medulla in the fetal guinea pig. Pregnant guinea pigs were exposed to 200 p.p.m CO for 10 h per day from day 23-25 of gestation (term = 68 days) until day 61-63, at which time fetuses were removed and brains collected for analysis. Using immunohistochemistry and quantitative image analysis, examination of the medulla of CO-exposed fetuses revealed a significant decrease in tyrosine hydroxylase-immunoreactivity (TH-IR) in the nucleus tractus solitarius, dorsal motor nucleus of the vagus (DMV), area postrema, intermediate reticular nucleus, and the ventrolateral medulla (VLM), and a significant increase in choline acetyltransferase-immunoreactivity (ChAT-IR) in the DMV and hypoglossal nucleus compared with controls. There was no difference between groups in immunoreactivity for the m2 muscarinic acetylcholine receptor, substance P- or met-enkephalin in any of the medullary nuclei examined, nor was there evidence of reactive astrogliosis. The results show that prenatal exposure to CO affects cholinergic and catecholaminergic pathways in the medulla of the guinea pig fetus, particularly in cardiorespiratory centers, regions thought to be compromised in SIDS.

Population pharmacokinetics of enterally administered cisapride in young infants with gastro-oesophageal reflux disease

AIMS

To investigate the pharmacokinetics of enterally administered cisapride suspension in young infants being treated for gastro-oesophageal reflux disease.

METHODS

Plasma cisapride concentrations in 49 subjects (weight: 825-5010 g; n=108 samples, median two per patient; concentration: 14.8-170 ng ml-1 ) were fitted to a one-compartment model with first-order absorption and elimination in the NONMEM program using a logarithmic transformation of the observed and predicted concentrations. Fitting was achieved using the first order conditional estimation (FOCE) method with interaction between the interpatient and intrapatient variabilities. The interpatient variance of clearance (CL/F ) and volume of distribution (V /F ) and their covariance were estimated using an exponential error model. Intrapatient (residual) variance was estimated using an additive model.

RESULTS

The clearance of cisapride was shown to be linearly related to current body weight, slope: 0.538. The typical population values of CL/F, V /F and Ka (absorption rate constant) were 0.538 l h-1 kg-1, 21.9 l, and 2.58 h-1, respectively. The population coefficients of variation (CV%) for CL/F and V/F were 34.4% and 84.3%, respectively. The squared coefficient of correlation between random effects for CL/F and V /F was 0.45. The intrapatient variance was 0.15. V /F and Ka were not influenced significantly by any patient characteristic.

CONCLUSIONS

Cisapride pharmacokinetics in infants with reflux disease were satisfactorily described by a one-compartment model. Current weight should be taken into account when calculating maintenance cisapride doses in these infants.

Gastroesophageal reflux and asthma: a review of pathogenesis, diagnosis, and therapy

Gastroesophageal reflux disease (GERD) occurs in up to one-third of the adult US population. Most affected individuals are either unaware of their condition or do not seek medical help, relying on nonprescription acid suppressants and antacids for relief. GERD, a common disorder of infancy, old age, and pregnancy, is particularly prevalent in patients with asthma. A causal relationship between the two diseases has been postulated by many investigators. The physiologic changes of asthma exacerbations and the actions of some of the medications used to treat asthma both aggravate GERD. The adverse effect of GERD on asthma and the pathophysiology of this relationship are still under debate. Some studies showed no objective improvement by spirometry of asthmatics treated for GERD, but recognized improvement in asthma symptoms and decreased use of asthma medication. Other studies, supporting GERD induction of asthma, have been performed to test two hypotheses: that asthma is exacerbated by endotracheal aspiration of gastric contents or by a reflex response to stimulation of esophageal receptors. Clinical experience has shown that early diagnosis and treatment of GERD often leads to better control of asthma.

Dyspepsia in infants and children

Pathological processes and diseases of the upper gastrointestinal tract have become increasingly recognized over recent years as childhood entities responsible for a variety of upper gastrointestinal symptoms previously labelled as functional or non-organic. The term 'dyspepsia' is an adult one whose definition requires clarification before use in the paediatric context, but it encompasses age-dependent symptoms such as feed-associated irritability in the infant, peri-umbilical pain in the younger child, and heart-burn, nausea, and indigestion in the older child as in adults. The possible organic conditions giving rise to such symptoms are multiple and multiorgan and include: gastro-oesophageal reflux; peptic ulcer disease; upper gastrointestinal Crohn's disease; antroduodenal motility disorders; pancreatitis; cholecystitis; cholelithiasis; biliary dyskinesia; and abdominal migraine. However, Munchausen syndrome by proxy must not be forgotten. Non-ulcer dyspepsia, it is now clear, has a basis in altered gastroduodenal motility and may be amenable to propulsion agents. In many individuals the dyspeptic symptoms of recurrent abdominal pain may be altered by psychotherapeutic intervention. Indeed there remains a proportion of children who undoubtedly have a behavioural or psychological base to their complaint. Nevertheless, with the recent increase in diagnostic yield from improved technical investigative aids available to paediatrics in the last 5-10 years, it is clear that the responsibility of the paediatrician to the child to find a cause of their symptoms is paramount. The variety of presenting features, possible causes of these symptoms, and appropriate investigation and treatment will be discussed, and management algorithms based on published literature and personal practice will be offered.

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.