How useful is gastroesophageal reflux scintigraphy in suspected childhood aspiration?

Scintigraphic Evaluation of Gastroesophageal Reflux and Pulmonary Aspiration in Children

Gastroesophageal reflux (GER) and pulmonary aspiration are encountered in children of all ages. Signs, symptoms, and complications vary from mild and transient to severe life-threatening conditions. This review will present relevant clinical information on these conditions as well as common diagnostic procedures. The role of scintigraphic techniques used in the evaluation of these conditions will be discussed in detail including protocols and performance in comparison to other diagnostic methods.

Utility of salivagram in pulmonary aspiration in pediatric patients: comparison of salivagram and chest radiography

OBJECTIVE

The purpose of our study was to correlate the results of the radionuclide salivagram with the corresponding chest radiography findings on patients being evaluated for salivary aspiration to determine the utility of the salivagram.

MATERIALS AND METHODS

We identified 222 patients younger than 21 years who underwent salivagram and chest radiography within 3 months of each other. Salivagrams were blindly interpreted by two readers and chest radiographs were blindly interpreted by two other readers. The kappa coefficient with 95% CI was used to measure the level of interobserver agreement. Multivariate logistic regression was applied to determine whether age, sex, and neurologic diagnosis were predictors of a positive salivagram, with the odds ratio used to estimate association.

RESULTS

Interobserver agreement on salivagram interpretation was excellent (κ = 0.988; p < 0.0001; 95% CI, 0.968-1.000). Interobserver agreement on chest radiography interpretation was excellent (κ = 0.905; p < 0.0001; 95% CI, 0.845-0.965). The salivagram was positive for aspiration in 55 patients (25%). Chest radiography was positive in 54 patients (24%). When the interpretations of the salivagram (normal or abnormal) were compared with interpretations of the chest radiograph (normal or abnormal), there were 213 agreements and nine disagreements (intermethod agreement κ = 0.891; p < 0.0001; 95% CI, 0.831-0.952). Independent of age (p = 0.80) and sex (p = 0.31), patients with a neurologic diagnosis had odds of a positive salivagram 5.6 times higher than other diagnoses (odds ratio = 5.6; 95% CI, 2.5-13.1; p < 0.0001).

CONCLUSION

Infants with abnormal findings on salivagrams also had a high rate of abnormal findings on chest radiographs, which may indicate that some of the lung disease may be due to aspirated saliva. Salivagrams may be useful in children at risk of aspiration to identify those in whom intervention may help minimize the consequences of aspiration.

Pepsin measured in induced sputum--a test for pulmonary aspiration in children?

PURPOSE

The purpose of this study was to investigate if pepsin measured in sputum is a useful marker of pulmonary aspiration secondary to gastroesophageal reflux (GER) in children. It is possible that the induced sputum procedure could cause GER and invalidate the results. The hypothesis stated that healthy children (those without history of respiratory or gastroesophageal symptoms) would not have pepsin detected in induced sputum.

METHODS

Children attending surgical outpatients in the Royal Belfast Hospital for Sick Children (Belfast, Northern Ireland) were recruited. After spirometry, sputum was obtained by induction with hypertonic 3% saline. Spirometry was repeated, and complications were noted. An "in-house" enzyme-linked immunosorbent assay was used to measure pepsin concentration in sputum. The lower limit of detection of pepsin was 1.19 ng/mL.

RESULTS

Children (n = 21) aged 4 to 16 years were recruited. Twenty children completed the study. No adverse effects were reported. Pepsin was detected in 17 (85%) of 20 sputum samples.

CONCLUSIONS

The act of sputum induction appears to induce physiologic GER in a healthy childhood population. The analysis of pepsin in sputum obtained by sputum induction is therefore not useful in the investigation of reflux-related respiratory disease.

Pediatric gastroesophageal reflux clinical practice guidelines: joint recommendations of the North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition (NASPGHAN) and the European Society for Pediatric Gastroenterology, Hepatology, and Nutrition (ESPGHAN)

OBJECTIVE

To develop a North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition (NASPGHAN) and European Society for Pediatric Gastroenterology, Hepatology, and Nutrition (ESPGHAN) international consensus on the diagnosis and management of gastroesophageal reflux and gastroesophageal reflux disease in the pediatric population.

METHODS

An international panel of 9 pediatric gastroenterologists and 2 epidemiologists were selected by both societies, which developed these guidelines based on the Delphi principle. Statements were based on systematic literature searches using the best-available evidence from PubMed, Cumulative Index to Nursing and Allied Health Literature, and bibliographies. The committee convened in face-to-face meetings 3 times. Consensus was achieved for all recommendations through nominal group technique, a structured, quantitative method. Articles were evaluated using the Oxford Centre for Evidence-based Medicine Levels of Evidence. Using the Oxford Grades of Recommendation, the quality of evidence of each of the recommendations made by the committee was determined and is summarized in appendices.

RESULTS

More than 600 articles were reviewed for this work. The document provides evidence-based guidelines for the diagnosis and management of gastroesophageal reflux and gastroesophageal reflux disease in the pediatric population.

CONCLUSIONS

This document is intended to be used in daily practice for the development of future clinical practice guidelines and as a basis for clinical trials.

Systematic review: the extra-oesophageal symptoms of gastro-oesophageal reflux disease in children

BACKGROUND

Extra-oesophageal symptoms are thought to be common, atypical symptoms of gastro-oesophageal reflux disease (GERD) in children.

AIM

To investigate the prevalence of GERD in children with extra-oesophageal symptoms or of extra-oesophageal symptoms in children with GERD, and the effect of GERD therapies on extra-oesophageal symptoms.

METHODS

A systematic review of articles in PubMed and EMBASE.

RESULTS

We identified 18 relevant articles. The pooled weighted average prevalence of GERD in asthmatic children was 23%, compared with 4% in healthy controls from the same five studies. The majority of studies evaluating the relationship between apparent life-threatening event (ALTE) and GERD did not suggest a causal relationship. Seven studies reported that respiratory symptoms, sinusitis and dental erosion were significantly more prevalent in children with GERD than in controls. Data from pharmacotherapeutic trials were inconclusive and provided no support for a causal relationship between GERD and extra-oesophageal symptoms.

CONCLUSIONS

Possible associations exist between GERD and asthma, pneumonia, bronchiectasis, ALTE, laryngotracheitis, sinusitis and dental erosion, but causality or temporal association were not established. Moreover, the paucity of studies, small sample sizes and varying disease definitions did not allow firm conclusions to be drawn. Most trials of GERD therapies showed no improvement in extra-oesophageal symptoms in children.

Aspiration lung disease

The term aspiration lung disease describes several clinical syndromes, with massive aspiration and chronic lung aspiration being at two extremes of the clinical spectrum. Over the years, significant advances have been made in understanding the mechanisms underlying dysphagia, gastroesophageal function, and airway protective reflexes and new diagnostic techniques have been introduced. Despite this, characterizing the presence or absence of aspiration, and under what circumstances a child might be aspirating what, is extremely challenging. Many children are still not adequately diagnosed or treated for aspiration until permanent lung damage has occurred. A multidisciplinary approach is mandatory for a correct diagnosis in addition to timely and appropriate care.

Assessment of the prevalence of microaspiration by gastric pepsin in the airway of ventilated children

AIM

Mechanically ventilated patients are at risk for aspiration of gastric contents. The aim of this observational study was to determine the prevalence of micro-aspiration in children with cuffed and uncuffed endotracheal (ET) tubes and with tracheostomies and to assess the effect of feeding status on aspiration. Micro-aspiration was determined by measuring gastric pepsin in tracheal aspirates.

METHODS

We studied 27 children on ventilators in paediatric intensive care unit (PICU) and 10 children undergoing elective surgeries for various indications. Tracheal aspirates were collected from children on ventilatory support in the intensive care unit during medically indicated suctioning and from the group of children undergoing elective surgery in the operation room. Pepsin was detected by enzymatic assay.

RESULTS

Overall 70% of cases in PICU were positive for pepsin in at least one of the aspirates. Pepsin positivity was significantly lower in the cuffed group than in the uncuffed and tracheostomy groups. Tube feedings did not significantly influence the prevalence of pepsin positivity.

CONCLUSIONS

Measurement of gastric pepsin in tracheobronchial fluid is a sensitive tool to detect aspirations in mechanically ventilated children and to assess the efficacy of preventive measures in PICU settings.

Pulmonary aspiration shown by scintigraphy in gastroesophageal reflux-related respiratory disease

OBJECTIVES

Gastroesophageal reflux (GER) may underlie respiratory manifestations via vagally mediated airway hyperresponsiveness or microaspiration, and intraesophageal pH monitoring is generally used to identify GER in patients with such manifestations. We aimed to establish the frequency of retrograde pulmonary aspiration in patients with unexplained respiratory manifestations.

METHODS

Fifty-one patients with refractory respiratory symptoms (cough, n = 18; pneumonia, n = 14; apnea, n = 8; asthma, n = 7; and laryngitis, n = 4) were prospectively evaluated. They underwent 24-h intraesophageal pH monitoring and gastroesophageal 99Tc scintigraphy with lung scan 18 to 20 h after the test meal.

RESULTS

Thirteen of 51 patients (25.5%) had abnormal intraesophageal pH study results (mean reflux index, 11.3%; range, 6.5 to 50%); and in 25 of 51 patients (49%), overnight scintigraphy showed pulmonary aspiration. Nineteen of these 25 patients had entirely normal pH study results, whereas 6 of 13 patients with abnormal pH study results had aspiration. Pulmonary aspiration was demonstrated in all patients with apnea and 61.5% of patients with recurrent pneumonia. Nine of 25 patients (36%) with aspiration had histologic evidence of esophagitis, whereas histologic esophagitis was present in 5 of 13 patients (38.4%) with pathologic GER as shown by intraesophageal pH monitoring.

CONCLUSIONS

Pulmonary aspiration as demonstrated by overnight scintigraphy is common in children with unexplained and refractory respiratory manifestations, suggesting that GER could be the underlying cause of these manifestations. Since only a few children with chronic or recurrent respiratory symptoms have a pathologic gastroesophageal acid reflux, a normal intraesophageal pH study result does not rule out GER in these children.

Investigation and management of dysphagia

Dysphagia is a common finding in infants and children with neuromuscular disabilities. Dysphagia may be developmental, as in the preterm infant, transient, chronic, or progressive. The evaluation of dysphagia must take into account the age of the patient and typical development of feeding and swallowing for that age. The typical abilities seen in neonatal, early infancy, later infancy and early childhood periods vary in sensorimotor skills and feeding efficiency. In addition to knowing the substrate of expected skills by age, knowledge of the neurophysiology of feeding and swallowing is essential to diagnosis. Each physiologic phase of deglutition: oral, pharyngeal, and esophageal can present with symptoms of dysphagia that can guide investigation. Common symptoms of dysphagia include generalized feeding difficulty such as poor efficiency, food refusal and failure to thrive. Specific symptoms include tongue thrust, choking, cough, and oxygen desaturation. The possibility of dysphagia can be identified through a thorough feeding history. Examination initially includes the infant's muscle tone and posture in the head, neck and body. Anomalies of structures of the head and neck must be identified and examined for their effect on function. Next, examination of oral structures for reflexes, tongue movements, and symmetry will identify neurologic abnormalities. Observation of feeding is essential and will reveal signs of dysphagia. Aspiration in the infant can present without specific signs. Respiratory abnormalities or Gastroesophageal reflux can be identified during history or examination. Investigation of dysphagia most commonly includes videofluoroscopy, endoscopy, and ultrasonography. The management of dysphagia requires an individualized approach and will include neurologic, respiratory, nutritional and possibly gastrointestinal management. Six broad areas are identified that must be considered in the management of dysphagia in infants and children. They include: normalization of posture and positioning, adaptation of foods and feeding equipment, oromotor therapy, feeding therapy, nutritional support and management of associated disorders. A team of professionals will assist the parent and child in achieving pleasant feedings to foster appropriate growth and development.

Assay of tracheal pepsin as a marker of reflux aspiration

OBJECTIVES

Aspiration of gastric contents is a relatively common cause of acute and chronic pulmonary disease. However, a reliable method of diagnosing recurrent aspiration is currently lacking. The aim of this study was to determine whether the presence of gastric pepsin in tracheal aspirates of infants and children might be used as a reliable marker of the microaspiration of refluxed gastric contents.

METHODS

Ninety-eight children undergoing general anesthesia and tracheal intubation participated in the study. Sixty-four of 98 children underwent endoscopy for clinically significant gastroesophageal reflux. Thirty-four children from routine operative lists were nonreflux controls. These two groups were further subdivided based on the presence or absence of associated respiratory symptoms. After endotracheal intubation, tracheal aspirates were obtained and subsequently assayed for gastric pepsin using a fluoroscein isothiocyanate casein.

RESULTS

Pepsin was detected in 7 of 27 children with reflux symptoms alone and in 7 of 8 of those with chronic respiratory symptoms. In addition, pepsin was present in 31 of 37 children with a history of both reflux and chronic respiratory symptoms. Tracheal pepsin was not detected in any of the 26 children without gastroesophageal reflux or respiratory symptoms. Tracheal pepsin was found significantly more frequently in children with reflux symptoms than in those without, particularly in children with both reflux and respiratory problems.

CONCLUSION

Tracheal pepsin assay as a reliable marker of gastroesophageal reflux aspiration.

Fat laden macrophages in tracheal aspirates as a marker of reflux aspiration: a negative report

OBJECTIVES

Refluxed gastric material aspirated into the lungs is an important cause of acute and chronic pulmonary disease. Currently, the presence of fat-laden macrophages (FLM) in tracheobronchial secretions of children is a conventional marker for reflux aspiration. However, this assay is limited by its apparent lack of specificity. The aim of this study was to reevaluate the role of this assay in diagnosing reflux aspiration.

METHODS

The tracheal aspirates of sixty-four consecutive children with clinically significant gastroesophageal reflux undergoing upper gastrointestinal endoscopy under general anesthesia, and 34 other children from the routine operative schedule were evaluated. Both groups were further subdivided on the basis of presence or absence of associated respiratory symptoms. After intubation, tracheal aspirates were collected, fixed, and stained for FLM. By grading the amount of intracellular fat present, a semiquantitative lipid index was computed. Tracheal aspirates with a lipid index of 100 or greater were considered positive.

RESULTS

Twenty-four of the 64 children with reflux symptoms and 14 of 34 children without reflux symptoms were positive for FLM. Sixteen of 37 children with both gastroesophageal reflux and respiratory symptoms and 10 of 26 children negative for both tested positive for FLM. The mean lipid index of the subgroup of children with both reflux and respiratory symptoms was not significantly different from that of the subgroup that was negative for both conditions. Despite computing a semiquantitative lipid index, an index of 100 or greater only had a sensitivity of 38% and specificity of 59%.

CONCLUSION

Assay of FLM in the tracheal aspirates of children considered at risk of reflux aspiration is not a sensitive or specific as a marker for reflux aspiration.

Guidelines for evaluation and treatment of gastroesophageal reflux in infants and children: recommendations of the North American Society for Pediatric Gastroenterology and Nutrition

Gastroesophageal reflux (GER), defined as passage of gastric contents into the esophagus, and GER disease (GERD), defined as symptoms or complications of GER, are common pediatric problems encountered by both primary and specialty medical providers. Clinical manifestations of GERD in children include vomiting, poor weight gain, dysphagia, abdominal or substernal pain, esophagitis and respiratory disorders. The GER Guideline Committee of the North American Society for Pediatric Gastroenterology and Nutrition has formulated a clinical practice guideline for the management of pediatric GER. The GER Guideline Committee, consisting of a primary care pediatrician, two clinical epidemiologists (who also practice primary care pediatrics) and five pediatric gastroenterologists, based its recommendations on an integration of a comprehensive and systematic review of the medical literature combined with expert opinion. Consensus was achieved through Nominal Group Technique, a structured quantitative method. The Committee examined the value of diagnostic tests and treatment modalities commonly used for the management of GERD, and how those interventions can be applied to clinical situations in the infant and older child. The guideline provides recommendations for management by the primary care provider, including evaluation, initial treatment, follow-up management and indications for consultation by a specialist. The guideline also provides recommendations for management by the pediatric gastroenterologist. This document represents the official recommendations of the North American Society for Pediatric Gastroenterology and Nutrition on the evaluation and treatment of gastroesophageal reflux in infants and children. The American Academy of Pediatrics has also endorsed these recommendations. The recommendations are summarized in a synopsis within the article. This review and recommendations are a general guideline and are not intended as a substitute for clinical judgment or as a protocol for the management of all patients with this problem.

Gastroesophageal reflux disease in asthma: effects of medical and surgical antireflux therapy on asthma control

OBJECTIVE

To critique the English-language reports describing the effects of medical and surgical antireflux therapy on respiratory symptoms and function in patients with asthma.

METHODS

The Medline computerized database (1959-1999) was searched, and all publications relating to both asthma and gastroesophageal reflux disease were retrieved.

RESULTS

Seven of nine trials of histamine-receptor antagonists showed a treatment-related improvement in asthma symptoms, with half of the patients benefiting. Only one study identified a beneficial effect on objective measures of pulmonary function. Three of six trials of proton pump inhibitors documented improvement in asthma symptoms with treatment; benefit was seen in 25% of patients. Half of the studies reported improvement in pulmonary function, but the effect occurred in fewer than 15% of patients. In the one study that used optimal antisecretory therapy, asthma symptoms were improved in 67% of patients and pulmonary function was improved in 20%. Combined data from 5 pediatric and 14 adult studies of anti-reflux surgery indicated that almost 90% of children and 70% of adults had improvement in respiratory symptoms, with approximately one third experiencing improvements in objective measures of pulmonary function.

CONCLUSIONS

Fundoplication has been consistently shown to ameliorate reflux-induced asthma; results are superior to the published results of antisecretory therapy. Optimal medical therapy may offer similar results, but large studies providing support for this assertion are lacking.

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.

Scintigraphic evaluation of esophageal transit and gastric emptying in familial dysautonomia

Gastroesophageal dysfunction is a major cause of morbidity and mortality in patients with familial dysautonomia (FD). Most studies evaluating esophageal and gastric function in FD patients are either insensitive or invasive. Thus we have used a "milk" scan to quantitate abnormalities in esophageal transit and gastric emptying, while searching for gastroesophageal reflux and aspiration in these patients. The quantitative scintigraphic evaluation was performed in 35 patients with FD, 10 of whom were studied after fundoplication, pyloroplasty and gastrostomy. A prolonged esophageal transit time, ranging from 8 s to more than 60 s duration, was demonstrated in 11 patients. Gastroesophageal reflux was detected in 26 patients. In 16 patients delayed gastric emptying ranging from 63-94% was detected at 30 min, and in 13 patients delayed emptying ranging from 37-86% was observed at 120 min. Pulmonary aspiration was detected in 8 non-operated patients, four of whom had abnormal gastric emptying. The scintigraphic analysis of both esophageal transit and gastric emptying in familial dysautonomia is presented, and its role in evaluation and management of these patients discussed.

Scintigraphic detection of gastro-pulmonary aspiration in patients with respiratory disorders

The scintigraphic detection of small nocturnal aspirations of radio-labelled gastric contents is difficult in the presence of high remaining activity in the abdomen, causing a non-uniform background activity. This problem was examined in phantom experiments and a technique for interpolative background correction was further developed. The accuracy of this technique was found to be influenced by the distance between the lung and the abdominal source of activity, and the minimum detectable 'aspirated' activity was determined as 0.1 MBq at a distance of 15 cm and 1 MBq at 5 cm. The interpolative technique for background correction was evaluated on healthy volunteers and laryngectomized patients, examined 10 h after intragastric instillation of 200 MBq of 99Tcm-pertechnetate. After background subtraction, their calculated pulmonary mean net count value was comparable to that registered before the radioactive tracer was administered. No localized accumulation of activity was found in any of these controls. The technique was then applied clinically to 55 patients with chronic respiratory disorders and symptoms of gastroesophageal reflux. Aspiration was detected in 11 patients (20%). Five aspirators had asthma, two a chronic cough of unknown origin, two recurrent pulmonary infections, and one chronic bronchitis and chronic laryngitis respectively. Aspiration was detected among patients with and without demonstrated pathological gastroesophageal reflux.