Esophageal motor abnormalities in children and adolescents with scleroderma and mixed connective tissue disease.

To determine the frequency and nature of esophageal motor abnormalities in children and adolescents with scleroderma syndromes and mixed connective tissue disease, esophageal manometry was performed on seven patients with progressive systemic sclerosis, four patients with mixed connective tissue disease, and two patients with linear scleroderma. A total of 73% of patients with progressive systemic sclerosis and mixed connective tissue disease had symptoms of esophageal dysfunction. A significant association between the presence of Raynaud phenomenon and esophageal symptoms was noted. Esophageal motor abnormalities were detected in 73% of patients with progressive systemic sclerosis and mixed connective tissue disease; these abnormalities were characterized by decreased lower esophageal sphincter pressure and abnormal peristalsis in the distal two thirds of the esophageal body. They resemble those described among adults with progressive systemic sclerosis and mixed connective tissue disease but were not related to disease duration or to the presence of Raynaud phenomenon. Patients with linear scleroderma did not have esophageal symptoms and demonstrated only nonspecific motor abnormalities that did not worsen during several years of follow-up.

Mechanisms for the association of gastroesophageal reflux and bronchospasm.

The mechanism for the association between gastroesophageal reflux and bronchospasm is probably multifactorial. Our data support the view that microaspiration into the trachea may be an important mechanism for bronchospasm induced by gastroesophageal reflux and needs to be distinguished from simple reflux into the esophagus. Intraesophageal acidification alone quantitatively produces a much smaller airway response than does intratracheal acidification. A challenge test should be developed to correlate airway response following intraesophageal acidification to airway hyperactivity. We believe that the relationship of the diaphragm to the antireflux barrier deserves further study.

Role of the diaphragm in the genesis of lower esophageal sphincter pressure in the cat.

To determine the role of the diaphragm in the genesis of the high-pressure zone at the lower esophageal sphincter (LES) we studied the effect of diaphragmatic contraction on lower esophageal sphincter pressure in 10 anesthetized adult cats. Despite anchoring the pressure recording assembly within the LES to prevent axial movement of the sphincter during respiration relative to the pressure recording ports, there was an average oscillation in LES pressure of 17.4 +/- 5.5 mmHg, the frequency of which was the same as the respiratory rate. Peak LES pressure occurred at end-inspiration corresponding with peak diaphragmatic electromyogram. During periods of central apnea induced by manual hyperventilation there was absence of both diaphragmatic electromyogram and the oscillations in LES pressure. Lower esophageal sphincter pressure during apnea was equal to end-expiratory pressure during spontaneous respiration. Following complete neuromuscular blockade with pancuronium, artificial respiration with increasing tidal volumes resulted in increasing oscillations in pressure. However, the magnitude of the pressure oscillation even at tidal volumes four times normal was always significantly below that observed during spontaneous eupnic respiration. Furthermore, progressive augmentation of diaphragmatic electromyogram activity by breathing 5% CO2 in air revealed a linear correlation between the magnitude of the respiratory-induced pressure oscillations of the LES and peak integrated diaphragmatic electromyogram in individual animals. It is concluded, therefore, that (a) intrinsic LES tone is best approximated by end-expiratory pressure during spontaneous respiration, (b) the respiratory-induced oscillations in LES pressure are primarily the result of active diaphragmatic contraction, and (c) the level of diaphragmatic electrical activity directly influences the magnitude of the pressure oscillation.

Comparison of airway responses following tracheal or esophageal acidification in the cat.

To determine a possible mechanism for the association between gastroesophageal reflux and obstructive pulmonary disease, we quantitatively compared the short latent airway response after acid infusion into the trachea or esophagus in 13 anesthetized adult cats. Total lung resistance was calculated from synchronous measurements of air flow and intrapleural pressure differences from those at end expiratory level. Tracheal infusion of as little as 0.05 ml of 0.2 N HCl evoked an average 4.65-fold increase in total lung resistance from baseline in all animals tested (p less than 0.005). Intratracheal saline had no effect. The response to intratracheal acid infusion was rapidly adapting, pH dependent, and vagally mediated. Infusion of a much larger volume of 10 ml of 0.2 N HCl into the esophagus produced an average 1.47-fold increase in total lung resistance from baseline (p less than 0.05). No change was seen with intraesophageal saline. In contrast to intratracheal acid infusion, a clearly significant increase in resistance was seen in only 8 of 13 animals tested after intraesophageal acidification. When it occurred, the response was sustained for at least 60 s after acid infusion. The magnitude of the response was not augmented by the presence of severe esophagitis. These studies strengthen the concept that reflex pathways in the trachea and esophagus may explain a causal relationship between gastroesophageal reflux and obstructive pulmonary diseases. The results support the view that microaspiration into the trachea is a much more likely mechanism for bronchospasm associated with gastroesophageal reflux than simple acid reflux into the esophagus.

Awake apnea associated with gastroesophageal reflux: a specific clinical syndrome.

Fifteen infants with a specific clinical history including awake apnea were evaluated and compared with a control group of infants, using 24-hour studies of esophageal pH, nasal thermistor, impedance pneumography, and heart rate. Thirteen of the 15 children with awake apnea had clearly documented episodes of airway obstruction in associated with gastroesophageal reflux occurring at least twice during the study (mean 3.9 +/- 0.7, range 2 to 9). The control group did not show similar findings. All 15 children with awake apnea had frequent episodes of gastroesophageal reflux. Treatment with home monitoring and reflux precautions was successful in 10 of 15. Five children received therapy with urecholine hydrochloride because of continuing episodes of reflux-associated apnea. Two children subsequently required Nissen fundoplication, primarily for symptoms of severe esophagitis. Our data suggest that in children with awake apnea, the apnea is associated with gastroesophageal reflux. Medical management is usually successful, but fundoplication may be needed in refractory cases.

Mucocutaneous lymph node syndrome with hydrops of the gallbladder diagnosed by ultrasound.

One of the complications of the mucocutaneous lymph node syndrome is acute hydrops of the gallbladder. Although surgery may be required occasionally, spontaneous resolution of gallbladder hydrops in patients is common. Ultrasound is the optimal method for evaluating these patients.