Analysis of fasting antroduodenal manometry in children

Antroduodenal manometry has been used to determine the pathophysiology associated with signs and symptoms of gastrointestinal motility disorders. The diagnostic value of antroduodenal manomentry has been limited by the paucity of data from normal children. In this study, we compared antroduodenal manometry findings from 95 patients with symptoms suggesting a gastrointestinal motility disorder to 20 control children. Phase III of the migrating motor complex (MMC) was less frequent in patients (P<0.05), especially in those who required total parenteral nutrition (P<0.001), than in controls. Abnormal migration of phase III and short intervals between phase IIIs were more frequent in patients than in controls (P<0.01 andP<0.05, respectively). During phase II, persistent low-amplitude contractions and sustained tonic-phasic contraction were found only in parenteral-nutrition-dependent children. Short or prolonged duration of phase III, absence of phase I following phase III, tonic contractions during phase III, low amplitude of phase III contractions in a single recording site and clusters of contractions or prolonged propagating contractions during phase II were not more frequent in patients than in controls. We conclude that there are five manometric features having a clear association with pediatric gastrointestinal motility disorders: (1) absence of phase III of the MMC, (2) abnormal migration of phase III, (3) short intervals between phase III episodes, (4) persistent low-amplitude contractions, and (5) sustained tonic-phasic contractions.     

High-resolution manometry and impedance-pH/manometry: valuable tools in clinical and investigational esophagology

Both high-resolution manometry (HRM) and impedance-pH/manometry monitoring have established themselves as research tools and both are now emerging in the clinical arena. Solid-state HRM capable of simultaneously monitoring the entire pressure profile from the pharynx to the stomach along with pressure topography plotting represents an evolution in esophageal manometry. Two strengths of HRM with pressure topography plots compared with conventional manometric recordings are (1) accurately delineating and tracking the movement of functionally defined contractile elements of the esophagus and its sphincters, and (2) easily distinguishing between luminal pressurization attributable to spastic contractions and that resultant from a trapped bolus in a dysfunctional esophagus. Making these distinctions objectifies the identification of achalasia, distal esophageal spasm, functional obstruction, and subtypes thereof. Ambulatory intraluminal impedance pH monitoring has opened our eyes to the trafficking of much more than acid reflux through the esophageal lumen. It is clear that acid reflux as identified by a conventional pH electrode represents only a subset of reflux events with many more reflux episodes being composed of less acidic and gaseous mixtures. This has prompted many investigations into the genesis of refractory reflux symptoms. However, with both technologies, the challenge has been to make sense of the vastly expanded datasets. At the very least, HRM is a major technological tweak on conventional manometry, and impedance pH monitoring yields information above and beyond that gained from conventional pH monitoring studies. Ultimately, however, both technologies will be strengthened as outcome studies evaluating their utilization become available.     

Comparison of idiopathic achalasia and Chagas' disease esophagopathy at the light of high‐resolution manometry

The comparison between idiopathic achalasia (IA) and Chagas' disease esophagopathy (CDE) may evaluate if treatment options and their outcomes can be accepted universally. This study aims to compare IA and CDE at the light of high‐resolution manometry. We studied 86 patients with achalasia: 45 patients with CDE (54% females, mean age 55 years) and 41 patients with IA (58% females, mean age 49 years). All patients underwent high‐resolution manometry. Upper esophageal sphincter parameters were similar (basal pressure CDE = 72 ± 45 mmHg, IA = 82 ± 57 mmHg; residual pressure CDE = 9.9 ± 9.9 mmHg, IA = 9.8 ± 7.5 mmHg). In the body of the esophagus, the amplitude was higher in the IA group than the CDE group at 3 cm (CDE = 15 ± 14 mm Hg, IA = 42 ± 52 mmHg, P = 0.003) and 7 cm (CDE = 16 ± 15 mmHg, IA = 36 ± 57 mmHg, P = 0.04) above the lower esophageal sphincter (LES). The LES basal pressure (CDE = 17 ± 16 mmHg, IA = 40 ± 22 mmHg, P < 0.001) and residual pressure (CDE = 12 ± 11 mmHg, IA = 27 ± 13 mmHg, P < 0.001) were also higher in the IA group. Our results show that: (i) there is no difference in regards to the upper esophageal sphincter; (ii) higher pressures of the esophageal body are noticed in patients with IA; and (iii) basal and residual pressures of the LES are lower in patients with CDE. Our results did not show expressive manometric differences between IA and CDE. Some differences may be attributed to a more pronounced esophageal dilatation in patients with CDE.     

Gastroesophageal reflux disease and patterns of reflux in patients with idiopathic pulmonary fibrosis using hypopharyngeal multichannel intraluminal impedance

Idiopathic pulmonary fibrosis (IPF) is a diffuse fibrotic lung disease of unknown etiology. The association between IPF and gastroesophageal reflux disease (GERD) has been suggested. The objective of this study was to determine the prevalence of GERD and assess the proximity of reflux events in patients with histologically proven IPF using hypopharyngeal multichannel intraluminal impedance (HMII). This is a retrospective review of prospectively collected data from patients with histologically confirmed IPF (via lung biopsy) who underwent objective esophageal physiology testing including high‐resolution manometry and HMII. Defective lower esophageal sphincter (LES) was defined as either LES pressure of <5.0 mmHg, total length of LES of <2.4 cm, or intra‐abdominal length of LES of <0.9 cm. Abnormal esophageal motility was considered present when failed swallows ≥30% and/or mean wave amplitude <30 mmHg was present. HMII used a specialized impedance catheter to directly measure laryngopharyngeal reflux (LPR) and full column reflux (reflux 2 cm distal to the upper esophageal sphincter). Based on the previous study of healthy subjects, abnormal proximal exposure was considered present when LPR ≥1/day and/or full column reflux ≥5/day were present. From October 2009 to June 2011, 46 patients were identified as having pulmonary fibrosis and sufficient HMII data. Of 46, 10 patients were excluded because of concomitant connective tissue diseases, and 8 patients were excluded because they had undergone lung transplantation, which may impact the patterns of reflux. The remaining 28 patients with histologically confirmed IPF (male 16, female 12) were included in this study. Mean age and BMI were 60.4 years (range, 41–78) and 28.4 (range, 21.1–38.1), respectively. All patients except one were symptomatic; 23 (82%) patients had concomitant typical GERD symptoms such as heartburn, whereas 4 (14%) patients had isolated pulmonary symptoms such as cough. Esophageal mucosal injury such as esophagitis and Barrett's esophagus was found in 17 (71%) patients, whereas hiatal hernia was found in 19 (73%) patients. Abnormal proximal exposure, which occurred almost exclusively in the upright position, was present in 54% (15/28) of patients. There was no significant difference in clinical symptoms, objective findings of GERD, and pulmonary functions such as forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), and diffusing capacity of the lung for carbon monoxide (DLCO) between patients with and without abnormal proximal exposure. Although the total number of reflux events was significantly higher in patients with abnormal proximal exposure, a large number of patients had a negative DeMeester score regardless of whether abnormal proximal exposure was present (patients with, 80%; those without, 85%). Patients with abnormal proximal exposure more likely had a defective LES compared with those without (93% vs. 75%). Fourteen patients (56%) had abnormal esophageal motility including aperistaltic esophagus (n = 9). This first study of HMII in patients with IPF demonstrated that GERD is highly prevalent (>70%), and abnormal proximal reflux events such as LPR and full column reflux are common despite a frequently negative DeMeester score. HMII may be beneficial in the work‐up of GERD in patients with IPF.     

The acoustic cough monitoring and manometric profile of cough and throat clearing

Cough and throat clearing might be difficult to differentiate when trying to detect them acoustically or manometrically. The aim of this study was to assess the accuracy of acoustic monitoring for detecting cough and throat clearing, and to also determine whether these two symptoms present with different manometric profiles on esophageal pressure topography. Ten asymptomatic volunteers (seven females, mean age 31.1) were trained to simulate cough and throat clearing in a randomized order every 6 minutes during simultaneous acoustic monitoring and high‐resolution manometry. The accuracy of automated acoustic analysis and two blinded reviewers were compared. The pattern of the events and the duration of the pressure changes were assessed using the 30 mmHg isobaric contour. There were 50 cough and 50 throat‐clearing events according to the protocol. The sensitivity and specificity of automated acoustic analysis was 84% and 50% for cough, while the blinded analysis using sound revealed a sensitivity and specificity of 94% and 92%. The manometric profile of both cough and throat clearing was similar in terms of qualitative findings; however, cough was associated with a greater number of repetitive pressurizations and a more vigorous upper esophageal sphincter contraction compared with throat clearing. The acoustic analysis software has a moderate sensitivity and poor specificity to detect cough. The profile of cough and throat clearing in pressure topography revealed a similar qualitative pattern of pressurization with more vigorous pressure changes and a greater rate of repetitive pressurizations in cough.     

Endodermal/ectodermal interfaces during pharyngeal segmentation in vertebrates

A key event in the formation of the pharyngeal arches is the outpocketing of the endodermal pharyngeal pouches and the establishment of contact with the overlying ectoderm. However, relatively little is known about how the endoderm and ectoderm relate to each other at these points of contact and the extent to which this differs between the pouches. We have therefore detailed the interactions between the pharyngeal pouches and ectoderm in the chick embryo. Unlike the other pouches, the first pouch does not sustain direct contact with the ectoderm but separates after initial contact. Contrastingly, a perforation is formed between the second pouch and cleft that creates an external opening into the pharynx. Finally, the third and fourth pouch endoderm can be seen to bulge outwards through the ectoderm, although external openings to the pharyngeal lumen are not established. To understand whether these behaviours represent derived or ancestral features, we characterised the pharyngeal ectodermal–endodermal interfaces in the shark embryo. We found that the pouches of the posterior gill-bearing arches in this species also displayed the outward bulging of the endoderm into the ectoderm, although openings were established. We further used genetic tools to detail unambiguously the relationship between the endoderm and ectoderm in zebrafish and mouse embryos and again found that the posterior pouches break through the ectoderm. Thus different pharyngeal pouches establish different topological relationships with the overlying ectoderm and the posterior pouches initiate the developmental programme for the formation of gills, be they amniotes or anamniotes.