Usefulness and accuracy of MALDI-TOF mass spectrometry as a supplementary tool to identify mosquito vector species and to invest in development of international database.

Arthropod-borne diseases are important causes of morbidity and mortality. The identification of vector species relies mainly on morphological features and/or molecular biology tools. The first method requires specific technical skills and may result in misidentifications, and the second method is time-consuming and expensive. The aim of the present study is to assess the usefulness and accuracy of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) as a supplementary tool with which to identify mosquito vector species and to invest in the creation of an international database. A total of 89 specimens belonging to 10 mosquito species were selected for the extraction of proteins from legs and for the establishment of a reference database. A blind test with 123 mosquitoes was performed to validate the MS method. Results showed that: (a) the spectra obtained in the study with a given species differed from the spectra of the same species collected in another country, which highlights the need for an international database; (b) MALDI-TOF MS is an accurate method for the rapid identification of mosquito species that are referenced in a database; (c) MALDI-TOF MS allows the separation of groups or complex species, and (d) laboratory specimens undergo a loss of proteins compared with those isolated in the field. In conclusion, MALDI-TOF MS is a useful supplementary tool for mosquito identification and can help inform vector control.

Transmission of multiple resistant Salmonella Concord from internationally adopted children to their adoptive families and social environment: proposition of guidelines.

Since 2004, an increasing number of multidrug-resistant Salmonella serovar Concord infections have been isolated in Belgium among children adopted from Ethiopia. The patients or their family were interviewed and the isolates were subtyped. Between 2004 and 2009, a total of 39 Salmonella Concord infections were isolated from patients. Thirty-four isolates presented a multidrug resistance including resistance to extended-spectrum cephalosporins. Thirty-six cases involved children and 30 of these were adopted from Ethiopia. One case was due to contact with an adopted child and for the other 5 cases no direct epidemiological link with Ethiopia could be found, although four isolates displayed the same patterns observed on the adoptees' isolates, strongly suggesting a phylogenetic relationship with the Ethiopian isolates. Our study confirmed the emergence in Europe of S. Concord isolates resistant to third-generation cephalosporin among Ethiopian adoptees. We have demonstrated that transmission (intra- and extra familial) can happen even if the frequency seems to be low. The presence and the transmission of such a multidrug-resistant Salmonella infection constitute a major concern, since such strains could jeopardize classical antibiotic therapy in patients at risk. This study provides useful information for parents adopting children and for their family practitioner.

Microbiological and epidemiological investigation of the Neisseria meningitidis serogroup A epidemic in Niger in 2009: last wave before the introduction of the serogroup A meningococcal conjugate vaccine?

The 2009 meningitis season in Niger was characterized by an early onset, beginning in the very first weeks of the year and peaking from the 12th to the 15th week with 5655 clinical cases over the 4 weeks. From 1 January 2009 to 28 June 2009 (week 26), a total of 13,733 clinical cases of meningitis were reported to the national epidemiological surveillance system with a case-fatality rate of 4·2%. During the season 25 of the 42 health districts reached the epidemic threshold and 11 the alert threshold. Reactive mass vaccination campaigns involving a total of 5 166,741 doses of the polysaccharide meningococcal bivalent (A+C) vaccine progressively controlled the outbreak in most parts of the country. A total of 3755 cerebrospinal fluid samples representing 28·1% of the suspected meningitis cases were analysed. Serogroup A meningococci were the causative agent in 97·5% of the meningococcal cases. Multi-locus sequence typing of 26 meningococal serogroup A strains showed 25 sequence type (ST)7 and one ST2859, both sequence types belonging to the ST5 clonal complex (CC5) of subgroup III. This is the largest epidemic observed in Niger since those of 1995-1996 (59,948 notified cases) and 2000 (14,633 notified cases).

Surveillance of antibiotic susceptibility patterns among Shigella sonnei strains isolated in Belgium during the 18-year period 1990 to 2007.

This study was conducted to determine the frequency and pattern of antimicrobial susceptibility of Shigella sonnei, the predominant species causing shigellosis in Belgium. Between 1990 and 2007, a total of 7,307 strains, mainly (98.2%) isolated from stools, were diagnosed by peripheral laboratories before being confirmed as Shigella strains by serotyping by the National Reference Center of Salmonella and Shigella. A significant increase in resistances to tetracycline, streptomycin, trimethoprim, sulfonamides, and cotrimoxazole (i.e., trimethoprim in combination with sulfonamides) was observed during this period. Since 1998, resistance to nalidixic acid also increased to reach a peak (12.8%) of resistant isolates in 2004. Concomitantly, multidrug resistance (MDR) in this species emerged in 2007, with 82% of total isolates being MDR. However, during this 18-year period, all isolates remained fully susceptible to ciprofloxacin and gentamicin. The work includes the molecular characterization of mechanisms of resistance to ampicillin, tetracycline, chloramphenicol, and cotrimoxazole and class 1 and class 2 integrons. S. sonnei acquired antimicrobial resistance to traditional antibiotics (ampicillin and tetracycline) by horizontal gene transfer, while the genetic stability of transposons was responsible for a high (89%) proportion of resistance to a commonly prescribed antibiotic (cotrimoxazole). Therefore, cotrimoxazole should no longer be considered appropriate as empirical therapy for treatment of shigellosis in Belgium when antibiotics are indicated. Rates of resistance to nalidixic acid should also be attentively monitored to detect any shift in fluoroquinolone resistance, because it represents the first line among antibiotics used in the treatment of shigellosis.

Drastic decrease of Salmonella Enteritidis isolated from humans in Belgium in 2005, shift in phage types and influence on foodborne outbreaks.

In Belgium, non-typhoidal salmonellosis and campylobacteriosis are the two most frequently reported foodborne illnesses. During 2005, a 71% decrease of Salmonella Enteritidis infections compared with the average annual number cases in the period 2000-2004 was recorded by the Belgian National Reference Centre for Salmonella and Shigella. After the peak of 1999, the total number of salmonellosis cases decreased gradually, with the exception of 2003 when an increase was again recorded due to the rise of isolates belonging to the serotype Enteritidis. PT4, the predominant phage type of serotype Enteriditis over recent years (except in 2003), became the second most prevalent phage type in 2005 after PT21. We present in this paper the epidemiology (incidence and trends) of human salmonellosis in Belgium and assess the role of the vaccination programme in layer flocks on the decline of the incidence of human salmonellosis and foodborne outbreaks due to S. Enteritidis.

A bacterial population study of commercialized wastewater inoculants.

AIMS: To assess the bacterial diversity and safety of wastewater inoculants, which are commercially available products used to improve the aerobic digestion processes of the domestic waste compost in the septic tank. METHODS AND RESULTS: Eighteen wastewater inoculants were analysed on nonselective and selective media and the cultivable bacteria were identified. In all wastewater inoculants, the number of CFUs were between 10(4) and 10(7) g(-1) powder on nonselective media and Bacillus was the predominant cultivable genus. Culture-independent molecular methods such as sequencing of 16S rRNA clone libraries and denaturating gradient gel electrophoresis demonstrated the high prevalence of interfering chloroplast 16S rRNA from plant material and the presence of Bacillus spp. Only after selective enrichments and cultivation, the presence of one pathogenic strain (Klebsiella pneumoniae subsp. pneumoniae) and one opportunistic strain of (Enterobacter cloacae) bacteria were detected in six different products. CONCLUSION: The predominant cultivable species of the wastewater inoculants were Bacillus spp. and after enrichment six products were found to contain opportunistic or pathogenic strains. SIGNIFICANCE AND IMPACT OF THE STUDY: The presence of opportunistic pathogenic strains in the inoculants might represent a risk for immunocompromised, the elderly or children. A clear labelling should therefore be displayed on the product.

[Pet turtle and septicemia: what is the relationship?]. / Tortue d'eau et septicémie chez un nourrisson de 4 mois: quel rapport ?

We report the case of a four months old girl who suffered from a Salmonella pomona's septicemia. The source of contamination was the pet turtle recently acquired by her parents. If the pet turtle-associated salmonellosis is still rare in our country, the high rate of carriage of this germ by these exotic pets and the potential severity of the human disease justify an epidemiological survey. People with immature or weakened immune systems should avoid contact with reptiles.

Isolation of Salmonella from environmental samples collected in the reptile department of Antwerp Zoo using different selective methods.

AIMS: To evaluate the environmental spread of Salmonella strains in the reptile department of Antwerp Zoo and to compare different isolation methods for Salmonella. METHODS AND RESULTS: One hundred environmental samples were collected in the service sections and public spaces of the reptile department. After pre-enrichment in buffered peptone water (BPW), selective enrichment was performed in Rappaport Vassiliadis Single Component Enrichment Broth (RVS), Selenite Cystine Broth (SEL) and Mueller Kauffman Tetrathionate Broth (MKTTn). Subculturing on Modified Semisolid Rappaport-Vassiliadis (MSRV) Medium, and the combined use of immunomagnetic separation (IMS) and RVS was evaluated. The isolation media used were Hektoen Enteric Agar (HE), Phenol Red Brilliant Green Agar (BG) and Xylose Lysine Decarboxylase Agar (XLD). Salmonella strains were found in 47 samples (47.0%). Most isolations were made on HE after combined IMS/RVS enrichment. Sixty-six Salmonella strains were serotyped, 29 belonged to Salmonella enterica ssp. enterica (I), 3 to ssp. salamae (II), 29 to ssp. arizonae or diarizonae (IIIa/b), 4 to ssp. houtenae (IV) and 1 strain showed autoagglutination. In addition, a 10-year survey (1995-2004) of Salmonella serovars isolated from reptiles at Antwerp Zoo is presented. CONCLUSIONS: A high prevalence of Salmonella strains was noted in the service sections of the reptile department. Only a few isolations were made in the public spaces. Selective enrichment in RVS was the most efficient. In combination with IMS, this method gave an even higher isolation rate than the International Standard method (ISO 6579:2002). SIGNIFICANCE AND IMPACT OF THE STUDY: This study confirms the importance of reptiles as spreaders of Salmonella in their surroundings. The possible infectious risks for zoo personnel and visitors are evaluated. Improved laboratory protocols for the isolation of Salmonella from the environment are suggested.

[Duodenogastric and gastroesophageal bile reflux]. / Le reflux biliaire duodéno-gastrique et gastro-oesophagien.

This study reviews current data regarding duodenogastric and gastroesophageal bile reflux-pathophysiology, clinical presentation, methods of diagnosis (namely, 24-hour intraluminal bile monitoring) and therapeutic management. Duodenogastric reflux (DGR) consists of retrograde passage of alkaline duodenal contents into the stomach; it may occur due to antroduodenal motility disorder (primary DGR) or may arise following surgical alteration of gastoduodenal anatomy or because of biliary pathology (secondary DGR). Pathologic DGR may generate symptoms of epigastric pain, nausea, and bilious vomiting. In patients with concomitant gastroesophageal reflux, the backwash of duodenal content into the lower esophagus can cause mixed (alkaline and acid) reflux esophagitis, and lead, in turn, to esophageal mucosal damage such as Barrett's metaplasia and adenocarcinoma. The treatment of DGR is difficult, non-specific, and relatively ineffective in controlling symptoms. Proton pump inhibitors decrease the upstream effects of DGR on the esophagus by decreasing the volume of secretions; promotility agents diminish gastric exposure to duodenal secretions by improving gastric emptying. In patients with severe reflux resistant to medical therapy, a duodenal diversion operation such as the duodenal switch procedure may be indicated.

Salmonella enterica subspecies houtenae serotype 44:z4, z23:--as a rare cause of meningitis.

Reptiles can carry and shed the bacterium Salmonella without showing any signs of illness. Transmission occurs by ingesting Salmonella after handling a reptile or objects contaminated by a reptile. Young children are especially vulnerable to Salmonella infection and can experience serious complications. We describe a case of reptile-associated Salmonella meningitis in a 2.5-month-old infant.

Antimicrobial drug resistance in nontyphoid human Salmonella in Belgium: trends for the period 2000-2002.

In order to assess antimicrobial resistance in nontyphoid human Salmonella in Belgium, the six most important serovars, representing together more than 90% of laboratory confirmed cases, were randomly sampled. From June 2000 until December 2002, a total of 1756 isolates were screened for their antimicrobial resistance profile by the disc diffusion method. S. Hadar strains showed the highest level of antimicrobial resistance. Simultaneous resistance to ampicillin, nalidixic acid, tetracycline and streptomycin was observed in 81.5, 58 and 76.1% of these isolates in 2000, 2001 and 2002, respectively. All S. Hadar isolates resistant to nalidixic acid also displayed decreased susceptibility to ciprofloxacin (MIC50 values of 0.25 microg/mL in 2000-2001 and 0.19 microg/mL in 2002). In 2000, 2001 and 2002, respectively 44.6, 46 and 36.5% of S. Typhimurium isolates were multiresistant (resistant to 4 or more antimicrobial agents). These multiresistant isolates were preferably associated with a few phage types, such as DT104. Complete resistance to ciprofloxacin was detected in three S. Typhimurium isolates and sequencing of the gyrA gene revealed for each isolate two mutations at codons corresponding to Ser-83 and Asp-87. Multiresistance was also common in S. Virchow (7.7%, 15.9% and 29.7%, in 2000, 2001 and 2002, respectively). Resistance to nalidixic acid in S. Virchow isolates increased from 46.2% in 2000 to 80.9% in 2002 and six S. Virchow isolates were detected as cefotaxime resistant. In contrast, the vast majority of S. Enteritidis, S. Brandenburg and S. Derby isolates remained sensitive to almost all antimicrobial agents tested.

Whole stomach with antro-pyloric nerve preservation as an esophageal substitute: an original technique.

The paper describes an original technique of gastric tailoring in which the two-thirds of the lesser curvature proximal to the crow's foot are denuded flush with the gastric wall, leaving both nerves of Latarjet and the hepatic branches of the left vagus nerve intact. Maintenance of the vagal supply to the antro-pyloric segment in two patients resulted in the presence of peristaltic contractions sweeping over the antrum on simple observation of the antral wall at the end of the procedure and on both upper G-I series and intragastric manometry tracings 6 weeks postoperatively. Gastric exposure to bile on 24-h gastric bile monitoring was normal 6 weeks after the operation. Neither patient had any gastrointestinal symptoms with the exception of early sensations of postprandial fullness when overeating.

Oesophageal and gastric bile exposure after gastroduodenal surgery with Henley's interposition or a Roux-en-Y loop.

BACKGROUND: The degree which the various reconstruction techniques prevent bile reflux after gastroduodenal surgery has been poorly studied. METHODS: Bile exposure in the intestinal tract just proximal to the jejunal loop was measured with the Bilitec 2000 device for 24 h after gastroduodenal surgery in three groups of patients. Group 1 comprised 24 patients with a 60-cm Henley's loop after total gastrectomy. Group 2 included 31 patients with a 60-cm Roux-en-Y loop after total (22 patients) or subtotal (nine) gastrectomy. Group 3 contained 21 patients with a 60-cm Roux-en-Y loop anastomosed to the proximal duodenum as part of a duodenal switch operation for pathological transpyloric duodenogastric reflux. Bile exposure, measured as the percentage time with bile absorbance greater than 0.25, was classified as nil, within the range of a control population of healthy subjects, or pathological (above the 95th percentile for the control population). Reflux symptoms were scored and all patients had upper gastrointestinal endoscopy. RESULTS: Bile was detected in the intestine proximal to the loop in none of 24 patients in group 1, eight of 31 in group 2 and 12 of 21 in group 3 (P < 0.001). The mean reflux symptom score increased with the degree of bile exposure, and the proportion of patients with oesophagitis or gastritis correlated well with the extent of bile exposure (P < 0.001). CONCLUSION: A long Henley's loop was more effective in preventing bile reflux than a long Roux-en-Y loop. Bilitec data correlated well with the severity of reflux symptoms and the presence of mucosal lesions.

Gentamicin resistance genes in environmental bacteria: prevalence and transfer.

A comprehensive multiphasic survey of the prevalence and transfer of gentamicin resistance (Gm(r)) genes in different non-clinical environments has been performed. We were interested to find out whether Gm(r) genes described from clinical isolates can be detected in different environmental habitats and whether hot spots can be identified. Furthermore, this study aimed to evaluate the impact of selective pressure on the abundance and mobility of resistance genes. The study included samples from soils, rhizospheres, piggery manure, faeces from cattle, laying and broiler chickens, municipal and hospital sewage water, and coastal water. Six clusters of genes coding for Gm-modifying enzymes (aac(3)-I, aac(3)-II/VI, aac(3)-III/IV, aac(6')-II/Ib, ant(2'')-I, aph(2'')-I) were identified based on a database comparison and primer systems for each gene cluster were developed. Gm-resistant bacteria isolated from the different environments had a different taxonomic composition. In only 34 of 207 isolates, mainly originating from sewage, faeces and coastal water polluted with wastewater, were known Gm(r) genes corresponding to five of the six clusters detected. The strains belonged to genera in which the genes had previously been detected (Enterobacteriaceae, Pseudomonas, Acinetobacter) but also to phylogenetically distant bacteria, such as members of the CFB group, alpha- and beta-Proteobacteria. Gm(r) genes located on mobile genetic elements (MGE) could be captured in exogenous isolations into recipients belonging to alpha-, beta- and gamma-Proteobacteria from all environments except for soil. A high proportion of the MGE, conferring Gm resistance isolated from sewage, were identified as IncPbeta plasmids. Molecular detection of Gm(r) genes, and broad host range plasmid-specific sequences (IncP-1, IncN, IncW and IncQ) in environmental DNA indicated a habitat-specific dissemination. A high abundance and diversity of Gm(r) genes could be shown for samples from faeces (broilers, layers, cattle), from sewage, from seawater, collected close to a wastewater outflow, and from piggery manure. In the latter samples all six clusters of Gm(r) genes could be detected. The different kinds of selective pressure studied here seemed to enhance the abundance of MGE, while an effect on Gm(r) genes was not obvious.

[Esophagitis secondary to jejuno-esophageal reflux after total gastrectomy and Roux-en-Y loop]. / OEsophagite par reflux jéjuno-oesophagien après gastrectomie totale et anse de Roux en Y.

We report a case of esophagitis secondary to jejuno-esophageal reflux after total gastrectomy and 60 cm Roux-en-Y jejunal loop. Both esophagitis and jejuno-esophageal reflux disappeared after lengthening of the Y-loop by 50 cm.

Skeletonizing en bloc esophagectomy for cancer.

OBJECTIVE: To evaluate the long-term outcome of patients with esophageal cancer after resection of the extraesophageal component of the neoplastic process en bloc with the esophageal tube. SUMMARY BACKGROUND DATA: Opinions are conflicting about the addition of extended resection of locoregional lymph nodes and soft tissue to removal of the esophageal tube. METHODS: Esophagectomy performed en bloc with locoregional lymph nodes and resulting in a real skeletonization of the nonresectable anatomical structures adjacent to the esophagus was attempted in 324 patients. The esophagus was removed using a right thoracic (n = 208), transdiaphragmatic (n = 39), or left thoracic (n = 77) approach. Lymphadenectomy was performed in the upper abdomen and lower mediastinum in all patients. It was extended over the upper mediastinum when a right thoracic approach was used and up to the neck in 17 patients. Esophagectomy was carried out flush with the esophageal wall as soon as it became obvious that a macroscopically complete resection was not feasible. Neoplastic processes were classified according to completeness of the resection, depth of wall penetration, and lymph node involvement. RESULTS: Skeletonizing en bloc esophagectomy was feasible in 235 of the 324 patients (73%). The 5-year survival rate, including in-hospital deaths (5%), was 35% (324 patients); it was 64% in the 117 patients with an intramural neoplastic process versus 19% in the 207 patients having neoplastic tissue outside the esophageal wall or surgical margins (P <.0001). The latter 19% represented 12% of the whole series. The 5-year survival rate after skeletonizing en bloc esophagectomy was 49% (235 patients), 49% for squamous cell versus 47% for glandular carcinomas (P =.4599), 64% for patients with an intramural tumor versus 34% for those with extraesophageal neoplastic tissue (P <.0001), and 43% for patients with fewer than five metastatic nodes versus 11% for those with involvement of five or more lymph nodes (P =.0001). CONCLUSIONS: The strategy of attempting skeletonizing en bloc esophagectomy in all patients offers long-term survival to one third of the patients with resectable extraesophageal neoplastic tissues. These patients represent 12% of the patients with esophageal cancer suitable for esophagectomy and 19% of those having neoplastic tissue outside the esophageal wall or surgical margins.

Bile exposure of the denervated stomach as an esophageal substitute.

BACKGROUND: Both the supine position and the existence of a gastric drainage procedure are suspected to promote reflux of duodenal juice into the denervated intrathoracic stomach. Erythromycin has been shown to weaken pyloric resistance to gastric outflow and to enhance antral motility, gastric emptying, and gallbladder contractility. METHODS: The presence of bile in the gastric transplant of 79 patients was monitored over a 24-hour period with use of the Bilitec 2000 optoelectronic device 3 to 195 months after subtotal esophagectomy. Ten patients were reinvestigated after a 3-year period. Five groups were studied: group I: n = 12, no gastric drainage, never given erythromycin, group 2: n = 40, gastric drainage, never given erythromycin, group 3: n = 7, no gastric drainage, given erythromycin, group 4: n = 13, gastric drainage, given erythromycin, and group 5: n = 7, no longer given erythromycin (with or without gastric drainage). The percentage of time gastric bile absorbance was more than 0.25 was calculated for the total, supine, and upright periods of recording in reference to data from 25 healthy volunteers. RESULTS: The Bilitec test was pathologic in 9 of the 12 patients of group 1 whereas it was normal in three. Gastric exposure to bile was longer in group I patients than in controls for the total (p = 0.012) and supine (0.036) periods, but the difference did not reach statistical significance for the upright period (p = 0.080). Bile exposure in group 4 did not significantly differ from controls (total: p = 0.701; supine: p = 0.124; upright: p = 0.712). Bile exposure for the total period did not significantly differ whether patients were taking erythromycin or the drug had been discontinued at the time of the study (p = 0.234); and it tended to decrease with time in patients investigated twice (p = 0.046). CONCLUSIONS: Gastric exposure to bile after truncal vagotomy and transposition of the stomach up to the neck is pathologic in three quarters of patients. It is more marked in the supine than in the upright position and tends to decrease with time. The addition of a gastric drainage procedure in combination with erythromycin therapy tends to normalize gastric exposure to bile. The effects of erythromycin may persist after discontinuation of the drug.

Human stomach has a recordable mechanical activity at a rate of about three cycles/minute.

OBJECTIVE: To discover whether the human stomach contracts every 20 seconds or not. DESIGN: Manometric study. SETTING: Teaching hospital, Belgium. SUBJECTS: 10 healthy volunteers, and 31 patients who had had the whole stomach denervated and pulled up to the neck for oesophageal replacement. INTERVENTIONS: Analysis of selected strips of manometric tracings obtained with intraluminal perfused catheters. 13 patients were given erythromycin (1 g/day) by mouth. MAIN OUTCOME MEASURES: Estimation of the rate and frequency distribution according to amplitude of intraluminal pressure waves with the vertical axis of the tracings scaled up to reflect contractions within the gastric wall. RESULTS: Microwaves (<9 mmHg) that came in between conventional macrowaves (>9 mmHg) were found, showing that the human stomach undergoes mechanical activity (amplitude ranging from 0.2-310 mmHg) at the pacemaker's rate which varied from 2.43 to 3.60 cycles/minute from one subject to another. Phase I of the interdigestive motor complex contained microwaves only, phase II and the fed pattern consisted of a mixture of microwaves and macrowaves, and phase III contained macrowaves only. The fasting rate of mechanical activity was lower in patients who were given erythromycin than in those not given erythromycin (p = 0.003) and in healthy volunteers (p=0.002), and it increased significantly after a meal (p < 0.0001). Microwaves in strips in which they were the most prominent were of higher amplitude in patients than in healthy volunteers (median: 3.5 compared with 2.5 mmHg; p < 0.0001). CONCLUSIONS: The human stomach has mechanical activity at the rate at which the pacemaker generates electrical slow waves. The classic phases of the gastric motor activity seem to differ from each other by the frequency distribution of pressure waves according to amplitude rather than by the contraction rate. Weak mechanical activity is much more readily detectable after the stomach has been denervated and tailored for oesophageal substitution.

Denervated stomach as an esophageal substitute recovers intraluminal acidity with time.

OBJECTIVE: To determine whether the denervated stomach as an esophageal substitute recovers normal intraluminal acidity with time. SUMMARY BACKGROUND DATA: Bilateral truncal vagotomy to the stomach as an esophageal substitute reduces both gastric acid production and antral motility, but a spontaneous motor recovery process takes place over years. METHODS: Intraluminal gastric pH and bile were monitored during a 24-hour period 1 to 195 months after transthoracic elevation of the stomach as esophageal replacement in 91 and 76 patients, respectively. Nine patients underwent a second gastric pH monitoring after a 3-year period. The percentages of time that the gastric pH was less than 2 and bile absorbance exceeded 0.25 were calculated in reference to values from 25 healthy volunteers. Eighty-nine upper gastrointestinal endoscopies were performed in 83 patients. Patients were divided into three groups depending on length of follow-up: group 1, less than 1 year; group 2, 1 to 3 years; group 3, more than 3 years. RESULTS: The prevalence of a normal gastric pH profile was 32.3% in group 1, 81.5% in group 2, and 97.6% in group 3. The percentage of time that the gastric pH was less than 2 increased from group 1 (27.3%) to group 2 (56.1%) and group 3 (70.5%), parallel to an increase in the prevalence of cervical heartburn and esophagitis. The percentage of time that the gastric pH was less than 2 increased from 28.7% to 81.2% in the nine patients investigated twice. Exposure of the gastric mucosa to bile was 12.8% in patients with a high gastric pH profile versus 19.3% in those with normal acidity. In the esophageal remnant in six patients, Barrett's metaplasia developed, intestinal (n = 2) or gastric (n = 4) in type. CONCLUSIONS: Early after vagotomy, intraluminal gastric acidity is reduced in two thirds of patients, but the stomach recovers a normal intraluminal pH profile with time, so that in more than one third of patients, disabling cervical heartburn and esophagitis develop. The potential for the development of Barrett's metaplasia in the esophageal remnant brings into question the use of the stomach as an esophageal substitute in benign and early neoplastic disease.