Efficacy of a Clinical Decision Rule to Enable Direct Oral Challenge in Patients With Low-Risk Penicillin Allergy: The PALACE Randomized Clinical Trial

Importance

Fewer than 5% of patients labeled with a penicillin allergy are truly allergic. The standard of care to remove the penicillin allergy label in adults is specialized testing involving prick and intradermal skin testing followed by an oral challenge with penicillin. Skin testing is resource intensive, limits practice to specialist-trained physicians, and restricts the global population who could undergo penicillin allergy delabeling.

Objective

To determine whether a direct oral penicillin challenge is noninferior to the standard of care of penicillin skin testing followed by an oral challenge in patients with a low-risk penicillin allergy.

Design, Setting, and Participants

This parallel, 2-arm, noninferiority, open-label, multicenter, international randomized clinical trial occurred in 6 specialized centers, 3 in North America (US and Canada) and 3 in Australia, from June 18, 2021, to December 2, 2022. Eligible adults had a PEN-FAST score lower than 3. PEN-FAST is a prospectively derived and internationally validated clinical decision rule that enables point-of-care risk assessment for adults reporting penicillin allergies.

Interventions

Patients were randomly assigned to either direct oral challenge with penicillin (intervention arm) or a standard-of-care arm of penicillin skin testing followed by oral challenge with penicillin (control arm).

Main Outcome and Measure

The primary outcome was a physician-verified positive immune-mediated oral penicillin challenge within 1 hour postintervention in the intention-to-treat population. Noninferiority was achieved if a 1-sided 95% CI of the risk difference (RD) did not exceed 5 percentage points (pp).

Results

A total of 382 adults were randomized, with 377 patients (median [IQR] age, 51 [35-65] years; 247 [65.5%] female) included in the analysis: 187 in the intervention group and 190 in the control group. Most patients had a PEN-FAST score of 0 or 1. The primary outcome occurred in 1 patient (0.5%) in the intervention group and 1 patient (0.5%) in the control group, with an RD of 0.0084 pp (90% CI, -1.22 to 1.24 pp). The 1-sided 95% CI was below the noninferiority margin of 5 pp. In the 5 days following the oral penicillin challenge, 9 immune-mediated adverse events were recorded in the intervention group and 10 in the control group (RD, -0.45 pp; 95% CI, -4.87 to 3.96 pp). No serious adverse events occurred.

Conclusions and Relevance

In this randomized clinical trial, direct oral penicillin challenge in patients with a low-risk penicillin allergy was noninferior compared with standard-of-care skin testing followed by oral challenge. In patients with a low-risk history, direct oral penicillin challenge is a safe procedure to facilitate the removal of a penicillin allergy label.

Trial Registration

ClinicalTrials.gov Identifier: NCT04454229.

POS0402 CLONALLY EXPANDED CD38hi CYTOTOXIC CD8 T CELLS DEFINE THE T CELL INFILTRATE IN CHECKPOINT INHIBITOR-ASSOCIATED ARTHRITIS

Background

Immune checkpoint inhibitor (ICI) therapies that promote T cell activation have improved outcomes for advanced malignancies yet can also elicit harmful autoimmune reactions. The T cell mechanisms mediating these iatrogenic autoimmune events remain unclear.

Objectives

To investigate the immunophenotype, transcriptomic feature and clonotypes of T cells from joints of patients affected by ICI-induced inflammatory arthritis (ICI-arthritis).

Methods

Detailed immunophenotyping was performed on mononuclear cells from synovial fluid (SF) using mass cytometry and flow cytometry to identify significantly altered populations in ICI-A compared to seropositive rhrumatoid arthritis (RA) and psoriatic arthritis (PsA) (p<0.05). Bulk RNA-seq was performed on altered SF CD8 T cell subsets from ICI-A, RA and PsA to investigate their transcriptomic features. Cytokine profile and pathways enriched in ICI-A CD8 T cells were examined using differentially expressed genes, intracellular staining, and in vitro culture. TCR clonotypes were examined using single cell RNA-seq of T cells from synovial fluid, tissue and blood of ICI-A.

Results

Compared to the autoimmune arthritides RA and PsA, ICI-arthritis joints contained an expanded CD38hi CD127- CD8+ T cell subset that displays cytotoxic, effector, and interferon (IFN) response signatures. Exposure of synovial T cells to Type I IFN, more so than IFN-γ, induced the CD38hi cytotoxic phenotype. Single cell transcriptomic and T cell repertoire (TCR) analyses indicated that the abundance of CD38hi CD8 T cells in ICI-arthritis resulted from proliferation of a limited number of clones. The CD38hi population appeared distinct from dysfunctional T cells and clonally most related to TCF7+ memory populations. Comparison of synovial tissue from bilateral knees of the same patient demonstrated considerable sharing of TCR clonotypes among CD38hi CD8 T cells between the two joints. Further, TCR clonotypes expanded in synovial fluid of ICI-arthritis patients were detected in circulating T cells, and circulating CD38hi CD8 T cells are also expanded in ICI-arthritis patients.

Conclusion

These results define a distinct CD8 T cell subset in the synovial fluid and in the circulation of patients with ICI-A that may be directly activated by ICI therapy to mediate a tissue-specific autoimmune response.

Disclosure of Interests

None declared.

Allergic Reactions to the COVID-19 vaccine (ARCOV) study: the McGill University Health Center (MUHC) experience

Background

Messenger RNA coronavirus disease 2019 (COVID-19) vaccines have been associated with allergic reactions. A history of anaphylaxis has been suggested as a risk factor for such reactions. Polyethylene glycol (PEG) has been proposed as a possible culprit allergen.

Objective

To investigate possible PEG or polysorbate allergy among patients reporting prior reactions to COVID-19 vaccines or PEG and to report their subsequent tolerance of COVID-19 vaccines.

Methods

From January 1, 2021, to October 31, 2021, adult patients referred to the McGill University Health Centre allergy clinics who were considered at risk of anaphylaxis were prospectively recruited. The entry criteria were any documented history of reaction to a COVID-19 vaccine or reported allergy to PEG or polysorbate. Evaluated patients underwent skin prick testing (SPT) with PEG and polysorbate. After SPT, placebo-controlled vaccine challenges were carried out.

Results

Of the 44 patients recruited, 40 (90.1%) had reacted to the first vaccine dose, with 18 (45%) of them had anaphylactic reaction. All patients underwent SPT and 5 (11.3%) had a positive test result. A total of 39 patients (88.6%) underwent COVID-19 vaccine challenge at the allergy clinic. Most tolerated the vaccine, with 18 (40.1%) received a single full dose, 20 (45.4%) 2 split doses, and 6 (13.6%) a graded dosing protocol. Of the 40 patients who reacted to the first dose, 2 had immediate nonsevere allergic reactions to the second dose.

Conclusion

In this cohort of patients with a history of anaphylaxis and increased risk of allergic reactions to the COVID-19 vaccines, after allergist evaluation, including negative PEG skin testing result, the vaccine was safely administered without any serious adverse events.

Successful Desensitization to mRNA COVID-19 Vaccine in a Case Series of Patients With a History of Anaphylaxis to the First Vaccine Dose

Background

Coronavirus disease 2109 (COVID-19) vaccines have recently been approved to curb the global pandemic. The risk of allergic reactions to the vaccine polyethylene glycol (PEG) component has raised significant public concern. Desensitization is suggested in cases of vaccine related hypersensitivity reactions. After comprehensive literature review on the topic, our aim was to establish a safe and effective desensitization protocol for patients with suspected or confirmed immediate type hypersensitivity reactions to the COVID-19 vaccine.

Methods

Participants were referred to the McGill University Health Center (MUHC) Allergy-Immunology department for clinical evaluation following a reported reaction to their first dose of Moderna® mRNA-1273 or Pfizer-BioNTech® BNT162b2 vaccines. They underwent skin prick testing (SPT) with higher and lower molecular weight (MW) PEG and polysorbate 80, as per published protocols. Their second dose was administered following a desensitization protocol consisting of multiple dose-administration steps followed by a 60-min observation period.

Results

Among a cohort of 142 patients with an increased risk for allergic reactions to the COVID-19 vaccines, six individuals were selected to undergo desensitization. All were female with allergic background including chronic spontaneous urticaria, anaphylaxis to medications, and/or vaccines. The main symptom after their first dose was difficulty swallowing with lightheadedness or immediate urticaria, angioedema, and/or dizziness. Two patients had positive skin testing. One patient was on chronic antihistamines which resulted in an inconclusive PEG skin test and the skin testing was negative for the three other patients. During the desensitization, two patients reported cutaneous symptoms of an immediate reaction and were managed with antihistamines. One of these patients also complained of ear pressure and had a drop in her systolic blood pressure, treated with intravenous fluids.

Conclusion

This study suggests that some individuals with an immediate-type hypersensitivity reaction to their first dose of mRNA COVID-19 vaccine may safely receive their second dose using a desensitization protocol. The success of this desensitization protocol is a step forward in the fight against COVID-19, allowing more individuals to be immunized.

Alloplastic bypass material below the knee: actual rationale

AIM

The greater saphenous vein is considered as material of first choice for a below-knee bypass. A high number of below knee synthetic, polytetrafluoroethylene or knitted polyester, bypass grafts in the institution of the senior author formed the basis to analyze factors for outcome of below-knee synthetic grafts.

METHODS

A total of 533 patients (327 men, 206 women; age: 71.2 ± 10.3 years), who had their first below knee bypass, were followed-up for up-to 9 (4.1 ± 2.6) years. Survival, primary and secondary patency, and limb salvage were compared between vein bypasses and synthetic grafts by Kaplan Meier analysis. Within the group of 377 patients with synthetic grafts comorbidities, previous interventions, indications, graft diameter, and technical aspects were related to outcome including univariate (log-rank) and multivariate (Cox Proportional Hazard Ratio) statistics.

RESULTS

The greater saphenous vein was superior to synthetic graft in primary and secondary patency as well as limb salvage (5 year limb salvage 73.3% vs. 56.7%, P=0.001). In patients with a synthetic bypass, relevant preoperative factors for higher patency rates were hypertension, coronary heart disease and no previous endovascular intervention. Patency and limb salvage was significantly improved for anastomoses not to a single crural vessel. Adding a St. Mary's Boot as cuff technique did not improve the results. In multivariate analysis, independent factors for higher primary patency were no previous endovascular intervention, low severity of peripheral arterial occlusive disease, coronary heart disease and age above 65. Additionally, femoropopliteal and tibioperoneal anastomoses were related to better limb salvage.

CONCLUSION

The greater saphenous vein reveals the best results for below-knee bypass grafts. However, if a vein is not available, synthetic grafts appear to be an valuable alternative especially in patients with no previous radiologic intervention, coronary heart disease, and age over 65.

Comparison of the influence of plastic and fully covered metal biliary stents on the accuracy of EUS-FNA for the diagnosis of pancreatic cancer

BACKGROUND AND STUDY AIMS

Prior studies have reported that the presence of prior biliary stent may interfere with EUS visualization of pancreatic tumors. We aimed to compare the influence of the biliary plastic and fully covered self-expanding metal stents (CSEMS) on the accuracy of EUS-FNA cytology in patients with solid pancreatic masses.

PATIENTS AND METHODS

We conducted a retrospective study evaluating 677 patients with solid pancreatic head/uncinate lesions and a previous biliary stent in whom EUS-FNA was performed. The patients were stratified into two groups: (1) those with a plastic stents and (2) those with CSEMS. Performance characteristics of EUS-FNA including the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were compared between the two groups.

RESULTS

The frequency of obtaining an adequate cytology by EUS-FNA was similar in both the CSEMS group and the plastic stent group (97 vs. 97.1 % respectively; p = 1.0). The sensitivity, specificity, and accuracy of EUS-FNA was not significantly different between patients with CSEMS and plastic stents (96.8, 100, 100 % and 97.3, 98, 99.8 %, respectively). The negative predictive value for EUS-FNA was lower in the CSEMS group compared to the plastic stent group (66.6 vs. 78.1 % respectively; p = 0.42). There was one false-positive cytology in the plastic stent group compared to none in the CSEMS group.

CONCLUSIONS

In a retrospective cohort trial, EUS-FNA was found to be highly accurate and safe in diagnosing patients with suspected pancreatic cancer, even in the presence of a plastic or metallic biliary stent. The presence of a stent did not contribute to a higher false-positive cytology rate.

[Comment on the article "Operative Techniques and Outcomes in Metabolic Surgery: Sleeve Gastrectomy"]

The review article "Operative Techniques and Outcomes in Metabolic Surgery: Sleeve Gastrectomy" by Hüttl et al. is concerned with laparoscopic sleeve stomach operations ("sleeve gastrectomy") for the surgical treatment of morbid obesity (Zentralblatt für Chirurgie 2009; 134: 24-31). After an analysis of the available literature and own results, the authors concluded that the laparoscopic sleeve operation is established today as an effective standard procedure in the therapy for obesity.We would like to comment on the content of this article.

[Metastasis of an esophageal carcinoma at a PEG site--case report and review of the literature]

We describe the case of a 54-year-old man with a tumour of the proximal esophagus (cT3-4,N1,M0), who underwent percutaneous endoscopic gastrostomy (PEG) for enteral feeding. Primary radiochemotherapy was initiated shortly after PEG insertion. Five months after PEG insertion the patient detected a nodule at the site. The general practitioner diagnosed this nodule as a brotic reaction. Another six weeks later, ulceration that had grown along the PEG probe at the PEG site was observed on gastroscopy. The primary tumour was not visible. Histological examination showed an abdominal wall metastasis of the esophageal cancer. Despite subtotal gastrectomy with en-bloc resection of the tumour, distant metastasis developed. The patient died six months after surgery. About 47 cases of abdominal wall metastases as late complications at the site have been reported until now. The mechanism of tumour spread of PEG site is a subject of controversial discussion. As direct mechanical tumour implantation is the most likely mechanism, an alternative method like operative (laparoscopic) or radiological PEG placement should be considered in cases with advanced, stenotic tumours.

Tumor cell dissemination in a human colon cancer animal model: orthotopic implantation or intraportal injection?

BACKGROUND

The development of therapeutic strategies for treatment of metastasized colorectal carcinoma requires biologically relevant and adequate animal models generating both metastases and the dissemination of tumor cells.

METHODS

To prove the efficiency of orthotopic implantation concerning induction of minimal residual disease (MRD) colorectal cancer tissue from 10 patients was transplanted orthotopically into nude mice. In the intraportal injection model 1 x 10(6) HT-29 human colon cancer cells were injected. We investigated by histological studies and CK-20 RT-PCR the occurrence of hematogenous metastases and the dissemination of human colon cancer cells in bone marrow.

RESULTS

Following orthotopic implantation of human colon cancer tissue the lymph node and hepatic metastasis rates were low. MRD as reflected by CK-20 positivity of the bone marrow was present in 22.2%. The intraportal injection of 1 x 10(6) HT-29 human colon cancer cells produced hepatic metastases in up to 89% of all animals. The intraportal injection of 1 x 10(6) cells also generated MRD in the bone marrow in 63% of animals.

CONCLUSIONS

The intraportal injection model represents a biologically relevant and adequate animal model for the induction of both reproducible hepatic metastasis and MRD in the bone marrow. In this regard it seems to be superior to the orthotopic implantation model.

[Less reflux recurrence following Nissen fundoplication : results of laparoscopic antireflux surgery after 10 years]

BACKGROUND

Reflux recurrence is the most common long-term complication following fundoplication. Results for different techniques of laparoscopic antireflux surgery were retrospectively compared after 10 years.

METHODS

From 1992 to 1997, the 120 patients studied had laparoscopic fundoplication with 'tailored' approaches: 88 Nissen, 22 anterior, and ten Toupet fundoplications. Follow-up of 87% of these patients included disease-related questions and the gastrointestinal quality of life index (GIQLI).

RESULTS

Of the patients, 89% would select surgery again. Regurgitations after fundoplication were noted from 15% of patients after Nissen, 44% after anterior, and 10% after Toupet types (P=0.04). Twenty-eight percent were on acid suppression therapy. Proton pump inhibitors were used less frequently following Nissen fundoplication (P=0.01). The GIQLI score was 110+/-24 without significant differences for type of fundoplication.

DISCUSSION

Overall results are satisfactory after 10 years of experience with fundoplication. Total fundoplication appears to control reflux better than partial fundoplication.

Ten-year outcome of laparoscopic antireflux surgery

BACKGROUND

Reflux recurrence is the most common long-term complication of fundoplication. Its frequency was independent from the type of fundoplication in randomized studies. Results for different techniques of laparoscopic antireflux surgery were retrospectively evaluated after 10 years.

METHODS

From 1992 to 1997, 120 patients had primary laparoscopic fundoplication with a "tailored approach" (type of wrap chosen according to esophageal peristalsis): 88 received a Nissen, 22 an anterior, and 10 a Toupet fundoplication. Follow-up of 87% of the patients included disease-related questions and the gastrointestinal quality-of-life index (GIQLI).

RESULTS

Of the patients, 89% would select surgery again. Heartburn was reported by 30% of the patients. Regurgitations were noted from 15% of patients after a Nissen, 44% after anterior fundoplication, and 10% after a Toupet (p = 0.04). Twenty-eight percent were on acid-suppressive drugs again. Following Nissen fundoplication, proton pump inhibitors were less frequently used (p = 0.01) and on postoperative pH-metry reflux recurrence rate was lower (p = 0.04). The GIQLI was 110 +/- 24 without significant differences for the type of fundoplication.

DISCUSSION

Ten years after laparoscopic fundoplication, overall outcome is good. A quarter of the patients are on acid-suppressive drugs. Nissen fundoplication appears to control reflux better than a partial fundoplication.

[Antibody treatment in colorectal cancer--what the surgeon needs to know]

Advances in the medical treatment of colorectal cancer patients have resulted in considerable improvements through the introduction of new cytotoxic drugs. The significant progress in molecular and tumour biology has produced a great number of targeted, tumour-specific, monoclonal antibodies that are now in various stages of clinical development. Two of these antibodies, cetuximab (Erbitux) und bevacizumab (Avastin), directed against the epidermal growth factor receptor (EGFR) and the vascular epithelial growth factor (VEGF), respectively, have recently been approved for use in metastatic colorectal cancer. The combination of well-known and newly developed cytotoxic agents with monoclonal antibodies makes the medical treatment of colorectal cancer patients considerably more complex, but also provides additional therapeutic strategies for patients in advanced stages of disease.

[Intrapancreatic accessory spleen: a differential diagnosis of pancreatic tumour]

BACKGROUND

According to autoptic studies, accessory spleens may be found in 10-15% of the population and most of them are usually located at or near the splenic hilum. Only in 1-2% they are located in the pancreatic tail. We report a rare case of intrapancreatic accessory spleen which radiologically mimicked a tumor in the tail of the pancreas.

PATIENT

A 54-year-old man was diagnosed with a tumor at the pancreatic tail. In the preoperative computed tomography (CT), there was a lesion (2.6 cm in diameter) in the pancreatic tail and two locoregional lesions (1 and 1.5 cm in diameter), which had intensive contrast enhancement. The diagnosis of a nonfunctioning endocrine pancreatic tail carcinoma with lymph node metastasis was made.

RESULTS

Intraoperative examination showed two accessory spleens nearby the pancreatic tail. As pancreatic cancer could not be excluded because of the local findings, an oncological left pancreatectomy was performed. Histological examination excluded cancer and revealed an intrapancreatic accessory spleen and two accessory spleens nearby the pancreatic tail.

CONCLUSION

Intrapancreatic accessory spleen should be included in the differential diagnosis of pancreatic neoplasm.

Importance of duodenogastric reflux in gastro-oesophageal reflux disease

BACKGROUND

Bile in the oesophagus occurs frequently in patients with gastro-oesophageal reflux disease (GORD) and has been linked to Barrett's metaplasia and cancer. Although duodenogastric reflux is a prerequisite for bile in the oesophagus, little is known about its importance in GORD.

METHODS

Some 341 patients with GORD were assessed by simultaneous 24-h gastric and oesophageal bilirubin monitoring. Definitions of increased bilirubin exposure were based on the 95th percentiles in healthy volunteers. The relationship between gastric and oesophageal bilirubin exposure and the correlation with disease severity were analysed.

RESULTS

Of the 341 patients with GORD, 130 (38.1 per cent) had increased gastric and 173 (50.7 per cent) had increased oesophageal bilirubin exposure. Of the 173 patients with bile in the oesophagus, 89 (51.4 per cent) had normal and 84 (48.6 per cent) had increased gastric bilirubin exposure. Of these 84 patients, 75 (89 per cent) had oesophagitis or Barrett's oesophagus (P = 0.003). These effects were mainly related to differences in supine reflux.

CONCLUSION

Bile in the oesophagus originates from either normal or increased gastric bilirubin exposure. Patients with increased duodenogastric reflux are more likely to have oesophagitis or Barrett's oesophagus. These findings highlight the role of duodenogastric reflux as an additional factor in the pathogenesis of GORD.

Laparoscopic Nissen repair: indications, techniques and long-term benefits

BACKGROUND

The Nissen fundoplication or total 360 degrees fundoplication is probably the most frequently used anti-reflux procedure throughout the world. With the advent of laparoscopic surgery the popularity among surgeons to perform a laparoscopic Nissen fundoplication has even increased.

AIM

The purpose of this paper is to provide an overview of the experience of laparoscopic Nissen fundoplication over the past 15 years.

METHOD

We performed an extensive review of the literature in order to ascertain the representative papers. In addition, available consensus papers, especially with regard to indication and technique, were assessed. Indication for a laparoscopic Nissen fundoplication should depend on documentation of the presence of disease as well as objective testing of the functional disorders and the complications. The technique of Nissen fundoplication is discussed controversially. Consensus exists with regard to floppiness of the wrap, necessary closure of the crurae and the use of a calibration method during the performance of the wrap.

RESULTS

The laparoscopic technique creates a learning curve, which needs to be respected. Large prospective series in recent years have shown a complication rate between 5% and 10%, depending on the definition of the complication. In these last prospective series good and excellent results have been reported, of between 85% and 95%. Reflux recurrence is reported as between 1% and 8.5%, with a concomitant dysphagia rate of 0%-10%.

CONCLUSIONS

The Nissen fundoplication is currently performed throughout the world, most frequently in a minimally invasive technique. Several randomized trials that have been performed in the past years document that the Nissen fundoplication is an effective procedure for the treatment of pathological gastro-oesophageal reflux disease when a critical indication is used for well-defined patients.

[Is duodeno-gastro-esophageal reflux just a bystander of acid reflux?]

BACKGROUND & AIM

Duodeno-gastro-esophageal reflux (DGER) as measured with bilirubin monitoring is observed in many patients with reflux disease especially in Barrett's esophagus. As acid suppression is an effective therapy of reflux disease, DGER is frequently just considered as a bystander of acid reflux. To define the importance of DGER, reflux of duodenal contents was evaluated by bilirubin monitoring in the stomach.

METHODS

100 patients with reflux disease were evaluated (62 m, 38 f, 50 (12) years). 26 patients had Barrett's esophagus, 57 had esophagitis and 17 non- erosive reflux disease (pH pos.). All patients were evaluated with simultaneous 24-hour bilirubin monitoring in the esophagus and stomach. Results were compared to 35 measurements of healthy volunteers in the esophagus and 41 measurements in the stomach.

RESULTS

Normal values: DGER - Exposure time esophagus > 11.8 % using an absorbance value > 0.14, duodenogastric reflux (DGR) - Exposure time stomach >24.8 % using an absorbance value > 0.25. 56 % of the patients had DGER, 41 % had DGR. 29 of the 41 patients with DGR had DGER (71 %), while 27 of the 56 patients with DGER had physiologic duodenogastric reflux (48 %).

DISCUSSION

About 30 % of the patients with reflux disease show DGER combined with excessive DGR. Therefore, DGER is not just a bystander of acid reflux. The excessive DGR in some patients adds additional potentially dangerous substances to the esophageal reflux.

Randomized clinical trial comparing quality of life after straight and pouch coloanal reconstruction

BACKGROUND

Functional results after rectal resection with straight coloanal anastomosis are poor. While most functional aspects are improved with coloanal J pouch anastomosis, it is still unclear whether this translates into better quality of life. The aim of this trial was to investigate health-related quality of life as a primary endpoint in patients undergoing sphincter-saving rectal resection.

METHODS

Sixty-four patients were randomized to either straight (n = 32) or coloanal J pouch (n = 32) anastomosis. Patients were studied before operation, at the time of stoma reversal and at 3-month intervals for 1 year thereafter. Quality of life was measured using two generic (Gastrointestinal Quality of Life Index and European Organization for Research and Treatment of Cancer (EORTC) QLQ-C30) and one disease-specific (EORTC QLQ-CR38) instruments. Functional results using a standardized score as well as manometric variables were recorded.

RESULTS

Thirty-nine patients (19 with a pouch and 20 with a straight anastomosis) completed the trial. There was a marked difference between the two groups with regard to quality of life profile. Patients with a pouch reconstruction had a significantly better quality of life, particularly in the early postoperative period.

CONCLUSION

Patients undergoing low anterior rectal resection and coloanal J pouch reconstruction may expect not only better functional results but also an improved quality of life in the early months after surgery compared with patients who receive a straight coloanal anastomosis.

[Reconstruction modes following gastrectomy. Results of experimental and clinical controlled trials]

Reconstruction modes following gastrectomy. Results of experimental and clinical controlled trials. In animal experiments four reconstruction methods following gastrectomy were compared: Roux-en Y reconstruction with (n = 33) and without pouch (n = 50) and isoperistaltic jejunum interposition with (n = 26) and without pouch (n = 55). The results were mostly influenced by the extent of esophagitis, documenting the reflux reduction by a pouch. Weight gain was slightly higher following jejunum interposition.Roux-en Y pouch reconstruction with jejunum interposition with pouch was compared in a randomized controlled trial. The additional operative effort of jejunum interposition did not achieve benefits in outcome. Therefore, Roux-en Y reconstruction should be advocated as standard reconstruction. The second randomized controlled trial compared Roux-en Y reconstruction with and without pouch. After more than three years, there was an advantage in life quality for patients with pouch indicating that patients with a favorable prognosis following gastrectomy should be reconstructed with a pouch.

Quality of life following laparoscopic gastric banding in patients with morbid obesity

In a prospective study of 188 patients with morbid obesity, the time-dependent changes in the quality of life of individual patients were analyzed following laparoscopic gastric banding (LGB). These 188 patients (148 females and 40 males; age 19 to 59 years; body mass index 33 to 72 kg/m(2)) underwent evaluation of the LGB according to a strict protocol that included psychological testing using standardized instruments, detailed medical evaluation, upper gastrointestinal function studies, and evaluation of quality of life using the Gastrointestinal Quality of Life Index (GIQLI). Following this evaluation, 73 patients (57 females and 16 males; age 37 years [range 19 to 59 years]; body mass index 48 kg/m(2) [range 37 to 72 kg/m(2)]) underwent LGB and were followed up for 2 years focusing on weight loss, postoperative morbidity, weight-related comorbidity, and quality of life. The results demonstrate that LGB is well able to allow for a significant loss of excess weight and a significant improvement in patients' quality of life, both after a rather short period of time after surgery and at a continuous rate throughout the follow-up. The price for this success that was found in approximately 90% of patients is a complication rate of 38%; 85% of these patients, almost one third of all patients, must undergo some type of revision surgery. However, once the complications are resolved, these patients achieve the same level of weight loss and improvement in quality of life as patients with an uncomplicated postoperative course.

How long should a long-term esophageal motility study be?

It was the aim of this study to analyze whether a shorter measuring period would render the same diagnostic information on esophageal motility as a circadian measuring period in ambulatory esophageal manometry. In an investigation on normal volunteers (n = 10), patients with gastroesophageal reflux disease without esophageal motility disorders (n = 13), and patients with esophageal motility disorders (n = 14), a comparison was performed between a 5-hr and a 24-hr motility study. An analysis was performed on inter- and intraindividual reproducibility of time periods, prandial phases, and motility sequences (Wilcoxon and Spearman test). There was no significant difference between the two analyzed measuring periods in all three groups with regard to the diagnostic information on esophageal motility in 44 of 45 comparisons for intraindividual variability. A measuring period restricted to 5 hr offers the same diagnostic information on esophageal peristaltic activity as a 24-hr motility study.

Combination of endoscopic argon plasma coagulation and antireflux surgery for treatment of Barrett's esophagus

Columnar-lined epithelium with specialized intestinal metaplasia of the esophagus (i.e., Barrett's esophagus) is a premalignant condition caused by chronic gastroesophageal reflux disease. Progression of intestinal metaplasia may be avoided by antireflux surgery, whereas regeneration of esophageal mucosa could be achieved by endoscopic argon plasma coagulation (EAPC). The aim of this prospective study was to show the early results of a combination of EAPC and antireflux surgery. Thirty patients with Barrett's esophagus were treated between August 1996 and December 1999. Regeneration of esophageal mucosa was achieved with several sessions of EAPC under general anesthesia. All patients were receiving a double dose of proton pump inhibitors. Endoscopic follow-up was performed 6 to 8 weeks after the last session. Antireflux surgery (Nissen [n = 26] or Toupet [n = 4] fundoplication) followed complete regeneration of the squamous epithelium in the esophagus. One year after laparoscopic fundoplication and EAPC follow-up with endoscopy and quadrant biopsies of the esophagus, 24-hour pH monitoring and esophageal manometry were performed. All 30 patients showed complete regeneration of the squamous epithelium after a median of two sessions (range 1 to 7) of EAPC. Twenty-two patients underwent 1-year follow-up studies. All showed endoscopically an intact fundic wrap. Recurrence of a 1 cm segment of Barrett's epithelium without dysplasia was present in two patients, both of whom had recurrent acid reflux due to failure of their antireflux procedure. Our results indicate that the combination of EAPC and antireflux surgery is an effective treatment option in patients with Barrett's esophagus with gastroesophageal reflux disease. Long-term follow-up of this therapy is necessary to evaluate its effect on cancer risk in Barrett's esophagus.

Morphologic changes of the anal sphincter musculature during and after temporary stool deviation

BACKGROUND AND AIMS

Temporary stool deviation, using a stoma, is a well-known surgical principle to protect low colorectal or coloanal anastomoses. The purpose of this study was to evaluate any morphologic changes with regard to the anal sphincter muscles during and after temporary ileostomy.

PATIENTS AND METHODS

Forty-four patients with rectal carcinomas were studied prospectively. All patients underwent low anterior resection. Reconstruction was performed using either a coloanal pouch or a straight end-to-end anastomosis. A protective stoma was fashioned in all 44 patients (ileostomy n=41; colostomy n=3). Stoma closure was carried out after a median of 85 days (41-330 days). Using a standard protocol, anal-sphincter thickness [m. puborectalis, external anal sphincter (EAS) and internal anal (IAS) sphincter] was assessed by means of endoanal ultrasonography preoperatively, at the time of stoma closure, and every 3 months thereafter for 1 year.

RESULTS

The diameter of the puborectal muscle decreased from a median preoperative value of 6.3 mm to 5.7 mm at the time of stoma closure (P=0.03). After 3 months, 6.2 mm was measured. This value remained stable for the complete follow-up period. Similar results were recorded for the EAS. The IAS thickness remained stable throughout the study period, measuring between 2.1 mm and 2.4 mm.

CONCLUSION

Temporary stool deviation does lead to morphologic changes of the anal sphincter. While the smooth muscle remains unchanged, the striated counterpart undergoes atrophic transformation. However, after passage reconstruction, i.e., stoma closure, a rapid regeneration of the voluntary muscles is observed.

Evaluation of the intestinal microflora in the rat model for esophageal adenocarcinoma

Surgically induced duodenal reflux results in cancer development in the rat esophagus. One proposed mechanism of carcinogenesis relies on the production of carcinogens in the presence of bacterial overgrowth. Against this background, intestinal microflora in the rat jejunum was analyzed before and after reflux-inducing surgery. Total gastrectomy and esophagojejunostomy were performed on Sprague-Dawley rats to produce esophageal reflux of duodenal juice (n = 12). Three days before surgery they were randomized into three groups: animals which received tap water; animals which received acidified water at pH 1.8; and animals subjected to oral decontamination with triple antibiotics. During surgery and at autopsy after 2 weeks, intestinal juice was aspirated and analyzed immediately for bacterial content. The physiologic microflora of the rat jejunum contained Lactobacillus spp. and Bacteroides spp., both of which were resistant to the antibiotic regimen. Bacterial overgrowth with fecal bacteria was found following surgery. Acidified water did not alter the intestinal microflora. Triple antibiotics eliminated Escherichia coli and Proteus spp. and reduced the concentration of Enterococcus spp. Bacterial overgrowth by bacteria of the fecal flora occurs in the rat model of esophageal adenocarcinoma with the potential to catalyze the production of carcinogens.

Duodenogastric reflux and foregut carcinogenesis: analysis of duodenal juice in a rodent model of cancer

The incidence of esophageal adenocarcinoma is increasing rapidly. In rats, surgically induced duodenoesophageal reflux is carcinogenic. One proposed mechanism of carcinogenesis is based on the reaction of physiological bile acids with nitrite to produce carcinogenic N:-nitroso amides. To test this hypothesis, duodenal juice was analyzed for endogenously formed N:-nitroso bile acids and its genotoxicity was determined. Esophagojejunostomy was performed on 15 Sprague-Dawley rats to produce duodeno-esophageal reflux. At the time of surgery and 2 and 6 weeks later, duodenal contents were aspirated and analyzed immediately. High performance liquid chromatography coupled to tandem mass spectrometry was used to detect bile acids and their nitroso derivates. Genotoxicity was assessed using a micronucleus test. The characteristic pattern of bile acid derivatives, with taurocholic acid (TCA) and glycocholic acid (GCA) as the predominant conjugates, was detected in all samples. However, even selective reaction monitoring experiments failed to demonstrate the presence of any N:-nitroso-TCA or N:-nitroso-GCA. In addition, other nitroso derivatives could not be detected in any of the samples by neutral loss experiments monitoring the loss of nitric oxide (detection limit 0.1% of the concentration of TCA). All samples were cytotoxic, but neither the preoperative nor the postoperative samples were genotoxic. Duodenal juice was cytotoxic but not genotoxic. Tumorigenesis of esophageal adenocarcinoma in the rodent model could not be linked to a specific carcinogen, especially not to nitroso bile acids. Chronic inflammation is likely to be the mechanism of carcinogenesis by duodenogastric reflux.

[Epidemiology and pathophysiology of Barrett esophagus]

The pathophysiology of Barrett's esophagus appears to be a sequential process; the squamous epithelium of the esophagus is replaced by multipotent undifferentiated cells; secondary to cellular damage in the course of gastroesophageal reflux disease these undifferentiated cells further differentiate under the ongoing influence of mucosal damage, thus forming the typical morphology of Barrett mucosa. While the prevalence of gastroesophageal reflux disease amounts to 10% to 30%, the prevalence of Barrett's esophagus is estimated to be 1% in the general population. The epidemiologic data of Barrett's esophagus gain special attention with regard to the fact that the specialized columnar epithelium with intestinal metaplasia represents the only recognized risk factor for the development of adenocarcinoma in the esophagus. Currently it is estimated that the risk of the development of an adenocarcinoma on the basis of Barrett's esophagus is about 30-50 fold higher than that in the general population.

Laparoscopic fundoplication--short- and long-term outcome

Gastroesophageal reflux disease is probably the most frequently occurring benign functional disorder in the Western industrial countries. With the increasing popularity of laparoscopic anti-reflux procedures, issues on the appropriate technique have been revitalized. The purpose of this study is to evaluate the short- and long-term outcomes of laparoscopic fundoplication and reflect on the perspective of an increasing frequency of performed operations. The data sampling is based on a literature review and a questionnaire. It can be summarized that reflux recurrence due to breakdown of the wrap or herniation of the wrap can also develop in later years after the primary surgery and amount up to 8%. Persistent dysphagia is a severe problem in the first post-operative year, but usually decreases with time and is limited to rates of 3-5% on the long-term follow-up. Other functional problems, such as gasbloat, meteorism and epigastric pain--the cause often cannot be further detected or specified--limit the quality of life of patients after laparoscopic anti-reflux surgery in the long-term follow-up in up to 5% of cases. Side effects of laparoscopic antireflux procedures can be limited to 5 to 10%, but not totally avoided.

Role of the lower esophageal sphincter and hiatal hernia in the pathogenesis of gastroesophageal reflux disease

The relative importance of the lower esophageal sphincter (LES) and hiatal hernia in the pathogenesis of gastroesophageal reflux disease is controversial. To identify the role of hiatal hernia and LES in reflux disease, 375 consecutive patients with foregut symptoms and no previous foregut surgery were evaluated. All patients underwent upper endoscopy, stationary manometry, and 24-hour esophageal pH monitoring. Hiatal hernia was diagnosed endoscopically, when the distance between the crural impression and the gastroesophageal junction was >/=2 cm. The LES was considered structurally defective when the resting pressure was </=6 mm Hg, the overall length was less than 2 cm, and/or the abdominal length was less than 1 cm. Factors predicting abnormal esophageal acid exposure (composite score >14.7) were analyzed using multivariate analysis. The presence of a hiatal hernia and a defective LES were identified as independent predictors of abnormal esophageal acid exposure. LES pressure and abdominal length were reduced in patients with hiatal hernia by 4 mm Hg and 0.4 cm, irrespective of the presence of gastroesophageal reflux disease. It is concluded that both a structurally defective LES and hiatal hernia are important factors in the pathogenesis of reflux disease. It is hypothesized that in the presence of a structurally normal LES, the altered geometry of the cardia imposed by a hiatal hernia facilitates the ability of gastric wall tension to pull open the sphincter.

Variability in the composition of physiologic duodenogastric reflux

Duodenogastric reflux has long been associated with various diseases of the foregut. Even though bile is often used as a marker, duodenogastric reflux consists of other components such as pancreatic juice and duodenal secretions. The aim of this study was to investigate the occurrence of duodenogastric reflux, its components, and the variability of its composition in normal subjects. Twenty healthy volunteers (7 men and 13 women) whose median age was 24 years underwent combined 24-hour bilirubin and gastric pH monitoring and intraluminal gastric aspiration. All probes were placed at 5 cm below the lower border of the lower esophageal sphincter. Aspiration was performed hourly and at any time when bilirubin and/or pH monitoring showed signs of duodenogastric reflux. Elastase and amylase were measured in the aspirate. All volunteers had episodes of physiologic duodenogastric reflux. A total of 70 episodes of duodenogastric reflux were registered with a median of three episodes (range 1 to 8) per subject. Most bile reflux occurred separately from pancreatic enzyme reflux. Pancreatic enzyme aspirate was significantly more often associated with a rise in pH in comparison to bile reflux (P <0.01). Duodenogastric reflux is a physiologic event with varying composition. Both bile and pancreatic enzyme reflux frequently occur separately. These findings could explain the disagreement regarding assessment and interpretation of duodenogastric reflux in the past. Thus monitoring of duodenogastric reflux requires more than the detection of just one component.

Comparison of different J-pouches vs. straight and side-to-end coloanal anastomoses: experimental study in pigs

PURPOSE

Functional results after low anterior resection with straight coloanal anastomosis are poor. Although certain functional aspects are improved with coloanal J-pouch anastomosis, evacuation difficulties are encountered in some of these patients. The aim of the study was to investigate the functional results of different reconstruction methods after low anterior resection in a standardized pig model.

METHODS

Thirty-two adult Göttinger mini pigs were randomly assigned either to straight end-to-end (Group 1), side-to-end (Group 2), small (4-cm limb length) J-pouch (Group 3), or large (8-cm limb length) J-pouch (Group 4) coloanal anastomosis after low rectal excision. The animals were investigated 12 weeks after the operation by measuring neorectal compliance and ceruletide-induced defecation. Eight pigs without operation were used as controls (Group 5).

RESULTS

Compliance was lowest in Groups 1 and 2, which were significantly different compared with both pouch designs and controls. Neorectal compliance of pigs with either small or large pouches did not differ significantly compared with one another or controls. Defecation was significantly impaired in pigs with a large pouch compared with all other groups. Pigs with side-to-end anastomoses had as rapid an evacuation as animals with straight coloanal reconstruction.

CONCLUSION

Coloanal J-pouch reconstruction adequately restores reservoir capacity after low anterior resection of the rectum. From a functional point of view, side-to-end is not superior to straight coloanal anastomosis. Compared with small pouches, a large pouch design does not lead to better neorectal compliance in the pig model, whereas pouch evacuation seems to be considerably compromised.

Loss of function of Trp53, but not Apc, leads to the development of esophageal adenocarcinoma in mice with jejunoesophageal reflux

INTRODUCTION

APC and TP53 are tumor suppressor genes known to be altered frequently in human esophageal adenocarcinoma (EAC), which arises as a complication of reflux disease. To determine the functional role of these genes in the development of EAC, we have created reflux in mice gene-targeted for either Trp53 or Apc.

METHODS

Wild-type (WT), p53-knockout (Trp53-/-), or Apc-mutated (ApcMin/+) mice were generated in our breeding colony. Total gastrectomy with esophagojejunostomy was performed at 6 weeks of age, creating jejunoesophageal reflux. Unoperated control mice were maintained under identical conditions. Mice were sacrificed at 30 weeks of age. Histology of the esophagus and jejunal anastamosis or gastroesophageal junction was reviewed by a single pathologist blinded to the genotype of the animal.

RESULTS

The esophagus was normal in all of the unoperated mice (6 ApcMin/+, 6 WT, and 6 Trp53-/-). All operated mice (6 ApcMin/+, 12 WT, and 4 Trp53-/-) had esophagitis, with squamous hyperplasia and early focal ulceration. Barrett's metaplasia was identified in 33% of the operated ApcMin/+ (2/6) and 25% of the Trp53-/- (1/4) mice, but not in the WT mice. Of 4 operated Trp53-/- mice, all developed severe dysplasia of the squamous epithelium and 2 (50%) had EAC on histology, although no gross tumors were seen. No severe dysplasia or carcinoma was identified in any of the ApcMin/+ or WT mice.

CONCLUSIONS

Loss of either Trp53 or Apc leads to the development of columnar metaplasia, whereas loss of Trp53, but not Apc, leads to development of cancer in mice with jejunoesophageal reflux.

The role of 24-hr gastric pH-monitoring in the interpretation of 24-hr gastric bile monitoring for duodenogastric reflux

BACKGROUND/AIMS

Duodenogastric reflux is a physiologic phenomenon. For a number of years, alkalinization of the acidic intragastric pH environment, as assessed by 24-hour gastric pH-monitoring, was thought to be caused by duodenogastric reflux. The recent introduction of the fotooptic Bilitec system for intraluminal bilirubin measurement has created the possibility to directly quantify a component of duodenal juice.

METHODOLOGY

In this study, 24-hour gastric pH-monitoring and 24-hour bilirubin monitoring were performed in healthy subjects. The upper limits for physiologic bile reflux are the percentage of total time of bile reflux of 28.2% and an average absorbance during a reflux episode of 0.62 (95th percentile with threshold 0.25).

RESULTS

Comparing bile with pH-monitoring (absorbance > 0.25 and/or pH > 4), an increase of bilirubin was found most frequently with constant pH (43%) or an increase of pH with constant bilirubin (37%).

CONCLUSIONS

The hypothesis was drawn that the composition of duodenogastric refluxate can vary. Bile and pancreatic juice may separately contribute to duodenogastric reflux.

[Laparoscopic anti-reflux surgery--report of experiences from Germany]

This is a report on a questionnaire in Germany reflecting the activity in antireflux surgery, both in open and laparoscopic modifications in the time period of 1990 through 1995. It serves as an overview of the acceptance of diagnostic workup, indication, applied techniques, and different antireflux procedures. In a total of 104 representative hospitals, 2,036 patients were operated during this time. Almost 80% of the hospitals provide antireflux surgery in the open technique and only 1/3 of the hospitals have experience in the laparoscopic technique. There is a total rise in antireflux surgery during the last 5 years, since the number of laparoscopic antireflux operations rises constantly with a total amount of open operations of about 250 cases per year. In open surgery the most favourite technique is the Nissen-Rossetti procedure, while in laparoscopic technique the choice for the original Nissen, the Nissen-Rossetti, or the floppy Nissen technique is divided in almost equal parts.

Gastroesophageal reflux disease and mucosal injury with emphasis on short-segment Barrett's esophagus and duodenogastroesophageal reflux

Gastroeosphageal reflux disease has been associated with long segments of Barrett's esophagus Collapse

Key Words Collapse

MESH Headings

• Adult
• Aged
• Aged, 80 and over
• Barrett Esophagus/etiology
• Barrett Esophagus/pathology
• Barrett Esophagus/physiopathology
• Bilirubin/analysis
• Cardia/pathology
• Chi-Square Distribution
• Esophagitis/etiology
• Esophagogastric Junction/physiopathology
• Esophagoscopy
• Female
• Gastroesophageal Reflux/complications
• Humans
• Hydrogen-Ion Concentration
• Intestines/pathology
• Male
• Manometry
• Metaplasia
• Middle Aged
• Statistics, Nonparametric

Collapse

Grants Collapse

Affiliation(s)

S Oberg Department of Surgery, University of Southern California School of Medicine, Los Angeles, California 90033-4612, USA
M P Ritter
P F Crookes
M Fein
R J Mason
M Gadensytätter
C G Brenner
J H Peters
T R DeMeester

Collapse

Inter- and intraindividual reproducibility of anorectal manometry

BACKGROUND

This study investigates the inter- and intraindividual variability of normal values and, thus, the reproducibility of anorectal manometry.

MATERIALS AND METHODS

Following a standardized protocol, three anorectal manometries were performed 4 h apart on 2 days of investigation, with an interval of 4 weeks, in ten healthy volunteers. Measured parameters in all 60 manometries were: sphincter length (SL), resting pressure (RP), maximum squeeze pressure (MSP), relaxation of the internal anal sphincter (RIAS), and rectal compliance (RC). Interindividual variability was expressed as standard deviation from calculated mean values and intraindividual variability was tested with Wilcoxon's test for tied samples and Spearman's rank correlation test.

RESULTS

A large interindividual variability was found for all measured parameters, except for SL, reflecting the extensive absolute range of measured values. Median intraindividual variability among the six individual measurements and between both measurement days revealed that MSP, RIAS and RC are parameters which were not reproducible in this volunteer study. A significant correlation between the results of the repetitive measurements and, thus, a good reproducibility was only found for the parameters SL and RP.

CONCLUSIONS

Anorectal manometry has only limited diagnostic value; although rather exact quantifications of individual parameters can be achieved, the impact of these measurements should be regarded rather critically, since only SL and RP appeared to be reproducible parameters.

Application of the new classification for cancer of the cardia

BACKGROUND

Cancer of the cardia is now topographically classified into three types: type I, with the tumor center in the distal esophagus treated with subtotal esophagectomy; type II, arising at the gastroesophageal junction and treated with distal esophagectomy and either proximal or total gastrectomy; and type III, subcardial cancer treated with extended total gastrectomy. Our objective was to review the new classifications and compare the outcomes in patients grouped and treated according to these classifications.

METHODS

Seventy-four patients with cancer of the cardia--15 with type I, 30 with type II, and 29 with type III cancer--underwent surgical resection at our institution between 1992 and 1997. Postoperative complications, UICC stages, and survival (Kaplan-Meier) were compared.

RESULTS

The majority of patients with type I (73%) or type II (53%) cancer had stage I or II tumors, but only 27% of patients with type III cancer had this tumor stage (P < .05). Overall 30-day mortality was 4% and morbidity was 31%. Curative resections were performed in 73% (54 of 74) of the patients with 3-year survival rates of 72% (type I), 68% (type II), and 61% (type III).

CONCLUSION

The recommended therapy for the different types of cancer of the cardia results in acceptable morbidity, mortality, and survival rates.

Treatment of advanced gastroesophageal reflux disease with Collis gastroplasty and Belsey partial fundoplication

OBJECTIVE

To examine the factors affecting outcome in patients with advanced gastroesophageal reflux disease.

DESIGN

Retrospective analysis.

SETTING

University tertiary referral center.

PATIENTS

Thirty-seven patients with advanced gastroesophageal reflux disease and no previous antireflux surgery.

INTERVENTIONS

Thirty patients underwent Collis gastroplasty for esophageal lengthening and Belsey partial fundoplication. Seven patients with esophageal stricture and global loss of esophageal body motility who underwent primary esophagectomy and reconstruction were used as a comparison group.

OUTCOME MEASURES

Symptomatic outcome in all 37 patients was assessed by questionnaire at a median of 25 months (range, 5-156 months) after surgery. In a subset of 11 patients undergoing the Collis-Belsey procedure, outcome was measured using 24-hour pH and results of motility studies.

RESULTS

The Collis-Belsey procedure was successful in relieving symptoms of gastroesophageal reflux in 21 (70%) of the 30 patients. The outcome was excellent or good in 16 (89%) of 18 patients who presented with symptoms other than dysphagia, but only in 5 (42%) of 12 patients with dysphagia (P = .01). The outcome was particularly poor if dysphagia was associated with a previously dilated esophageal stricture. Persistent or induced dysphagia was the reason for failure in all but 1 patient. Results of 24-hour esophageal pH studies were returned to normal in 8 (73%) of 11 patients undergoing postoperative evaluation. Contraction amplitudes in the distal esophagus and the prevalence of simultaneous contractions in these segments did not change after the operation. All 7 patients who underwent primary esophagectomy were classified as having an excellent or good outcome and were relieved of their reflux symptoms, including dysphagia. Six of these could eat 3 meals per day and enjoyed an unrestricted diet.

CONCLUSIONS

The outcome of the Collis-Belsey procedure in patients with advanced gastroesophageal reflux disease without dysphagia is excellent. It is less so in patients with dysphagia as a preoperative symptom. Esophagectomy can provide a good outcome in patients who have a combination of dysphagia stricture and a profound loss of esophageal motility.

Duodenoesophageal reflux induces esophageal adenocarcinoma without exogenous carcinogen

In the rat model, esophageal adenocarcinoma reproducibly develops following surgically induced duodenal reflux into the esophagus and administration of nitrosamine. In addition, decreasing gastric acid via partial or total gastrectomy increases the prevalence of adenocarcinoma in this model. We questioned whether carcinogen was necessary for cancer development in the gastrectomized model and whether esophageal acidification could reverse the effect of gastrectomy. Three groups of 26 rats each were randomized to a surgical procedure to produce one of the following reflux models: gastroduodenal reflux by esophagojejunostomy, duodenal reflux by total gastrectomy and esophagojejunostomy, or no reflux by Roux-en-Y reconstruction. In a second experiment, 42 rats were operated on to induce duodenal reflux. One week following surgery, they were randomized to receive acidified water (pH 1.8) or tap water. The animals were killed at 24 weeks of age, and the esophagus was evaluated histologically. All animals with reflux had severe esophagitis and 87% developed columnar lining of the distal esophagus. Nearly half (48%) developed adenocarcinoma at the anastomotic site 16 weeks postoperatively and without carcinogen administration. Cancer prevalence did not differ between animals with gastroduodenal or duodenal reflux but tended to be lower in animals receiving acidified water. Duodenoesophageal reflux is carcinogenic in the rat model. Exogenous carcinogen is not necessary for cancer development in gastrectomized rats.

Isolated upright gastroesophageal reflux is not a contraindication for antireflux surgery

BACKGROUND

Patients with gastroesophageal reflux disease who reflux only in the upright position are thought to have a less severe abnormality. Controversy exists over whether these patients should be considered candidates for antireflux surgery.

METHODS

A total of 224 consecutive patients with increased esophageal acid exposure on 24-hour pH monitoring were classified as having upright (n = 54), supine (n = 72), or bipositional (n = 98) reflux and were evaluated by manometry and endoscopy. Of these, 116 patients had a laparoscopic Nissen fundoplication. Their clinical outcome at a median of 12 months (range 4 to 44 months) was compared.

RESULTS

Patients with upright reflux had a lower prevalence of a structurally defective lower esophageal sphincter, fewer hiatal hernias, and less esophageal injury when compared to those with bipositional reflux (p < 0.005). Excellent (asymptomatic) or good outcome (minor symptoms not requiring acid suppression therapy) was achieved in 86% of the patients with upright reflux, 90% of those with supine reflux, and 89% of those with bipositional reflux.

CONCLUSIONS

Patients with upright reflux have less complicated, earlier disease and have results equivalent to those patients with supine and bipositional reflux after antireflux surgery.

Can the combination of symptoms and endoscopy confirm the presence of gastroesophageal reflux disease?

The aim of this study was to evaluate the accuracy of symptomatology and esophagogastroduodenoscopy (EGD) in the diagnosis of proven gastroesophageal reflux disease (GERD). We evaluated the symptoms and EGD findings of 100 consecutive patients presenting with symptoms suggestive of GERD. Patients' symptoms were scored at their first visit with a standardized symptom scoring system (grades 0-3). Grade 3 symptoms were the most severe. EGD findings were classified according to the modified Savary-Miller scale. Esophageal acid exposure was quantified using 24-hour esophageal pH monitoring; a positive composite score was considered evidence of GERD. Fifty-seven patients had positive pH scores, and 43 were negative. The combination of grade 2 or 3 heartburn and/or regurgitation with erosive esophagitis or Barrett's esophagus on EGD had a 97 per cent specificity and 64 per cent sensitivity for accurately diagnosing GERD. It is concluded that, in the presence of moderate to severe symptoms and endoscopic injury, the diagnosis of GERD can be made without further studies. However, 24-hour esophageal pH monitoring is still indicated in patients with mild typical symptoms, atypical symptoms, or when the combination of heartburn and regurgitation, regardless of their severity, occurs in the absence of severe mucosal damage.

Duodenogastric reflux potentiates the injurious effects of gastroesophageal reflux

Experimental studies have shown that the severity of esophageal mucosal injury in gastroesophageal reflux disease is related to the reflux of both gastric and duodenal juice. The purpose of this study was to determine whether duodenal juice potentiates esophageal injury in patients with reflux disease or, in fact, causes no harm allowing acid and pepsin to do the damage. A total of 148 consecutive patients who had no previous gastric or esophageal surgery underwent endoscopy and biopsy, manometry, and 24-hour esophageal pH and bilirubin monitoring. Esophageal injury was defined by the presence of erosive esophagitis, stricture, or biopsy-proved Barrett's esophagus. Exposure to duodenal juice, identified by the absorbance of bilirubin, was defined as an exposure time exceeding the ninety-fifth percentile measured in 35 volunteers. To separate the effects of gastric and duodenal juice, patients were stratified according to their acid exposure time. One hundred patients had documented acid reflux on pH monitoring, and in 63 of them it was combined with reflux of duodenal juice. Patients with combined reflux (50 of 63) were more likely to have injury than patients without combined reflux (22 of 37; P < 0.05). When the acid exposure time was greater than 10%, patients with injury (n = 40) had a greater exposure to duodenal juice (median exposure time 17.2% vs. 1.1%, P = 0.006) than patients without injury (n = 5), but there was no difference in their acid exposure (16.9% vs. 13.4%). Patients with dysplasia of Barrett's epithelium (n = 9) had a greater exposure to duodenal juice (median exposure time 30.2% vs. 7.2%, P = 0.04) compared to patients without complications (n = 25), whereas acid exposure was the same (16.4% vs. 15%). Duodenal juice adds a noxious component to the refluxed gastric juice and potentiates the injurious effects of gastric juice on the esophageal mucosa.