Papers by Stephen Attwood
Surgery, 1994
The nonparenchymal cells (NPCs) of the liver have a strong cytotoxic activity. Our hypothesis is ... more The nonparenchymal cells (NPCs) of the liver have a strong cytotoxic activity. Our hypothesis is that their activity, which prevents metastases to the liver, may be impaired after operation. First, Sprague-Dawley rats underwent either a sham operation consisting of only a laparotomy (group L, n = 10), a laparotomy and resection of a portion of the small intestine (group R, n = 10) or no operation (group C, n = 10). After 2 days liver NPCs were isolated and divided into two fractions, large and small NPCs. The cytotoxicity of the liver NPCs and of the circulating blood mononuclear cells (BMC) was assessed. Second, we measured the growth of tumor metastases 14 days after the inoculation of a cell line (MRMT-1) into the portal vein of rats undergoing similar surgical stress (group Rm, n = 10 and group Lm, n = 10). The natural killer cell activity (anti-YAC-1) of large NPCs was 38% in group R, which was significantly less (p < 0.002) than that in groups L (72%) and C (83%). Small NPC...
Surgery, 1989
Barrett's esophagus is a common finding in patients with gastroesophageal reflux and is assoc... more Barrett's esophagus is a common finding in patients with gastroesophageal reflux and is associated with a high incidence of serious complications (stricture, ulceration, and carcinoma). The reason that only a portion of patients with reflux develop Barrett's esophagus and why some are prone to develop complications is unknown. Twenty-three patients with Barrett's esophagus underwent endoscopy, 24-hour esophageal pH monitoring, and manometry. Nine of these patients with gastritis underwent 24-hour gastric pH monitoring, and three with symptoms of duodenogastric reflux underwent 99mTc-labeled hepato-iminodiacetic acid scanning. Patients with complicated (n = 12) and uncomplicated (n = 11) Barrett's esophagus were compared with each other and with patients with reflux esophagitis (n = 53) and normal volunteers (n = 50). Patients with Barrett's esophagus showed an increased exposure to acid and alkaline gastric juice compared with patients with esophagitis and normal...
Annals of surgery, 1990
Seventy-six patients with Barrett's esophagus were cared for during a 10-year period. Fifty-s... more Seventy-six patients with Barrett's esophagus were cared for during a 10-year period. Fifty-six patients (74%) presented with complications of the disease. There were 20 strictures, 7 giant ulcers, 11 cases of dysplasia, and 29 patients with carcinoma. In patients with benign disease, 93% had mechanically defective sphincters and 83% had peristaltic failure of the lower esophageal body. Esophageal pH monitoring showed excessive esophageal exposure to pH less than 4 in 93% and excessive exposure to pH more than 7 in 34% of the patients tested. Ninety-three per cent of patients with excessive alkaline exposure had complications, compared to only 44% with normal alkaline exposure (p less than 0.01). Gastric pH monitoring, serum gastrin levels, and gastric acid analysis supported a duodenal source for the alkaline exposure. Antireflux surgery was performed using Nissen fundoplication in 30, Belsey partial fundoplication in 3, and Collis-Belsey gastroplasty in 2. Six required resecti...
Clinical Investigation, 2012
World Journal of Gastroenterology, 2012
The natural history of Barrett's esophagus is difficult to quantify because, by definition, it sh... more The natural history of Barrett's esophagus is difficult to quantify because, by definition, it should describe the course of the condition if left untreated. Pragmatically, we assume that patients with Barrett's esophagus will receive symptomatic treatment with acid suppression, usually a proton pump inhibitor, to treat their heartburn. This paper describes the development of complications of stricture, ulcer, dysplasia and adenocarcinoma from this standpoint. Controversies over the definition of Barrett's esophagus and its implications in clinical practice are presented. The presence of intestinal metaplasia and its relevance to cancer risk is discussed, and the need to measure the extent of the Barrett's epithelium (long and short segments) using the Prague guidelines is emphasized. Guidelines and international consensus over the diagnosis and management of Barrett's esophagus are being regularly updated. The need for expert consensus is important due to the lack of randomized trials in this area. After searching the literature, we have tried to collate the important studies regarding progression of Barrett's to dysplasia and adenocarcinoma. No therapeutic studies yet reported show a clear reduction in the development of cancer in Barrett' s esophagus. The effect of pharmacological and surgical intervention on the natural history of Barrett's is a subject of ongoing research, including the Barrett's Oesophagus Surveillance Study and the Aspect trial (aspirin and esomeprazole cancer chemoprevention) with interesting results. The geographical variation and the wide range of outcomes highlight the difficulty of providing an individualized risk profile to patients with Barrett's esophagus. �uture studies on the interaction of genome wide abnormalities in Barrett's and their interaction with environmental factors may allow individualization of the risk of cancer developing in Barrett's esophagus.
Parasites & Vectors, 2012
Background: The snail Neotricula aperta transmits Mekong schistosomiasis in southern Laos and Cam... more Background: The snail Neotricula aperta transmits Mekong schistosomiasis in southern Laos and Cambodia, with about 1.5 million people at risk of infection. Plans are under consideration for at least 12 hydroelectric power dams on the lower Mekong river and much controversy surrounds predictions of their environmental impacts. Unfortunately, there are almost no ecological data (such as long term population trend studies) available for N. aperta which could be used in impact assessment. Predictions currently assume that the impacts will be the same as those observed in Africa (i.e., a worsening of the schistosomiasis problem); however, marked ecological differences between the snails involved suggest that region specific models are required. The present study was performed as an initial step in providing data, which could be useful in the planning of water resource development in the Mekong. Snail population density records were analyzed for populations close to, and far downstream of, the Nam Theun 2 (NT2) project in Laos in order to detect any changes that might be attributable to impoundment.
International Journal of Clinical Practice, 2008
Eosinophilic oesophagitis (EO) is an increasingly recognised chronic, relapsing inflammatory cond... more Eosinophilic oesophagitis (EO) is an increasingly recognised chronic, relapsing inflammatory condition of the oesophagus. There has been a mini-epidemic of EO in the last decade. The incidence of this condition is higher in children and is commoner in males. There is either a family or personal history of atopic conditions present in a significant number of patients and can also be familial in up to 10%. The classical symptom in an adult is chronic, intermittent solid-food dysphagia and food impaction, often necessitating emergency endoscopic removal. Despite the history of dysphagia for a number of years, patients remain well with no weight loss, which can mislead clinicians to diagnose a functional problem with a resulting delay in the diagnosis. There are various endoscopic features of EO; commonly multiple rings and linear furrows, though these can be subtle and the mucosa may be macroscopically normal. The hallmark of this condition is the histological presence of &gt; or =15 eosinophils/high power field (HPF) in the oesophageal mucosa. Therapeutic options include avoidance of dietary allergens, topical or systemic steroids, Montelukast, Mepolizumab (anti-IL-5 antibody) and endoscopic dilation of strictures unresponsive to medical therapy.
International Journal of Clinical Practice, 2008
Gynecological Surgery, 2007
We present a case of a young black African woman who presented with recurrent haemorrhagic ascite... more We present a case of a young black African woman who presented with recurrent haemorrhagic ascites secondary to endometriosis. This is a rare entity which can be easily confused with bowel or ovarian malignancy and the few reported cases have been managed by laparotomy unlike our case which was managed purely with laparoscopic surgery.
Gastroenterology, 1998
The role of Laparoscopy in Colon and Rectal disease has been criticized by many since its incepti... more The role of Laparoscopy in Colon and Rectal disease has been criticized by many since its inception in 1990 but has become a great tool for others. Much debate has been forthcoming in the case of laparoscopic management of cancer of the colon, especially with mid and low rectal carcinoma. Evaluation of the safety and advisability of these procedures is the purpose of this study. Since 1990 thrn December 1997 we have performed 345 cases of Laparoscopic colon resection for cancer, 93 of these were tumors located in the mid and low rectum and required a LOW Anterior Resection. 88 were completed successfully with a conversion rate of 3.3% and a success rate of 96.7%. Very early in our experience a strict set of guidelines of oncological principles to dissect and extract the specimen was followed. In all cases the anastomosis has been carried out totally intracorporeally (97.8%) extracting the specimen through the rectum protected in a plastic bag in 90% of the cases. Anal dysfunction was present after transanal retrieval in 10% of the cases but was resolved within a month. Occasionally with tumors >5 cms in diameter the specimen was extracted transabdominally in a plastic bag. Lateral margins of all specimens were evaluated and compared to an open group of patients and felt to be equivalent or better. The average level of these tumors was at 11 cms. from the anal verge with a range of 4 to 15 cms. The average follow up in this group of patients is 31 months. The overall complication rate was 25% (17% Minor, 8% major complications). There was an anastomosis stricture rate of 3.2% and the leak rate was 1%. We have had no trocar site implants to date. Laparoscopic Low Anterior Resection for cancer is a feasible, safe and effective procedure in our hands, with an overall complication rate and anastomotic leak and stricture problems comparably or better to standard techniques. The advantages of Minimally Invasive procedure benefits the patient with faster recuperation, less pain and essentially a non existing wound infection rate.
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Papers by Stephen Attwood