Effect of an enteric-release formulation of naloxone on intestinal transit in volunteers taking codeine.

INTRODUCTION: Constipation is a common side-effect of opioid therapy; in addition to their analgesic effect, opioids reduce intestinal secretion and motility with an increase in whole-gut transit time. Naloxone, a specific opioid antagonist, reverses these effects but may also cause symptoms of opioid withdrawal in patients on long-term therapy. AIM: To use an enteric-release formulation, designed to produce a topical effect in the gut, with minimum systemic effects. METHODS: Naloxone 10 mg b.d. and codeine 30 mg b.d. were used with identical placebo capsules in four sets of studies; 12 male volunteers were given the drugs alone and in combination, with a control study involving double placebo, during each of four study periods. Whole-gut transit time was calculated and compared for each treatment period. RESULTS: Naloxone, both alone and with codeine, significantly shortened the mean whole-gut transit time compared with the control period, respectively, from 53.1 to 42.1 h (P=0.005) and to 40.7 h (P=0.024). Urgency to defecate was reported by two volunteers on naloxone alone and by three on combination therapy. CONCLUSIONS: The results show that the naloxone formulation counteracts the effect of codeine on intestinal transit, suggesting that it may have useful clinical applications.

Naloxone treatment for irritable bowel syndrome--a randomized controlled trial with an oral formulation.

BACKGROUND: Opioids change gut motility and secretion, causing delayed intestinal transit and constipation. Endorphins play a role in the constipation troubling some patients with irritable bowel syndrome; hence naloxone, an opioid antagonist, may have a therapeutic role. AIM: To assess the efficacy and safety of an oral formulation of naloxone in irritable bowel syndrome patients with constipation. METHODS: A randomized, double-blind, placebo-controlled trial was performed. Patients fulfilling the Rome II criteria for irritable bowel syndrome (constipation-predominant and alternating types) were randomized to receive 8 weeks of treatment with naloxone capsules, 10 mg twice daily, or identical placebo. RESULTS: Twenty-eight patients entered the study, which was completed by 25. 'Adequate symptomatic relief' was recorded in six of 14 on naloxone and three of 11 on placebo. Whilst the differences were not significant, improvements in severity gradings and mean symptom scores for pain, bloating, straining and urgency to defecate were greater with naloxone than placebo for all parameters. In addition, quality of life assessments improved to a greater extent in patients taking naloxone. CONCLUSIONS: Preliminary results suggest that naloxone is well tolerated and beneficial in patients with irritable bowel syndrome and constipation. A larger clinical trial is needed to provide sufficient statistical power to assess efficacy.

Enteric-release glyceryl trinitrate in active Crohn's disease: a randomized, double-blind, placebo-controlled trial.

BACKGROUND: Mucosal ischaemia may contribute to the pathogenesis of Crohn's disease. Microvascular abnormalities have been found in colonic resection specimens, and mucosal levels of constitutive nitric oxide synthase are reduced. AIM: To assess the efficacy of a novel, enteric-release formulation of the nitric oxide donor, glyceryl trinitrate, aimed at increasing the mucosal circulation and relaxing smooth muscle in the affected bowel. METHODS: The trial was randomized, double-blind and placebo-controlled. Baseline disease activity was assessed by a structured symptom diary, with blood tests and a quality of life assessment. Patients with a Crohn's disease activity index of > or = 150 and < 450 were randomized to receive 12 weeks of either glyceryl trinitrate (initially 6 mg twice daily, increasing to 9 mg twice daily after 6 weeks) or an identical placebo. Assessments were repeated at 6 and 12 weeks. RESULTS: Seventy patients (22 male) entered the study; 34 were given glyceryl trinitrate and 36 placebo. At 12 weeks, there were no differences between the treatment groups in terms of Crohn's disease activity index, pain, stool frequency, inflammatory markers or quality of life scores. CONCLUSIONS: Enteric-release glyceryl trinitrate did not benefit patients with mild to moderately active Crohn's disease. Whilst ischaemia may contribute to the pathogenesis of Crohn's disease, our results fail to provide supportive evidence for this hypothesis.

Incidence and presentation of coeliac disease in South Glamorgan.

OBJECTIVE: To determine the incidence and presenting features of coeliac disease and dermatitis herpetiformis in the population of South Glamorgan between 1981 and 1995. DESIGN: Retrospective case-finding study using pathology, dietetic and clinical records, data from hospital activity analysis, general practice records and a Coeliac Society questionnaire. Incidence rates were calculated using the Registrar General's mid-year estimates. SETTING: Regional hospitals, South Glamorgan, Wales. PARTICIPANTS: All new cases of coeliac disease or dermatitis herpetiformis. MAIN OUTCOME MEASURES: Crude incidence rates (per quinquennia) for both children and adults. Age, sex, family history, symptoms at the time of diagnosis and time to diagnosis from symptom onset. RESULTS: In total, 137 cases of coeliac disease (27 children, 110 adults) and 19 cases of dermatitis herpetiformis were detected. In adults with coeliac disease, incidence rates have risen from 1.32 to 3.08 per 100,000 with a 3:1 female predominance. Almost 50% of adults were over fifty years old when diagnosed and 25% had no abdominal symptoms. In children, the disease incidence has remained stable but with a rising trend in mean age at diagnosis and higher likelihood of atypical symptoms in older children. There has been no change in the incidence of dermatitis herpetiformis. Only 8.3% of all patients had an affected first-degree relative. CONCLUSIONS: In contrast to other reports of declining incidence, coeliac disease in children has remained constant in South Glamorgan, but has markedly increased in adults, particularly women. Presentation may be at any age, often with atypical symptoms, which may delay diagnosis.

Case report: Squamous carcinoma in an oesophageal foregut cyst.

Cysts within the oesophageal wall may represent inclusion cysts, retention cysts or developmental cysts. Foregut duplications are developmental anomalies, which occur as a result of abnormal canalization of the foregut during intrauterine life. Malignant transformation is an extremely rare event occurring within oesophageal cysts, adenocarcinoma being the most common histology. We report a case of squamous cell carcinoma arising within an oesophageal cyst affecting the upper third of the oesophagus. The malignant cyst was not amenable to primary surgical resection and hence was treated using chemo-radiotherapy. The treatment gave good disease control, at the expense of a high oesophageal stricture. Chemo-radiotherapy is an alternative treatment modality to achieve long-term disease control in squamous cell carcinoma complicating oesophageal foregut cyst when primary surgical resection is not possible.

A prospective study of the causes of notably raised aspartate aminotransferase of liver origin.

BACKGROUND AND AIMS: To ascertain the causes of raised aspartate aminotransferase (AST) presumed to be of hepatic origin in two hospitals and the local community served by a centralised biochemistry laboratory. METHODS: From June 1996 to February 1997 all patients with AST greater than 400 U/l were identified by the biochemistry laboratory; the patients' clinical records were studied to determine the diagnosis, the clinical outcome, and whether the raised AST and its significance had been noted. RESULTS: A total of 137 patients with a hepatic cause for the raised AST were found. The cause of the raised AST was hepatic ischaemia/hypoxia in 68, pancreatobiliary disease in 33, primary hepatocellular disease in 23, hepatic malignancy in five, and hepatic haematoma in one. In seven patients the diagnosis was unclear. The overall mortality was high (22%) with the highest mortality in the hepatic ischaemia group (37%). The recording and interpretation of the causes of raised AST was poor with only 48% having the correct diagnosis. In 38% the raised AST was apparently not noticed by the attending clinicians. CONCLUSIONS: The commonest cause of a hepatitis like biochemical picture was hepatic hypoxia (50%) followed by pancreatobiliary disease (24%). Drug induced hepatic necrosis (8.8%) was uncommon and viral hepatitis was rare (3.6%). AST concentrations returned towards normal most rapidly in patients with hepatic hypoxia and calculous biliary obstruction. Hepatitis, viral or otherwise, is an uncommon cause of a typical hepatitic biochemical result in this community.

Non-hepatic hyperammonaemia: an important, potentially reversible cause of encephalopathy.

The clinical syndrome of encephalopathy is most often encountered in the context of decompensated liver disease and the diagnosis is usually clear cut. Non-hepatic causes of encephalopathy are rarer and tend to present to a wide range of medical specialties with variable and episodic symptoms. Delay can result in the development of potentially life threatening complications, such as seizures and coma. Early recognition is vital. A history of similar episodes or clinical risk factors and early assessment of blood ammonia levels help establish the diagnosis. In addition to adequate supportive care, investigation of the underlying cause of the hyperammonaemia is essential and its reversal, where possible, will often result in complete recovery. Detection of an unborn error of metabolism should lead to the initiation of appropriate maintenance therapy and genetic counselling.