Predictors of gastroparesis in out-patients with secondary and idiopathic upper gastrointestinal symptoms

BACKGROUND

Delayed gastric emptying occurs frequently in patients with upper gastrointestinal symptoms associated with functional or organic diseases.

AIMS

To evaluate whether: (i) the prevalence of delayed gastric emptying is influenced by the presence of organic disease; (ii) demographic or clinical factors predict modestly or markedly (gastroparesis) delayed emptying.

PATIENTS

A total of 327 consecutive out-patients with upper gastrointestinal symptoms.

METHODS

Routine diagnostic work-up and evaluation of demographic factors, gastrointestinal symptom evaluation and scintigraphic gastric emptying of solids were performed.

RESULTS

Organic diseases were detected in 227/327 (65%) patients: 33% had delayed emptying and 20% gastroparesis. Female gender (OR: 2.1; 95% C.I.: 1.3-3.4). overweight (0.5; 0.3-0.9), relevant postprandial fullness (1.8; 1.1-3.2) and relevant epigastric bloating (1.8; 1.1-2.9), but not the presence of organic diseases, were associated with delayed emptying. Female gender (3.9; 1.3-11.9) and relevant postprandial fullness (4.1; 1.7-10.2) were associated with gastroparesis.

CONCLUSIONS

(i) There is a high prevalence of delayed gastric emptying and gastroparesis in out-patients with upper gastrointestinal symptoms, which is not influenced by the presence of organic disease; (ii) female gender, low body weight, relevant fullness and bloating are associated with delayed emptying; female gender and relevant postprandial fullness predict gastroparesis.

Clinical findings and anti-neuronal antibodies in coeliac disease with neurological disorders

BACKGROUND

Little is known about the clinical and immunological features of coeliac disease patients with neurological disorders. In a large series of adult coeliac disease patients, we investigated the prevalence of neurological disorders and anti-neuronal antibodies, along with the clinical course.

METHODS

Neurological symptoms were investigated in 160 consecutive patients (120 F, 40 M) with biopsy-proven coeliac disease. Anti-neuronal antibodies to central/enteric nervous systems were investigated in all neurological patients, 20 unaffected ones and 20 controls.

RESULTS

Thirteen (8%) patients had neurological disorders, including epilepsy (n = 3), attention/memory impairment (n = 3), cerebellar ataxia (n = 2), peripheral neuropathy (n = 2), multiple sclerosis (n = 1), Moyamoya disease (n = 1) and Steinert's disease (n = 1). No significant demographic or clinical differences (gastrointestinal or other gluten-related signs) were found between patients with and without neurological involvement. In all but 2 of the 13 cases, the neurological disorder preceded diagnosis ofcoeliac disease. Neurological symptoms improved or disappeared in 7 patients who started a gluten-free diet within 6 months after neurological onset, and in none of 4 patients who began later. Prevalence of central nervous system anti-neuronal antibodies was significantly higher in neurological (61%) than in other patients (5%) (P = 0.0007) or controls (0%) (P = 0.00001).

CONCLUSIONS

Coeliac disease can sometimes present in the guise of a neurological disorder, which may greatly improve when a gluten-free diet is started promptly. Therefore, the possible presence of coeliac disease needs to be carefully considered in patients with cerebellar ataxia, epilepsy, attention/memory impairment or peripheral neuropathy.

A role for inflammation in irritable bowel syndrome?

Attention has been directed to the putative role of low grade mucosal inflammation in irritable bowel syndrome (IBS) on the basis of evidence showing that some patients with IBS have an increased number of inflammatory cells in the colonic and ileal mucosa. Previous episodes of infectious enteritis, genetic factors, undiagnosed food allergies, and changes in bacterial microflora may all play a role in promoting and perpetuating this low grade inflammatory process. Human and animal studies support the concept that inflammation may perturb gastrointestinal reflexes and activate the visceral sensory system even when the inflammatory response is minimal and confined to the mucosa. Thus abnormal neuroimmune interactions may contribute to the altered gastrointestinal physiology and hypersensitivity that underlies IBS. A brief review of the human and animal studies that have focused on the putative role of intestinal inflammation and infections in the pathogenesis of IBS is given.

A meal stimulation test in the diagnosis of pancreatic endocrine tumors in multiple endocrine neoplasia type 1

The diagnostic value of the determination of the serum pancreatic polypeptide (PP) and gastrin concentrations after a standard meal for early diagnosis of patients with multiple endocrine neoplasia type 1 (MEN 1) is controversial. The aim of this study was to clarify this issue. Thirteen patients with MEN 1, seven healthy family members, and eight healthy controls were studied. Plasma PP and serum gastrin were measured before and after the ingestion of a standardized meal. The meal caused a statistically significant (p < 0.05) increase of both PP and gastrin in all three groups studied. Concerning PP, no statistically significant difference was observed between patients and controls. In family members, the values were significantly (p < 0.05) lower than in the other two groups. On the whole, no significant differences in gastrin levels were noted between patients and controls; in family members, the values were significantly (p < 0.05) lower than in patients. All patients who had abnormally high postprandial values of PP and gastrin also had abnormally high basal values of these two peptides. The determination of serum PP and gastrin levels after a meal stimulation test in patients with MEN 1 adds no information about the presence of pancreatic endocrine tumors over that provided by basal values of the two peptides.

Epidemiology, clinical features and diagnosis of gastroenteropancreatic endocrine tumours

Gastroenteropancreatic (GEP) neoplasms originate from any of the various cell types belonging to the neuroendocrine system. A general characteristic of GEP endocrine tumours is that the vast majority produce and secrete a multitude of peptide hormones and amines. Many patients with malignant metastasising tumours present clinical symptoms related to hormone hyperproduction. These include the so-called carcinoid syndrome, characterised by flushing, diarrhoea, wheezing and right heart disease, which is predominantly associated with the serotonin- and tachykinins-producing carcinoids of the midgut. Several types of syndrome associated with GEP endocrine tumors are caused by overproduction of a specific hormone. For instance, the well-known Zollinger-Ellison syndrome is gastrin-mediated. The so-called 'insulinoma syndrome' depends on excessive production of insulin and proinsulin, resulting in hypoglycemia. The 'glucagonoma syndrome' is characterised by necrolytic migratory erythema, diabetes and diarrhoea. The Verner-Morrison syndrome, which is brought about by high circulating levels of vasointestinal peptide (VIP). produces severe secretory diarrhoea. Finally the 'somatostatinoma syndrome' involves gallbladder dysfunction and gallstones, diarrhoea with or without steatorrhea, and impaired glucose tolerance. The biochemical diagnosis of endocrine digestive tumors is based on general and specific markers. The best general markers are chromogranin A (CgA) and pancreatic polypeptide (PP). Specific markers for endocrine tumors include insulin, gastrin, glucagon, vaso intestinal polypeptide (VIP), somatostatin and the primary cathabolic product of serotonin, 5-hydroxyndoleacetic acid (5-HIAA). Localisation procedures commonly applied, in the diagnosis of endocrine tumours include ultrasound (US), computed tomography (CT) and somatostatin receptor scintigraphy (SRS).

Endoscopic markers in adult coeliac disease

BACKGROUND

Various endoscopic markers have been described in coeliac disease, particularly in the second part of the duodenum, with minor attention generally being paid to the duodenal bulb.

AIMS

To evaluate, prospectively, the presence of all endoscopic markers in the bulb and the second part of the duodenum on a large series of patients submitted to endoscopy for duodenal biopsy. PATIENTS AND METHODS. A total of 367 consecutive patients, submitted to endoscopy with duodenal biopsy for various indications, were considered. Biopsies were graded as normal, with partial villous atrophy (mild, moderate, severe) or with subtotal villous atrophy. Endoscopic markers and corresponding locations evaluated were: micronodular pattern [bulb and descending duodenum], mosaic appearance (bulb and descending duodenum), scalloped folds (descending duodenum), reduced or absent folds (descending duodenum).

RESULTS

In 78 patients, a diagnosis of untreated coeliac disease was made. Endoscopic markers were seen in 73/78 patients, with only a single sign present (bulb or descending duodenum) in 12 patients. In the remaining 289 patients, normal histology and normal endoscopic findings were observed, except in two patients with reduced folds. Sensitivity, specificity, positive and negative predictive values and diagnostic accuracy regarding all endoscopic markers were 93.6%, 99.3%, 97.3%, 98.3% and 98.1%, respectively

CONCLUSIONS

This study confirms the usefulness of endoscopic markers in detecting coeliac disease, underlining the importance of evaluating also abnormalities in the bulb and endoscopic single signs; although endoscopy may not detect all cases of coeliac disease, the recognition of endoscopic markers allows the selection for biopsy of unsuspected patients submitted to endoscopy for non-specific symptoms.

Upper gastrointestinal bleeding due to duodenal metastasis from primary lung carcinoma

Metastatic dissemination of lung carcinoma may involve virtually all organs, however, symptomatic spread to the small bowel is a rare occurrence. Herein, we report a case of duodenal metastatic involvement leading to severe upper gastrointestinal bleeding in the absence of symptoms referable to the primary tumour.

Intestinal inflammation and activation of sensory nerve pathways: a functional and morphological study in the nematode infected rat

BACKGROUND

In the rat, gastric distension elicits an intensity dependent pseudoaffective bradycardia mediated via capsaicin sensitive afferent and cholinergic efferent vagal pathways. Inflammation alters visceral perception although the mediators responsible have not been identified. In the nematode infected rat, there is a substantial increase in neuronal substance P (SP) content of the gut.

AIMS

To examine the effects of inflammation on perception of a noxious visceral stimulus and on SP and neurokinin 1 (NK-1) receptor immunoreactivity (IR) in visceral afferent pathways.

METHODS

Immunohistochemistry was performed on sections from the jejunum, dorsal root ganglia (DRG), and spinal cord (T1-L1) using SP and NK-1 rabbit polyclonal antibodies. In the DRG, the number of SP-IR or NK-1-IR neurones per section was visually quantified. The pseudoaffective cardiac reflex response to gastric stimulation was compared in control and Trichinella spiralis infected rats.

RESULTS

Intestinal inflammation induced a rightward shift in the intensity dependent bradycardic response to gastric distension. This was associated with a marked increase in SP-IR not only in the gut wall but also in the DRG and dorsal horn of the spine. In contrast, NK-1-IR was not increased in the gut wall. Moreover, inflammation evoked a decrease in NK-1-IR in the dorsal horn. No NK-1-IR was identified in the DRG of either control or infected animals.

CONCLUSIONS

Intestinal inflammation modulates the capsaicin sensitive pseudoaffective autonomic response to gastric distension, increases SP-IR in afferent pathways, and downregulates dorsal horn NK-1-IR. As the pseudoaffective response is capsaicin sensitive, the rightward shift of the response is likely the consequence of the decrease in NK-1 receptors in the sensory pathways.

Review article: the pharmacological treatment of acute colonic pseudo-obstruction

Acute colonic pseudo-obstruction (Ogilvie's syndrome) can be defined as a clinical condition with symptoms, signs and radiological appearance of acute large bowel obstruction unrelated to any mechanical cause. Recent reports of the efficacy of cholinesterase inhibitors in relieving acute colonic pseudo-obstruction have fuelled interest in the pharmacological treatment of this condition. The aim of the present review is to outline current perspectives in the pharmacological treatment of patients with acute colonic pseudo-obstruction. The best documented pharmacological treatment of Ogilvie's syndrome is intravenous neostigmine (2-2.5 mg), which leads to quick decompression in a significant proportion of patients after a single infusion. However, the search for new colokinetic agents for the treatment of lower gut motor disorders has made available a number of drugs that may also be therapeutic options for Ogilvie's syndrome. Among these agents, the potential of 5-hydroxytryptamine-4 receptor agonists and motilin receptor agonists is discussed.

Review article: Helicobacter pylori, mucosal inflammation and symptom perception--new insights into an old hypothesis

The role of Helicobacter pylori and the accompanying mucosal inflammatory response in functional dyspepsia is still undefined. Human and animal studies have clearly demonstrated a link between intestinal mucosal inflammation and changes in sensory-motor function. Growing clinical and basic evidence supports the concept that a similar paradigm may occur in H. pylori-related dyspepsia. The infection may both induce gastric dysmotility and trigger neuroplastic changes in the afferent neural pathways leading to visceral hyperalgesia. A reduction of central antinociceptive control systems may also play a pathophysiological role. H. pylori eradication has provided disappointing results in terms of improvement of symptoms. This may reflect the long-term recovery of neuroplastic changes occurring in the afferent nervous system or, alternatively, the incomplete resolution of gastritis and the persistent production of inflammatory mediators by resident cells in the muscularis externa. The identification of these mechanisms may provide a better understanding of the pathophysiology of H. pylori-related dyspepsia and prompt innovative therapeutic approaches.

Tachykinin-dependent and -independent components of peristalsis in the guinea pig isolated distal colon

BACKGROUND & AIMS

In the intestine, tachykinins regulate motility by participating in neuromuscular and neuro-neuronal transmission. The aim of this study was to test the hypothesis that colonic propulsion is regulated by an interplay between tachykinergic and cholinergic transmission.

METHODS

Propulsion was elicited by intraluminal distention of a thin rubber balloon, which traveled from the oral to the anal end of guinea pig isolated distal colon segments. The overall contribution of endogenous tachykinins to colonic propulsion was examined by blocking NK1, NK2, and NK3 receptors simultaneously.

RESULTS

NK2-receptor blockade by MEN 11420 inhibited propulsion, whereas blockade of NK(1) by SR 140333 or of NK3 receptors by SR 142801 had minor effects on motility. Blockade of muscarinic or nicotinic receptors by hyoscine or hexamethonium decelerated peristalsis up to propulsion arrest. In the presence of partial muscarinic receptor blockade, the NK1-receptor antagonist SR 140333 and the NK2-receptor antagonist MEN 11420 markedly inhibited propulsion. Propulsion was also inhibited by the NK3-receptor antagonist SR 142801 in the presence of partial nicotinic receptor blockade. The simultaneous administration of the 3 tachykinin antagonists inhibited propulsion by 50%.

CONCLUSIONS

This study demonstrates the existence of an interplay between tachykinergic and cholinergic pathways during peristalsis and the importance of endogenous tachykinins acting at multiple receptor sites in the control of colonic propulsion.

Diagnostic value of plasma chromogranin A in neuroendocrine tumours

AIM

The aim of this study was to assess the value of plasma chromogranin A (CgA), a protein produced by neuroendocrine cells, in the diagnosis of neuroendocrine tumours.

METHODS

Eighty subjects with neuroendocrine tumours were studied. Thirty-four had carcinoids, 21 nonfunctioning endocrine pancreatic tumours, 17 multiple endocrine neoplasia type 1 (MEN 1) (six of these also had gastrinomas), and eight had functioning pancreatic tumours (four gastrinomas, two glucagonomas, two somatostatinomas). Twenty-eight healthy subjects were studied as controls. A fasting plasma sample was obtained from each subject, and CgA plasma levels were measured by the ELISA method using a kit (Dako A/S, Denmark).

RESULTS

In control subjects, plasma CgA values were below 5 U/l. Among the patients, 20 of the 34 with carcinoid tumours, 12 of the 21 with nonfunctioning pancreatic tumours, nine of the 17 with MEN 1 (including the six with gastrinomas), and the four gastrinomas of the eight functioning pancreatic tumours, i.e. overall, 45 of the 80 patients (56.3%) had abnormally high CgA values (22-961 U/l). Most of the patients with elevated CgA values, except nine of the 10 with gastrinomas, had multiple liver metastasis.

CONCLUSIONS

The results show that the diagnostic value of plasma CgA in neuroendocrine tumours is relatively low; it may be of some interest only in patients with advanced disease and liver metastasis. Gastrinoma seems to be an exception, because in this tumour high CgA values are generally found even in the absence of liver metastasis.

Review article: the continuing dilemma of dyspepsia

Dyspepsia drains a substantial proportion of healthcare resources in industrialized countries and an appropriate management strategy is needed. An aetiological role for Helicobacter pylori infection has been demonstrated in a number of pathological conditions associated with dyspepsia, such as peptic ulcer and gastric malignancies, but not in functional dyspepsia. Endoscopy and diagnosis-based treatment, H. pylori testing and eradication therapy, history taking and empirical therapy, are the main tools that are currently available for managing patients with upper gastrointestinal symptoms. Endoscopy identifies malignancies and organic diseases of the proximal gut and therefore provides reassurance to both doctors and patients. It should be recommended in older patients with suspicious symptoms and it has proven to be more cost-effective than empirical H2-receptor antagonists in patients with ulcer-like symptoms. Empirical eradication in all dyspeptics without suspicious symptoms is a cost-effective approach that cures the majority of peptic ulcers. Nevertheless, it does not control symptoms in the majority of patients, it may exacerbate gastro-oesophageal reflux disease, and it encourages antibiotic resistance. The realities of current clinical practice require empirical therapy in most, if not all, the dyspeptics seen by general practitioners. A detailed history taking can help to diagnose gastro-oesophageal reflux disease and to identify suspicious symptoms. Furthermore, identification of dyspepsia subgroups may provide guidance for empirical therapy. Nevertheless, even analysis of individual symptoms does not provide a sufficient diagnostic yield to differentiate functional from organic dyspepsia and appropriate investigations are needed in patients with poor response to short-term therapy or frequent relapses.

Role of antibiotic therapy on long-term germ excretion in faeces and digestive symptoms after Salmonella infection

BACKGROUND

The role of antibiotic therapy on Salmonella faecal excretion is controversial. Acute Salmonella gastroenteritis induces long-lasting digestive symptoms in up to one-third of subjects. The role of antimicrobial therapy on persistent post-infectious symptoms is unknown.

AIM

To investigate the role of antibiotic therapy on long-term germ faecal excretion and digestive symptoms after Salmonella infection.

SUBJECTS AND METHODS

1543 subjects [518 aged between 3 and 5 years (35.3%); 950 between 6 and 10 years (64.7%) and 75 adults (4.9%)] involved in a single outbreak of Salmonella enteritis fulfilled the study criteria by repeating stool cultures and answering a symptom questionnaire 3 months post-infection.

RESULTS

327 subjects (21.2%) were treated with antibiotics during the acute infection [121 children aged 3-5 years (23.4%), 175 children aged 6-10 years (18.4%) and 31 adults (41.3%)]. Antibiotic treatment did not affect Salmonella excretion at any of the time points studied up to three months post-infection in any age group as compared to age-matched untreated controls. Persistent digestive symptoms were more common among the patients treated with antibiotics (9.5% vs. 2.9%; P=0.003).

CONCLUSIONS

Antibiotic therapy does not affect Salmonella enteritis excretion. Digestive symptoms after clearance of the infectious agent are significantly higher in patients treated with antibiotics during acute gastroenteritis.

Clinical use of manometry for the diagnosis of intestinal motor abnormalities

Digestive symptoms suggestive of intestinal motor disorders, such as abdominal pain and distension, fullness, vomiting, constipation and diarrhoea, are very common and non-specific, and may be clinical manifestations of both organic and functional diseases. Both radiology and endoscopy are important in the diagnosis of structural gastrointestinal lesions that can affect motility and offer indirect signs of impaired gastrointestinal functions, but the diagnosis of gut motility disorders currently relies on the manometric assessment of contractile activities. Small bowel manometry helps to identify normal motility features and consequently to identify abnormal motor patterns. Small bowel manometry can help to differentiate mechanical obstruction from pseudo-obstruction and neurogenic from myogenic motor disorders. Manometry is an invasive technique which is not well accepted by patients and requires specific skills from investigators. Also, manometric assessment is limited to referral centres with a specific interest in the field of digestive functions, in general, and motility, in particular. Only patients who remain undiagnosed after extensive traditional work-up and fail repeated courses with medical therapy should be referred for the manometric test. Understanding the underlying pathophysiologic mechanisms of abnormal motility and developing new therapies are the goals of the current research in this fascinating field of medicine.

Idiopathic myenteric ganglionitis underlying intractable vomiting in a young adult

Inflammatory infiltration of intestinal myenteric plexuses (i.e. myenteric ganglionitis), along with severe intestinal motor abnormalities, may accompany paraneoplastic syndromes, neurological disorders and gastrointestinal infections, although rare cases can be idiopathic. In this report, we describe the case of a patient who presented with chronic intractable vomiting and weight loss associated with idiopathic myenteric ganglionitis mainly involving the stomach. Tissue analysis showed that the inflammatory infiltrate comprised T lymphocytes (CD4+ and CD8+), and peptide immunolabelling revealed a marked decrease of substance P/tachykinin immunoreactive staining in nerve fibres and myenteric neurones. Following systemic steroid therapy, the patient's symptoms dramatically improved, and after one year of follow-up his general condition remains satisfactory. The possible mechanisms leading to symptom generation and gastric dysmotility in the context of an idiopathic myenteric ganglionitis are discussed.

Standards for non-invasive methods for gastrointestinal motility: scintigraphy. A position statement from the Gruppo Italiano di Studio Motilità Apparato Digerente (GISMAD)

Scintigraphic techniques are well established methods to assess gastrointestinal transit patterns. The main advantages are represented by the possibility to evaluate, in a relatively non-invasive manner, the transit time of specific components of physiological meals as well as of some digestive secretions. These techniques are generally well accepted by the patients and results are largely not operator dependent. Their main limitation is the use of a radioisotope, that prevents repeated applications in all subjects and immediate exclusion of women of childbearing potential. Due to the high costs of these tests and the limited availability of Nuclear Medicine Departments, scintigraphic techniques should be reserved for well-selected patients. A review is made of the technical requirements and indications for scintigraphic tests currently available for clinical purposes (gastric emptying study, oesophageal transit time, evaluation of gastro-oesophageal reflux, intestinal and colonic transit time, evaluation of biliary motility and of duodenogastric reflux).

Treatment of gastroenteropancreatic neuroendocrine tumours with octreotide LAR

BACKGROUND

Octreotide long acting repeteable (LAR) is a new somatostatin analogue whose activity lasts 28 days.

AIM

To assess its therapeutic efficacy, tolerability, and safety in patients with gastroenteropancreatic neuroendocrine tumours.

METHODS

A total of 16 patients were studied; 10 patients with carcinoid tumours, three with non-functioning pancreatic tumours, two with Zollinger-Ellison syndrome associated with multiple endocrine neoplasia type 1, and one with glucagonoma were studied. Octreotide LAR was administered intramuscularly at a dose of 20 mg every 28 days for a mean of 10.7 months (range 6-15 months).

RESULTS

In carcinoid tumour patients, octreotide LAR normalized bowel movements in nine out of 10 cases, and flushing episodes disappeared in seven out of eight cases. Even in the remaining six patients the symptoms disappeared. In carcinoid tumour patients, urinary 5-hydroxyindoleacetic acid decreased significantly. In the two patients with Zollinger-Ellison syndrome/multiple endocrine neoplasma type 1 and in the patient with glucagonoma, serum gastrin and plasma glucagon, respectively, decreased considerably. Tumour size remained unchanged in 14 out of 16 patients, and increased in the remaining two. No side-effects were observed.

CONCLUSIONS

Octreotide LAR appears to have a good therapeutic efficacy, tolerability and safety in the treatment of neuroendocrine tumours. Its effects are similar to those of octreotide and lanreotide. However, because it only needs to be administered once every 28 days, it is preferable in clinical practice.

Gastric emptying and dyspeptic symptoms in patients with nonautoimmune fundic atrophic gastritis

Our aim was to evaluate the relationship between gastric emptying and demographic, clinical, histological, and secretory features in patients with nonautoimmune fundic atrophic gastritis. Only 31% of 45 patients with fundic atrophic gastritis presented with achlorhydria. Scintigraphic gastric emptying of solids was delayed compared to healthy controls. Patients with achlorhydria showed gastric emptying rates lower than those with preserved acid secretion. Significant, but weak, correlations were observed between emptying rates and both peak acid output (Rs = 0.33) and serum gastrin levels (Rs = -0.36), but not with grading of mucosal atrophy. No symptom differences were observed between patients with or without achlorhydria, but a weak correlation was detected between peak acid output and the severity of epigastric pain (Rs = 0.40). In conclusion, patients with fundic atrophic gastritis present delayed gastric emptying that is weakly related to the reduction of the acid secretion and the raising of serum gastrin levels rather than to the severity of the atrophy.

Role of nitric oxide- and vasoactive intestinal polypeptide-containing neurones in human gastric fundus strip relaxations

The morphological pattern and motor correlates of nitric oxide (NO) and vasoactive intestinal polypeptide (VIP) innervation in the human isolated gastric fundus was explored. By using the nicotinamide adenine dinucleotide phosphate hydrogen (NADPH)-diaphorase and specific rabbit polyclonal NO-synthase (NOS) and VIP antisera, NOS- and VIP-containing varicose nerve fibres were identified throughout the muscle layer or wrapping ganglion cell bodies of the myenteric plexus. NOS-immunoreactive (IR) neural cell bodies were more abundant than those positive for VIP-IR. The majority of myenteric neurones containing VIP coexpressed NADPH-diaphorase. Electrical stimulation of fundus strips caused frequency-dependent NANC relaxations. N(G)-nitro-L-arginine (L-NOARG: 300 microM) enhanced the basal tone, abolished relaxations to 0.3 - 3 Hz (5 s) and those to 1 Hz (5 min), markedly reduced ( approximately 50%) those elicited by 10 - 50 Hz, and unmasked or potentiated excitatory cholinergic responses at frequencies > or =1 Hz. L-NOARG-resistant relaxations were virtually abolished by VIP (100 nM) desensitization at all frequencies. Relaxations to graded low mechanical distension (< or =1 g) were insensitive to tetrodotoxin (TTX: 1 microM) and L-NOARG (300 microM), while those to higher distensions (2 g) were slightly inhibited by both agents to the same extent ( approximately 25%). In the human gastric fundus, NOS- and VIP immunoreactivities are colocalized in the majority of myenteric neurones. NO and VIP mediate electrically evoked relaxations: low frequency stimulation, irrespective of the duration, caused NO release only, whereas shortlasting stimulation at high frequencies induced NO and VIP release. Relaxations to graded mechanical distension were mostly due to passive viscoelastic properties, with a slight NO-mediated neurogenic component at 2 g distension. The difference between NO and VIP release suggests that in human fundus accommodation is initiated by NO. British Journal of Pharmacology (2000) 129, 12 - 20

Risk indicators of organic diseases in uninvestigated dyspepsia: a one-week survey in 246 Italian endoscopy units

OBJECTIVE

To evaluate the predictive value of demographic and clinical features and of the results of an office-based test for Helicobacter pylori antibodies, in the presence of organic dyspepsia.

DESIGN

Over a 1-week period, 2206 consecutive patients first referred for endoscopy in 246 Italian centres were included.

METHODS

Demographic and clinical features, endoscopy findings, and histological diagnosis of H. pylori infection were recorded for all patients. IgG antibodies to H. pylori were determined in 2128 cases by a rapid, immunochromatographic method (Flex Sure HP, S.K.D., San Jose, CA).

RESULTS

Endoscopic abnormalities were found in 939 patients (42.6%). Histologically assessed H. pylori infection was predictive for duodenal ulcer (odds ratio (OR), 6.79; 95% confidence interval (CI), 4.4-10.5). Being male (OR, 1.97; 95% CI, 1.7-2.3), older than 40 years (OR, 1.81; 95% CI, 1.5-2.2), a smoker (OR, 1.88; 95% CI, 1.6-2.3), and presenting nocturnal awakening (OR, 1.62; 95% CI, 1.3-2.0) were independently associated with secondary dyspepsia. Epigastric (OR, 1.50; 95% CI, 1.2-1.9) and retrosternal pain (OR, 1.39; 95% CI, 1.1 -1.8) severe enough to affect the usual activities were predictive of organic diseases. The results of the Flex Sure HP test correlated poorly with histological findings.

CONCLUSIONS

Male gender, older age, cigarette smoking, a family history of peptic ulcer, symptoms severe enough to induce awakening, epigastric/retrosternal pain severe enough to influence the usual activities are all independently (although weakly) associated with organic dyspepsia. H. pylori infection is strongly associated with duodenal ulcer, but the rapid test we used was not sensitive enough to achieve clinical utility.

Esophageal and gastric nitric oxide synthesizing innervation in primary achalasia

OBJECTIVE

We performed a qualitative and quantitative analysis of the nitrinergic neurons in the esophageal and gastric component of the lower esophageal sphincter (LES) and gastric fundus of patients with primary achalasia.

METHODS

Four muscle strips were obtained from the esophagogastric junction (two from the esophageal and two from the gastric side of the LES), and two from the gastric fundus of six patients with endstage achalasia who underwent an esophagogastric myotomy plus hemifundoplication. Control specimens were obtained from eight patients who underwent surgery for cancer of the thoracic esophagus. Fixed sections were processed for NADPH-diaphorase histochemistry and the number (mean +/- SE) of nitrinergic neurons per section was visually quantified in each specimen.

RESULTS

In the controls, nitric oxide fibers were distributed to the muscle layer and surrounding myenteric neurons of both the LES and the gastric fundus. By contrast, achalasic patients showed a marked decrease of nitric oxide nerves and labeled neurons in both esophageal and gastric components of the LES and the gastric fundus. Quantitative assessment in achalasic patients showed that the mean number of nitrinergic neurons was dramatically reduced in both the esophageal (0.2 +/- 0.1) and the gastric component (2 +/- 0.6) of the LES as compared to those in controls (15 +/- 5 and 12 +/- 4, respectively; p < 0.05); nitrinergic neurons in the gastric fundus (3 +/- 1) were significantly reduced in comparison to those of controls (10 +/- 2) (p < 0.05).

CONCLUSIONS

Our results indicate that achalasia is a motor disorder with an intrinsic inhibitory denervation of the esophageal and gastric component of the LES and of the proximal stomach, thus providing further evidence for an extraesophageal extension of the disease.

Esophageal and gastric nitric oxide synthesizing innervation in primary achalasia

OBJECTIVE

We performed a qualitative and quantitative analysis of the nitrinergic neurons in the esophageal and gastric component of the lower esophageal sphincter (LES) and gastric fundus of patients with primary achalasia.

METHODS

Four muscle strips were obtained from the esophagogastric junction (two from the esophageal and two from the gastric side of the LES), and two from the gastric fundus of six patients with endstage achalasia who underwent an esophagogastric myotomy plus hemifundoplication. Control specimens were obtained from eight patients who underwent surgery for cancer of the thoracic esophagus. Fixed sections were processed for NADPH-diaphorase histochemistry and the number (mean +/- SE) of nitrinergic neurons per section was visually quantified in each specimen.

RESULTS

In the controls, nitric oxide fibers were distributed to the muscle layer and surrounding myenteric neurons of both the LES and the gastric fundus. By contrast, achalasic patients showed a marked decrease of nitric oxide nerves and labeled neurons in both esophageal and gastric components of the LES and the gastric fundus. Quantitative assessment in achalasic patients showed that the mean number of nitrinergic neurons was dramatically reduced in both the esophageal (0.2 +/- 0.1) and the gastric component (2 +/- 0.6) of the LES as compared to those in controls (15 +/- 5 and 12 +/- 4, respectively; p < 0.05); nitrinergic neurons in the gastric fundus (3 +/- 1) were significantly reduced in comparison to those of controls (10 +/- 2) (p < 0.05).

CONCLUSIONS

Our results indicate that achalasia is a motor disorder with an intrinsic inhibitory denervation of the esophageal and gastric component of the LES and of the proximal stomach, thus providing further evidence for an extraesophageal extension of the disease.

Anti-CagA reactivity in Helicobacter pylori-negative subjects: a comparison of three different methods

Emerging evidence suggests that infection by CagA-positive Helicobacter pylori strains is related to the development of more serious gastroduodenal diseases, thus conferring to the determination of anti-CagA antibodies a relevant clinical significance in serological screenings. The detection of anti-CagA positivity in sera negative for anti-H. pylori antibodies raises the question of whether this apparently nonsense result is merely due to a false positive reaction. To address this issue, we compared three different methods for the detection of anti-CagA antibodies. In all, 272 selected sera from patients with precisely defined H. pylori status (positive or negative concordance of five tests, ie, histology by Giemsa in both antrum and corpus, rapid urease test, culture, [13C]urea breath test, IgG ELISA) were tested for anti-CagA reactivity by three different techniques (western immunoblotting, ELISA, and recombinant immunoblotting assay). In order to assess the sensibility and specificity of each tests, we considered as "true" anti-CagA positive sera those with two out of three positive results. Sera from 70% of H. pylori-positive patients and 10% from H. pylori-negative patients turned out to be "true" positives for anti-CagA antibodies. The three methods showed similar excellent results, in terms of both sensitivity and specificity, always over 93%. It is confirmed that a proportion of patients with a negative conventional serology against H. pylori possess anti-CagA antibodies in their sera. In this paper we demonstrate that it can happen even in patients without any biological signs of actual H. pylori infection. The possibility that this can be due to a false positive laboratory result is very likely ruled out by the accuracy of the three methods used. The clinical management of these patients needs further study on larger series.

Predominant symptoms identify different subgroups in functional dyspepsia

OBJECTIVE

Dyspepsia is a common syndrome that often defies diagnosis. Whether the unexplained (or "functional") dyspepsia represents a homogeneous syndrome or includes different subgroups with specific clinical features has not been clarified. The aim of this study was to investigate the relationship between symptom severity, demographic features, and gastric dysmotility in a large series of patients with functional dyspepsia.

METHODS

Severity of individual digestive symptoms, demographic features, and scintigraphic gastric emptying of solids were evaluated in 483 patients with chronic unexplained dyspepsia.

RESULTS

Two main subgroups were identified. The first was characterized by predominant epigastric pain, male gender (61%), and normal gastric emptying. The second subgroup was characterized by predominant nonpainful symptoms, female gender (60%), a high frequency of associated irritable bowel syndrome (30%), and delayed gastric emptying (42%). A third group included approximately one-third of patients who did not present with any predominant symptom, and was characterized by a high frequency of delayed gastric emptying (30%), overlapping irritable bowel syndrome (28%), and gastroesophageal reflux disease (41%).

CONCLUSIONS

Different subgroups exist among patients with functional dyspepsia seen in a referral center. They can be identified by the predominant symptom and are characterized by different demographic, clinical, and pathophysiological features.

How should Helicobacter pylori negative patients be managed?

Dyspepsia is a digestive syndrome distinct from (although frequently overlapping with) gastro-oesophageal reflux disease (GORD) and irritable bowel syndrome (IBS), which is characterised by various combinations of painful and non-painful symptoms arising from the epigastrium. Dyspepsia can be secondary to a variety of diseases, but in most instances it is idiopathic. Helicobacter pylori infection is responsible for the majority of peptic ulcers and of other diseases potentially associated with dyspepsia. Nevertheless, a causal role for H pylori infection in symptom occurrence has not been established. Experimental data indicate that H pylori eradication does not improve symptoms in the majority of dyspeptic patients. It has been proposed recently that H pylori negative patients should be managed according to their clinical presentation. Some reports suggest that taking into consideration the most relevant or "predominant" symptom may help to identify distinct subgroups among dyspeptic patients with different underlying pathophysiological abnormalities and different responses to treatment. Well designed and conducted prospective studies are needed to verify whether treatment of H pylori negative dyspeptic patients based on the predominant symptom actually is a cost effective approach.

Relevance of gastrointestinal motor disturbances in functional dyspepsia

Gastrointestinal motor abnormalities are frequent findings in patients with functional dyspepsia. However, these abnormalities are rather non-specific and seem to be restricted to a proportion of patients. Furthermore, they are not necessarily time-linked to symptom perception. The relationship of digestive motor derangements and symptoms in functional dyspepsia remains, therefore, unsettled. A variety of methodological and conceptual shortcomings characterize many of the studies investigating the relationship between gastrointestinal motility disorders and dyspeptic symptoms, and this obviously contributes to a higher level of uncertainty in the field. Recent reports suggest that gastrointestinal dysmotility is associated with perception of some dyspeptic symptoms, at least in a subset of patients. Well-conducted studies using appropriate methodology are needed to verify whether gastrointestinal motor disorders play a causal role in functional dyspepsia and whether this is of clinical relevance.

Tachykinin NK(1)receptor-mediated inhibitory responses in the guinea-pig small intestine

We used in vivo, in vitro studies and immunohistochemistry to elucidate the mechanisms activated by tachykinin NK(1)receptors in evoking inhibitory motor response in the guinea-pig small intestine. In vivo, the selective NK(1)receptor agonist GR 73,632 produced a dose-dependent suppression of the distension-induced duodenal contractions, and a decrease of basal tone. These effects were reduced by pretreatment with the NK(1)receptor antagonist SR 140,333. In L-Nomega-nitro-L-arginine methylesther hydrochloride-pretreated animals, the suppressant effect of GR 73,632 on duodenal contractions was reduced, whereas the relaxation of the basal tone was unaffected. In vitro, GR 73,632 evoked a biphasic response consisting of a transient, tetrodotoxin-sensitive inhibitory effect followed by tetrodotoxin-resistant contractions. SR 140,333 blocked both inhibitory and excitatory motor responses induced by GR 73,632. NK(1)immunoreactivity was localized to myenteric and submucosal neurons and to interstitial cells of Cajal in the deep muscular plexus of the small intestine. NK(1)receptor-expressing neurons had Dogiel type I morphology and many of them were beta-nicotinamide adenine phosphate dinucleotide-diaphorase-positive, indicating they are inhibitory neurons. In conclusion, in the guinea-pig small intestine, NK(1)receptor stimulation evokes a myogenic excitatory motor response and a neurogenic inhibitory motor response that involves, at least in part, a nitrinergic pathway.

A histological and immunohistochemical study of neuropeptide containing somatic nerves in the levator ani muscle of women with genitourinary prolapse

BACKGROUND

To evaluate the changes occurring in the somatic innervation throughout the levator ani muscle in women with genitourinary prolapse and stress urinary incontinence (SUI).

METHODS

Thirty-four patients with genital prolapse entered the study and ten subjects with non-malignant pathologies acted as a control group. All patients were evaluated by urodynamic investigation and an electromyographic study of pelvic floor muscles to define the type of urinary incontinence. Biopsy samples were obtained from both groups of patients: the site of muscle biopsies were left and right part of perirectal pubococcygeus muscle. The evaluation of immunoreactivity was semiquantitative and based on staining intensity and distribution.

RESULTS

In all cases, S-100 protein and NSE immunoreactivities were found in nerve fascicles running throughout the striated muscle. NPY and VIP positivities were more intense and diffuse, whereas SP immunoreactivity was quite scanty. The different patterns of NPY and VIP expression changed in relation to degree of genital prolapse and to the presence of SUI.

CONCLUSIONS

Our immunohistochemical study shows the presence in the pelvic floor of neurons that are able to synthesize neuropeptides. The lower immunoreactivity score of same neuropeptides (VIP, NPY) observed among patients with third degree genital prolapse and with SUI could be related to biochemical damage of the neurons with subsequent lower production of chemical messengers.

Constipation: a common problem in patients with neurological abnormalities

Constipation is a frequent complaint among patients with different neurological diseases. This review provides a brief account of the numerous conditions affecting the central, peripheral and intrinsic (enteric) nervous systems in which constipation can be the only clinical manifestation or a component of a complex syndrome. Recent neuropathophysiological acquisitions show that any structural or functional impairment of the intrinsic innervation of the gut, including both developmental (i.e., Hirschsprung's disease and intestinal neuronal dysplasia) and acquired (i.e., either degenerative or inflammatory neuropathies) disorders, can be associated with constipation. Constipation may also arise from derangements of the peripheral nervous system, including diabetes and primary chronic autonomic failure (pandysautonomias). Finally, in the central nervous system, a wide array of disorders (post-traumatic, degenerative, ischaemic or neoplastic) are recognized to determine bowel dysfunction, ultimately leading to constipation. Further understanding of the fine pathophysiological mechanisms through which the intrinsic and extrinsic nerve supplies to the digestive system are involved in idiopathic constipation or in diseases generating this symptom will hopefully lead to a better treatment of this frequent pathological condition.

Relevance of gastrointestinal motor disturbances in functional dyspepsia

Gastrointestinal motor abnormalities are frequent findings in patients with functional dyspepsia. However, these abnormalities are rather non-specific and seem to be restricted to a proportion of patients. Furthermore, they are not necessarily time-linked to symptom perception. The relationship of digestive motor derangements and symptoms in functional dyspepsia remains, therefore, unsettled. A variety of methodological and conceptual shortcomings characterize many of the studies investigating the relationship between gastrointestinal motility disorders and dyspeptic symptoms, and this obviously contributes to a higher level of uncertainty in the field. Recent reports suggest that gastrointestinal dysmotility is associated with perception of some dyspeptic symptoms, at least in a subset of patients. Well-conducted studies using appropriate methodology are needed to verify whether gastrointestinal motor disorders play a causal role in functional dyspepsia and whether this is of clinical relevance.

Evidence that tachykinins are the main NANC excitatory neurotransmitters in the guinea-pig common bile duct

Application of electrical field stimulation (EFS; trains of 10 Hz, 0.25 ms pulse width, supramaximal voltage for 60 s) to the guinea-pig isolated common bile duct pretreated with atropine (1 microM), produced a slowly-developing contraction ('on' response) followed by a quick phasic 'off' contraction ('off peak' response) and a tonic response ('off late' response), averaging 16+/-2, 73+/-3 and 20+/-4% of the maximal contraction to KCl (80 mM), n=20 each, respectively. Tetrodotoxin (1 microM; 15 min before) abolished the overall response to EFS (n 8). Neither in vitro capsaicin pretreatment (10 microM for 15 min), nor guanethidine (3 microM, 60 min before) affected the excitatory response to EFS (n 5 each), showing that neither primary sensory neurons, nor sympathetic nerves were involved. Nomega-nitro-L-arginine (L-NOARG, 100 microM, 60 min before) or naloxone (10 microM, 30 min before) significantly enhanced the 'on' response (294+/-56 and 205+/-25% increase, respectively; n=6-8, P<0.01) to EFS. The combined administration of L-NOARG and naloxone produced additive enhancing effects (655+/-90% increase of the 'on' component, n = 6, P<0.05). The tachykinin NK2 receptor-selective antagonist MEN 11420 (1 microM) almost abolished both the 'on' and 'off late' responses (P<0.01: n=5 each) to EFS, and reduced the 'off-peak' contraction by 55+/-8% (n=5, P<0.01). The subsequent administration of the tachykinin NK1 receptor-selective antagonist GR 82334 (1 microM) and of the tachykinin NK3 receptor-selective antagonist SR 142801 (30 nM), in the presence of MEN 11420 (1 microM), did not produce any further inhibition of the response to EFS (P>0.05; n=5 each). At 3 microM, GR 82334 significantly reduced (by 68+/-9%, P<0.05, n=6) the 'on' response to EFS. The contractile 'off peak' response to EFS observed in the presence of both MEN 11420 and GR 82334 (3 microM each) was abolished (P<0.01; n=6) by the administration of the P2 purinoceptor antagonist pyridoxalphosphate-6-azophenyl-2',4'-disulphonic acid (PPADS, 30 microM). PPADS (30 microM) selectively blocked (75+/-9 and 50+/-7% inhibition, n = 4 each) the contractile responses produced by 100 and 300 microM ATP. Tachykinin-containing nerve fibres were detected by using immunohistochemical techniques in all parts of the bile duct, being distributed to the muscle layer and lamina propria of mucosa. In the terminal part of the duct (ampulla) some labelled ganglion cells were observed. In conclusion, this study shows that in the guinea-pig terminal biliary tract tachykinins, released from intrinsic neuronal elements, are the main NANC excitatory neurotransmitters, which act by stimulating tachykinin NK2 (and possibly NK1) receptors. ATP is also involved as excitatory neurotransmitter. Nitric oxide and opioids act as inhibitory mediators/modulators in this preparation.

Asymptomatic glucagonoma presenting with an isolated hepatic nodule

A 37-year-old male patient, without any particular symptoms apart from moderate right upper quadrant postprandial pain, was found to have a liver mass identified as a glucagon-producing tumor. Plasma glucagon levels were slightly increased, whereas those of other gut peptides were within the normal range. Despite an extensive pre- and intraoperative diagnostic work-up, a presumed primary glucagonoma remained undetected. This unusual presentation with the absence of any symptoms typical of glucagonoma, as well as the presence of histopathological features characteristic of both benign and malignant forms of glucagonoma, make this case very peculiar. A clinically silent, apparently unrelated adenocarcinoma of the left colon was also found. The concomitant presence of a glucagonoma and a carcinoma of the large intestine has not been previously reported, and its significance remains unclear.

Detection of substance P immunoreactivity in human peripheral leukocytes

The neuropeptide substance P (SP) has a marked proinflammatory effect and modulates the immune response. In this study, we tested the hypothesis that human peripheral leukocytes contain SP. Resting peripheral leukocytes collected from healthy volunteers (n = 20) were studied by applying a SP rabbit polyclonal antiserum to both flow cytometry and immunohistochemistry. To identify possible changes in Sp expression, we also analyzed both activated T-lymphocytes (cell cultures; n = 5 normal subjects) and neoplastic hematologic samples of different types of leukemias. Flow cytometry showed that normal granulocytes and monocytes contained SP, whereas lymphocytes were generally negative (or weakly positive) with the exception of a few (10-20%) positive subsets. In comparison, activated T-lymphocytes were markedly immunolabeled by SP as well as samples from neoplastic patients demonstrated strong SP immunoreactivity in all cell lineages. This pattern was confirmed by immunohistochemistry on cytospins. Our results support a potential role for SP-mediated immunomodulatory mechanisms both in normal and pathological conditions.