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Query: UMLS:C0022104 (
irritable bowel syndrome
)
8,033
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The intestinal microbiota interacts with several aspects of gastrointestinal function that may affect the expression or progression of disease. For example, a role for bacterial metabolism of bile acids and food has been linked to colorectal cancer development. Studies have also shown a potential role of the intestinal microbiota in the modulation of inflammation in the intestine and joints. Normal gut physiology is molded by the interaction between the intestinal microbiota and the host's gastrointestinal tissues, including motility, absorption and secretion, and intestinal permeability. Early studies in axenic mice demonstrated gross morphological abnormalities and gut motor dysfunction related to the absence of a normal microflora, raising the possibility that shifts in commensal bacterial populations could play a role in the development of altered motility states including functional disorders of the gut. This chapter concentrates on the experimental evidence for a role of intestinal microbiota and the potential therapeutic value of probiotics in functional diseases such as
irritable bowel syndrome
.
Best
Pract Res Clin Gastroenterol 2004 Apr
PMID:Microbial-gut interactions in health and disease. Irritable bowel syndrome. 1512 72
The past decade has witnessed a tremendous expansion of our knowledge-base of genetics of inflammatory bowel disease. To a large extent, this progress reflects the scientific innovation and impact of the human genome project, which has fueled many laboratory-based studies focusing on the molecular genetics of Crohn's disease and ulcerative colitis. The complementary strategies of genome-wide linkage scanning and candidate gene analysis uncovered a number of genetic loci associated with
IBD
susceptibility. Notably, the identification of the IBD1 and IBD5 loci is a major scientific discovery. Although many issues related to the function and expression of these genes await elucidation, there is a shared optimism that pivotal clinical applications will emerge from these investigations.
Best
Pract Res Clin Gastroenterol 2004 Jun
PMID:Genome scan analyses and positional cloning strategy in IBD: successes and limitations. 1515 26
The term 'functional gastrointestinal disorder (FGID)' is used to define several variable combinations of chronic or recurrent gastrointestinal (GI) symptoms that do not have an identified underlying pathophysiology. In the absence of any objective marker, the identification and classification of FGIDs are based on symptoms. The most widely accepted classification is based on the 'Rome diagnostic criteria,' which have classified 24 FGIDs into oesophageal, gastroduodenal, bowel, biliary, anorectal and abdominal pain subcategories. Classification into mutually exclusive categories has been useful for performing epidemiological studies in homogeneous populations, but has inevitably lead to disregarding subjects with overlapping FGIDs, or with a not sufficiently standardised symptom presentation. The epidemiology of FGID is still in its infancy, as indicated by the lack of epidemiological data for many FGIDs and the widely different incidence and prevalence rates reported for the most frequently occurring and investigated FGIDs:
irritable bowel syndrome
(
IBS
), dyspepsia, constipation and oesophageal disorders. Epidemiological studies and the definitions of the various FGIDs need to be further improved and standardised.
Best
Pract Res Clin Gastroenterol 2004 Aug
PMID:Definition and epidemiology of functional gastrointestinal disorders. 1532 3
The term 'Functional diseases' implies symptoms arising from an organ without overt pathology. However this is more apparent than real since inflammation often leaves changes in nerves and mucosal function only apparent with specialised techniques. Acute onset functional dyspepsia accounts for around 1/5 of functional dyspepsia and is characterised by early satiety, nausea, vomiting and weight loss. Impaired postcibal fundal accommodation may underlie some of these symptoms. Post infectious gastroparesis is much rarer and is associated with markedly delayed gastric emptying and antral hypomotility. Approximately 1/10 of
IBS
cases describe a post infectious onset. Post infectious
IBS
is typically of the diarrhoea-predominant type. Post inflammatory functional diseases tend to be associated with less psychological abnormalities and have a better prognosis than other functional diseases. There are isolated anecdotal reports of symptom response to anti-inflammatory treatments but larger controlled trials are needed.
Best
Pract Res Clin Gastroenterol 2004 Aug
PMID:Inflammation as a basis for functional GI disorders. 1532 5
Diagnostic activity in patients with suspected
irritable bowel syndrome
(
IBS
) should be brief and focussed, limited to investigations that are likely to exclude serious alternative diagnoses and when negative support a positive diagnosis of
IBS
. The diagnosis of
IBS
is clinical, and is robust over time, although other symptoms may add to the clinical picture and other symptoms of functional disorders are common. The most important differential diagnoses are celiac disease, colorectal carcinoma and colitis. 'Red Flag' symptoms and signs should be considered indications for full colonoscopy, which should be performed with a low threshold in patients above 50 years of age. Serologic markers are useful to exclude celiac disease, but positive tests must be confirmed with duodenal biopsies.
Best
Pract Res Clin Gastroenterol 2004 Aug
PMID:Diagnostic approach to suspected irritable bowel syndrome. 1532 11
Pathophysiology of
irritable bowel syndrome
(
IBS
) is based upon multiple factors that have been organised in a comprehensive model centred around the brain-gut axis. The brain-gut axis encompasses nerve pathways linking the enteric and the central nervous systems and contains a large proportion of afferent fibres. Functionally and anatomically, visceral nerves are divided in to two categories: the parasympathetic pathways distributing to the upper gut through the vagi and to the hindgut, through the pelvic and pudendal nerves, and the sympathetic pathways, arising form the spinal cord and distributing to the midgut via the paravertebral ganglia. Several abnormalities of gut sensori-motor function have been described in patients with
IBS
. Abnormal motility patterns have been described at the intestinal and colonic levels. Changes in colonic motility are mainly related to bowel disturbances linked to
IBS
but do not correlate with pain. More recently, visceral hypersensitivity has been recognised as a main characteristic of patients with
IBS
. It is defined by an exaggerated perception of luminal distension of various segments of the gut and related to peripheral changes in the processing of visceral sensations as well as modulation of perception by centrally acting factors including mood and stress. Viscero-visceral reflexes link the two edges of the brain-gut axis and may account for the origin of symptoms in some pathological conditions. Recent advances in the understanding of the role of myenteric plexus allowed recognition of several neurotransmitters involved at the level of both the afferent and efferent pathways. Targeting the receptors of these neurotransmitters is a promising way for development of new treatments for
IBS
.
Best
Pract Res Clin Gastroenterol 2004 Aug
PMID:Alterations of sensori-motor functions of the digestive tract in the pathophysiology of irritable bowel syndrome. 1532 12
The
irritable bowel syndrome
(
IBS
) is part of the spectrum of functional bowel disorders characterised by a diverse consortium of abdominal symptoms including abdominal pain, altered bowel function (bowel frequency and/or constipation), bloating, abdominal distension, the sensation of incomplete evacuation and the increased passage of mucus. It is not surprising therefore that no single, unifying mechanism has as yet been put forward to explain symptom production in
IBS
. The currently favoured model includes both central and end-organ components which may be combined to create an integrated hypothesis incorporating psychological factors (stress, distress, affective disorder) with end-organ dysfunction (motility disorder, visceral hypersensitivity) possibly aggravated by sub-clinical inflammation as a residuum of an intestinal infection. There is currently no universally effective therapy for
IBS
. Standard therapy generally involves a symptom-directed approach; anti-diarrhoeal agents for bowel frequency, soluble fibre or laxatives for constipation and smooth muscle relaxants and anti-spasmodics for pain. New drug development has focused predominantly on agents that modify the effects of 5-hydroxytryptamine (5-HT) in the gut, principally the 5-HT(3) receptor antagonists for painful diarrhoea predominant
IBS
and 5-HT(4) agonists for constipation predominant
IBS
. More speculative new therapeutic approaches include anti-inflammatory agents, antibiotics, probiotics, antagonists of CCK1 receptors, tachykinins and other novel neuronal receptors.
Best
Pract Res Clin Gastroenterol 2004 Aug
PMID:Treatment options in irritable bowel syndrome. 1532 13
Patients with
irritable bowel syndrome
(
IBS
) are characterized by a broad spectrum of gastrointestinal (GI) symptoms. These
IBS
-symptoms and symptoms of other functional GI disorders frequently overlap. Moreover, at least in patients with severe disease manifestations there is a remarkable psychiatric comorbidity. There is a number of abnormalities of GI functions including sensory and motor dysfunction that are believed to play a role for the manifestation of symptoms in patients with these functional gastrointestinal disorders (FGID). Family studies provide strong evidence for a clustering of FGID in families. Furthermore, twin studies clearly demonstrate an increased concordance in monocygotic compared to dicygotic twins. This points towards the role of one or more hereditary factors. Considering sensory and motor function as well as the psychiatric comorbidity, polymorphisms of adrenergic, opioidergic or serotonergic receptors as well as G-protein beta3 (GNB3) subunit gene polymorphism and polymorphisms of 5-HT transporter genes are suitable mechanisms for these abnormalities. Hence acute GI infections with a mucosal inflammation appear to trigger a cascade of events that ultimately results in the manifestation of FGID, it is reasonable to assume that functionally relevant polymorphisms of genes with immunmodulating and/or neuromodulating features (OPRM1, IL-4, IL-4R, TNFalpha) play a role. It has emerged that a number of various factors may contribute to the manifestation of functional GI disorders. The currently symptom based labels for functional GI disorders may be helpful to categorize patients and target therapy. However, various underlying pathophysiologies may cause similar symptom patterns. Thus, it is reasonable to anticipate that
IBS
will be dissected accordingly and our disease concepts will accept the
irritable bowel syndrome
as the clinical manifestation of a number of different disorders.
Best
Pract Res Clin Gastroenterol 2004
PMID:IBS: a syndrome or many diseases? 1558
Following the application of simple serological tests for the diagnosis of coeliac disease (CD) in the 1980s, it gradually became clear that the prevalence of CD in different countries in the Middle East, North Africa and India is almost the same as that in Western countries. The prevalence of CD in at-risk populations in these regions is reported to range between 3 and 20% and the prevalence in people with type 1 diabetes is approximately 3-5%. Clinical manifestations of CD vary markedly with age, the duration and the extent of disease. Clinical studies showed that presentation with non-specific symptoms or no symptoms is as common in the Middle East as it is in Europe. Wheat has been the major staple food in these regions for many centuries and it is possible that the continuous and high level of exposure to wheat proteins has induced some degree of immune tolerance, leading to milder symptoms, which are misdiagnosed as
irritable bowel syndrome
or unexplained gastrointestinal disorders. A high index of suspicion for CD should be maintained in all developing countries for patients who present with chronic diarrhoea or iron deficiency anaemia. The best method for diagnosing CD in patients with diarrhoea is the panel of coeliac serological tests followed by small-bowel biopsy. In the absence of supplies for a gluten-free diet in Middle Eastern countries, maintaining this diet represents a real challenge to both patients and clinicians.
Best
Pract Res Clin Gastroenterol 2005 Jun
PMID:Coeliac disease in developing countries: Middle East, India and North Africa. 1592 41
Chronic pelvic pain (CPP) is a common condition in women and rates of consultation for CPP in general practice are similar to those for asthma and migraine. US and UK population-based studies, together with data from UK hospital settings demonstrate a substantial impact of CPP on health-related quality of life. In this review, we will examine the current evidence on the aetiology and management of CPP, focussing on the randomised controlled trials (RCTs) that are available to date. CPP is a heterogeneous condition and causation is often unclear. There are associations with specific pathological processes but a barrier to understanding is that many studies have data that are not comparable. In the community setting, as many as 60% of women with CPP have not received a specific diagnosis and up to 20% have not undergone any investigation. The factor most commonly associated with CPP in the community is
irritable bowel syndrome
, although in a tertiary setting with laparoscopy, pathology associated with CPP in ascending order of frequency is endometriosis (33%), adhesions (24%) and 'no pathology' (35%). Current RCT evidence provides some support for the use of ultrasound scanning as an aid to counselling and reassurance, progestogen (medroxyprogesterone acetate) or goserelin for pelvic congestion and a multidisciplinary approach to assessment and treatment. Adhesiolysis is not shown to be of benefit other than in women with extensive adhesions. While studied in relation to dysmenorrhoea rather than CPP, the short term results for presacral neurectomy (PSN) and laparoscopic utero-sacral nerve ablation (LUNA) seem to be similar, although PSN has better results in the long term. Selective serotonin reuptake inhibitor (SSRI) antidepressants have not been shown to be of benefit in CPP. Most of these conclusions are based on the outcome of single randomised trials and therefore need replication.
Best
Pract Res Clin Obstet Gynaecol 2006 Oct
PMID:Chronic pelvic pain: aetiology and therapy. 1676 92
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