Subtypes of irritable bowel syndrome on Rome III criteria: a multicenter study

Background and Aim: The aim of this study was to explore the distribution and clinical characteristics of four subtypes of irritable bowel syndrome (IBS) based on Rome III criteria in Chinese. Methods: A total of 754 consecutive IBS outpatients from three tertiary hospitals in China were included. Diagnostic criteria were based on Rome II or Rome III. Results: Among 754 outpatients, 510 (67.6%) patients met the Rome II criteria, 735 (97.5%) patients met the Rome III criteria and 492 (65.3%) patients met both sets of criteria. Among 735 patients who met the Rome III criteria, 66.3% had IBS with diarrhea (IBS‐D), 14.7% had IBS with constipation (IBS‐C), 4.2% had mixed IBS (IBS‐M) and 14.8% had unsubtyped IBS (IBS‐U). Most of the IBS‐D, IBS‐C and IBS‐M patients based on the Rome III criteria matched the diarrhea‐predominant IBS, constipation‐predominant IBS and alternating IBS based on the Rome II criteria, respectively. Among IBS‐U patients, 57.0%, 33.3% and 9.7% had constipation‐predominant IBS, diarrhea‐predominant IBS and alternating IBS, respectively. For IBS‐M, the frequencies of bowel movements were stable in 48.4% patients and variable in 51.6% patients. Defecation urgency and straining were most frequent in IBS‐M and least frequent in IBS‐U patients than other subtypes. About 77.2% of IBS‐U patients had abnormal stool frequency (< 3 times/week or > 3 times/day). Conclusion: The Rome III criteria are more sensitive and practical in diagnosing IBS. IBS‐D is the most frequent subtype, which is followed by IBS‐U, IBS‐C and IBS‐M. IBS‐U is a new subtype, which warrants further studies.     

Post-infectious irritable bowel syndrome in patients with Shigella infection

BACKGROUND AND AIMS: Bacterial gastroenteritis has been known as a risk factor of irritable bowel syndrome (IBS). Several risk factors of post-infectious IBS (PI-IBS) have been documented. The aims of this study were to verify the role of bacterial gastroenteritis in the development of IBS and the risk factors for the development of PI-IBS. The clinical course of PI-IBS was also investigated. METHODS: We recruited 143 patients with shigellosis during its outbreak and 113 controls. Both groups were followed up for 12 months. Bowel symptoms were evaluated by use of questionnaires at 3, 6 and 12 months after the initial recruitment. RESULTS: Complete data were obtained from 101 patients (70.6%) and 102 healthy controls (90.3%). At 12 months, 15 patients and six controls had IBS (adjusted OR; 2.9, 95% CI; 1.1-7.9). Of the 15 patients, five had IBS symptoms consistently for 12 months, three did not have IBS symptoms initially and seven had fluctuating bowel symptoms. The duration of diarrhea was an independent risk factor of PI-IBS. CONCLUSIONS: Bacterial gastroenteritis is a risk factor of IBS and the duration of diarrhea as the index of severity of initial illness is an independent risk factor of PI-IBS. The clinical course of PI-IBS is variable over the 1 year of follow-up.     

肠易激综合征结肠粘膜超微结构的观察

目的:观察肠易激综合征(IBS)患者结肠粘膜超微结构的改变。方法:使用透射电镜观察10例IBS患者降结肠粘膜的超微结构改变,并与2例正常者进行了比较性研究。结果:发现IBS组结肠粘膜微绒毛显著稀疏及缺如,排列明显不整齐;粘液细胞显著增多,吸收细胞明显减少;细胞的质膜突发达变长,细胞间隙明显增宽;平滑小泡显著减少。结论:IBS并非都是消化道功能性疾病,可能是有肠粘膜超微结构改变的器质性疾病。     

Cross‐cultural and psychological issues in irritable bowel syndrome

Irritable bowel syndrome (IBS) is one of the most common functional gastrointestinal disorders encountered by gastroenterologists worldwide. Of all the etiological factors that had been postulated to explain the pathophysiology of IBS, cultural and psychological factors are unique and difficult to understand. Culture plays an important role in coloring the presentation of IBS, and many a times, it has a significant role in several treatment aspects too. Psychological aspects like personality profiles, family relationships, societal myths, and abuse in any form are equally important in the management perspectives of IBS. In this brief review, we had tried to specifically focus on these aspects in IBS and have explained the evidences in favor of these factors. Knowledge about various cross‐cultural aspects and psychological factors in patients with IBS is essential for taking an appropriate history and for undertaking a holistic approach for the management of the same. A collaborative team effort by psychiatrists and gastroenterologists could help in reducing the burden of this difficult to treat functional bowel disorder.     

马来酸曲美布汀治疗肠易激综合征对比研究

目的探讨马来酸曲美布汀对肠易激综合征的治疗效果。方法将诊断为肠易激综合征（IBS）的97例患者随机分成试验组（47例）和对照组（50例），试验组给予马来酸曲美布汀，对照组使用复合维生素B作为安慰剂，两组疗程均为6周，治疗期间均停用其他药物，分别于治疗前及治疗的第2、4、6周及随访8、12周末进行症状评价及评分。结果试验组治疗后积分明显下降，治疗前后比较差异有非常显著性（P〈0．01）；对照组积分下降不明显，治疗前后比较差异无显著性（P〉0．05）；治疗4周后两组间比较，试验组积分下降较对照组明显，差异有非常显著性（P〈0．01）；治疗后两组疗效比较，试验组在2周后有效率达34％，8周和12周时分别达到83％和82％，疗效明显高于对照组，差异有非常显著性（P〈0．01）。结论马来酸曲美布汀对难治性功能性消化不良具有良好的治疗作用和安全性。     

肠易激综合征的治疗进展

肠易激综合征（irritable bowel syndrome,IBS）作为消化系统疾病中较为常见的功能性胃肠病,由于发病机制未 明,临床上缺乏行之有效的治疗手段,其临床诊治一直以来是研究的热点和难点。而近年来,相关药物的研发及诊疗 策略的更新,使得IBS的诊疗得到了进一步发展。文章就目前IBS的治疗进展做一论述,以期为IBS的临床诊治提供 指导,使更多的IBS患者从中获益。     

A prospective assessment of bowel habit in irritable bowel syndrome in women: defining an alternator

BACKGROUND & AIMS: Irritable bowel syndrome (IBS) is subtyped as IBS with diarrhea (IBS-D) or IBS with constipation (IBS-C) based on Rome II guidelines. The remaining group is considered as having mixed IBS (IBS-M). There is no standard definition of an alternator (IBS-A), in which bowel habit changes over time. Our aim was to use Rome II criteria to prospectively assess change in bowel habit for more than 1 year to understand IBS-A. METHODS: Female patients (n=317) with IBS entering a National Institutes of Health treatment trial were studied at baseline with questionnaires and 2-week daily diary cards of pain and stool frequency and consistency. Studies were repeated at the end of treatment (3 months) and at four 3-month intervals for one more year. Algorithms to classify subjects into IBS-D, IBS-C, and IBS-M groups used diary card information and modified Rome II definitions. Changes in bowel habit at 3-month intervals were then assessed using these surrogate diary card measures. RESULTS: At baseline, 36% had IBS-D, 31% IBS-M, and 34% IBS-C. Except for stool frequency, there were no differences between groups. While the proportion of subjects in each subgroup remained the same over the year, most individuals (more than 75%) changed to either of the other 2 subtypes at least once. IBS-M was the least stable (50% changed out by 12 weeks). Patients were more likely to transition between IBS-M and IBS-C than between IBS-D and IBS-M. Notably, only 29% switched between the IBS-D and IBS-C subtypes over the year. CONCLUSIONS: While the proportion of subjects in each of the IBS subtypes stays the same, individuals commonly transition between subtypes, particularly between IBS-M and IBS-C. We recommend that IBS-A be defined as at least one change between IBS-D and IBS-C by Rome II criteria over a 1-year period.     

Guidelines on the irritable bowel syndrome: mechanisms and practical management

Background

IBS affects 5–11% of the population of most countries. Prevalence peaks in the third and fourth decades, with a female predominance.

Aim

To provide a guide for the assessment and management of adult patients with irritable bowel syndrome.

Methods

Members of the Clinical Services Committee of The British Society of Gastroenterology were allocated particular areas to produce review documents. Literature searching included systematic searches using electronic databases such as Pubmed, EMBASE, MEDLINE, Web of Science, and Cochrane databases and extensive personal reference databases.

Results

Patients can usefully be classified by predominant bowel habit. Few investigations are needed except when diarrhoea is a prominent feature. Alarm features may warrant further investigation. Adverse psychological features and somatisation are often present. Ascertaining the patients'' concerns and explaining symptoms in simple terms improves outcome. IBS is a heterogeneous condition with a range of treatments, each of which benefits a small proportion of patients. Treatment of associated anxiety and depression often improves bowel and other symptoms. Randomised placebo controlled trials show benefit as follows: cognitive behavioural therapy and psychodynamic interpersonal therapy improve coping; hypnotherapy benefits global symptoms in otherwise refractory patients; antispasmodics and tricyclic antidepressants improve pain; ispaghula improves pain and bowel habit; 5‐HT₃ antagonists improve global symptoms, diarrhoea, and pain but may rarely cause unexplained colitis; 5‐HT₄ agonists improve global symptoms, constipation, and bloating; selective serotonin reuptake inhibitors improve global symptoms.

Conclusions

Better ways of identifying which patients will respond to specific treatments are urgently needed.     

消炎痛灌肠治疗粘液便型肠易激综合征

目的:研究消炎痛保留灌肠治疗粘液便型肠易激综合征(IBS)的疗效。方法:采用单盲及自身对照方法,应用消炎痛保留灌肠,治疗粘液便型IBS患者41例,并与庆大霉素 氢化考的松(31例)及氢化考的松 普鲁卡因(13例)两组进行比较。结果:消炎痛治疗10d使患者便次减少(P<0.05),粘液便消失(P<0.01),肠壁水肿消失(P<0.05),充血点消失(P<0.05),腹痛缓解(P<0.05)均显著优于另两组。消炎痛治疗3周复发率明显少于另2组(P<0.01)。结论:消炎痛保留灌肠治疗粘液便型IBS具有显著和近期疗效。     

Visceral perception in irritable bowel syndrome

We wished to determine if visceral perception in the rectum and stomach is altered in patients with irritable bowel syndrome and to evaluate the effects on visceral sensation of 5-HT₃ receptor blockade. Twelve community patients with diarrhea-predominant irritable bowel syndrome and 10 healthy controls were studied in a double-blind, randomized, placebo-controlled study. Using two barostats, the stomach and rectum were distended, with pressure increments of 4 mm Hg, from 10 to 26 mm Hg; visceral perception was measured on an ordinal scale of 0–10. Personality traits were measured using standard psychological methods, and somatic pain was evaluated by immersion of the nondominant hand in cold water. The effect of 5-HT₃ antagonism was tested with a single intravenous dose of ondansetron at 0.15 mg/kg. Gastric perception was higher in irritable bowel syndrome, but rectal distension was perceived similarly in irritable bowel syndrome and controls. Pain tolerance to cold water was also similar in irritable bowel syndrome and controls. Ondansetron induced rectal relaxation and increased rectal compliance but did not significantly alter gastric compliance or visceral perception. Psychological test scores were similar in patients and controls. We conclude that in this group of psychologically normal patients with irritable bowel syndrome, who were not chronic health-care seekers, visceral perception was normal. Ondansetron did not alter gut perception in health or in irritable bowel syndrome.This work was supported in part by grants AG09440, DK32121, and RR585 from the National Institutes of Health.     

Alternation of substance P‐containing neural pathways in a rat model of irritable bowel syndrome with rectal distension

OBJECTIVE: Irritable bowel syndrome (IBS) is a common disorder in clinical practice, but the pathophysiology of IBS has not been completely elucidated yet. Experiments have revealed that the concentrations of some kinds of brain–gut peptides, such as substance P, were abnormal in the plasma and/or the intestinal mucosa. In order to explore further the possible role of substance P containing nerve fibers in the enteric nervous system and central nervous system, the expression of c‐fos, a well‐established marker of activated neural pathway, was induced to show substance P containing a neural pathway in the rat model of constipation‐predominant IBS by rectal distention. METHODS: The rat model was set up by intragastric instillation of 2.0 mL water at 0–4°C in 20 male Wistar rats for two weeks. Both the model group and the controls underwent rectal distention under deep anesthesia. Sections containing the anatomical areas of interest were obtained and processed for c‐fos protein and substance P immunohistochemistry using the strept avidin‐biotin complex (SABC) method. The staining results were analyzed semi‐quantitatively, using a computerized color image analyzer with two parameters: opacity density and immunoreactive areas. The statistical difference of the opacity density and immunoreactive areas between the two groups was analyzed by a t‐test. Correlation analysis was used to investigate the relationship between the expression of substance P and c‐fos protein of the same region in the model group. RESULTS: The opacity density of substance P immunoreactive tissues in the ileocecal junction, colon, the posterior horn of the spinal cord and the hypothalamus of the model group were all significantly higher compared with those in the control group (176.6 vs 155.5, 172.3 vs 152.0, 182.1 vs 160.2, 128.3 vs 117.9; P < 0.05, respectively). Meanwhile in the ileocecal junction, colon, the posterior horn of the spinal cord and the hypothalamus of the model group, the opacity density of c‐fos protein‐positive tissue were all significantly higher than those of the same region in the controls (120.9 vs 109.0, 101.3 vs 92.2, 125.4 vs 88.7, 115.5 vs 88.6; P < 0.05, respectively). The distribution of c‐fos protein‐positive tissue is similar to that of the substance P and the analysis shows that there is close correlation between the expression of substance P and c‐fos protein of the same region in the model group (r = 0.594–0.721, P < 0.05). CONCLUSIONS: The expression of substance P and c‐fos protein in both the enteric nervous system and the central nervous system of the constipation‐predominant IBS rat model is abnormal, which suggests that an abnormal change in substance P may be involved in the pathogenesis of IBS and the substance P‐containing neural pathway may be one of the neural pathways that play important role in the regulation of the gastrointestinal function.     

Do patients with irritable bowel syndrome in primary care really differ from outpatients with irritable bowel syndrome?

Background—Little is known about the comparabilityof outpatients with irritable bowel syndrome (IBS) and patients withIBS in primary care with regard to severity of complaints,perceived limitations, other aspects of the complaints, and sex differences.
Aims—To compare outpatients with IBS with primarycare patients with IBS.
Patients—One hundred and nine patients with IBSwere recruited from general practices in Amsterdam and 86 patients withIBS were recruited from the outpatient clinic of the Department of Internal Medicine of the University Hospital in Nijmegen.
Methods—Each patient completed a questionnaire ondemographic variables, abdominal complaints, related complaints, andattributed causes of their abdominal complaints. The scores of the twogroups were compared by univariate and multivariate analysis.
Results—The outpatient group containedsignificantly more men, reported more severe abdominal pain, morefrequent complaints, more interference with daily activities, and ahigher degree of avoidance of activities (p<0.01) than the primarycare group. When each sex was analysed separately, these differencesremained for female (p<0.01) but not for male patients. Outpatientswere more likely to attribute their complaints to somatic causes(p<0.01), whereas primary care patients were more likely to attributetheir complaints to stress (p<0.01) or their agitated way of life(p<0.05). Multivariate analysis showed that a high severity score, alarge number of additional complaints, and a low score on the stress attribution were important determinants for being in the outpatient group.
Conclusions—Female outpatients consider theircomplaints to be more serious and interfering than do patients with IBSin primary care. Male outpatients were comparable to primary carepatients with IBS. More research needs to be done into sex specificdifferences in IBS and into the factors that influence the decision torefer a patient with IBS.

     

Relationship of abdominal bloating to distention in irritable bowel syndrome and effect of bowel habit

BACKGROUND & AIMS: The relationship between the sensation of bloating, often ranked as the most bothersome symptom by patients with irritable bowel syndrome (IBS), and actual distention manifest as an increase in abdominal girth is controversial. Investigation of this problem has been hampered by the lack of a reliable ambulatory technique to measure abdominal girth. The aim of this study was to use the technique of abdominal inductance plethysmography to compare diurnal variation in girth in IBS patients and healthy volunteers, relating these changes to the sensation of bloating. METHODS: Abdominal girth was recorded for 24 hours in 20 IBS-constipation (age, 18-73 y), 20 IBS-diarrhea (age, 25-62 y) and 10 IBS-alternating (age, 21-59 y) female patients meeting Rome II criteria and 20 healthy female controls (age, 18-67 y). All subjects pursued normal daily activities, recording their symptoms of bloating and pain together with bowel habit. RESULTS: All patients with IBS, irrespective of bowel habit, reported significantly greater bloating than controls (P < .0001). Forty-eight percent of patients also showed distention beyond the 90% control range, with this being most prominent in IBS-constipation. Bloating correlated strongly only with distention in IBS-constipation (r > or = 0.48; P < or = .02). Neither bloating nor distention in IBS was related to body mass index, age, parity, or psychologic status. CONCLUSIONS: Abdominal distention is a clearly definable phenomenon in IBS that can reach 12 cm. However, it only occurs in half of patients reporting bloating, and the 2 only correlate in IBS-constipation. Bloating and distention may differ pathophysiologically and this appears to be reflected in the bowel habit subtype.