The incidence of inflammatory bowel disease (IBD) has been increasing in Southeast Asia (SEA) in tandem with its economic growth and urbanization over the past 2 decades. Specific characteristics of IBD in SEA are similar to East Asia and the West, such as the declining ratio of ulcerative colitis to Crohn's disease. However, exceptionally low familial aggregation is seen. Smoking is also not a common risk factor in patients with Crohn's disease. The incidence of perianal disease is higher in SEA than in Australia and is comparable to the West. In a multiracial population, such as Singapore and Malaysia, Indians have the highest incidence and prevalence rates, which are likely to be due to important putative mutations. For instance, a higher frequency of the NOD2 predisposing mutation SNP5 and IBD risk allele IGR2198a and IGR2092a were found in Indians. Although differences in the genetic constitution play an important role in the epidemiology and prognosis of IBD in SEA, the emergence of this disease offers a unique opportunity to identify potential exposomes that contribute to its pathogenesis.

Evidence is emerging that inflammatory bowel diseases (IBDs) are becoming increasingly prevalent in developing countries, altering the previously held view that these were diseases of the West. Within this is a substantial increase in the burden of this disease in India, a matter of great importance to the country itself as well as in furthering our understanding of the disease. There is comparatively less data on this, both from the epidemiological standpoint as well as on disease pathogenesis in this particular cohort and is very much a subject matter of evolving understanding and research. This article aims to look at the changing global distribution of the disease and its implications. The Indian disease phenotype, and the aetiology of disease development will also be addressed with particular focus on differing pathogenetic processes in the Indian subpopulation, with consideration of what clues may be offered by the increasing incidence of the disease in this developing nation. Available evidence will be evaluated with the objective of providing a comprehensive overview of the development of IBD in India.

Inflammatory bowel disease (IBD), once considered to be a Western disease, is increasingly being reported from India and other Asian countries. The present review summarizes epidemiology and disease characteristics of IBD in India with reference to other Asian countries and the West.

India is projected to have one of the highest disease burden of IBD across the globe. The overall genetic risk and microbial signature in Indian IBD patients are similar to those of patients in the West as demonstrated by the similar incidence of IBD in second-generation Indian immigrants and matching perturbations in the structural and functional component of gut microbiota in Indian studies. The concept of the hygiene hypothesis continues to remain controversial with Indian studies demonstrating contradictory findings. The disease characteristics, long-term outcomes including the risk of colorectal cancer, and the effect of pregnancy on IBD and vice versa in Indian patients with IBD are in general similar with few differences. Unlike patients in the West, very few Indian patients have a positive family history.

The Indian disease pattern is going through a phase of epidemiological transition with a surge in the incidence of IBD. The epidemiology and disease characteristics of IBD mirror the patterns observed in the West.

Pseudopolyps are a well described entity in the literature and even though the exact pathogenesis of their formation is not completely understood, they are considered non-neoplastic lesions originating from the mucosa after repeated periods of inflammation and ulceration associated with excessive healing processes. Their occurrence is less common in Crohn's disease than in ulcerative colitis, and their overall prevalence ranges from 4% to 74%; moreover, they are found more often in colon but have been detected in other parts of the gastrointestinal tract as well. When their size exceeds the arbitrary point of 1.5 cm, they are classified as giant pseudopolyps. Clinical evaluation should differentiate the pseudopolyps from other polypoid lesions, such as the dysplasia-associated mass or lesion, but this situation represents an ongoing clinical challenge. Pseudopolyps can provoke complications such as bleeding or obstruction, and their management includes medical therapy, endoscopy and surgery; however, no consensus exists about the optimal treatment approach. Patients with pseudopolyps are considered at intermediate risk for colorectal cancer and regular endoscopic monitoring is recommended. Through a review of the literature, we provide here a proposed classification of the characteristics of pseudopolyps.

Inflammatory bowel disease (IBD), both ulcerative colitis (UC) and Crohn's disease (CD), once thought to be uncommon, is now seen commonly in India. The Indian Society of Gastroenterology (ISG) Task Force on IBD decided to collate data on the clinical spectrum of IBD currently prevailing in India.

An open call to members of ISG was given through publication of a proforma questionnaire in the Indian Journal of Gastroenterology and the web portal of ISG. The proforma contained questions related with demographic features, family history, risk factors, clinical manifestations and characteristics, course of disease, and pattern of treatment of IBD.

Of 1,255 filled questionnaires received, 96 were rejected and 1,159 (92.3 %) were analyzed. This comprised data on 745 (64.3 %) patients with UC, 409 (35.3 %) with CD, and 5 with indeterminate colitis. The median duration of illness was longer in patients with CD (48 months) compared to those with UC (24 months) (p = 0.002). More than one half of patients (UC 51.6 %, CD 56.9 %) had one or more extraintestinal symptoms. A definite family history of IBD was present in 2.9 % (UC 2.3 % and CD 4.6 %; p = 0.12). The extent of disease in UC was pancolitis 42.8 %, left-sided colitis 38.8 %, and proctitis alone in 18.3 %. The extent of disease involvement in CD was both small and large intestine in 39.6 %, colon alone in 31.4 % and small intestine alone in 28.9 %. Stricturing and fistulizing disease were noted in 18.8 % and 4.4 % of patients with CD respectively. Chronic continuous and intermittent disease course were present in 35.5 % and 47.2 % of UC patients respectively, and in 23.1 % and 68.8 % of CD patients. Four percent of patients with UC had undergone colectomy, while 15.2 % of patients with CD underwent surgical intervention.

The present survey provides a reasonable picture of the demographic features and clinical manifestations of Indian patients with IBD, their risk factors, course of disease, and the treatment given to them.

In 2010, the Indian Society of Gastroenterology's Task Force on Inflammatory Bowel Diseases undertook an exercise to produce consensus statements on ulcerative colitis. This consensus, produced through a modified Delphi process, reflects our current understanding of the definition, diagnostic work up, treatment and complications of ulcerative colitis. The consensus statements are intended to serve as a reference point for teaching, clinical practice, and research in India.

Inflammatory bowel disease (IBD), including both ulcerative colitis (UC) and Crohn's disease (CD), emerged and dramatically increased for about a century. Despite extensive research, its cause remains regarded as unknown. About a decade ago, a series of findings made me suspect that saccharin may be a key causative factor for IBD, through its inhibition on gut bacteria and the resultant impaired inactivation of digestive proteases and over digestion of the mucus layer and gut barrier (the Bacteria-Protease-Mucus-Barrier hypothesis). It explained many puzzles in IBD such as its emergence and temporal changes in last century. Recently I further found evidence suggesting sucralose may be also linked to IBD through a similar mechanism as saccharin and have contributed to the recent worldwide increase of IBD. This new hypothesis suggests that UC and CD are just two symptoms of the same morbidity, rather than two different diseases. They are both caused by a weakening in gut barrier and only differ in that UC is mainly due to increased infiltration of gut bacteria and the resultant recruitment of neutrophils and formation of crypt abscess, while CD is mainly due to increased infiltration of antigens and particles from gut lumen and the resultant recruitment of macrophages and formation of granulomas. It explained the delayed appearance but accelerated increase of CD over UC and many other phenomena. This paper aims to provide a detailed description of a unified hypothesis regarding the etiology of IBD, including the cause and mechanism of IBD, as well as the relationship between UC and CD.

Inflammatory bowel disease is an emerging problem in Asia including India. Clinical data on this disease from eastern India and on its temporal trends in India is scarce.

Existing Indian data on inflammatory bowel disease were retrieved using PubMed and a comparison of earlier data (up to 1980s) was made with more recent data (1990s and later) and our own data to find any significant differences. Our data included clinical data of 40 and ten consecutive patients with ulcerative colitis and Crohn's disease, respectively, collected prospectively from January 2003 to June 2009. For those whose symptoms started before 2003, data collection was partly retrospective. It included demography, symptoms and duration at presentation, follow-up findings, course, extraintestinal manifestations, treatment outcome and complications. Data were analysed by descriptive and analytical statistics.

Sixty-five percent of our ulcerative colitis patients presented with pancolitis, majority had severe clinical, endoscopic and histologic disease commensurate with other recent studies but in contrast to milder presentation in earlier studies. Of our patients, 27.5% developed pseudopolyposis of colon, two within 1 year of disease onset; 10% developed cancer colon for whom disease duration of 10 years or more was the only significant risk factor. Majority of our patients with Crohn's disease had mild inflammatory disease involving small gut which was controlled with aminosalicylates. Obscure lower GI bleed was an important mode of presentation.

Ulcerative colitis is presenting with increasing severity and extent in recent times. Rapid development of colonic pseudopolyposis was observed.

The risk for colorectal cancer (CRC) in ulcerative colitis (UC) in India is not known.

Retrospective cohort from a tertiary level hospital in South India. Analysis of archived records of all patients with UC who underwent colonoscopy and segmental biopsies over the last 25 years. Incidence densities and risk of developing high grade dysplasia or CRC was calculated and chi-squared test was performed for risk factors of interest.

Complete records were available for 532 patients, 336 (63.2%) male. The mean (+/- SEM) duration of illness was 6.04 +/- 0.29 years. In total, 234 patients (44%) had pancolitis, 121 (22.7%) had left-sided colitis and 177 (33.3%) had proctitis or proctosigmoiditis. Overall, five (0.94%) patients developed carcinoma and one (0.19%) patient had high grade dysplasia. The incidence density and risk of developing either CRC or high grade dysplasia was zero in the first 10 years of disease. In those with disease duration of 10-20 years, incidence density was 2.34 per 1000 person years' duration (PYD) for all patients with colitis and 4.5 per 1000 PYD for patients with pancolitis alone. This corresponded to risks of 2.3% and 4.4%, respectively. For those with disease duration longer than 20 years, incidence density was 2.73 per 1000 PYD for all patients and 4.9 per 1000 PYD for patients with pancolitis. This corresponded to risks of 5.8% and 10.2%, respectively. Duration of disease beyond 10 years and extent of colitis were the only risk factors significantly associated with CRC.

The risk of developing CRC is Indian patients with UC is lower than that reported from the West. Strategies for cancer surveillance in Indian patients with UC need to be tailored accordingly.

Current incidence figures on ulcerative colitis and Crohn's disease--presented in a recent multicenter study in Europe--are given, and differences in the frequency and clinical appearances of the two conditions are discussed. Trends in the frequency and clinical appearance of inflammatory bowel disease during the twentieth century are summarized, as well as the differences over time and from place to place. Correlations between age, sex, localization of disease and clinical symptoms are given. Risk of progression to more extensive disease in patients with proctitis is shown. Incidences of inflammatory bowel disease in childhood and among migrated ethnic groups are discussed. Survival and cancer risk among patients with ulcerative colitis and Crohn's disease are shown from long-term clinical epidemiological studies of well-defined patient groups. Trends in these important prognostic parameters over time are shown, as well as factors influencing prognosis of the diseases.

Ulcerative colitis occurs worldwide. It is considered common in most of Europe and North America and uncommon in most of the developing Asian countries. The incidence/prevalence of ulcerative colitis varies not only according to geographical region but also with race and ethnicity. There are no reported data from India on the incidence of the disease and its prevalence.

A house to house survey was conducted by questionnaire, formulated to enquire about symptoms that are suggestive of ulcerative colitis. Those with prolonged diarrhoea with or without rectal bleeding were considered as suspected cases. These suspected cases were subjected to video sigmoidoscopy/colonoscopy and rectal biopsy. In addition, patients already diagnosed and receiving treatment for ulcerative colitis, encountered during the survey, were reviewed. Resurvey of the same areas was conducted after a one year interval to detect new cases. Using direct methods, standardised rates were calculated using world standard population weights 22, 18, 16, 12, 12, 9, 7, 3, and 1 for each 10 year age group. Standardised rates were also obtained separately for males, females, and combined populations, using the Punjab state 1991 population census data. Rates were also estimated according to UK 2000 population data. Ninety five per cent confidence intervals (95% CI) of prevalence and incidence rates of ulcerative colitis were estimated under the assumption that the distribution of cases followed a Poisson probability model.

A total population of 51 910 were screened from January to March 1999. We identified 147 suspected cases and of these 23 were finally established as ulcerative colitis cases, giving a crude prevalence rate of 44.3 per 100 000 inhabitants (95% CI 29.4-66.6). A second visit to the same areas after one year identified 10 suspected cases in a population of 49 834. Of these, three were confirmed as "definite" ulcerative colitis giving a crude incidence rate of 6.02 cases per 100 000 inhabitants (95% CI 1.2-17.6).

This is the first population based study from India reporting on the incidence and prevalence of ulcerative colitis. The disease frequency is not much less than that reported from Europe and North America.

Ulcerative colitis occurs worldwide. It is considered common in most of Europe and North America and uncommon in most of the developing Asian countries. The incidence/prevalence of ulcerative colitis varies not only according to geographical region but also with race and ethnicity. There are no reported data from India on the incidence of the disease and its prevalence.

A house to house survey was conducted by questionnaire, formulated to enquire about symptoms that are suggestive of ulcerative colitis. Those with prolonged diarrhoea with or without rectal bleeding were considered as suspected cases. These suspected cases were subjected to video sigmoidoscopy/colonoscopy and rectal biopsy. In addition, patients already diagnosed and receiving treatment for ulcerative colitis, encountered during the survey, were reviewed. Resurvey of the same areas was conducted after a one year interval to detect new cases. Using direct methods, standardised rates were calculated using world standard population weights 22, 18, 16, 12, 12, 9, 7, 3, and 1 for each 10 year age group. Standardised rates were also obtained separately for males, females, and combined populations, using the Punjab state 1991 population census data. Rates were also estimated according to UK 2000 population data. Ninety five per cent confidence intervals (95% CI) of prevalence and incidence rates of ulcerative colitis were estimated under the assumption that the distribution of cases followed a Poisson probability model.

A total population of 51 910 were screened from January to March 1999. We identified 147 suspected cases and of these 23 were finally established as ulcerative colitis cases, giving a crude prevalence rate of 44.3 per 100 000 inhabitants (95% CI 29.4-66.6). A second visit to the same areas after one year identified 10 suspected cases in a population of 49 834. Of these, three were confirmed as "definite" ulcerative colitis giving a crude incidence rate of 6.02 cases per 100 000 inhabitants (95% CI 1.2-17.6).

This is the first population based study from India reporting on the incidence and prevalence of ulcerative colitis. The disease frequency is not much less than that reported from Europe and North America.

Ulcerative colitis (UC) is rare in Asia. Singapore is an ethnically heterogeneous city-state with a population made up of Chinese (77%), Indians (7.5%), and Malays (14%). This study describes and compares the characteristics of Chinese, Malay, and Indian patients with UC.

Retrospective chart review was performed of 235 patients seen in the largest tertiary care hospital in Singapore between 1971 and June 2000.

There were 169 (72%) Chinese, 24 (10%) Malays, and 42 (18%) Indians with UC. Male-to-female ratio was 1.8:1 (150:85). Most patients in all three races presented between the ages of 20 and 39 years. No bimodal peak in the age at presentation was seen. The median period from onset of symptoms to diagnosis was 1 month in all three races. More Malay (57%) and Indian (55%) patients had colitis extending proximal to splenic flexure at presentation compared with Chinese (32%) patients (p = 0.04). There were more Indian patients (29%) with severe disease at onset compared with Chinese (12%) and Malay (22%) patients (p = 0.035). Thirty-one percent of patients had only one episode of colitis, 12% were steroid dependent, and 4% were steroid refractory. Proctocolectomy was needed in 31 (18.3%) Chinese, 3 (12.5%) Malay, and 4 (9.5%) Indian patients. Extraintestinal manifestations were found in 6% of the Chinese, 12% of Malay patients, and 14% of Indian patients. The most common extraintestinal manifestation was arthritis, present in 6.4% of patients.

There were more Indians with UC than expected in this population. Whereas Indian and Malay patients have more extensive and severe disease at presentation than Chinese patients, this does not predict for more refractory disease or a greater need for surgery.

Studies of Asians in Asia show relatively low incidence rates for ulcerative colitis and Crohn's disease compared with North America and Europe. The prevalence of ulcerative colitis in migrant South Asians in Europe is similar to Europeans, whereas the prevalence of Crohn's disease for migrant South Asians in Europe is decreased compared with Europeans. The prevalence for both ulcerative colitis and Crohn's disease in Japan and Korea is relatively low. There are no obvious differences in age or sex distribution or rates of familial aggregation, and there are no significant differences in the clinical characteristics and natural history of ulcerative colitis and Crohn's disease in Asians compared with other racial groups with inflammatory bowel disease.

Controversy surrounds the risk of colorectal cancer (CRC) in ulcerative colitis (UC). Many studies have investigated this risk and reported widely varying rates.

A literature search using Medline with the explosion of references identified 194 studies. Of these, 116 met our inclusion criteria from which the number of patients and cancers detected could be extracted. Overall pooled estimates, with 95% confidence intervals (CI), of cancer prevalence and incidence were obtained using a random effects model on either the log odds or log incidence scale, as appropriate.

The overall prevalence of CRC in any UC patient, based on 116 studies, was estimated to be 3.7% (95% CI 3.2-4.2%). Of the 116 studies, 41 reported colitis duration. From these the overall incidence rate was 3/1000 person years duration (pyd), (95% CI 2/1000 to 4/1000). The overall incidence rate for any child was 6/1000 pyd (95% CI 3/1000 to 13/1000). Of the 41 studies, 19 reported results stratified into 10 year intervals of disease duration. For the first 10 years the incidence rate was 2/1000 pyd (95% CI 1/1000 to 2/1000), for the second decade the incidence rate was estimated to be 7/1000 pyd (95% CI 4/1000 to 12/1000), and in the third decade the incidence rate was 12/1000 pyd (95% CI 7/1000 to 19/1000). These incidence rates corresponded to cumulative probabilities of 2% by 10 years, 8% by 20 years, and 18% by 30 years. The worldwide cancer incidence rates varied geographically, being 5/1000 pyd in the USA, 4/1000 pyd in the UK, and 2/1000 pyd in Scandinavia and other countries. Over time the cancer risk has increased since 1955 but this finding was not significant (p=0.8).

Using new meta-analysis techniques we determined the risk of CRC in UC by decade of disease and defined the risk in pancolitics and children. We found a non-significant increase in risk over time and estimated how risk varies with geography.

Controversy surrounds the risk of colorectal cancer (CRC) in ulcerative colitis (UC). Many studies have investigated this risk and reported widely varying rates.

A literature search using Medline with the explosion of references identified 194 studies. Of these, 116 met our inclusion criteria from which the number of patients and cancers detected could be extracted. Overall pooled estimates, with 95% confidence intervals (CI), of cancer prevalence and incidence were obtained using a random effects model on either the log odds or log incidence scale, as appropriate.

The overall prevalence of CRC in any UC patient, based on 116 studies, was estimated to be 3.7% (95% CI 3.2-4.2%). Of the 116 studies, 41 reported colitis duration. From these the overall incidence rate was 3/1000 person years duration (pyd), (95% CI 2/1000 to 4/1000). The overall incidence rate for any child was 6/1000 pyd (95% CI 3/1000 to 13/1000). Of the 41 studies, 19 reported results stratified into 10 year intervals of disease duration. For the first 10 years the incidence rate was 2/1000 pyd (95% CI 1/1000 to 2/1000), for the second decade the incidence rate was estimated to be 7/1000 pyd (95% CI 4/1000 to 12/1000), and in the third decade the incidence rate was 12/1000 pyd (95% CI 7/1000 to 19/1000). These incidence rates corresponded to cumulative probabilities of 2% by 10 years, 8% by 20 years, and 18% by 30 years. The worldwide cancer incidence rates varied geographically, being 5/1000 pyd in the USA, 4/1000 pyd in the UK, and 2/1000 pyd in Scandinavia and other countries. Over time the cancer risk has increased since 1955 but this finding was not significant (p=0.8).

Using new meta-analysis techniques we determined the risk of CRC in UC by decade of disease and defined the risk in pancolitics and children. We found a non-significant increase in risk over time and estimated how risk varies with geography.

The aim of this study was to determine the prevalence rates of inflammatory bowel disease in the different races in Singapore.

The patients studied consisted of 58 people with an established diagnosis of ulcerative colitis (UC) and Crohn's disease (CD) as determined by a combination of clinical, radiological, endoscopic and histological criteria. The patients were residents of a well-defined geographical area in the northern part of Singapore and had been referred to the single regional hospital. Epidemiological data including sex, age, ethnicity, family history and disease type and extent were collected from case records and patient interviews.

There were 37 UC and 21 CD patients. Of the patients with UC, 67.5% were Chinese, 13.5% were Malay and 19% were Indian. The CD group consisted of 81% Chinese, 9.5% Malay and 9.5% Indian patients. The study population from which the patients were drawn was approximately 0.5 million in size.

The overall prevalence of UC was 6 per 100,000 and of CD was 3.6 per 100,000 in Singapore. There were disproportionately more Indians suffering from UC, with a prevalence of 16.2 per 100,000 in comparison with six per 100,000 for Chinese and seven per 100 000 for Malays. The relative risk of UC in Indians is 2.9-fold greater than for the Chinese (CI= 1.25-6.7) which was statistically significant. This trend was not seen for CD.

Our aim was to measure prospectively the incidence of ulcerative colitis in Leicester City and to compare this with a previous retrospective study in the same area. We also sought to compare the incidence and disease extent in the European community with that of the South Asian community and to compare the disease extent between first- and second-generation South Asian migrants.

A 3-yr prospective study of ulcerative colitis in the city of Leicester took place from October 1, 1991 to September 30, 1994 and included all cases resident in Leicester City and diagnosed as having ulcerative colitis, regardless of the extent and severity of the disease.

Extensive colitis was commoner in second-generation migrants than in the first generation (chi2 = 4.3, p = 0.04) and was comparable to the European community. The annual average incidence of ulcerative colitis was 9.1/10(5) population/yr (95% confidence interval [CI] 7.1-11.3), which is similar to the previous retrospective study. However, the annual average incidence of ulcerative colitis in the European population was 7.0/10(5) population/yr (95% CI 5-9.5), whereas that of the South Asian population was 17.2/10(5) population/yr (95% CI 11.8-24.3), confirming that the risk of ulcerative colitis in this particular community is exceptionally high.

These early results suggest that the disease pattern follows that of the indigenous population after only one generation and requires monitoring over the next decade. The incidence of ulcerative colitis in the South Asian population is high and continuing to rise.

Chronic diarrhea is a common clinical problem. To determine the possible causes in North India, we studied prospectively 71 patients with chronic diarrhea of the large bowel type. A definite diagnosis could be established in 70 patients. Ulcerative colitis was found in 18 patients, colorectal malignancies in three, colonic polyps in three, and irritable bowel syndrome in 32. In addition, seven patients with seronegative polyarthritis and chronic diarrhea were found to have chronic inflammation of the colon on histology. Two patients had pseudodiarrhea, and no diagnosis could be established in one patient. The remaining five patients with chronic diarrhea showed histologic evidence of chronic colonic inflammation with predominantly mononuclear cell infiltration of the lamina propria and increased intraepithelial lymphocytes, but results of their radiologic and endoscopic studies were normal. These five patients were classified as having microscopic (lymphocytic) colitis. We conclude that the causes of chronic diarrhea in North India patients are similar to a large extent to those seen in Western populations. Microscopic (lymphocytic) colitis is a definite clinicopathologic entity that should be considered in the differential diagnosis of chronic diarrhea.

Inflammatory bowel diseases are uncommon in the Chinese, but the incidence is rising. Their differentiation from infective colitis is often not clear-cut and diagnosing inflammatory bowel diseases can be difficult in Asia. We have studied Chinese patients with ulcerative colitis (N = 19) and Crohn's disease (N = 12) for anti-neutrophil cytoplasmic antibodies (ANCA) by indirect immunofluorescence (IIF) and enzyme-linked immunosorbent assays (ELISA). Patients with enteric fever (N = 29) and irritable bowel syndrome (N = 24) were recruited as controls. Seventy-three percent of ulcerative colitis patients exhibited either p-ANCA (31%) or c-ANCA (42%) by IIF. Twenty-five percent of Crohn's disease patients were found to be p-ANCA positive. However, these ANCA were nonreactive to anti-alpha granule, antiproteinase 3, antimyeloperoxidase, or antilactoferrin. All positive patients had extensive colitis. Sera collected from patients suffering from enteric fever and irritable bowel syndrome were negative for ANCA by IIF and ELISA. We concluded that the detection of ANCA is helpful in diagnosing inflammatory bowel diseases. Further attempts to characterize these autoantibodies are needed.

Crohn's disease and ulcerative colitis are important disorders in childhood which may present in a similar way to adult life, but the major paediatric dimension is impairment of growth and development which may occur in both disorders. Whilst the diagnosis of ulcerative colitis is usually quite quick by virtue of the pressing nature of the chief symptoms, bloody diarrhoea, the diagnosis of Crohn's disease may be significantly delayed in children as the symptoms are frequently less obvious and may not, at first, be gastrointestinal. Modern diagnosis is based upon a combination of endoscopy and radiology. Of particular importance is endoscopic biopsy which enables a definite histological diagnosis to be made. Early referral to diagnostic centres is particularly important in childhood.

A retrospective epidemiological study of ulcerative colitis (UC) and proctitis was performed in Leicestershire from 1972-89. Potential cases were identified from hospital departments of pathology, endoscopy, and medical records and from general practitioners. The county population includes more than 93,000 South Asians. There were 573 cases of UC and 286 of proctitis in Europeans and 115 cases of UC and 29 of proctitis in South Asians. The standardised incidence of UC in Europeans and South Asians was stable, except in Sikhs in whom it had increased rapidly. The relative risk of UC to South Asians was 2.45. The standardised incidences of UC in South Asians during the 1980s were: 10.8/10(5)/year in Hindus (95% confidence interval (CI) 7.4-14.1 cases/10(5)/year) 16.5/10(5)/year in Sikhs (95% CI 7.9-25.2 cases/10(5)/year), and 6.2/10(5)/year in Muslims (95% CI 1.6-10.9 cases/10(5)/year). There was no difference in incidence between Asians from East Africa and India. The standardised incidence of UC in Europeans was 5.3/10(5)/year (95% CI 4.3-6.3 cases/10(5)/year). The standardised incidences of proctitis were 3.1/10(5)/year (95% CI 1.9-2.5 cases/10(5)/year) in South Asians and 2.3/10(5)/year (95% CI 1.8-2.4 cases/10(5)/year) in Europeans. Ethnic groups had a similar disease distribution, except Sikhs in whom it was less extensive. Despite the similar disease distribution, South Asians had fewer operations and complications from UC than Europeans. There was a bimodal age specific incidence in Europeans, but not in other ethnic groups. First and second generation South Asians were at similar risk. Hindus and Sikhs have a significantly higher incidence of UC than Europeans in Leicestershire.

Experience of 189 patients with non-specific ulcerative colitis has been reviewed. The majority of patients was in the 21-30 year age group, and neither sex predominated. Seventy-two percent had mild to moderate disease. The disease was mainly confined to the left colon (60%) and 13% had total colitis.

Forty-four Asian immigrants in Birmingham and 44 age- and sex-matched white Caucasians with ulcerative colitis were compared to investigate the existence of any ethnic differences in the pattern of disease. Asian immigrants demonstrated a male preponderance of 2:1, and compared to the matched Caucasians there was a higher incidence of presenting eosinophilia and a milder course of disease, with more patients experiencing only a single initial attack. In spite of this clinical difference, total or subtotal colitis was the commonest pathological type in both white Caucasians and Indians, whereas in Pakistanis localized distal disease predominated. All ethnic groups suffered the same overall complication rate (55%) which is at variance with the experience of low complication rates in India. The age of onset of ulcerative colitis was related to age at immigration with a mean interval of 11 years. Although in some respects Asian immigrants share the disease pattern of the indigenous population, the observed significant differences could be of importance with regard to pathogenesis.

The experience with inflammatory bowel disease in a stable, defined population in northeast England is described. In this population, the incidence of inflammatory bowel disease was higher than expected. In particular, a high incidence of colorectal and anal Crohn's disease was found. The literature is reviewed in order to identify some of the factors responsible for this unusual prevalence of inflammatory bowel disease in the study population. No explanation for our unexpected findings can be advanced.

Inflammatory bowel disease is generally assumed to be rare among negroes and Indians. Over 10 years 34 cases of ulcerative colitis and 14 cases of Crohn's disease were seen in one medical and one surgical unit in Port-of-Spain, Trinidad. Twenty-six patients were Negroes, 18 were Indians, three were of mixed race, and one was Caucasian. In many of these patients the disease was extensive and several of those with Crohn's disease suffered severe complications. The assumption that inflammatory bowel disease is rare among West Indians of African and Indian origin therefore seems to be wrong.

A series of observer variation studies in a small group of patients suffering from severe acute ulcerative colitis is reported. Seventy-two separate assessments of the patients' physical signs and clinical progress were made by three independent observers.The results of this investigation suggest that there is difficulty in eliciting general physical signs such as anaemia or dehydration in these patients. By contrast, local abdominal signs such as tenderness and distension were relatively reliably elicited. The results also suggest that there are considerable problems in evaluating these clinical signs in terms of the patient's immediate subsequent progress.