Incidence of ulcerative colitis and Crohn's disease in Danish children: Still rising or levelling out?

Global Epidemiology and Geographic Variations of Pediatric-Onset Inflammatory Bowel Disease: A Comprehensive Analysis of the Global Burden of Disease Study 1990 to 2019

BACKGROUND

An increasing incidence of pediatric-onset inflammatory bowel disease (PIBD) has been reported in many countries. However, the global burden and distribution of this disease remain less understood. We aimed to examine the global epidemiology and trends of PIBD from 1990 to 2019.

METHODS

Data from the 2019 Global Burden of Disease Study, covering 204 countries, were analyzed. We assessed key measures like incidence, prevalence, mortality, and disability-adjusted life years (DALYs) using linear regression to calculate annual percentage changes and assess trends.

RESULTS

Between 1990 and 2019, the PIBD incidence rate increased and the DALY rate and mortality rate declined. The incidence rate was notably elevated in the high Socio-demographic Index (SDI) quintile, reaching 6.3 per 100 000 person-years, corresponding to 13 914 new cases in 2019. Incidence and prevalence of PIBD positively correlated with the SDI, while higher death and DALY burdens were observed in lower-SDI countries. In 2019, the top 5 countries with the highest PIBD incidence rates were Canada (19.9 per 100 000 population), Denmark (12.4 per 100 000 population), Hungary (8.5 per 100 000 population), Austria (8.1 per 100 000 population), and the United States (7.4 per 100 000 population). Several countries experienced significant increases in incidence rates from 1990 to 2019, led by Taiwan (annual percent change 4.2%), followed by China (2.8%), Japan (2.1%), Australia (1.8%), and Hungary (1.6%).

DISCUSSION

PIBD incidence has significantly increased since 1990. High-SDI countries face higher incidence, while lower-SDI countries experience higher mortality and DALY burdens. The study underscores the need for ongoing monitoring and research to address this emerging public health issue.

Correlation of Socioeconomic and Environmental Factors With Incidence of Crohn Disease in Children and Adolescents: Systematic Review and Meta-Regression

BACKGROUND

The worldwide incidence of Crohn disease (CD) in childhood and adolescence has an increasing trend, with significant differences between different geographic regions and individual countries. This includes an increase in the incidence of CD in countries and geographic regions where CD was not previously prevalent. In response to the increasing incidence, the pediatric care landscape is facing growing challenges.

OBJECTIVE

This systematic review and meta-analysis were undertaken to comprehensively delineate the incidence rates of CD in pediatric populations across different countries and to explore potential influencing factors.

METHODS

We performed a systematic review of PubMed and Embase (via Ovid) for studies from January 1, 1970, to December 31, 2019. In addition, a manual search was performed in relevant and previously published reviews. The results were evaluated quantitatively. For this purpose, random effects meta-analyses and meta-regressions were performed to investigate the overall incidence rate and possible factors influencing the incidence.

RESULTS

A qualitative synthesis of 74 studies was performed, with 72 studies included in the meta-analyses and 52 in the meta-regressions. The results of our meta-analysis showed significant heterogeneity between the individual studies, which cannot be explained by a sample effect alone. Our findings showed geographical differences in incidence rates, which increased with increasing distance from the equator, although no global temporal trend was apparent. The meta-regression analysis also identified geographic location, UV index, and Human Development Index as significant moderators associated with CD incidence.

CONCLUSIONS

Our results suggest that pediatric CD incidence has increased in many countries since 1970 but varies widely with geographic location, which may pose challenges to the respective health care systems. We identified geographic, environmental, and socioeconomic factors that contribute to the observed heterogeneity in incidence rates. These results can serve as a basis for future research. To this end, implementations of internationally standardized and interoperable registries combined with the dissemination of health data through federated networks based on a common data model, such as the Observational Medical Outcomes Partnership, would be beneficial. This would deepen the understanding of CD and promote evidence-based approaches to preventive and interventional strategies as well as inform public health policies aimed at addressing the increasing burden of CD in children and adolescents.

TRIAL REGISTRATION

PROSPERO International prospective register of systematic reviews CRD42020168644; https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=168644.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

RR2-10.1136/bmjopen-2020-037669.

Epidemiology, validation, and clinical characteristics of inflammatory bowel disease: the ABIS birth cohort study

BACKGROUND

Birth cohort studies with linked register-based data on inflammatory bowel disease (IBD) provide opportunities to prospectively study early-life determinants of the disease. However, register-based data often lack information on clinical characteristics and rely on diagnostic algorithms. Within the All Babies in Southeast Sweden (ABIS) cohort, we examined the validity of a register-based definition of IBD, its incidence, and clinical and therapeutic characteristics at diagnosis.

METHODS

We followed 16,223 children from birth (1997-1999) until the end of 2020 for the diagnosis of IBD as defined by a minimum of two diagnostic codes for IBD in the Swedish National Patient Register (NPR). We described the incidence and cumulative incidence of IBD. Through a medical record review of cases diagnosed by the end of 2017, we examined the positive predictive value (PPV) for IBD and described its clinical characteristics and treatment.

RESULTS

By 2020, at an average age of 22.2 years, 113 participants (0.74%, 95% confidence interval [CI] = 0.61-0.89) had a register-based diagnosis of IBD, corresponding to an incidence of 31.3 per 100,000 person-years of follow-up; the incidence for Crohn's disease (CD) was 11.1 per 100,000 person-years and 15.8 for ulcerative colitis (UC). Of 77 participants with a register-based definition of IBD by the end of 2017, medical records were identified for 61 participants, of whom 57 had true IBD (PPV = 93%; 95%CI = 0.87-1.00). While oral 5-aminosalicylic acid treatment was equally common in newly diagnosed CD and UC patients, biologics were more often used for newly diagnosed CD. The median faecal calprotectin levels were 1206 mg/kg at diagnosis and 93 mg/kg at the last follow-up (P < 0.001).

CONCLUSIONS

In this population-based sample of Swedish children and young adults the cumulative IBD incidence was 0.74. The validity of register-based definition of IBD was high and supports using such data to identify IBD patients in cohort studies.

The Incidence and Prevalence of Paediatric- and Adult-Onset Inflammatory Bowel Disease in Denmark During a 37-Year Period: A Nationwide Cohort Study (1980-2017)

BACKGROUND

Incidence rates of inflammatory bowel disease [IBD] reported from developed countries are rising, with some levelling out. The aim of this study was to assess the disease burden of IBD by estimating the incidence and prevalence across age groups and projecting these to 2030 in a high-incidence country.

METHODS

Using an algorithm [incorporating ICD codes, medications and histopathology], patients [n = 69 862] diagnosed with Crohn's disease [CD] or ulcerative colitis [UC] between 1980 and 2017 were identified in the Danish National Patient Registry and included in a nationwide cohort.

RESULTS

From 1980 to 2017 the overall incidence of CD increased from 5.1 [95% CI: 4.5-5.8] to 15.6 [95% CI: 14.6-16.6] per 100 000, while the incidence of UC increased from 6.2 [95% CI: 5.5-6.9] to 27.2 [95% CI: 25.9-28.6] per 100 000. For paediatric-onset CD [pCD], the incidence increased from 1.9 [95% CI: 1.2-2.8] to 9.9 [95% CI: 8.1-11.8] per 100 000 and from 1.8 [95% CI: 1.2-2.8] to 8.7 [95% CI: 7.1- 10.5] per 100 000 for paediatric-onset UC [pUC]. In 2017, the prevalence of CD and UC was 293 [95% CI: 288-297] and 523 [95% CI: 517-528] per 100 000. For pCD and pUC, the prevalence was 35 [95% CI: 31-38] and 28 [95% CI: 26-32] per 100 000.

CONCLUSIONS

The incidence of paediatric- and adult-onset IBD in Denmark continues to increase and is among the highest in the world.

Epidemiologic trend of pediatric inflammatory bowel disease in Latin America: The Latin American Society for Pediatric Gastroenterology, Hepatology and Nutrition (LASPGHAN) Working Group

INTRODUCTION AND AIMS

The primary aim was to explore the epidemiologic trend of pediatric inflammatory bowel disease in Latin America, and the secondary aims were to obtain an overview of the diagnostic/therapeutic focus of the members of the LASPGHAN and examine the relation of case frequency to year, during the study period.

MATERIALS AND METHODS

Latin American pediatric gastroenterologists participated in an online survey, conducted through the SurveyMonkey platform, that investigated the yearly frequency of new inflammatory bowel disease patients within the time frame of 2005-2016, their disease variety, the gastrointestinal segments affected, and the diagnostic and treatment methods utilized. The correlation of new case frequency with each study year was evaluated.

RESULTS

A total of 607 patients were studied. The diagnoses were ulcerative colitis in 475 (78.3%) cases, Crohn's disease in 104 (17.1%), and inflammatory bowel disease D unclassified in 28 (4.6%). The trend in ulcerative colitis was a lineal increase in the frequency of new cases related to each study year, with a significant correlation coefficient. Pancolitis was found in 67.6% of the patients. The diagnostic methods included clinical data, endoscopy, and biopsies in more than 99% of the cases, and imaging studies were indicated selectively. Drug regimens were limited to 5-aminosalicylic acid derivatives, azathioprine, 6-mercaptopurine, infliximab, and adalimumab.

CONCLUSIONS

Pediatric inflammatory bowel disease in Latin America appears to have increased during the years included in the study period, with a predominance of moderate or severe ulcerative colitis. That lineal trend suggests the predictive likelihood of a gradual increase in the coming years, with possible epidemiologic and clinical implications.

Epidemiologic trend of pediatric inflammatory bowel disease in Latin America: The Latin American Society for Pediatric Gastroenterology, Hepatology and Nutrition (LASPGHAN) Working Group

INTRODUCTION AND OBJECTIVES

The primary aim was to explore the epidemiologic trend of pediatric inflammatory bowel disease in Latin America, and the secondary aims were to obtain an overview of the diagnostic/therapeutic focus of the members of the LASPGHAN and examine the relation of case frequency to year, during the study period.

MATERIALS AND METHODS

Latin American pediatric gastroenterologists participated in an online survey, conducted through the SurveyMonkey platform, that investigated the yearly frequency of new inflammatory bowel disease patients within the time frame of 2005 to 2016, their disease variety, the gastrointestinal segments affected, and the diagnostic and treatment methods utilized. The correlation of new case frequency with each study year was evaluated.

RESULTS

A total of 607 patients were studied. The diagnoses were ulcerative colitis in 475 (78.3%) cases, Crohn's disease in 104 (17.1%), and inflammatory bowel disease D unclassified in 28 (4.6%). The trend in ulcerative colitis was a lineal increase in the frequency of new cases related to each study year, with a significant correlation coefficient. Pancolitis was found in 67.6% of the patients. The diagnostic methods included clinical data, endoscopy, and biopsies in more than 99% of the cases, and imaging studies were indicated selectively. Drug regimens were limited to 5-aminosalicylic acid derivatives, azathioprine, 6-mercaptopurine, infliximab, and adalimumab.

CONCLUSIONS

Pediatric inflammatory bowel disease in Latin America appears to have increased during the years included in the study period, with a predominance of moderate or severe ulcerative colitis. That lineal trend suggests the predictive likelihood of a gradual increase in the coming years, with possible epidemiologic and clinical implications.

A Systematic Review and Meta-analysis of Paediatric Inflammatory Bowel Disease Incidence and Prevalence Across Europe

BACKGROUND AND AIMS

Inflammatory bowel disease [IBD] is often one of the most devastating and debilitating chronic gastrointestinal disorders in children and adolescents. The main objectives here were to systematically review the incidence and prevalence of paediatric IBD across all 51 European states.

METHODS

We undertook a systematic review and meta-analysis based on PubMed, CINAHL, the Cochrane Library, searches of reference lists, grey literature and websites, covering the period from 1970 to 2018.

RESULTS

Incidence rates for both paediatric Crohn's disease [CD] and ulcerative colitis [UC] were higher in northern Europe than in other European regions. There have been large increases in the incidence of both paediatric CD and UC over the last 50 years, which appear widespread across Europe. The largest increases for CD have been reported from Sweden, Wales, England, the Czech Republic, Denmark and Hungary, and for UC from the Czech Republic, Ireland, Sweden and Hungary. Incidence rates for paediatric CD have increased up to 9 or 10 per 100 000 population in parts of Europe, including Scandinavia, while rates for paediatric UC are often slightly lower than for CD. Prevalence reported for CD ranged from 8.2 per 100 000 to approximately 60 and, for UC, from 8.3 to approximately 30.

CONCLUSIONS

The incidence of paediatric IBD continues to increase throughout Europe. There is stronger evidence of a north-south than an east-west gradient in incidence across Europe. Further prospective studies are needed, preferably multinational and based on IBD registries, using standardized definitions, methodology and timescales.

Extraintestinal Manifestations Are Associated With Disease Severity in Pediatric Onset Inflammatory Bowel Disease

OBJECTIVES

The aim of this study was to investigate a possible association between extraintestinal manifestations (EIM) and a more severe disease course in pediatric onset inflammatory bowel disease (pIBD).

METHODS

This study compares the disease course of pIBD patients (IBD diagnosis <15 years of age) with and without EIM in a population-based cohort from Denmark. Patients diagnosed with pIBD between 1998 and 2008 were included in the study and followed until December 31, 2014. Data on phenotype, treatment, relapses, and the temporal relationship between IBD relapses and activity of EIM were collected at end of follow-up by manual revision of patient charts.

RESULTS

Of 333 pIBD patients, 14 (4.2%) had EIM at time of diagnosis and 47 (14.1%) developed EIM during follow-up. Median follow-up time was 9.6 years for patients with EIM and 8.8 years for patients without. In ulcerative colitis, EIM were associated with an increased risk of biological treatment and surgery (hazard ratio: 2.6; 95% confidence interval [CI]: 1.3-5.5, P = 0.008 and 2.9 [95% CI: 1.1-7.7, P = 0.03], respectively). In Crohn disease, EIM were associated with an increased relapse rate (1.3 [95% CI: 1.1-1.5], P = 0.001). Lastly, we found a positive temporal relationship between relapse of IBD and EIM activity.

CONCLUSION

The presence of EIM is associated with a more severe disease course in pIBD. This should be considered when deciding treatment options, as a more aggressive treatment approach could be warranted in patients with EIM. However, prospective studies are needed to fully evaluate this.

Current global trends in the incidence of pediatric-onset inflammatory bowel disease

AIM

To perform a comprehensive review and provide an up-to-date synopsis of the incidence and trends of inflammatory bowel disease (IBD).

METHODS

We systematically searched the MEDLINE (source PubMed), EMBASE and Cochrane Library databases in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines (period: 1985-2018) to identify studies reporting population-based data on the incidence of pediatric-onset (< 19 years at diagnosis) IBD in full manuscripts. Two authors carried out screening and data extraction. Choropleth interactive maps and temporal trends were used to illustrate the international differences and incidences of and changes in IBD and subtypes.

RESULTS

In total, one hundred forty studies reporting data from 38 countries were considered in this review. The highest annual pediatric incidences of IBD were 23/100000 person-years in Europe, 15.2/100000 in North America, and 11.4/100000 in Asia/the Middle East and Oceania. The highest annual incidences of Crohn's disease (CD) were 13.9/100000 in North America and 12.3/100000 in Europe. The highest annual incidences of ulcerative colitis (UC) were 15.0/100000 in Europe and 10.6/100000 in North America. The highest annual incidences of IBD-unclassified (IBD-U) were 3.6/100000 in Europe and 2.1/100000 in North America. In the time-trend analyses, 67% of CD, 46% of UC and 11% of IBD-U studies reported an increasing incidence (P < 0.05). The risk of IBD is increasing among first-generation of migrant populations.

CONCLUSION

Globally, the incidence of IBD varies greatly by geographical areas. The steadily increasing incidence of pediatric IBD over time indicates its emergence as a global disease, suggesting that studies should investigate the environmental risk factors among pediatric cohorts.

Diagnosis and management of inflammatory bowel disease in children

Inflammatory bowel diseases (IBD), including Crohn's disease and ulcerative colitis, are lifelong conditions that often begin in childhood. The implications of IBD are of particular importance in children because of the potential negative effects on growth, development, psychosocial function, and overall wellbeing. The key management strategy is to achieve sustained control of intestinal inflammation and monitor for potential complications of the disease and side effects of therapies. Overall, the evidence on the management of IBD in children is less extensive than in adults, but good quality multicenter studies and various guidelines and society consensus statements are available. This review summarizes the evidence on the pathophysiology, diagnosis, and approaches to management of children and adolescents with IBD.

Prevalence of paediatric inflammatory bowel disease in Sweden: a nationwide population-based register study

BACKGROUND

We evaluated the impact of different case definition algorithms on the prevalence of paediatric inflammatory bowel disease (IBD), Crohn's disease (CD) and ulcerative colitis (UC) and to compare the occurrence of certain diseases compared to matched controls.

METHODS

Paediatric patients (<18 years) were identified via ICD codes for UC and CD in Swedish registers between 1993 and 2010 (n = 1432). Prevalence was defined as ≥2 IBD-related visits. Prevalence of treated children in 2010 was defined as ≥2 IBD-related visits with one visit and ≥1 dispensed IBD-related drug prescription in 2010. To test the robustness of the estimates, prevalence was also calculated according to alternative case definitions. The presence of rheumatic, hepatobiliary, pancreatic, and dermatologic diseases were compared with age-/sex-/county-of-residence-matched general population controls.

RESULTS

The IBD prevalence was 75/100,000 (CD: 29/100,000; UC: 30/100,000; patients with IBD-U: 16/100,000). Prevalence of treated disease in 2010 was 62/100,000 (CD: 23/100,000; UC: 25/100,000; patients with IBD-U: 13/100,000). When age restrictions were employed, the prevalence estimate decreased (<17y: 61/100,000, <16y: 49/100,000 and <15y: 38/100,000). Compared to general population controls (n = 8583), children with IBD had a higher prevalence of dermatologic (4.7% vs. 0.6%), hepatobiliary (including primary sclerosing cholangitis) (5.5% vs. 0.1%), pancreatic (1.7% vs. 0%) and rheumatic diseases (7.2% vs. 1.2%; all P < 0.01).

CONCLUSIONS

The overall prevalence of paediatric IBD in Sweden was similar to that in earlier regional cohorts. IBD patients had a higher prevalence of comorbid conditions than matched general population controls.

The incidence of Crohn's disease and ulcerative colitis since 1995 in Danish children and adolescents <17 years - based on nationwide registry data

OBJECTIVE

Worldwide the incidence of pediatric Crohn's disease (CD) and ulcerative colitis (UC) is suspected to be increasing. Based on unselected nationwide register data the aim of this study is to examine the change in incidence of CD and UC in children and adolescents in Denmark.

MATERIALS AND METHODS

All children and adolescents <17 years with a diagnosis of CD or UC registered in the Danish National Patient Registry from 1 January 1995 to 31 December 2013 were included. Using a Poisson regression model we estimated the incidence rate ratio (IRR) for the annual change in the incidence adjusted for gender and age. The cumulative incidence was described using Kaplan-Meier survival analyses.

RESULTS

The IRR for CD was 1.052 (95% CI: 1.039-1.065), and for UC the IRR was 1.022 (95% CI: 1.011-1.033), adjusted for age and gender. The incidence rate of CD increased during the study period to 10.0 (95% CI: 7.5-13.2) per 100,000 person years for girls and 9.4 (95% CI: 7.0-13.2) for boys, in 2013. Similar, the incidence of UC increased to 7.2 (95% CI: 5.0-9.9) per 100,000 person years for girls and 6.2 (95% CI: 4.3-8.7) for boys.

CONCLUSIONS

In a period of 19 years from 1995 to 2013 we found an increasing incidence for pediatric UC and CD, especially pronounced for CD.

The emerging global epidemic of paediatric inflammatory bowel disease--causes and consequences

Two decades ago, paediatric inflammatory bowel disease (IBD) drew only modest interest from the international paediatric community. Since then, dramatically globally increasing incidence rates have made childhood-onset IBD a priority for most paediatric gastroenterologists. The emerging pandemia of paediatric IBD has fuelled a quest to identify the recent changes in early life exposures that could explain the increasing risk for IBD amongst today's children. Treatment of children with IBD should aim for symptom control but should also target restoration of growth and prevention of pubertal delay. The paediatric IBD phenotype seems to be characterized by more extensive disease location, and some comparative studies have suggested that childhood-onset IBD also represents a more severe phenotype than the adult-onset IBD form. In this review, we analyse recent global incidence trends of paediatric IBD. We present an update on the known and suggested risk factors that could explain the emerging global epidemia of paediatric IBD. We also draw attention to differences in treatment between children and adults with IBD. Finally, we highlight latest follow-up studies that question the proposed dynamic and aggressive nature of childhood-onset IBD.

Variation in incidence of pediatric Crohn's disease in relation to latitude and ambient ultraviolet radiation: a systematic review and analysis

BACKGROUND

Pediatric Crohn's disease (CD) is a lifelong, debilitating, and costly disease. In previous studies, CD incidence increased with higher geographic latitude in the Northern Hemisphere. This may indicate a role for lower vitamin D status as a risk factor for CD. Analysis of worldwide incidence of pediatric CD has not been previously reported.

METHODS

We undertook a systematic review of population-based studies reporting incidence of pediatric CD and published between 2003 and 2013. Included studies had well-defined diagnostic criteria for CD, evidence of high case ascertainment, reported incidence according to age group, and provided a specific location. Average daily ambient ultraviolet radiation (UVR) for each location was derived from satellite data. Negative binomial regression was used to assess the association between pediatric CD incidence and latitude and ambient UVR, adjusting for the study year.

RESULTS

Twenty-eight articles provided 39 incidence data points. Incidence of pediatric CD increased with higher latitude, and in association with a greater number of months where the average daily UVR was lower than a previously published threshold of 1.488 kJ/m. Incidence of pediatric CD increased over calendar time.

CONCLUSIONS

After applying rigorous quality assessment criteria, and including only population-based studies, there was a modest increase in incidence of pediatric CD with higher latitude and greater number of months with low ambient UVR. Reporting using nonconsistent diagnostic criteria and age groups, with poorly defined geographic locations, makes it difficult to compare data across different studies.

Temporal trends in non-stricturing and non-penetrating behaviour at diagnosis of Crohn's disease in Örebro, Sweden: a population-based retrospective study

BACKGROUND AND AIM

The incidence of Crohn's disease (CD) is continuing to rise in several countries and in others it appears to have already levelled off after a period of increase. We updated our previous population-based study, by re-extraction of all information on patients diagnosed with CD between 1963 and 2010. Our aim was to assess temporal trends in incidence, prevalence and disease phenotype at diagnosis.

METHODS

Patients of all ages with a potential diagnosis of CD were identified retrospectively by evaluation of medical notes of all current and previous patients at the colitis clinic, Örebro University Hospital amended by computerised search in the inpatient, outpatient, primary care and histopathological records. Diagnosis was confirmed by subsequent evaluation of medical notes. Disease phenotype was defined according to the Montreal classification.

RESULTS

The incidence increased over time, especially among Crohn's disease, A1 and A3. SaTScan model revealed a statistically significant high incidence during 1991-2010 (p=0.0001). The median age at diagnosis increased from 28 (3-79) years to 37 (5-87) years (p=0.0002). The point prevalence increased from 21/10(5) (14-32) in 1965 to 267/10(5) (244-291) in 2010. Non-stricturing and non-penetrating disease at diagnosis increased from 12.5% in 1963-1965 to 82.3% in 2006-2010 (p<0.0001).

CONCLUSION

The incidence of CD increased over time, although it seemed to be plateauing during the most recent decades. A striking increase in non-stricturing, non-penetrating disease at diagnosis was observed, suggesting earlier diagnosis or phenotypic change. The observed point prevalence in 2010 is among the highest reported.

Incidence of pediatric inflammatory bowel disease in Saudi Arabia: a multicenter national study

BACKGROUND

Pediatric inflammatory bowel disease (IBD) is increasingly recognized in developing countries; however, the incidence and trend over time have not been reported.

METHODS

This retrospective study included children diagnosed with IBD in gastroenterology centers in the Kingdom of Saudi Arabia between 2003 and 2012. The date of birth, date and age at diagnosis, gender, and final diagnosis were collected on special forms. Clinical, laboratory, imaging, endoscopy, and histopathology results were reviewed to confirm the final diagnosis. Descriptive statistics were used to compare ulcerative colitis and Crohn's disease in different age groups, and significance was assessed by the chi-square test. Incidence rates and trend over time were analyzed with the assumption of Poisson distribution. The incidence rate over time was compared in 2 periods (2003-2007 and 2008-2012). A P value of <0.05 and 95% confidence intervals were used to assess the significance and precision of the estimates.

RESULTS

A total of 340 Saudi Arabian children aged 0 to 14 years were diagnosed. The mean incidence rate per 100,000 individuals was 0.2, 0.27, and 0.47 for ulcerative colitis, Crohn's disease, and IBD, respectively. Except for the 0- to 4-year age group, there was a significant increase in incidence over time.

CONCLUSIONS

Although the incidence of pediatric IBD in Saudi Arabian children is lower than suggested in the Western literature, there is a significantly increasing trend over time. However, decreased trend in the younger age group over time is identified. Prospective studies will be important to identify the risk factors for IBD in different age groups.

Incidence and paris classification of pediatric inflammatory bowel disease

New epidemiological data suggest that the incidence of inflammatory bowel disease (IBD) is increasing. As a result the burden of disease accounts for more strains to the health care system. The clinical variability queries whether disease characteristics are related to clinical outcome. Our aim was to delineate the latest results of incidence trends in pediatric IBD and to compare the first experiences with Paris Classification. Incidence of pediatric IBD has been increasing in Western Europe and in Eastern Europe. To better characterize IBD, Paris Classification was introduced and validated recently. Ileocolonic involvement is the most characteristic disease location in Crohn's disease (CD) based on applying Paris Classification. The rate of perianal disease and complicated behaviour in CD was similar. It is of interest that CD patients with colonic involvement were less likely to have stricturing disease compared with patients with ileal involvement. In addition, pancolitis dominated in ulcerative colitis (UC). However, most countries lack prospective, nationwide epidemiological studies to estimate incidence trends. This review emphasizes the importance of nationwide registries that enroll all pediatric IBD cases serving reliable data for "everyday practice." These first reports have shown that Paris Classification is a useful tool to determine the pediatric IBD phenotype.

Clinical and pathologic characteristics of inflammatory bowel disease

AIM: To investigate the clinical and pathological characteristics of inflammatory bowel disease to raise the early diagnosis of this disease.

METHODS: One hundred and twenty-two cases of inflammatory bowel disease including 101 cases of ulcerative colitis and 21 cases of Crohn's disease were analyzed.

RESULTS: Non-necrotizing granuloma, fissure ulcer and chronic inflammation were morphological features of Crohn's disease. Massive inflammatory cell infiltration in the lamina propria, destroyed glands and reduced secretion, and polyangitis were the hallmarks of ulcerative colitis.

CONCLUSION: The diagnosis of inflammatory bowel disease should be made based on endoscopic, macroscopic and clinical findings. Awareness of the clinical and pathologic features of inflammatory bowel disease can help make an early diagnosis of this disease.

Nationwide prevalence of inflammatory bowel disease in Sweden: a population-based register study

BACKGROUND

Regional studies on inflammatory bowel disease (IBD) suggest an increasing prevalence over time, but no nationwide estimate has been published so far.

AIM

To estimate the IBD prevalence in 2010 in Sweden overall, by disease, and in specific patient segments.

METHODS

Patients were identified according to international classification codes for ulcerative colitis and Crohn's disease in in-patient care (1987-2010), day surgery and nonprimary out-patient care (1997-2010) in the nationwide Swedish Patient Register.

RESULTS

Requiring two or more diagnoses of IBD in nonprimary care, a total of 61 344 individuals with physician-diagnosed IBD were alive in Sweden in 2010 (mean age 50 years; 51% men), corresponding to a prevalence of 0.65% (95% CI, 0.65-0.66). The prevalence increased with age, and peaked in women at ages 50-59 years and in men at ages 60-69 years. Adding the requirement of IBD as main (vs. main or contributory) diagnosis code, or diagnosis from an internal medicine/gastroenterology/surgery department did not change the prevalence estimate. Prevalence of actively treated disease (defined as two or more IBD-related visits, of which one occurred in 2010, plus at least one dispensed prescription of IBD-related drugs in 2010) was 0.27% (95% CI, 0.27-0.28).

CONCLUSIONS

The Swedish nationwide register-based IBD prevalence was higher compared with previous Swedish and international estimates. While prevalence estimates were robust across different case definitions, once two or more visits were required, only about one-third of prevalent patients were drawing resources from specialised care in 2010.

Inflammatory bowel disease in Icelandic children 1951-2010. Population-based study involving one nation over six decades

AIM AND BACKGROUND. We describe the changes in incidence and disease location of inflammatory bowel disease (IBD) in children in one country over six decades. Iceland is an island with centralized health information. Children with IBD are cared for in only two hospitals. Iceland is therefore well suited for nationwide epidemiologic studies. MATERIAL AND METHODS. All IBD patients 16 years and younger diagnosed in Iceland from 1950-2010 were included. Patients were identified retrospectively from 1950-1989, and prospectively from 1990-2010, by reviewing pathology and charts for all patients diagnosed with IBD. Criteria for the diagnosis of ulcerative colitis (UC) were history of blood in stools for >3 weeks, characteristic endoscopic appearance of continuous inflammation of the colon, and histologic appearance of acute and chronic inflammation of the colon without granulomata. Criteria of Crohn's disease (CD) were history of abdominal pain, blood in stools, and endoscopic, radiologic, and histologic features of CD. RESULTS. One hundred and ten children were diagnosed with IBD, 61 with UC, 44 with CD, and 5 with indeterminate disease. The median age was 13.7 ± 2.6, with sex distribution varying from decade to decade. From 1980 until 2000, there was a dramatic increase in the incidence of IBD from 1.2 per 100,000 children <16 years of age to 5.6 per 100,000. However, in the past decade, the incidence has plateaued. CONCLUSION. In this population-based pediatric study, we report an increase in the incidence of IBD from 1950-2000. Incidence in Icelandic children is lower than in published studies from other Northern European countries.

Incidence of inflammatory bowel disease in the province of Styria, Austria, from 1997 to 2007: a population-based study

BACKGROUND

The incidence of inflammatory bowel disease (IBD) varies widely between different countries. This large variation is also observed for the incidence of its main two forms, ulcerative colitis (UC) and Crohn's disease (CD). Controversy exists whether IBD incidence is increasing, especially in western countries. Currently no data are available for Austria. This study therefore aimed to evaluate for the first time the incidence of IBD over an eleven-year period in Styria, a province of Austria with a population of 1.2 million.

METHODS

All patients with an initial diagnosis of IBD between 1997 and 2007, who were Styrian residents, were eligible for this retrospective study. Data were acquired from electronically stored hospital discharge reports and individual reports by patients and physicians. According to population density Styria was divided into two rural and one urban area.

RESULTS

Throughout the study period 1527 patients with an initial diagnosis of IBD were identified. The average annual incidence was 6.7 (95% CI 6.2-7.1) per 100,000 persons per year for CD and 4.8 (95% CI 4.5-5.2) for UC. The average annual incidence increased significantly (p<0.01) for both diseases during the 11 year study period. Median age at initial diagnosis was 29 years (range 3-87) for CD and 39 years (range 3-94) for UC. At diagnosis, 8.5% of all IBD patients were <18 years of age. The incidence of both CD and UC was significantly higher in the urban area than in rural areas (CD: 8.8, 95% CI 7.8-9.8 versus 5.5, 95% CI 4.7-6.4 and 5.9, 95% CI 5.3-6.7; [p<0.001]; UC: 5.8, 95% CI 5.1-6.6 versus 4.0, 95% CI 3.4-4.7 and 4.7, 95% CI 4.1-5.4; [p=0.04]).

CONCLUSION

We observed an overall increase in the incidence of ulcerative colitis and Crohn's disease in a part of Austria during an eleven year period. IBD was more predominant in the largest urban area than in rural areas.

Emerging inflammatory bowel disease in saudi outpatients: a report of 693 cases

BACKGROUND/AIM

Inflammatory bowel disease (IBD) is a chronic disease of unknown etiology and considered traditionally as a disease of the western world. Recently, rising trends have been observed in countries previously known to have a low prevalence and incidence. The aim of this study is to collect epidemiological data on IBD outpatients and to add data from the Kingdom of Saudi Arabia (KSA) to the available IBD literature.

PATIENTS AND METHODS

The medical records of 693 Saudi patients with IBD over a period of 17 years, between 1993 and 2009, were reviewed. The demographic and clinical data and methods of diagnosis were retrieved.

RESULTS

The total number of patients in this cohort was 693. It constituted 238 (34.3%) ulcerative colitis (UC) and 455 (65.7%) Crohn's disease (CD) patients. UC was steady throughout the years, whereas only 1.2 CD patients were diagnosed per year in the first 11 years, and 73.7 per year in the last six years. The median age of UC patients was 34 years, ranging from 10 to 80 years with a peak between 21 and 40 years and in CD it was 27 years, ranging from 11 to 73 years with a peak between 11 and 30 years. There was a male preponderance of 1.5:1 and 2:1, respectively. The rest of the data is discussed in this study.

CONCLUSION

IBD is no longer a rare disease in KSA. UC is in a steady state, whereas CD is increasing significantly and far outnumbering UC.

Mycobacterium avium subsp. paratuberculosis lipophilic antigen causes Crohn's disease-type necrotizing colitis in Mice

Background: A 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced murine colitis model was developed to investigate the pathogenesis and to evaluate a method of treating human Crohn’s disease. This experimental model rapidly induces colitis similar to human Crohn’s disease lesion in a reproducible manner. However, natural exposure of the human digestive tract to TNBS is unrealistic. A novel animal model based on realistic data is eagerly anticipated in future research on pathogenesis of CD. Method: We evaluated the potency of Map antigen molecules in an effort to develop a novel colitis model using a more realistic source than TNBS. We prepared the Map antigen by ethanol extraction and developed a mouse model in a manner similar to that of the well-known TNBS-induced colitis in mice. In the experiment, seven days after subcutaneous (SC) injection of the antigen into normal C57BL/6 mice, the same antigen in 50% ethanol was injected into the colon by the transanal route with a fine cannula. Results: On the fifth day after the transanal injection, histopathological examination revealed full-thickness necrotizing colitis with erosion and ulcers; severe infiltration with neutrophils, lymphocytes, macrophages, and perforation. However, no change was detected with each single Map-antigen injection. Conclusion: The present results provide a novel animal model for research on CD and may be the key to clarifying the relationship between CD and Map. This is the first evidence that mycobacterium antigen induces necrotizing colitis.

Epidemiology of pediatric inflammatory bowel disease: a systematic review of international trends

BACKGROUND

Temporal trends in the incidence of pediatric-onset inflammatory bowel disease (IBD) are controversial and a wide range of estimates have been reported worldwide. We conducted a systematic review of research describing the epidemiology of childhood-onset IBD to assess changes in incidence rates over time and to evaluate international differences.

METHODS

The following electronic databases were searched for articles published 1950-2009: MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and Cochrane IBD/Functional Bowel Disorders Group Specialised Trial Register. All included studies reported incidence or prevalence of IBD, Crohn's disease (CD) or ulcerative colitis (UC). Two authors independently completed the data extraction form for each eligible study. Choropleth maps demonstrated the international incidence of IBD, CD, and UC. Incidence of CD and UC was graphed using data from studies reporting rates in multiple time periods.

RESULTS

The search yielded 2209 references and review resulted in 139 included studies from 32 countries. A wide range of incidence was reported internationally; however, rates of IBD were not described in most countries. Twenty-eight studies (20.1%) used statistical analysis to assess trends over time, and 77.8% reported statistically significantly increased incidence of pediatric IBD. Of studies calculating statistical trends in CD incidence, 60% reported significantly increased incidence. Of similar UC studies, 20% reported significantly increased incidence.

CONCLUSIONS

Globally rising rates of pediatric IBD (due primarily to the rising incidence of CD) was demonstrated in both developed and developing nations; however, most countries lack accurate estimates. Analyzing incidence trends may help identify specific environmental and genetic risk factors for pediatric IBD.

Paediatric inflammatory bowel disease during a 44-year period in Copenhagen County: occurrence, course and prognosis--a population-based study from the Danish Crohn Colitis Database

AIM

To describe the development in incidence, disease localization, activity, surgery and prognosis in two Danish paediatric population-based inflammatory bowel disease (IBD) cohorts comparing the time periods 1962-1987 (period I) and 1998-2006 (period II).

MATERIALS AND METHODS

Incident IBD patients below 15 years of age were included. Disease localization was classified according to the Montreal classification for ulcerative colitis (UC) patients and into small bowel, large bowel and small and large bowel combined for Crohn's disease (CD) patients. Disease activity and surgery in the first 2 years after diagnosis were assessed. Standardized cancer incidence rates and standardized mortality rates were calculated.

RESULTS

One hundred and nineteen IBD patients (77 UC and 42 CD) were included. Comparing periods II and I, the incidence rate ratios were 0.81 [95% confidence interval (CI): 0.5-1.4] and 15.6 (95% CI: 7.5-32.7) in UC and CD, respectively. The number of UC patients with extensive disease (E3) increased from period I to II (46.7 vs. 94.1%, P<0.001). No colectomies were performed in UC patients in period II compared with nine in period I (P = 0.13) within the first 2 years after diagnosis. For patients diagnosed in period I, the standardized cancer incidence rate for UC was 37.9 (95% CI: 4.6-136.7) after a median follow-up period of 26 years.

CONCLUSION

We found a significant 15-fold increase in the incidence of CD and a significant increase in the number of UC patients with extensive disease in period II compared with period I. After a median follow-up time of 26 years, a possible increased risk of colorectal cancer in UC patients was detected.

Granulocyte-monocyte adsorptive apheresis in pediatric inflammatory bowel disease: results, practical issues, safety, and future perspectives

BACKGROUND

The purpose of the study was to collect data on granulocyte-monocyte adsorptive apheresis (GMA) for the treatment of corticosteroid-dependent (SD) or corticosteroid-resistant (SR) inflammatory bowel disease (IBD) in children from 3 Nordic countries to evaluate its efficacy and safety and to assess practical issues.

METHODS

Retrospective data on 37 children treated with GMA were collected. In all, 22 children had ulcerative colitis (UC), 13 Crohn's disease (CD), and 2 had indeterminate colitis (IC). Their mean age was 13.2 years, range 5-17 years, and mean duration of disease was 2.4 years, range 1 month to 6 years. Indication for treatment in the UC group was SD in 11 cases, SR in 6 cases, and other reasons in 5 cases. The corresponding numbers in the CD group were SD in 8 cases, SR in 2 cases, and other reasons in 3 cases. In the IC group, 1 had SD and 1 was refractory to steroids, azathioprine, and infliximab. Efficacy was evaluated by severity indices: the Pediatric Ulcerative Colitis Activity Index (PUCAI) and the Pediatric Crohn's Disease Activity Index (PCDAI) and tapering of corticosteroids.

RESULTS

PUCAI and PCDAI decreased significantly in both groups after 3 months (P = 0.0007, P = 0.025). The dosage of corticosteroid was significantly reduced in the UC group by the end of GMA (P = 0.004) and this response continued after 3 months. Relapse was seen in 2 patients with UC and 3 patients with CD after 3 months follow-up.

CONCLUSIONS

GMA seems to be an effective and safe treatment in 81% of the SD or SR pediatric IBD patients, especially in those with UC.