Association of intestinal granulomas with smoking, phenotype, and serology in Chinese patients with Crohn's disease

The detection rate of granulomas differs between intestinal segments and lesions in Chinese patients with Crohn's disease

BACKGROUND

Crohn's disease (CD) is characterized by non-caseating intestinal granulomas. However, the reported detection rate of granulomas on endoscopy is low. This study aimed to analyze the differences in the detection rate of granulomas in different intestinal segments and lesions in Chinese patients with CD to improve the detection rate of granulomas in clinical practice.

PATIENTS AND METHODS

113 patients with CD were analyzed retrospectively. Patients were divided into two groups: those with (n = 51) and without granulomas (n = 62) on endoscopic biopsies. Clinical information was collected from the medical records, including age; erythrocyte sedimentation rate (ESR); C-reactive protein (CRP), albumin, and hemoglobin (Hb) levels; platelet count; disease course; sex; smoking history; related operation history; Montreal classification; and lesion location, size, and shape.

RESULTS

The detection rates of granulomas in different lesion shapes were significantly different (P < 0.001), with those of longitudinal ulcers and circular ulcers being higher than those of erosion and irregular ulcers. We also found that the detection rates of granulomas in ascending colon and sigmoid colon were relatively higher than other segments of the intestine, however, the difference was not statistically significant (P = 0.716). Additionally, age, sex, smoking history, Montreal classification, related surgical history, disease course, and serum biochemical indicators (ESR; platelet count; and CRP, albumin, and Hb levels) were not significantly different between the two groups.

CONCLUSIONS

The detection rate of granulomas in patients with CD is related to the morphology of the intestinal lesions. Meanwhile, lesion location may be correlated with the detection rate of granulomas.

Clinical characteristics of Crohn's disease in a cohort from Saudi Arabia

Objective:

In Saudi Arabia, there are limited studies on the clinical characteristics of patients specifically with Crohn's disease (CD). This study was conducted to describe the clinical characteristics of CD at a tertiary care center in Jeddah, Saudi Arabia.

Methods:

This retrospective study included all patients aged >14 years who had a definitive diagnosis of CD and were managed at King Abdulaziz University Hospital, Jeddah, Saudi Arabia, between 2012 and 2018. Data were collected for the following categories: clinical, laboratory, radiological, histological features at presentation, and disease-related complications.

Results:

The study included 245 newly diagnosed CD patients, aged 14–73 years (median: 26.3 years). All subjects presented with abdominal pain. Majority of the patients (59.7%) received a definitive diagnosis of CD >3 months after the onset of symptoms; 15.1% were initially suspected to have intestinal tuberculosis. Diarrhea and bleeding per rectum were reported in 60.8% and 49.7% of the patients, respectively. Sacroiliitis was the most frequent extraintestinal manifestations (11.4%). In terms of disease location, the terminal ileum (L1) was the most affected area (46.9%). Twenty-five patients had perianal disease, of which 40% had complex fistulae and 36% had perianal abscesses. The majority had hemoglobin levels >10 g/dl (74.1%), decreased serum iron (69.6%) and ferritin (50.5%) levels, and elevated erythrocyte sedimentation rate (68.2%) and C-reactive protein (82.2%).

Conclusions:

The majority of the patients in our cohort presented with the characteristic quartet of abdominal pain, weight loss, fever, and diarrhea. This study also found a significant number of patients with CD in Saudi Arabia experience diagnostic delay, which may contribute to disease morbidity and complications. These findings highlight the need for future studies to determine factors influencing this diagnostic delay.

Clinical significance of granulomas in Crohn's disease: A systematic review and meta-analysis

BACKGROUND AND AIM

Epithelioid granuloma is one hallmark used to histologically diagnose Crohn's disease (CD). However, the clinical significance of granulomas in CD is unclear. Therefore, we performed a meta-analysis to compare the clinical features with CD according to the presence of granulomas.

METHODS

A literature search in PubMed, EMBASE, and Cochrane databases was performed on manuscripts published until October 2018. We included studies that met the following inclusion criteria: (i) patient: patients with CD; (ii) exposure: granulomas on the pathology; (iii) comparator: no granulomas; and (iv) outcomes: disease location, disease behavior, perianal disease, disease activity, use of biologics, and CD-associated hospitalization, surgery.

RESULTS

Nineteen studies met our inclusion criteria. Granulomas in CD patients were associated with a higher proportion of ileocolonic disease (odds ratio [OR]: 1.49, 95% confidence interval [CI]: 1.21-1.83), a higher proportion of upper gastrointestinal disease (OR: 2.25, 95% CI: 1.28-3.95), a higher proportion of penetrating behavior (OR: 1.48, 95% CI: 1.09-2.01), a higher prevalence of perianal disease (OR: 2.15, 95% CI: 1.48-3.11), and a higher severity index at presentation (standardized mean difference: 0.20, 95% CI: 0.09-0.32). In addition, the use of biologics was significantly higher in CD patients with granulomas compared with without granulomas (OR: 1.66, 95% CI: 1.07-2.59). The presence of granulomas was significantly associated with CD-associated hospitalization (OR: 3.88, 95% CI: 1.44-10.49), but not with CD-associated surgery.

CONCLUSIONS

Clinical features in CD patients were significantly different according to the presence of granulomas. It may indicate a more aggressive phenotype of CD.

Mesenteric Lymphatic Vessel Density Is Associated with Disease Behavior and Postoperative Recurrence in Crohn's Disease

PURPOSE

The aims of the present study were to examine the density of lymphatic vessels in the mesentery and to assess the predictive value of the mesenteric lymphatic vessel density for postoperative clinical recurrence.

METHODS

Ileocolonic resection specimens were obtained from 53 patients with Crohn's disease and 10 non-inflammatory bowel disease control subjects. Mesentery adipose tissues adjacent to the bowel wall were used for the histological quantification of lymphatic vessels using immunohistochemistry with the D2-40 antibody. The relationships between lymphatic vessel density and disease behavior, the presence of granulomas, the presence of creeping fat, and postoperative clinical recurrence were assessed.

RESULTS

Median lymphatic vessel density in the mesentery adjacent to inflamed or non-inflamed intestine was lower in control subjects than in Crohn's disease patients (2.13‰; interquartile range [IQR], 1.83-2.61; 8.34‰; IQR, 6.39-10.22; 4.43‰; IQR, 3.32-5.78; P ˂ 0.001). Increased mesenteric lymphatic vessel density was significantly associated with stricturing behavior, the presence of intestinal granulomas, the presence of creeping fat, and bowel thickness. Interestingly, patients with disease recurrence had an increased mesenteric lymphatic vessel density of the proximal mesenteric margin at the time of resection compared with those who did not have disease recurrence (6.23‰; IQR, 5.43-6.75 vs. 3.28‰; IQR, 2.93-4.29; P ˂ 0.001).

CONCLUSIONS

In addition to its correlation with disease behavior, bowel thickness, and the presence of intestinal granulomas and creeping fat, increased mesenteric lymphatic vessel density in the proximal margin is predictive of early clinical recurrence after surgery in patients with Crohn's disease.

Epithelioid Granulomas Associate With Increased Severity and Progression of Crohn's Disease, Based on 6-Year Follow-Up

BACKGROUND & AIMS

Epithelioid granulomas are characteristics of a subset of patients with Crohn's disease (CD), but their significance, with regard to disease progression and severity, is unclear. We investigated the relationship between granulomas and CD severity over a 6-year time period in a large cohort of patients.

METHODS

We performed a retrospective study of patients with CD seen at the Inflammatory Bowel Disease Center at the University of Pittsburgh; data were collected from 2009 through 2014 and patients were assigned to groups with and without histologic evidence of granuloma. Demographic, clinical (including disease activity, quality of life, medication use, and healthcare utilization), and laboratory data were used in association and survival analyses. Differences between groups were evaluated using the Mann-Whitney U-test for continuous variables.

RESULTS

Of 1466 patients with CD, granulomas were identified in 187 (12.8%). In the subset of patients who underwent surgery, 21.0% had granulomas. The presence of granuloma was associated with increased serum levels of c-reactive protein (odds ratio [OR], 2.9; 95% CI, 2.078-4.208; P < .0001), younger mean age at diagnosis (23.6 ± 11.3 years in patients with granulomas vs 27.9 ± 13.3 years in patients without; P = .0005), higher rates of stricturing or penetrating disease phenotype, higher rates of steroid and narcotic use, and higher healthcare utilization. Among patients that underwent surgery, the presence of granulomas was associated with need for repeat surgery during the 6-year observation period (OR, 2.5; 95% CI, 1.54-4.02; P = .0002). Infliximab use was associated with detection of granuloma in a significantly lower proportion of surgical specimens compared to patients who had not been treated with a biologic agent (OR, 0.22; 95 CI, 0.05-0.97; P = .03).

CONCLUSIONS

Epithelioid granulomas develop in less than 13% of patients with CD, and are associated with a more aggressive disease phenotype. Patients who have undergone surgery for CD and have granulomas are at increased risk for repeat surgery within 6 years.

Family history and disease outcomes in patients with Crohn’s disease: A comparison between China and the United States

AIM

To investigate the differences in family history of inflammatory bowel disease (IBD) and clinical outcomes among individuals with Crohn’s disease (CD) residing in China and the United States.

METHODS

We performed a survey-based cross-sectional study of participants with CD recruited from China and the United States. We compared the prevalence of IBD family history and history of ileal involvement, CD-related surgeries and IBD medications in China and the United States, adjusting for potential confounders.

RESULTS

We recruited 49 participants from China and 145 from the United States. The prevalence of family history of IBD was significantly lower in China compared with the United States (China: 4.1%, United States: 39.3%). The three most commonly affected types of relatives were cousin, sibling, and parent in the United States compared with child and sibling in China. Ileal involvement (China: 63.3%, United States: 63.5%) and surgery for CD (China: 51.0%, United States: 49.7%) were nearly equivalent in the two countries.

CONCLUSION

The lower prevalence of familial clustering of IBD in China may suggest that the etiology of CD is less attributed to genetic background or a family-shared environment compared with the United States. Despite the potential difference in etiology, surgery and ileal involvement were similar in the two countries. Examining the changes in family history during the continuing rise in IBD may provide further insight into the etiology of CD.

Asia Pacific Consensus Statements on Crohn's disease. Part 1: Definition, diagnosis, and epidemiology: (Asia Pacific Crohn's Disease Consensus--Part 1)

Inflammatory bowel disease (IBD) was previously thought to be rare in Asia, but emerging data indicate rising incidence and prevalence of IBD in the region. The Asia Pacific Working Group on Inflammatory Bowel Disease was established in Cebu, Philippines, at the Asia Pacific Digestive Week conference in 2006 under the auspices of the Asian Pacific Association of Gastroenterology with the goal of developing best management practices, coordinating research, and raising awareness of IBD in the region. The consensus group previously published recommendations for the diagnosis and management of ulcerative colitis with specific relevance to the Asia-Pacific region. The present consensus statements were developed following a similar process to address the epidemiology, diagnosis, and management of Crohn's disease. The goals of these statements are to pool the pertinent literature specifically highlighting relevant data and conditions in the Asia-Pacific region relating to the economy, health systems, background infectious diseases, differential diagnoses, and treatment availability. It does not intend to be all comprehensive and future revisions are likely to be required in this ever-changing field.

Presence of Granulomas in Mesenteric Lymph Nodes Is Associated with Postoperative Recurrence in Crohn's Disease

BACKGROUND

The association between the presence of granulomas in the mesenteric lymph node (MLN) and postoperative recurrent Crohn's disease (CD) is unknown. Our aim was to assess the predictive value of the presence of granulomas in MLN as well as in bowel wall for postoperative recurrence of CD.

METHODS

Patients with CD who underwent the index ileocolonic resection between 2004 and 2012 were included. Surgical pathology reports were reviewed for the presence and location of granulomas. The status of MLN granulomas was confirmed by re-review of surgical pathology specimen from randomly sampled patients by an expert pathologist. Both univariable and multivariable analyses were performed to assess the risk factors associated with postoperative recurrent CD.

RESULTS

A total of 194 patients were included. Granulomas were detected in the MLN in 23 patients (11.9%), and in the intestinal wall in 57 (29.4%). On Kaplan-Meier curve, the presence of granulomas in MLN was found to be a risk factor for postoperative endoscopic recurrence (P = 0.015) as well as surgical recurrence (P = 0.035). In contrast, granulomas in the bowel wall, which was not found to be associated with neither endoscopic recurrence (P = 0.94) or surgical recurrence (P = 0.56). On Cox proportional hazards regression analysis, the presence of MLN granulomas was independently associated with an increased risk for both postoperative endoscopic recurrence (hazard ratio [HR] = 1.91; 95% confidence interval [CI], 1.06-3.45; P = 0.031) and surgical recurrence (HR = 3.43; 95% CI, 1.18-9.99; P = 0.023).

CONCLUSIONS

The presence of granulomas in MLN but not in intestine per se was found to be an independent risk factor for recurrence in CD patients undergoing ileocolonic resection.

The Influence of Second-Hand Cigarette Smoke Exposure during Childhood and Active Cigarette Smoking on Crohn's Disease Phenotype Defined by the Montreal Classification Scheme in a Western Cape Population, South Africa

Background

Smoking may worsen the disease outcomes in patients with Crohn’s disease (CD), however the effect of exposure to second-hand cigarette smoke during childhood is unclear. In South Africa, no such literature exists. The aim of this study was to investigate whether disease phenotype, at time of diagnosis of CD, was associated with exposure to second-hand cigarette during childhood and active cigarette smoking habits.

Methods

A cross sectional examination of all consecutive CD patients seen during the period September 2011-January 2013 at 2 large inflammatory bowel disease centers in the Western Cape, South Africa was performed. Data were collected via review of patient case notes, interviewer-administered questionnaire and clinical examination by the attending gastroenterologist. Disease phenotype (behavior and location) was evaluated at time of diagnosis, according to the Montreal Classification scheme. In addition, disease behavior was stratified as ‘complicated’ or ‘uncomplicated’, using predefined definitions. Passive cigarette smoke exposure was evaluated during 3 age intervals: 0–5, 6–10, and 11–18 years.

Results

One hundred and ninety four CD patients were identified. Cigarette smoking during the 6 months prior to, or at time of diagnosis was significantly associated with ileo-colonic (L3) disease (RRR = 3.63; 95%CI, 1.32–9.98, p = 0.012) and ileal (L1) disease (RRR = 3.54; 95%CI, 1.06–11.83, p = 0.040) compared with colonic disease. In smokers, childhood passive cigarette smoke exposure during the 0–5 years age interval was significantly associated with ileo-colonic CD location (RRR = 21.3; 95%CI, 1.16–391.55, p = 0.040). No significant association between smoking habits and disease behavior at diagnosis, whether defined by the Montreal scheme, or stratified as ‘complicated’ vs ‘uncomplicated’, was observed.

Conclusion

Smoking habits were associated with ileo-colonic (L3) and ileal (L1) disease at time of diagnosis in a South African cohort.

Clinical Implications of Noncaseating Granulomas on Histology in Patients with Ileal Pouches

BACKGROUND

Granulomas are occasionally detected on biopsy specimen of the ileal pouch and their clinical implications are not clear. The aim of this study was to evaluate clinical implications of noncaseating granuloma on histology in patients with ileal pouches.

METHODS

All eligible patients with confirmed noncaseating granulomas on histology of the biopsy specimens of the pouch body, afferent limb, or cuff in our prospectively maintained Pouch Registry between 2002 and 2014 were evaluated. Demographic and clinical factors were analyzed. The disease course of those patients was evaluated.

RESULTS

Of 1564 patients in the Registry, 42 met the criteria and were included. The median duration from the pouch construction to the last visit was 9 years (range, 2-28 yr). Twenty-eight patients (66.7%) developed clinical Crohn's disease (CD) of the pouch, whereas 14 (33.3%) were classified as having histologic CD of the pouch. Six patients (21.4%) in the clinical CD of the pouch group and 4 (28.6%) in the histologic CD of the pouch group had granulomas on more than 1 endoscopy. Postoperative biological therapy was administered more in the clinical CD group than in the histologic CD group (39.3% versus 0%, P = 0.007). Pouch-related fistulae and presacral sinus were verified more in clinical CD group than the histologic CD group. However, Kaplan-Meier plot showed comparable pouch survival between clinical CD and histologic CD groups.

CONCLUSIONS

In our current study, one-third of the patients with noncaseating pouch granulomas did not develop clinical CD of the pouch. With proper medical therapy, long-term pouch outcomes appeared to be similar in those patients with clinical CD or histologic CD of the pouch.

Significance of the epithelioid granuloma in biopsies of Crohn's colitis

BACKGROUND

The relevance of granulomas in biopsy specimens from patients with Crohn's disease is largely unknown. Most previous studies have been performed on small samples and have produced conflicting results. This study was designed to compare the demographic, clinical, and histopathologic characteristics of a large cohort of documented patients with Crohn's disease with and without epithelioid granulomas.

METHODS

Data of all patients with Crohn's disease were extracted from a computerized database of 1.3 million subjects who underwent colonoscopy and had their biopsy specimens diagnosed by a single group of gastrointestinal pathologists. The influence of age, gender, patient symptoms, and histopathologic finding on the presence of granuloma was analyzed.

RESULTS

There were 10,456 patients with Crohn's disease: 952 (9%) patients harbored granulomas (cases) and 9504 (91%) patients (controls) had none. Cases were significantly younger than controls: 42.4 ± 17.9 versus 48.0 ± 16.4 years (P < 0.0001). Cases presented with more symptoms than controls (odds ratio, 95% confidence interval): diarrhea (2.29, 2.28-2.31), anemia (2.06, 2.02-2.10), vomiting (2.13, 2.07-2.19), abdominal pain (1.75, 1.72-1.78), hematochezia (1.97, 1.94-2.00), and weight loss (3.94, 3.93-3.94). In a multivariate logistic regression analysis, younger age, presence of chronic active colitis, and symptoms of weight loss remained independent statistically significant predictors for the presence of granulomas.

CONCLUSIONS

In colonic biopsies from patients with Crohn's disease, granulomas constitute a rare finding. Presence of granulomas is associated with younger patient age, more severe histopathologic expression of the underlying disease, and more clinical symptoms.

The association between race and Crohn's disease phenotype in the Western Cape population of South Africa, defined by the Montreal Classification System

BACKGROUND

Inter-racial differences in disease characteristics and in the management of Crohn's disease (CD) have been described in African American and Asian subjects, however for the racial groups in South Africa, no such recent literature exists.

METHODS

A cross sectional study of all consecutive CD patients seen at 2 large inflammatory bowel disease (IBD) referral centers in the Western Cape, South Africa between September 2011 and January 2013 was performed. Numerous demographic and clinical variables at diagnosis and date of study enrolment were identified using an investigator administered questionnaire as well as clinical examination and patient case notes. Using predefined definitions, disease behavior was stratified as 'complicated' or 'uncomplicated'.

RESULTS

One hundred and ninety four CD subjects were identified; 35 (18%) were white, 152 (78%) were Cape Coloured and 7(4%) were black. On multiple logistic regression analysis Cape Coloureds were significantly more likely to develop 'complicated' CD (60% vs. 9%, p = 0.023) during the disease course when compared to white subjects. In addition, significantly more white subjects had successfully discontinued cigarette smoking at study enrolment (31% vs. 7% reduction, p = 0.02). No additional inter-racial differences were found. A low proportion of IBD family history was observed among the non-white subjects.

CONCLUSIONS

Cape Coloured patients were significantly more likely to develop 'complicated' CD over time when compared to whites.

Clinical epidemiology and phenotypic characteristics of Crohn's disease in the central region of Saudi Arabia

BACKGROUND/AIMS

Despite the remarkable increase in the incidence of Crohn's disease among Saudis in recent years, data about Crohn's disease in Saudi Arabia are scarce. The aim of this study was to determine the clinical epidemiology and phenotypic characteristics of Crohn's disease in the central region of Saudi Arabia.

PATIENTS AND METHODS

A data registry, Inflammatory Bowel Disease Information System (IBDIS), was used to register Crohn's disease patients who presented to the gastroenterology clinics in four tertiary care centers in Riyadh, Saudi Arabia between September 2009 and February 2013. Patients' characteristics, disease location, behavior, age at diagnosis according to the Montreal classification, course of the disease, and extraintestinal manifestation were recorded.

RESULTS

Among 497 patients with Crohn's disease, 59% were males with a mean age at diagnosis of 25 years [95% Confidence Interval (CI): 24-26, range 5-75 years]. The mean duration from the time of complaint to the day of the diagnosis was 11 months, and the mean duration of the disease from diagnosis to the day of entry to the registry was 40 months. Seventy-seven percent of our patients were aged 17-40 years at diagnosis, 16.8% were ≤16 years of age, and 6.6% were >40 years of age. According to the Montreal classification of disease location, 48.8% of patients had ileocolonic involvement, 43.5% had limited disease to the terminal ileum or cecum, 7.7% had isolated colonic involvement, and 16% had an upper gastrointestinal involvement. Forty-two percent of our patients had a non-stricturing, non-penetrating behavior, while 32.8% had stricturing disease and 25.4% had penetrating disease.

CONCLUSION

Crohn's disease is frequently encountered in Saudi Arabia. The majority of patients are young people with a predilection for males, while its behavior resembled that of western societies in terms of age of onset, location, and behavior.

Review article: Ulcerative colitis, smoking and nicotine therapy

BACKGROUND

Smoking is the best-characterised environmental association of ulcerative colitis (UC). Smoking has been observed to exert protective effects on both the development and progression of UC.

AIMS

To examine the association between UC and smoking, possible pathogenic mechanisms and the potential of nicotine as a therapeutic agent in the treatment of UC.

METHODS

A literature search was conducted through MEDLINE, using the MeSH search terms 'ulcerative colitis' and 'smoking' or 'nicotine'. Relevant articles were identified through manual review. The reference lists of these articles were reviewed to include further appropriate articles.

RESULTS

Ulcerative colitis is less prevalent in smokers. Current smokers with a prior diagnosis of UC are more likely to exhibit milder disease than ex-smokers and nonsmokers. There is conflicting evidence for smokers having reduced rates of hospitalisation, colectomy and need for oral corticosteroids and immunosuppressants to manage their disease. Multiple potential active mediators in smoke may be responsible for these clinical effects, including nicotine and carbon monoxide, but the precise mechanism remains unknown. Nicotine has demonstrated variable efficacy in the induction of remission in UC when compared to placebo and conventional medicines. Despite this, the high frequency of adverse events limits its clinical significance.

CONCLUSIONS

Nicotine's application as a therapeutic treatment in ulcerative colitis is limited. Presently, it may be an option considered only in selected cases of acute ulcerative colitis refractory to conventional treatment options. This review also questions whether nicotine is the active component of smoking that modifies risk and inflammation in ulcerative colitis.

Inflammatory bowel disease in Asia: a systematic review

The incidence and prevalence of inflammatory bowel diseases (IBD), Crohn's disease (CD) and ulcerative colitis (UC), are lower in Asia than in the West. However, across Asia the incidence and prevalence of IBD has increased rapidly over the last two to four decades. These changes may relate to increased contact with the West, westernization of diet, increasing antibiotics use, improved hygiene, vaccinations, or changes in the gut microbiota. Genetic factors also differ between Asians and the Caucasians. In Asia, UC is more prevalent than CD, although CD incidence is rapidly increasing in certain areas. There is a male predominance of CD in Asia, but a trend towards equal sex distribution for UC. IBD is diagnosed at a slightly older age than in the West, and there is rarely a second incidence peak as in the West. A positive family history is much less common than in the West, as are extra-intestinal disease manifestations. There are clear ethnic differences in incidence within countries in Asia, and an increased incidence in IBD in migrants from Asia to the West. Research in Asia, an area of rapidly changing IBD epidemiology, may lead to the discovery of critical etiologic factors that lead to the development of IBD.

Granulomas in Crohn's disease: does progression through the bowel layers affect presentation or predict recurrence?

AIM

The aim of the study was to correlate the presence and pattern of distribution of granulomas in resected specimens to clinical characteristics and outcome in patients undergoing surgery for Crohn's disease.

METHOD

Patients with Crohn's disease who underwent surgical resection between 2001 and 2007 were identified. Pathology slides were reviewed for the presence, number and location of granulomas in four representative slides from each specimen.

RESULTS

Two-hundred and seven patients were identified. At a mean follow up of 14 months, 39 patients had a recurrence, 22 (57%) of whom underwent reoperation. Ninety-four (45%) patients had granulomas present in the surgical specimen. Patients with granulomas were younger (P<0.001), had a lower preoperative body mass index (P=0.037), were more likely to be female (P=0.017) and were more likely to have extra-intestinal manifestations (P=0.026) or perianal disease (P=0.012). Sites of disease and procedures performed were similar in both groups. Disease recurrence and reoperative rates were similar in both groups, as were length of stay and morbidity rates. The average number of granulomas present in each sampled pathology slide was 7.2, and there was no correlation between number of granulomas and disease severity. No link was found between the depth of involvement of the granulomas and fistulizing or stricturing disease.

CONCLUSION

Granulomas were associated with increased extra-intestinal manifestations and perianal disease, a lower body mass index and younger or female patients. There was no correlation between the presence of granulomas and disease progression or recurrence rates during the short follow-up period of this study.

New insights into gastrointestinal and hepatic granulomatous disorders

Numerous diseases that involve the gastrointestinal tract reveal the presence of granulomas on histological analysis. Granulomatous diseases can be either primary or secondary to environmental factors. Granulomas are dynamic structures composed of organized collections of activated macrophages, including epithelioid and multinucleated giant cells, surrounded by lymphocytes. The formation of granulomas is usually in response to antigenic stimulation and is orchestrated through cytokines, immune cells and host genetics. In this Review, the pathogenesis and etiologies of granulomas of the gastrointestinal tract and liver are discussed, as are the available diagnostic tools to help differentiate their various underlying etiologies. In addition, the role of granulomas in harboring latent tuberculosis is reviewed. The effects of tumor necrosis factor antagonists and interferon-α on the development of granulomas are also discussed.

Granulomas in Crohn's disease: are newly discovered genetic variants involved?

BACKGROUND

Non-caseating granulomas exist in a substantial portion of patients with Crohn's disease (CD). Several single nucleotide polymorphisms (SNPs) have been identified as a having strong association with CD, including SNPs within the autophagy related 4 homolog A (ATG4A) gene and the neutrophil cytosolic factor 4 (NCF4) gene. We hypothesized a possible association between the presence of granulomas in CD patients and variants in the ATG4A and NCF4 genes.

AIMS

To investigate whether variants in the NCF4 and ATG4A genes are associated with granuloma formation in a cohort of Israeli patients with CD, exploring demographic and clinical characteristics that differ between granuloma positive and granuloma negative patients.

METHODS

307 Israeli patients with CD were studied. Patients with CD who underwent biopsy or resection of the intestine were classified according to presence or absence of granulomas. Using PCR-RFLP we determined the allele frequency in SNP rs4821544 (NCF4 gene) and SNP rs807185 (ATG4A gene) for all patients.

RESULTS

Granulomas were found in 85 out of 307 CD patients (27%). There were no significant differences between patients with or without granulomas in allele frequency in SNPs rs4821544 and rs807185. CD Patients with granuloma were younger at diagnosis than patients without granuloma (mean age 19 vs. 27, respectively, P<0.0001) and were more likely to undergo surgery (55.3% vs. 34.8%, respectively, P=0.002).

CONCLUSIONS

No association was found between SNPs rs4821544 and rs807185 and the presence of granulomas in CD patients. Granuloma positive patients were more likely to be younger and to undergo surgery.

Meta-analysis of the role of granulomas in the recurrence of Crohn disease

PURPOSE

This study used meta-analytical techniques to compare the recurrence of granulomatous vs nongranulomatous Crohn disease.

METHODS

Comparative studies published between 1954 and 2007 of granulomatous vs nongranulomatous Crohn disease were included. Using a random effects model, end points evaluated were the number of recurrences and reoperations, and the time to recurrence and reoperation, of granulomatous vs nongranulomatous Crohn disease. Heterogeneity was assessed and sensitivity analysis was performed to account for bias in patient selection.

RESULTS

Twenty-one studies (14 nonrandomized retrospective, 7 nonrandomized prospective) reported on 2236 patients with Crohn disease, of whom 1050 (47.0%) had granulomas (granulomatous group) and 1186 (53.0%) had no granulomas (nongranulomatous group). The number of recurrences and reoperations was found to be significantly higher in the granulomatous group compared to the nongranulomatous group (odds ratio 1.37, P = .04; odds ratio 2.38, P < .001; respectively), with significant heterogeneity between studies (P = .06; P < .001; respectively). The time to recurrence and reoperation was significantly shorter in the granulomatous group compared with the nongranulomatous group (hazard ratio 1.63, P = .001; hazard ratio 1.62, P = .002; respectively), with no significant heterogeneity between studies. The number of recurrences and reoperations remained significantly higher in the granulomatous group compared to the nongranulomatous group during sensitivity analysis of higher-quality studies, more recent studies, and studies with a larger group of patients.

CONCLUSIONS

Granulomatous Crohn disease appears to be associated with a higher number of recurrences and reoperations and a shorter time to recurrence and reoperation compared to nongranulomatous Crohn disease. Because of significant heterogeneity between studies, further studies should be undertaken to confirm these findings.

Overview of inflammatory bowel disease in Australia in the last 50 years

Inflammatory diseases of the intestine, including Crohn's disease, ulcerative colitis, and celiac disease are now very common in Australia and remain major challenges for clinicians. Australian (and New Zealand) clinicians and scientists have made considerable contributions to our current understanding of these diseases over the last 50 years, including pathogenesis (such as the 'butyrate hypothesis', 'endoplasmic reticulum (ER) stress', and the identification of the peptide sequences that incite celiac disease), true population epidemiology (albeit in New Zealand), precise clinical observation, new investigative tools, innovative new potential therapies, influential clinical drug trials (such as triple antibiotics for Crohn's disease), and a dietary approach with efficacy for functional gut symptoms (the low FODMAP diet). Underpinning the success has been clinical excellence and adaptation of clinicians to the changing landscape of disease severity and therapeutic options. The future is indeed bright if such trends continue.

Distribution and manifestations of inflammatory bowel disease in Asians, Hispanics, and African Americans: a systematic review

OBJECTIVES

Although inflammatory bowel disease (IBD) has been reported worldwide, most studies have focused on Caucasian populations. Our aim was to summarize the existing epidemiological literature, identify temporal trends, and highlight areas for future research.

METHODS

We carried out a systematic review following standard guidelines to evaluate the incidence, prevalence, temporal trends, disease characteristics, and extra-intestinal manifestations (EIMs) of IBD in African American, Hispanic, and Asian adult patients. Two investigators independently identified eligible studies through 2008 using structured keyword searches in PubMed, applied several inclusion and exclusion criteria, and abstracted the data.

RESULTS

Twenty-eight publications were included, encompassing 1,272 Hispanic, 547 African American, and 35,844 Asian patients with IBD. Greater proportions of Hispanic (36.7-84.3%) and Asian (30.6-74.7%) patients were diagnosed with ulcerative colitis (UC) than with Crohn's disease (CD) compared with African Americans (27.6-40.6%). The prevalence rates of IBD in Hispanics in Puerto Rico varied between 5 (rural) and 62 (urban) per 100,000. Crude prevalence rates in Asia varied between 6 (Singapore) and 136 (South Asians in UK) per 100,000 for UC, and between 3 (Singapore) and 33 (South Asians in UK) per 100,000 for CD. Three studies reported a rising annual incidence rate among Hispanics (from 2.6 to 7.5 per 100,000) and Asians (from 0.22 to 3.62 per 100,000). Fistulizing CD was reported in nearly one-third of Hispanic patients, up to one-quarter of African-American patients, and up to one-half of Asian patients. Ileocolonic disease was the most common site of CD among the three racial/ethnic groups, with skin and joint manifestations noted as the most common EIMs.

CONCLUSIONS

Prevalence and incidence rates in Hispanics and Asians have recently increased. There are many similarities and differences in disease location and behavior among racial/ethnic groups. There is a paucity of literature on all aspects of the disease in Hispanics, in the incidence and prevalence of IBD in African Americans, and in Asians with IBD outside Asia.

Crohn's disease in India: a multicenter study from a country where tuberculosis is endemic

Although Crohn's disease is thought to be rare and intestinal tuberculosis common in India, Crohn's disease is being reported more often. However, there is a lack of systematic study on Crohn's disease from India. In this analysis of data from three inflammatory bowel disease clinics (two in northern India and one in eastern India), criteria for Crohn's disease were applied retrospectively: (1) World Health Organization (WHO) criteria; or (2) compatible histology (European Crohn's and Colitis Organization) or failure of response to 4-8 weeks of anti-tuberculosis therapy (Asia-Pacific guidelines); or (3) compatible macroscopic, radiologic, colonoscopic features (European Crohn's and Colitis Organization). Others were classified as probable Crohn's disease. The Montreal classification was used for disease phenotype. Age at onset and duration of symptoms (182 patients, 117 male) were 34.5 (+/-13.6; 7-73) years and 3.0 (+/-5.8; 0.1-36) years, respectively. Diarrhea (68%), abdominal pain (62%), and weight loss (57%) were common. The common intestinal complications were occult (27%) and overt (40%) gastrointestinal bleeding and obstruction (28%). There were 141 (78%) and 41 (22%) with definite and probable Crohn's disease respectively. Of 147 (81%) available histopathology specimens (endoscopic biopsy in 110; 75%), 31 (21%) had granuloma. Seventy-one out of 166 (43%) had received anti-tuberculosis therapy in the past. Results from the Montreal classification were as follows: age at onset, A1:A2:A3 6%:64%:30%; location of disease, L1:L2:L3:L4 32%:41%:23%:4%, and disease behavior, B1:B2:B3 51%:24%:25%. Twenty-six (15%) and 31 (17%) patients had upper gastrointestinal and perianal modifiers. The drugs used were: aminosalicylates (128, 70%), steroids (76, 42%), azathioprine (53, 29%), methotrexate (4, 2%), and salazopyrine (14, 8%). Sixty-six (36%) patients underwent surgical treatment. We concluded that the phenotype of Crohn's disease in India is very similar to that described in other regions of Asia and the West, except for a delay in diagnosis and a more complicated disease at diagnosis.

Tropical malabsorption

Malabsorption is an important clinical problem both in visitors to the tropics and in native residents of tropical countries. Infections of the small intestine are the most important cause of tropical malabsorption. Protozoal infections cause malabsorption in immunocompetent hosts, but do so more commonly in the setting of immune deficiency. Helminth infections occasionally cause malabsorption or protein-losing enteropathy. Intestinal tuberculosis, chronic pancreatitis and small-bowel bacterial overgrowth are important causes of tropical malabsorption. In recent years, inflammatory bowel disease and coeliac disease have become major causes of malabsorption in the tropics. Sporadic tropical sprue is still an important cause of malabsorption in adults and in children in South Asia. Investigations to exclude specific infective, immunological or inflammatory causes are important before considering tropical sprue as a diagnosis. This article briefly reviews the management of tropical sprue and presents an algorithm for its investigation and management.