Fungal Microbiota Composition in Inflammatory Bowel Disease Patients: Characterization in Different Phenotypes and Correlation With Clinical Activity and Disease Course

BACKGROUND

There is growing evidence of the role of the mycobiome in inflammatory bowel disease (IBD). Variations within phenotypes and activity and with prognosis have been poorly studied.

METHODS

A total of 111 individuals were prospectively enrolled: 89 IBD patients (52 ulcerative colitis and 37 Crohn's disease [CD]) and 22 healthy individuals. Disease characteristics were collected and a fecal calprotectin >100 μg/mg was considered indicative of activity. A subset of patients was followed for 6 ± 2 years. Disease course was designated as either complicated or uncomplicated based on the need of intensified medication and/or surgery. ITS sequencing was performed targeting the ITS1 region.

RESULTS

We found lower Ascomycota/Basidiomycota ratio in IBD. Patients showed a marked increase in Candida dublinensis and Ca albicans and were depleted of Aspergillus rubrobrunneus and Penicillium brevicompactum (P ≤ .001) Saccharomyces was predominant in total colitis and Penicillium in proctitis. Several Penicillium species were depleted in total colitis vs proctitis. Ileal CD patients were enriched in Debaromyces hansenii and depleted of Ca tropicalis (P ≤ .001). Ca albicans was overrepresented in inflammatory (B1) vs fibrostenosing (B2) CD. Ca dublinensis was more abundant in active patients and correlated positively with fecal calprotectin and neutrophil gelatinase-associated lipocalin, while S pastorianus correlated inversely with activity. Ca sake was associated with complicated disease and increased abundance of Cryptococcus carnescens with the need for surgery in CD.

CONCLUSIONS

This study shows important differences in the mycobiome in IBD and within phenotypes. Selected fungal species were associated with complicated disease and the need of surgery in CD. This work adds to our understanding of the role of fungi in IBD, with potential clinical implications.

"Out of the box" new therapeutic strategies for Crohn´s disease: moving beyond biologics

New treatment options beyond immunosuppression have emerged in recent years for patients with Crohn´s disease (CD), a chronic systemic condition affecting primarily the gut with great impact in the quality of life. The cause of CD is largely unknown, and a curative treatment is not yet available. In addition, despite the growing therapeutic armamentarium in recent years almost half of the patients don´t achieve a sustained response over time. Thus, new therapeutic strategies are urgently needed. In this review, we discuss the current state of promising new "out of the box" possibilities to control chronic inflammation beyond current pharmacological treatments, including: exclusive enteral nutrition, specific diets, cell therapies using T regs, hyperbaric oxygen, fecal microbiota transplantation, phage therapy, helminths, cannabis and vagal nerve stimulation. The exploration of original and novel therapeutic modalities is key to address their potential as main or complementary treatments in selected CD populations in order to increase efficacy, minimize side effects and improve quality of life of patients.

The Risk of Developing Disabling Crohn's Disease: Validation of a Clinical Prediction Rule to Improve Treatment Decision Making

BACKGROUND

Crohn's disease (CD) is characterized by the development of complications over the course of the disease. It is crucial to identify predictive factors of disabling disease, in order to target patients for early intervention. We evaluated risk factors of disabling CD and developed a prognostic model.

METHODS

In total, 511 CD patients were retrospectively analyzed. Univariate and multivariate logistic regression analyses were used to identify demographic, clinical, and biological risk factors. A predictive nomogram model was developed in a subgroup of patients with noncomplicated CD (inflammatory pattern and no perianal disease).

RESULTS

The rate of disabling CD within 5 years after diagnosis was 74.6%. Disabling disease was associated with gender, location of disease, requirement of steroids for the first flare, and perianal lesions. In the subgroup of patients (310) with noncomplicated CD, the rate of disabling CD was 80%. In the multivariate analysis age at onset <40 years (OR = 3.46, 95% confidence interval [CI] = 1.52-7.90), extensive disease (L3/L4) (OR = 2.67, 95% CI = 1.18-6.06), smoking habit (OR = 2.09, 95% CI = 1.03-4.27), requirement of steroids at the first flare (OR = 2.20, 95% CI = 1.09-4.45), and albumin (OR = 0.59, 95% CI = 0.36-0.96) were associated with development of disabling disease. The developed predictive nomogram based on these factors presented good discrimination, with an area under the receiver operating characteristic curve of 0.723 (95% CI: 0.670-0.830).

CONCLUSION

We identified predictive factors of disabling CD and developed an easy-to-use prognostic model that may be used in clinical practice to help identify patients at high risk and address treatment effectively.

Gammadelta T cells as a predictor of surgical relapse of Crohn's disease

BACKGROUND

We recently demonstrated a decrease in the overall lymphocyte population in the peripheral blood of patients with CD compared to healthy controls and this decrease is more evident in γδ T lymphocytes. The percentages of T cell subsets could reflect the risk of surgical relapse in CD patients. The aim of this study is to study the correlation between αβ and γδ T cell subsets in the peripheral blood of patients with CD and the risk for surgery during follow up.

METHODS

A prospective study of 102 patients with CD compared with 102 healthy subjects (control group) matched by age and sex was conducted. Lymphocytic populations of CD3+, CD4+, CD8+, CD56+, and αβ and γδ T cell subsets were measured in the peripheral blood of all participants.

RESULTS

We found evidence of a relationship between lower γδ T cell levels and risk of surgical relapse in CD. The lowest subsets observed in CD patients with surgical relapse were CD3+γδ, CD3+CD8+γδ and CD3+CD56+γδT cells. We observed a relationship between a decrease in γδ T cells and the most severe forms of the disease. The lowest levels of CD3+γδ and CD3+CD8+γδT cells were observed in the fistulizing phenotype.

CONCLUSIONS

The deficit of γδ T cells was related with the severity and the risk for surgical relapse in CD patients. Patients with CD3+γδ deficit were more prone to surgery than patients without this deficit. These results suggest that γδ T cells could be used as markers of poor prognosis of CD following the diagnosis of the disease.

B1a Lymphocytes (CD19+CD5+) Deficiency in Patients with Crohn's Disease and Its Relation with Disease Severity

BACKGROUND/AIMS

B1a cells (CD19+CD5+) are considered elements of the innate immune system. The aim of this study was to evaluate the frequency of B1a cells in the peripheral blood of patients with Crohn's disease (CD) and its relation with disease severity.

METHODS

In this prospective study, a total of 128 subjects (64 CD patients and 64 healthy controls) were studied. B1a cells in peripheral blood, CD Activity Index, and Simple Endoscopic Score of B1a cells were studied.

RESULTS

A significant decrease of B1a cells in peripheral blood was observed in patients with CD versus controls (p = 0.002), especially in perforating or penetrating patterns (p = 0.017). A lower frequency of B1a cells is related to increased endoscopic severity (Spearman's Rho: -0.559, p = 0.004). The mean frequency of B1a cells in patients with pre- and post-study surgery was significantly lower than that in patients who did not undergo surgery (p = 0.050 and p = 0.026, respectively).

CONCLUSIONS

The B1a cell count in peripheral blood is lower in CD patients. This decrease is directly related to the severity of the disease (penetrating or perforating, Simple Endoscopy Score and surgery complication). These results pointed to the fact that B1a cells play an important role in immune protection in CD.

Determination of Anti-Anisakis Simplex Antibodies and Relationship with αβ and γδ Lymphocyte Subpopulations in Patients with Crohn's Disease

BACKGROUND

The etiology of Crohn's disease (CD) is still unknown although new theories are based on defects in innate immunity. We have previously shown a decrease in γδ T cells in CD patients. Previous studies have shown a high prevalence of anti-A. simplex immunoglobulins in CD patients. The diminution of γδ T cells in the peripheral blood and intestinal mucosa of CD patients may create a state of immunosuppression that would facilitate A. simplex infection.

AIMS

To study the antibody responses to Anisakis antigens in Crohn's disease patients and its relationship with αβ and γδ T cell subsets.

METHODS

We recruited 81 CD patients and 81 healthy controls. αβ and γδ T cell subsets and anti-A. simplex antibodies were measured.

RESULTS

Levels of anti-A. simplex IgG and IgM were significantly increased in CD patients. Almost 20% of CD patients were positive for IgG and IgM anti-A. simplex versus only 3.7 and 2.5%, respectively, in normal subjects. However, lower specific IgA levels were observed in the group of CD patients versus healthy subjects. We found an association between CD3 + CD8 + γδ subset and IgM anti-A. simplex levels. In ileal cases and stricturing behavior of CD, we observed the highest levels of specific antibodies with the exception of anti-A. simplex IgA.

CONCLUSIONS

The relationship of specific antibodies with a γδ T cell deficiency makes these cell candidates to play a role in the immune response against Anisakis. In addition, anti-Anisakis antibodies could be considered as markers of risk of progression in CD.

Information resources used by patients with inflammatory bowel disease: Satisfaction, expectations and information gaps

BACKGROUND AND PURPOSE

Information received by IBD patients about their disease is of particular importance. The objective of the study was to determine the information resources these patients used, together with their perceived information gaps and expected preferences.

PATIENTS AND METHODS

A prospective, observational, cross-sectional study conducted on IBD patients attending 13 Spanish hospitals during 2008. Patients completed a semi-structured 52-question survey.

RESULTS

Survey was adequately completed by 379 of 385 patients (98%), of whom 57% had Crohn's disease and 43% ulcerative colitis. Mean patient age was 37.9 years (range, 16-76 years). Gastroenterologists were the most commonly used resource (98%), followed by the Internet (60%), and general practitioners (50%). More than 90% reported good to excellent satisfaction with gastroenterologists, nurses, and patients' associations. Only 56% considered their information needs to be covered. The Internet was mostly used by young patients and those with a high education level. In the future, 85% of the patients would like to receive information from the gastroenterologists, and 92% by face-to-face interviews. Patients mainly want additional information on treatment (medical and surgical), clinical manifestations, cancer, and mortality risks. They also think that they are poorly informed about their social and work rights, risks of cancer and death, and research trials.

CONCLUSIONS

Patients with IBD use and prefer gastroenterologists as the main source of information, but only half of them consider their information needs to be covered.

Microsporidia and its relation to Crohn's disease. A retrospective study

BACKGROUND

The cause of Crohn's Disease (CD) remains unknown. Recently a decrease in the global lymphocyte population in the peripheral blood of CD patients has been reported. This decrease was more evident in γδ T lymphocytes, especially γδ CD8+T subsets. Furthermore, a decrease of IL-7 was also observed in these patients. We propose the hypothesis that microsporidia, an obligate intracellular opportunistic parasite recently related to fungi, in CD patients can take advantage of the lymphocytes and IL-7 deficits to proliferate and to contribute to the pathophysiology of this disease.

METHODS AND FINDINGS

In this case-control study, serum samples were collected from 36 CD patients and from 36 healthy individuals (controls), IgE and IgG anti-Encephalitozoon antibodies were determined by ELISA; and forty-four intestinal tissue samples were analyzed through real time Polymerase Chain Reaction (PCR), twenty CD patients, nine with others diseases and 15 healthy subjects. We observed that IgE anti-Encephalitozoon levels were significantly higher in patients with CD: 0.386(±0.256) vs control group, 0.201(±0.147), P<0.001. However, IgG anti-Encephalitozoon values were significantly lower in CD patients: 0.361(±0.256) vs control group, 0.876(±0.380), P<0.001. In the group of CD patients, 6/20 (30%) were positive by real time PCR for microsporidia and, all the patients of the control group were negative by real time PCR.

CONCLUSIONS

These results suggest that CD patients are a group at risk for microsporidiasis and, moreover that microsporidia may be involved as a possible etiologic factor of CD.

Deficit of gammadelta T lymphocytes in the peripheral blood of patients with Crohn's disease

BACKGROUND

Gammadelta T lymphocytes are an important component of innate immunity. Previous studies have shown their role in the development of Crohn's-like colitis in mice.

AIMS

The aim of this study was to measure the γδ T lymphocyte levels in Crohn's disease (CD) patients.

METHODS

A prospective study of 40 patients with CD compared with 40 healthy subjects (control group) matched by age and sex was undertaken. Lennard-Jones criteria were used for the diagnosis of CD. Disease activity was measured with the Crohn's disease activity index (CDAI). New patients, patients in remission, and patients with active disease were evaluated. Lymphocytic populations of CD3+, CD4+, CD8+, CD56+, CD19+, and αβ and γδ subsets were measured in the peripheral blood of all participants.

RESULTS

The levels of CD3+, CD4+, CD8+, and CD19+ lymphocytes were decreased in CD patients compared with the control group (P = 0.002, 0.049, 0.003, and 0.023, respectively). Although both γδ and αβ T lymphocytes were lower in patients with CD, γδ T subsets showed the lowest levels in CD patients (mean 0.0259 × 10(9)/l) versus healthy controls (mean 0.0769 × 10(9)/l), P < 0.001. In particular, γδ CD8+ T subsets (mean 0.0068 × 10(9)/l) had the largest difference compared to the control group (mean 0.0199 × 10(9)/l), P = 0.008.

CONCLUSIONS

There is a decrease in the global lymphocyte population in the peripheral blood of patients with CD compared to healthy controls. This decrease is more evident in γδ T lymphocytes, especially γδ CD8+ T subsets. Our conclusion is that these results support the theory that a complex alteration of immune responses that affects the total numbers and function of γδ T cells is present in CD.