The Prevalence of Ocular Extra-Intestinal Manifestations in Adults Inflammatory Bowel Disease: A Systematic Review and Meta-Analysis

Ophthalmological Manifestations in Inflammatory Bowel Diseases: Keep an Eye on It

BACKGROUND AND AIMS

Inflammatory bowel diseases (IBD) are multifactorial chronic inflammatory disorders affecting the gastrointestinal tract. However, a broad spectrum of extraintestinal manifestations (EIMs) is associated with IBD, affecting several organs and systems, such as the skin, musculoskeletal and hepatobiliary systems, and, not least, the eye. Approximately 10% of IBD patients can develop ocular EIMs (O-EIMs) with a higher prevalence in Crohn's disease (CD). Eye-redness, photophobia, pain, and blurred vision are the common symptoms, with a wide rate of severity and clinical impact on the quality of life. This narrative review aims to summarize the prevalence, pathogenesis, and current evidence-based management of O-EIMs, underlying the importance of a holistic approach and specialties collaboration for a prompt diagnosis and treatment.

METHODS

PubMed was searched up to December 2023 to identify relevant studies investigating the pathogenesis, epidemiology, and treatment of O-EIMs in IBD patients.

RESULTS

The mechanisms underlying O-EIMs are partially unknown, encompassing immune dysregulation, shared antigens between the eye and the gut, genetic predisposition, and systemic inflammation driven by high levels of interleukins and cytokines in IBD patients. The complexity of O-EIMs' pathogenesis reflects in the management of these conditions, varying from topical and systemic steroids to immunomodulatory molecules and biologic therapy, such as anti-tumor necrosis factor (TNF)-alpha. A multidisciplinary approach is the backbone of the management of O-EIMs.

Current insights on the roles of gut microbiota in inflammatory bowel disease-associated extra-intestinal manifestations: pathophysiology and therapeutic targets

Inflammatory bowel disease (IBD) is a chronic, recurrent inflammatory disease of the gastrointestinal tract. In addition to digestive symptoms, patients with IBD may also develop extra-intestinal manifestations (EIMs), the etiology of which remains undefined. The gut microbiota has been reported to exert a critical role in the pathogenesis of IBD, with a similar pattern of gut dysbiosis observed between patients with IBD and those with EIMs. Therefore, it is hypothesized that the gut microbiota is also involved in the pathogenesis of EIMs. The potential mechanisms are presented in this review, including: 1) impaired gut barrier: dysbiosis induces pore formation in the intestinal epithelium, and activates pattern recognition receptors to promote local inflammation; 2) microbial translocation: intestinal pathogens, antigens, and toxins translocate via the impaired gut barrier into extra-intestinal sites; 3) molecular mimicry: certain microbial antigens share similar epitopes with self-antigens, inducing inflammatory responses targeting extra-intestinal tissues; 4) microbiota-related metabolites: dysbiosis results in the dysregulation of microbiota-related metabolites, which could modulate the differentiation of lymphocytes and cytokine production; 5) immunocytes and cytokines: immunocytes are over-activated and pro-inflammatory cytokines are excessively released. Additionally, we summarize microbiota-related therapies, including probiotics, prebiotics, postbiotics, antibiotics, and fecal microbiota transplantation, to promote better clinical management of IBD-associated EIMs.

Occurrence of uveitis in a population-based cohort of inflammatory bowel diseases followed for 10 years: an observational study

OBJECTIVE

The coexistence of inflammatory bowel diseases (IBDs) and uveitis has been known for 100 years. The reported frequency by which these conditions appear in the same patient has varied considerably. The aim of this study was to investigate the occurrence of uveitis in a well-defined population-based cohort of patients with IBD including all age groups and followed for at least 10 years.

METHOD AND ANALYSIS

All newly diagnosed patients with ulcerative colitis and Crohn's disease in the county of Uppsala between 2005 and 2009 were prospectively followed. At the end of 2022, the medical notes were checked and all contacts with the healthcare system regarding ocular symptoms were scrutinised.

RESULTS

A total of 330 patients with ulcerative colitis and 153 patients with Crohn's disease were included in the cohort. Four hundred and forty-two of these (91.5%) could be followed for 10 years or until death. Thirteen patients with ulcerative colitis were affected by uveitis (3.9%), and one of the patients with Crohn's disease (0.7%). Most often the uveitis was diagnosed after the bowel disease (median 8.9 years, 7.7 years SD).

CONCLUSION

Low occurrence of uveitis was identified in the IBD population. All affected individuals except one were diagnosed with ulcerative colitis. Most of the patients had their eye disease around 10 years later than their IBD diagnosis. It is suggested that systemic anti-inflammatory treatment for the IBD protects against intraocular inflammation in this cohort.