Ocular Manifestations of IBD: Pathophysiology, Epidemiology, and Iatrogenic Associations of Emerging Treatment Strategies Original paper

What was studied?

This review article examines the ocular extraintestinal manifestations (EIMs) of inflammatory bowel disease (IBD), with a focus on pathophysiology, epidemiology, clinical presentation, and management strategies. The study particularly emphasizes the impact of conditions like episcleritis, scleritis, and uveitis in patients with IBD, exploring their association with both disease activity and the impact of IBD treatments. The article also delves into how emerging therapies, including biologics, influence ocular health, particularly through potential iatrogenic effects, which may complicate disease management.

Who was studied?

The review synthesizes findings from various studies that involved patients diagnosed with IBD, specifically Crohn’s disease (CD) and ulcerative colitis (UC). It highlights that ocular manifestations are more common in patients with CD than UC, with variations in prevalence depending on factors like disease duration, smoking, and age. The article draws attention to studies that have examined the incidence of ocular manifestations in large cohorts, as well as research on the genetic and environmental factors that may influence the occurrence of these conditions. Gender, ethnicity, and other demographics are also considered in understanding the risk factors associated with IBD-related ocular conditions.

Most important findings

The most common ocular EIMs associated with IBD include episcleritis, uveitis, and scleritis. Episcleritis, affecting 2–5% of IBD patients, often correlates with active disease flares and typically presents with mild to moderate discomfort. Uveitis, particularly anterior uveitis, is seen in 0.5–3.5% of IBD patients and tends to occur independently of gastrointestinal symptoms, occasionally even preceding the diagnosis of IBD. The prevalence of uveitis is significantly higher in patients with CD, with a notable genetic association with the HLA-B27 allele, commonly linked to ankylosing spondylitis.

Scleritis, though rarer, is of particular concern due to its severity and the potential for ocular complications such as visual impairment or ocular perforation. Treatment of scleritis involves systemic therapy, including oral NSAIDs and corticosteroids, with immunosuppressants being used in refractory cases. Interestingly, biologics such as infliximab are effective in treating ocular manifestations like episcleritis, though they may also paradoxically trigger new cases of uveitis.

Key implications

The findings underscore the need for heightened awareness and early detection of ocular manifestations in IBD patients, as these conditions can occur independently of gastrointestinal symptoms and may precede the diagnosis of IBD. The risk of ocular complications is significant, with conditions like scleritis potentially leading to irreversible vision damage. This highlights the importance of multidisciplinary care involving both gastroenterologists and ophthalmologists to ensure timely diagnosis and appropriate management.

Emerging treatment strategies for IBD, including biologics, offer new hope in managing ocular manifestations, but the iatrogenic risks, such as the potential for triggering uveitis, warrant caution. It is crucial for clinicians to carefully monitor ocular health in patients undergoing treatment with corticosteroids, immunomodulators, and biologics to prevent or mitigate ocular complications. Additionally, understanding the microbiome’s role in the pathogenesis of ocular EIMs and exploring microbial modulation could open new avenues for preventive and therapeutic strategies.