Infliximab is a biologic agent primarily used in the management of autoimmune diseases. It is a chimeric monoclonal antibody that targets
tumor necrosis factor-alpha (TNF-α), a cytokine involved in systemic inflammation. While its primary applications are in conditions like Crohn's disease, ulcerative colitis, rheumatoid arthritis, and psoriasis, its use in patients with infectious diseases raises several important considerations.
How Does Infliximab Work?
Infliximab functions by binding to TNF-α, preventing it from interacting with its receptors on cell surfaces, thereby reducing inflammation and altering the immune response. This mechanism makes it effective in controlling chronic inflammatory conditions but also impacts the body's ability to respond to infections.What Are the Risks of Infection with Infliximab?
The primary concern with infliximab use is its potential to increase the risk of infections. By dampening the immune response, patients on infliximab are more susceptible to
opportunistic infections. These include bacterial, viral, fungal, and mycobacterial infections. Notably, there is an increased risk of
tuberculosis (TB). Patients should be screened for latent TB infection before starting therapy to prevent reactivation.
What Are the Screening Recommendations?
Prior to initiating infliximab, comprehensive screening is crucial. This typically involves a
tuberculin skin test (TST) or an
interferon-gamma release assay (IGRA) for TB, as well as a thorough history and physical examination to assess for any signs of active infection. Screening for hepatitis B and C is also recommended, given the risk of viral reactivation.
How Should Infections Be Managed in Patients on Infliximab?
Management of infections in patients receiving infliximab requires a balance between controlling the infection and managing the underlying autoimmune disease. In the case of a serious infection, discontinuation of infliximab may be necessary until the infection is resolved. Antibiotics, antivirals, or antifungals should be administered as appropriate, and close monitoring is essential.Can Infliximab Be Used in Patients with HIV?
While the use of infliximab in patients with HIV is not contraindicated, it requires careful consideration. The potential for increased susceptibility to infections must be weighed against the benefits of controlling autoimmune symptoms. Regular monitoring of
CD4 counts and viral load is recommended to ensure that HIV remains well-controlled during treatment.
Are There Any Contraindications for Infliximab?
Infliximab is contraindicated in patients with active infections, such as sepsis or chronic infections that are not well-managed. It should not be used in patients with moderate to severe heart failure. Additionally, caution is advised in patients with a history of recurrent infections or conditions that predispose them to infections.What Are the Long-term Considerations?
Long-term use of infliximab requires ongoing vigilance for infections. Patients should be educated on the signs and symptoms of infections and instructed to seek medical advice promptly if they occur. Regular follow-up with healthcare providers is essential to monitor for both infectious complications and autoimmune disease control.Conclusion
Infliximab is a valuable therapeutic agent in the management of autoimmune diseases, but its use in the context of infectious diseases necessitates a comprehensive understanding of the associated risks. Proper screening, patient education, and vigilant monitoring are critical to optimizing outcomes and minimizing the risk of serious infections. By carefully balancing the benefits and risks, infliximab can be safely incorporated into treatment regimens even in patients at risk of infections.
