Before starting infliximab, what should be screened for?

Before initiating treatment with infliximab, it is crucial to screen for latent tuberculosis (TB). This is because infliximab, a tumor necrosis factor (TNF) inhibitor used for various autoimmune conditions, can increase the risk of reactivating latent TB due to its immunosuppressive effects.

Patients with latent TB are asymptomatic and do not show active signs of the disease, but if not identified and treated before starting infliximab, there is a significant risk that the latent infection can convert to an active state once the immune response is dampened by the medication. Therefore, it is standard practice to perform a tuberculin skin test (TST) or interferon-gamma release assay (IGRA) to detect latent TB prior to therapy commencement. If the test is positive, appropriate anti-TB prophylaxis should be initiated before starting infliximab to mitigate this risk.

As for the other screening options listed, while they may still be important in a comprehensive evaluation of a patient's health status and potential risks associated with immunosuppressive therapy, the specific focus on latent TB screening is a priority due to the severe consequences of untreated TB in the context of TNF inhibitor therapy.