Screening with urine Histoplasma antigen test in asymptomatic patients starting TNF-alpha inhibitor therapy: a cohort study.

ABSTRACT

Background: Histoplasmosis is the second most frequent granulomatous disease in patients treated with tumor necrosis factor (TNF)-α inhibitors, second only to tuberculosis. However, there is limited information about pre-therapy screening procedures and the need for preventive treatments for patients who will start immunobiologicals. Methods: This is a cohort study that evaluated the prevalence of histoplasmosis in asymptomatic HIV-negative patients before initiation of TNF-α inhibitors by testing for Histoplasma antigen in urine samples. The patients included completed a 180-day follow-up after the initiation of the biologics to assess the onset of symptoms suggestive of histoplasmosis. Results: From January 2021 to December 2022, 54 patients who were prescribed a TNF-α inhibitor agent for treating autoimmune diseases in centers in southern Brazil were included. In the screening before therapy, the prevalence of a positive urinary Histoplasma antigen test was 14.8%. None of the 54 patients developed histoplasmosis after 6 months of immunobiological therapy, including the eight patients who tested positive. Conclusion: The prevalence of Histoplasma capsulatum infection in chronic patients may be higher than expected, but the impact of latent infection in asymptomatic patients is still uncertain, including those starting treatment with immunobiological drugs such as TNF-α inhibitors. Our study did not identify risk factors for the diagnosis of disseminated histoplasmosis in this group, including a positive result in an antigen test performed before immunobiological therapy. To date, there is no evidence to recommend routine antigen-based screening or preventive therapy for histoplasmosis before initiating a TNF-α inhibitor.

Using a urine test for fungal infection to screen people without symptoms who are about to start taking immunobiologic medications This study looked at the prevalence of histoplasmosis, a fungal infection, in asymptomatic patients who were about to start treatment with TNF-α inhibitors, which are medications used for autoimmune diseases. The researchers tested urine samples for Histoplasma antigen before the patients started the treatment and followed them for 180 days after starting the medication to see if they developed any symptoms of histoplasmosis. The study included 54 patients in southern Brazil, and they found that 14.8% of the patients tested positive for the Histoplasma antigen before starting the treatment. However, none of the patients, including those who tested positive, developed histoplasmosis during the 6-month follow-up. The researchers concluded that histoplasmosis infection may be more common in these patients than previously thought, but it's still not clear if asymptomatic patients with a positive antigen test will develop the infection when starting TNF-α inhibitor treatment. The study did not find any specific risk factors for developing histoplasmosis in this group of patients, and based on their findings, they did not recommend routine screening or preventive therapy for histoplasmosis before starting TNF-α inhibitor treatment.