Variation in tuberculosis screening and infliximab use in Kawasaki disease in Japan

This study examined nationwide variation in tuberculosis (TB) screening and infliximab (IFX) use in the management of Kawasaki disease (KD) in Japan. Immunosuppressive agents such as IFX, which is used to treat refractory KD, may elevate the risk of TB infection. Although guidance exists for IFX use in KD patients, standardized protocols for TB screening, particularly regarding test selection and timing, are lacking.

A nationwide, cross-sectional web-based survey was conducted from October 2023 to February 2025. Eligible respondents were physicians involved in the care of KD patients at institutions with at least two full-time pediatricians or clinics staffed by pediatricians or internists. The questionnaire covered four domains: respondent characteristics; TB screening practices prior to IFX administration; clinical decisions regarding IFX use in patients with active, past, or suspected TB; and preferences between originator and biosimilar IFX products.

Among 2000 invited physicians, 871 responded (response rate: 43.6%). Chest X-rays and interferon-gamma release assays (IGRAs) were frequently used before IFX administration, while the use of other tests varied. The timing of TB testing differed according to region, hospital type, and physician experience. Physicians in urban areas and university hospitals more often conducted early IGRA testing. The decision to administer IFX to patients with TB history also varied, with younger physicians and those at tertiary centers more likely to perform such administration.

Clinical practices regarding TB screening and IFX use in KD patients vary widely. While national guidance exists, our findings underscore the need for more detailed and uniformly implemented protocols to ensure safe and consistent care.