2026 年 10 巻 2 号 p. 81-86
In some cases of Kawasaki disease (KD), low-grade fever and mildly elevated inflammatory markers persist following initial intravenous immunoglobulin (IVIg) therapy. These cases are associated with a higher incidence of coronary arterial lesions (CALs) compared to those with a favorable response to the initial treatment, emphasizing the importance of prompt inflammation resolution. However, it remains challenging to determine the optimal additional treatment in each patient. We report a case series documenting the efficacy of cyclosporine A in such instances of KD. Of the 90 patients diagnosed with KD and admitted to our institution between 2020 and 2024, 10 received cyclosporine A therapy. In these patients, a persistent fever (≥37.5°C), mild primary symptoms, and mildly elevated inflammatory markers persisted after initial IVIg administration. Cyclosporine A monotherapy was initiated, and its blood concentration was monitored. The patients’ age ranged from 3 months to 4 years and 5 months. All patients initially received administration of IVIg and moderate-dose aspirin; prednisolone was added if the IVIg resistance prediction score was ≥5. Cyclosporine A was effective in 8 of the 10 cases, and no CALs developed after cyclosporine A administration. In the remaining 2 cases where cyclosporine A was ineffective, additional treatment with IVIg and infliximab were administered. Compared with other additional treatments, cyclosporine A is less invasive, more easily achieved, and does not obscure inflammatory activity. Furthermore, cyclosporine A was safely given even in infants, without adverse events. Our findings suggest that cyclosporine A may be an effective additional treatment for KD patients with mild and persistent inflammation.
