Introduction: Worldwide, polyvalent immunoglobulin (Ig) use is rising. Together with the limited supply, this puts pressure on Ig availability. A clear overview on a country’s usage pattern helps in forecasting future needs. This research aims to provide an overview of Ig use in Belgium on the different indications, including an estimation of off-label use. Methods: Multiple data sources were used. Existing claims data were explored for reimbursed Ig use between 2010 and 2018. General 2018 sales data from the firms were compared to the reimbursed use to serve as a proxy for off-label use. Indication-specific information was retrieved via a proxy: diagnostic codes available during day-care and inpatient hospitalization. Results: In 2018, 7,556 patients had reimbursed Ig. The most prevalent indication, both in terms of patient numbers and volume, was primary immunodeficiency (PID). In Belgian hospitals, the currently reimbursed indications represented 84.4% of patients (PID [≈35%], secondary immunodeficiency [SID] [≈21%], primary immune thrombocytopenia [≈10%], chronic inflammatory demyelinating neuropathy [CIDP] [≈8%], Guillain-Barre syndrome [≈6%], Kawasaki [≈2%], streptococcal toxic shock [≈2%] and multiple motor neuropathy [≈1%]), and 82.4% of Ig use (predominantly PID [≈33%] and CIDP [≈21%]). Although no direct data on off-label use were available, crude estimates derived from indirect sources showed a proportion of around 15.4%. Conclusion: Our research offers the first comprehensive overview on Ig use in Belgium, including a detailed description of reimbursed use, as well as approximations to off-label use. In view of increasing pressure on Ig availability, better understanding Ig needs and trends, would benefit from an effective indication-specific national registry system (ideally covering both reimbursed and nonreimbursed use).
Int Arch Allergy Immunol

中文翻译：

---

揭开比利时多价免疫球蛋白的神秘面纱：我们有适应症吗？

简介：在世界范围内，多价免疫球蛋白 (Ig) 的使用正在增加。加上有限的供应，这给 Ig 的可用性带来了压力。一个国家使用模式的清晰概览有助于预测未来的需求。本研究旨在概述比利时在不同适应症上的 Ig 使用情况，包括对标签外使用的估计。方法：使用了多个数据源。探索了 2010 年至 2018 年报销 Ig 使用的现有索赔数据。将公司 2018 年的一般销售数据与报销使用进行比较，以作为标签外使用的代理。通过代理检索特定适应症的信息：日间护理和住院期间可用的诊断代码。结果：2018 年，7,556 名患者报销了 Ig。就患者数量和数量而言，最普遍的适应症是原发性免疫缺陷 (PID)。在比利时医院，目前报销的适应症占患者的 84.4%（PID [≈35%]、继发性免疫缺陷 [SID] [≈21%]、原发性免疫性血小板减少症 [≈10%]、慢性炎性脱髓鞘神经病变 [CIDP] [≈ 8%]、吉兰-巴利综合征 [≈6%]、川崎 [≈2%]、链球菌中毒性休克 [≈2%] 和多发性运动神经病 [≈1%]），以及 82.4% 的 Ig 使用（主要是 PID [ ≈33%] 和 CIDP [≈21%]）。虽然没有关于标签外使用的直接数据，但从间接来源得出的粗略估计显示比例约为 15.4%。结论：我们的研究首次全面概述了比利时的 Ig 使用情况，包括对报销使用的详细描述，以及标签外使用的近似值。鉴于 Ig 可用性的压力越来越大，更好地了解 Ig 需求和趋势，将受益于有效的特定适应症国家注册系统（理想情况下涵盖报销和非报销使用）。
Int Arch 过敏免疫