Point of Care Breath Test to Screen for Sickle Cell Disease in Developing Nations

摘要 每年有300,000多名婴儿出生时患有镰状细胞病，其中90%发生在 在发展中国家，人数最多的是尼日利亚。大多数患有SCD的儿童 5岁前死亡，但当早期SCD筛查与卫生保健管理相结合时， 死亡率可以大幅降低。不幸的是，因为全民筛查需要 对于婴儿的血液样本，很少在资源有限、费用昂贵的环境中进行 而且很难实施。一种简单、经济和便携的POC筛查测试 这被家庭很好地接受，避免了采血的需要，并且很容易整合 在不转移时间和资源的情况下， 医疗保健的其他优先事项也是迫切需要的。为此，Capnia已经修改了便携式 CoSense End潮汐一氧化碳(ETCO)监护仪，使其适用于护理点使用 作为热带气候中的SCD筛查工具。该监测器非侵入性地测量碳 呼吸中的一氧化碳，是溶血的副产品，并明确区分儿童和 或者没有SCD。因为测量可以在没有强制呼吸样本的情况下进行，所以 适用于不能可靠地跟踪样本采集的婴幼儿 命令。此外，唯一需要的一次性物品是一个便宜的鼻插管。因此， 这种简单易用的设备符合用作SCD筛查的所有理想特征 在低资源设置下的工具。为了充分准备设备并开发SCD筛查 对于商业部署，我们提出了四个目标。在目标1中，我们将确定 使用ETCO和推荐的ETCO对婴儿进行筛查的最佳年龄 他们应该被提交到进一步SCD的门槛。我们还将定义灵敏度 在尼日利亚儿童中检测SCD的特异性。在目标2中，我们将增强 CoSense-S将使其适合在尼日利亚现场使用，并开发培训材料以支持 其用于SCD筛查的商业部署。在AIM 3中的工作将测试 在尼日利亚田间条件下使用CoSense-S。我们的目标是测试和验证修改后的 监测员，CoSense-S，在尼日利亚进行SCD现场筛查。如果成功，我们将做好准备 将一种首次对SCD进行广泛筛查的设备商业化 在低资源环境下可行。

SUMMARY More than 300,000 babies are born annually with sickle cell disease (SCD), 90% of which occur in developing countries, with the largest number in Nigeria. A majority of children with SCD die before 5 years, but when early SCD screening is coupled with health care management, mortality can be reduced dramatically. Unfortunately, because universal screening requires blood samples from infants, it is rarely done in resource-limited settings where it is expensive and hard to implement. A simple, economical and portable point-of-care (POC) screening test that is well accepted by families, avoids the need for blood sampling, and is easily integrated into the existing community health care system without diverting time and resources from other healthcare priorities is critically needed. To this end, Capnia has modified the portable CoSense End Tidal Carbon Monoxide (ETCO) Monitor to make it suitable for point of care use as a SCD screening tool in tropical climates. The monitor non-invasively measures carbon monoxide in breath, a byproduct of hemolysis, and clearly distinguishes between children with or without SCD. Because measurements can be made without a forced breath sample, it is suitable for use in infants and young children who cannot reliably follow sample collection commands. Further, the only disposable item required is an inexpensive nasal cannula. Thus, this simple-to-use device meets all of the desirable characteristics for use as a SCD screening tool in low resource settings. In order to fully prepare the device and develop an SCD screening regimen for commercial deployment we propose four aims. In Aim 1 we will determine the optimal age at which infants should be screened using ETCO and a recommended ETCO threshold at which they should be referred for further SCD. We will also define the sensitivity and specificity of detecting SCD in Nigerian children. In Aim 2 we will enhance the usability of CoSense-S to make it suitable for field use in Nigeria and develop training materials to support its commercial deployment for SCD screening. Work in Aim 3 will test the reliability and ease of use of CoSense-S in field conditions in Nigeria. Our goal is to test and validate the modified monitor, CoSense-S, for SCD screening in the field in Nigeria. If successful, we will be ready to commercialize a device that will for the first time make widespread screening for SCD feasible in low resource settings.