Division of Gastroenterology, Hepatology and Nutrition, Children's Hospital at Downstate, SUNY-Downstate Medical Center, Brooklyn, NY.
J Pediatr Gastroenterol Nutr. 2019 May;68(5):662-668. doi: 10.1097/MPG.0000000000002252.
Altered vascular flow is known to both play a role in the pathogenesis and influence the severity of inflammatory bowel disease (IBD). This phenomenon has been described in other systemic conditions and contributes to disease progression by facilitating inflammation and thrombosis. Microvascular dysfunction may represent an early sign of generalized vascular disease (VD). It manifests by failure to achieve a normal response of vasodilation and increased blood flow following a period of vaso-occlusion. Although thromboembolic complications are well described in IBD, their pathogenesis is not fully understood. This study sought to assess microvascular responsiveness in pediatric subjects with IBD, by recording postocclusion peripheral arterial pulsatile volume changes.
A total of 32 pediatric subjects were studied, including 16 with IBD and 16 age-matched controls. All patients with IBD were in clinical remission, and none had known VD. Vascular reactivity was evaluated using the Itamar Medical EndoPAT2000, a noninvasive device utilizing plethysmography to measure microvascular flow. Results were reported as the reactive hyperemia index (RHI), indicating post- to preocclusion pulsatile volume changes.
Baseline characteristics, including body mass index, plasma lipid levels, hemoglobin, and serum albumin, were similar in both study groups. All patients with IBD were in clinical remission, assessed by standard disease activity scoring methods. Measurements of microvascular function indicated patients with IBD exhibited a mean RHI both within the range associated with VD risk in adults (≤1.67) and significantly lower than that in controls (IBD vs control = 1.66 vs 2.02, P = 0.036).
Microvascular plethysmography is a safe and noninvasive method for assessing microvascular function in children with IBD. Patients with IBD in clinical remission demonstrate an attenuated, postocclusion microvascular hyperemic response, compared with the normal response in controls. These findings suggest pediatric IBD subjects with a mean RHI within the VD "at risk" range should be monitored for thromboembolic phenomena. Further studies in a larger patient population and over longer periods should be conducted to validate our findings and to determine the importance of these measurements in guiding IBD management.
已知血管血流改变既在炎症性肠病（IBD）的发病机制中起作用，又影响其严重程度。这种现象在其他系统性疾病中已有描述，并通过促进炎症和血栓形成而促进疾病进展。微血管功能障碍可能代表全身性血管疾病（VD）的早期迹象。它表现为在血管阻塞一段时间后，未能实现正常的血管扩张和血流增加的反应。尽管 IBD 中血栓栓塞并发症已有很好的描述，但它们的发病机制尚未完全了解。本研究旨在通过记录闭塞后外周动脉搏动性容积变化，评估儿科 IBD 患者的微血管反应性。
共纳入 32 名儿科患者，包括 16 名 IBD 患者和 16 名年龄匹配的对照者。所有 IBD 患者均处于临床缓解期，且均无已知 VD。使用 Itamar Medical EndoPAT2000 评估血管反应性，这是一种利用容积描记法测量微血管流量的非侵入性设备。结果以反应性充血指数（RHI）表示，即闭塞后与闭塞前搏动性容积变化。
两组患者的基线特征，包括体重指数、血浆脂质水平、血红蛋白和血清白蛋白，均相似。所有 IBD 患者均通过标准疾病活动评分方法评估为临床缓解。微血管功能的测量结果表明，IBD 患者的平均 RHI 均处于与成人 VD 风险相关的范围内（≤1.67），且显著低于对照组（IBD 与对照组：1.66 与 2.02，P=0.036）。
微血管容积描记法是一种安全、非侵入性的方法，可用于评估处于临床缓解期的 IBD 患儿的微血管功能。与对照组相比，处于临床缓解期的 IBD 患者表现出减弱的闭塞后微血管充血反应。这些发现表明，平均 RHI 在 VD“风险”范围内的儿科 IBD 患者应监测血栓栓塞现象。应在更大的患者群体中进行更长时间的研究，以验证我们的发现，并确定这些测量在指导 IBD 管理中的重要性。
