Chest Department, Cliniques Universitaires Erasme, Université Libre de Bruxelles, Brussels, Belgium.
J Allergy Clin Immunol. 2010 Oct;126(4):730-735.e2. doi: 10.1016/j.jaci.2010.06.019. Epub 2010 Aug 14.
The effects of inhaled corticosteroids (ICSs) on distal lung inflammation, as assessed by alveolar nitric oxide concentration (C(A)NO), are a matter of debate. Recently, a theoretic study suggested that acinar airway obstruction that is relieved by ICS treatment and associated with a decrease in fraction of exhaled nitric oxide (FeNO) concentration might, paradoxically, increase C(A)NO. This increase could be a hallmark effect of ICSs at the acinar level.
In the light of this new hypothesis, we studied changes in C(A)NO and FeNO after administration of ICSs.
C(A)NO and FeNO were measured before and after ICS treatment of 38 steroid-naive patients with uncontrolled asthma who showed clinical improvement after ICS therapy.
The average FeNO decreased from 78.3 to 28.9 ppb (P < .001); C(A)NO decreased from 7.7 to 4.3 ppb (P = .009). In 14 subjects (low-slope group), slope (= ΔC(A)NO/ΔFeNO) values (Δ = post-ICS - pre-ICS value) were less than the 95% normal CI (average ΔFeNO = -32.7 ppb and average ΔC(A)NO= +2.9 ppb). In this group, baseline C(A)NO was abnormally low when FeNO was taken into account. In 11 subjects (the high-slope group), the slope was above the normal interval (average ΔFeNO = -42.5 ppb and average ΔC(A)NO = -14.7 ppb).
Opposite patterns (one that was predicted) can indicate peripheral actions of ICSs; this difference might account for conflicting data reported from studies using C(A)NO to determine the peripheral action of ICSs. We show that a low C(A)NO does not preclude distal inflammation.
吸入性皮质类固醇（ICSs）对肺泡一氧化氮浓度（C（A）NO）评估的远端肺部炎症的影响仍存在争议。最近，一项理论研究表明，ICS 治疗缓解的腺泡气道阻塞并伴随着呼气一氧化氮（FeNO）浓度的降低，可能会反直觉地增加 C（A）NO。这种增加可能是 ICS 在腺泡水平上的标志效应。
鉴于这一新假设，我们研究了 ICS 给药后 C（A）NO 和 FeNO 的变化。
对 38 例未经皮质类固醇治疗的哮喘患者进行了 ICS 治疗，这些患者在 ICS 治疗后表现出临床改善，我们在 ICS 治疗前和治疗后测量了 C（A）NO 和 FeNO。
FeNO 平均值从 78.3 降至 28.9 ppb（P <.001）；C（A）NO 从 7.7 降至 4.3 ppb（P =.009）。在 14 名受试者（斜率低组）中，斜率值（= ΔC（A）NO/ΔFeNO，Δ= ICS 后 - ICS 前值）低于 95%正常 CI（平均 ΔFeNO= -32.7 ppb，平均 ΔC（A）NO= +2.9 ppb）。在该组中，当考虑到 FeNO 时，C（A）NO 的基线值异常低。在 11 名受试者（斜率高组）中，斜率在正常范围内（平均 ΔFeNO= -42.5 ppb，平均 ΔC（A）NO= -14.7 ppb）。
相反的模式（一种可预测的模式）可以表明 ICS 的外周作用；这种差异可能解释了使用 C（A）NO 来确定 ICS 的外周作用的研究报告中存在的相互矛盾的数据。我们表明，低 C（A）NO 并不排除远端炎症。
