RHDNASE USE IN CYSTIC FIBROSIS PATIENTS YOUNGER THAN 5 YEARS OF AGE

囊性纤维化(CF)患者呼吸道内积聚的化脓性感染痰阻塞呼吸道，导致慢性症状性感染(1)。CF的痰中富含白细胞来源的胞外DNA，这是导致痰的异常粘弹性的重要原因(2，3)。重组人DNase I(RhDNase)是一种天然人类酶的副本，负责将细胞外DNA水化，在体外显著改变CF痰的粘弹性特性(4)。在开始治疗的几天内，使用气动驱动的手持雾化器雾化吸入重组人脱氧核糖核酸酶可改善CF患者的肺功能(5，6)。长期服用重组人脱氧核糖核酸酶也减少了呼吸道感染的非肠道抗生素治疗的需要(7)。这项调查的目的是评估重组人DNA酶在5岁以下儿童中的有效性。

Accumulation of purulent, infected sputum in the airways of patients with cystic fibrosis(CF) obstructs airways and causes chronic, symptomatic infection(1). Sputum in CF is rich in leukocyte-derived extracellular DNA that greatly contributes to the abnormal viscoelasticity of sputum (2,3). Recombinant human DNase I (rhDNase), a copy of the native human enzyme responsible for hydolyzing extracellular DNA, dramatically alters the viscoelastic properties of CF sputum in vitro (4). Aerosol administration of rhDNase with a pneumatically driven hand-held nebulizer improves pulmonary function in CF patients within days of initiating therapy (5,6). Longer-term administration of rhDNase also reduces the need for parenteral antibiotic treatment of respiratory tract infections(7). The purpose of this investigation is to evaluate the usefulness of rhDNase in children who are younger than 5 years of age.