【作者】 于永慧； 李敏； 王海燕； 孙正芸； 靳有鹏；

【Author】 YU Yong-hui,LI Min,WANG Hai-yan,SUN Zheng-yun, SUN Shu-zhen,JIN You-peng.Pediatric Intensive Care Unit of Provincial Hospital Affiliated to ShanDong University,JiNan 250021,China

【机构】 山东省立医院小儿重症医学科；

【摘要】 目的:探讨并发急性呼吸窘迫综合征的儿童重症肺孢子菌肺炎的诊断和治疗。方法:总结2例并发急性呼吸窘迫综合征的肺孢子菌肺炎患儿的临床、影像学表现、病原学检测和治疗措施,并复习相关文献。结果:两例患儿均为长期应用糖皮质激素、在激素减量过程中突然出现发热、咳嗽,病情迅速进展,很快发生进行性呼吸困难、紫绀、持续性低氧血症。肺部听诊无明显罗音。感染指标阳性,如白细胞升高、C反应蛋白升高。动脉血气分析显示单纯性低氧血症、氧合指数（PaO₂/FiO₂）均小于100mmHg。胸部高分辨CT显示双肺弥漫性毛玻璃状、细小网格状、条索状、片状高密度影,呈"雾松"征象,以弥漫性间质病变为突出特征。结合病史、临床和影像学特征,临床诊断肺孢子菌肺炎并急性呼吸窘迫综合征。给予甲氧苄氨嘧啶-磺胺甲基异噁唑[100mg/（kg.d）,分2～3次口服]治疗,甲泼尼龙2～3mg/（kg.d）分2次静脉点滴,同时积极呼吸支持,首选无创经鼻持续气道正压呼吸,不能缓解时进行机械通气,施行肺保护性通气策略,患儿病情很快好转。例2气管插管末端分泌物PCR检测证实为肺孢子菌感染。例1治疗1周后胸部影像学改变显著改善,1月后复查无肺部慢性间质病变表现。结论:接受免疫抑制剂治疗的患儿发生急性发病的弥漫性间质性肺部疾病时应高度警惕PCP的可能性。弥漫性毛玻璃样浑浊、间质病变是肺孢子菌肺炎高分辨CT的特征性表现,对临床诊断有重要的提示价值。无创获取痰标本,采用PCR技术检测是最佳的病原学诊断方法。选择甲氧苄氨嘧啶-磺胺甲基异噁唑和糖皮质激素以及积极的呼吸支持治疗临床预后良好,后期未发生慢性肺间质纤维化。更多还原

【Abstract】 Objective:This study retrospectively analyzes the diagnosis and treatment of Pneumocystis pneumonia（PCP）-induced acute respiratory distress syndrome（ARDS）.Method:The clinical manifestations,characteristic imaging,etiology detection and therapeutic measure of two children with ARDS secondary to PCP were summarized and pertinent literature was reviewed.Results:Two children both were patients received long-term glucocorticosteroid therapy one for nephrotic syndrome,the other for idiopathic thrombocytopenic purpura.In the process of corticosteroid extenuation,fever and cough occurred abruptly and the condition deteriorated rapidly,and then progressive dyspnea and cyanosis developed as did worsening hypoxemia.There were no obvious rales of lung auscultation.The infection parametes were positive,such as white blood cell elevated and C reaction protein rised.Arterial blood gas analysis showed simple hypoxemia,oxygenation index (partial pressure of oxygen in artery（PaO₂） /fraction of inspired oxygen（/FiO₂）（PaO₂/FiO₂） lower than 100mmHg.The chest radiograph and high-resolution computed tomography（HRCT） scan showed diffuse bilateral ground-glass attenuation with superimposed interlobular septal thickening and intralobular lines and patchy alveolar densities.Its outstanding characteristic was the diffuse interstitial changes.Clinic diagnosis is established through case history,clinical manifestation and chest imaging features.Trimethoprim-sulfamethoxazole 100mg/ （kg.d） was given orally and methylprednisolone （2～3mg/kg.d ivdrip ql2h） was started empirically for presumed interstitial lung disease.At the same time active breathing support was implemented. Noninvasive continuous positive airway pressure breathing was the first-line choice,otherwise endotracheal intubation and mechanical ventilation was given to those in severe respiratory distress using a‘lung protective ventilation strategy’ with lower tidal volume=6～8mL/kg body weight. Oxygenation improved dramatically soon.Case 2 was confirmed as Pneumocystis carinii infection by polymerase chain reaction（PCR） with respiratory secretion from the end of tracheal intubation.The chest imaging of Case 1 ameliorated dramatically after treatment for one week and there was no obvious chronic interstitial disease.Conclusion:The possibility of PCP should be intensively investigated in patients developing acute-onset diffuse interstitial lung disease while receiving immunosuppressive agents.Diffuse ground-glass opacity and interstitial lung disease is the characteristic HRCT finding in patients with definite or probable PCP.Using PCR technologies,when combined with less-invasive patient specimens represents the best etiology detection option.The clinical outcome was favorable by treatment with trimethoprim-sulfamethoxazole and glucocorticoids and active breathing support,and there remained no pulmonary interstitial fibrosis later.更多还原