6例鹦鹉热衣原体重症肺炎的临床特点分析

Clinical analysis of 6 cases of severe Chlamydia psittaci pneumonia

目的分析6例鹦鹉热衣原体重症肺炎临床特点,为诊断及治疗鹦鹉热衣原体重症肺炎提供参考。方法选择2020年6月至2020年12月由安徽医科大学第一附属医院ICU(综合ICU、RICU)收治的6例诊断为鹦鹉热衣原体重症肺炎患者,对其临床资料进行回顾性分析,总结该疾病的临床特征及诊治要点。结果 6例患者以高热、咳嗽、胸闷气促为主要临床表现起病,均有家禽接触史。血白细胞计数正常或轻度升高,淋巴细胞计数明显下降,中性粒细胞百分比、C-反应蛋白(CRP)、降钙素原(PCT)明显升高。胸部CT表现为某一肺叶或多个肺叶炎症渗出和实变,纤维支气管镜检查主要表现为气道黏膜充血水肿,气道中痰液较少。所有患者均因呼吸衰竭及感染性休克入ICU治疗。利用宏基因组学二代测序技术(m NGS)检测出肺泡灌洗液中鹦鹉热衣原体核酸序列,结合临床表现及接触史明确诊断为鹦鹉热衣原体重症肺炎。及时调整以多西环素为基础的治疗方案后病情好转,缩短了鹦鹉热衣原体重症肺炎的确诊时间和病程,减少不必要抗菌药物的使用。其中4例患者经治疗好转出院;1例患者继发嗜血细胞综合征,经地塞米松联合依托泊苷治疗后完全缓解;1例患者因继发肺炎克雷伯杆菌感染而死亡。在鹦鹉热衣原体重症肺炎中需警惕继发其他细菌感染和并发症。结论鹦鹉热衣原体感染的危险因素是家禽接触史,其临床表现、实验室检查、影像学检查无特异性。应用m NGS可提高鹦鹉热衣原体重症肺炎诊断的准确性,减少漏诊及误诊。以多西环素为基础的治疗方案对鹦鹉热衣原体重症肺炎治疗效果明显,但需警惕在病程中继发细菌感染及其他并发症。

Objective To analyze the clinical characteristics of 6 cases of severe Chlamydia psittaci pneumonia in order to provide the reference for clinical diagnosis and treatment of severe Chlamydia psittaci pneumonia. Methods 6 patients with severe Chlamydia psittaci pneumonia were treated in intensive care unit( comprehensive ICU,RICU) of the First Affiliated Hospital of Anhui Medical University from June 2020 to December 2020. The clinical data of 6 patients were retrospectively analyzed,and the clinical characteristics and main points of diagnosis and treatment of the disease were summarized. Results 6 cases of patients with high fever,cough,chest tightness,the shortness of breath as the main clinical manifestations of the disease. They had a history of contact with poultry.White blood cell count was normal or slightly increased,lymphocyte count was significantly decreased,neutrophil percentage,C-reactive protein and procalcitonin were significantly increased. Chest CT showed inflammation,exudation and consolidation in one or more lobes. Bronchoscopy showed hyperemia and edema of airway mucosa and less sputum in airway. All the patients were admitted to ICU due to respiratory failure and sepsis shock. The nucleic acid sequence of Chlamydia psittaci in bronchoalveolar lavage fluid( BALF) was detected by metagenomic next-generation sequencing( m NGS),the patients were diagnosed as severe Chlamydia psittaci pneumonia combined with clinical manifestations and contact history. After timely adjustment of doxycycline-based treatment,the disease was improved,which shortened the diagnosis time and the course of severe Chlamydia psittaci pneumonia,and reduced the use of unnecessary antibiotics. Four patients recovered after the treatment;one patient with secondary Hemophilus syndrome was completely relieved after dexamethasone combined with etoposide;one patient died of secondary Klebsiella pneumoniae infection. In severe Chlamydia psittaci infection,we should be alert to other bacterial infection and other complications. Conclusions The risk factor of Chlamydia psittaci infection is the history of poultry contact. The clinical manifestation,laboratory examination and imaging examination are not specific. The application of m NGS can improve the diagnostic accuracy of severe Chlamydia psittaci pneumonia and reduce the missed diagnosis and misdiagnosis. Doxycycline-based treatment is effective in the treatment of severe Chlamydia psittaci pneumonia,but it is necessary to be aware of the secondary bacterial infection and other complications in the course of the disease.