Abstract:

Objective　To investigate the clinical characteristics of Nocardia infection in patients with suspected pulmonary tuberculosis, and to improve the diagnosis of Nocardia pulmonary disease. Methods　A total of 115 patients with Nocardia infection and suspected pulmonary tuberculosis admitted to Guangzhou Chest Hospital from January 2020 to December 2023 were retrospectively selected as the study objects. There were 57 males and 58 females, aged 16-88 (50.26±17.26) years. According to the combination of pulmonary tuberculosis and non-tuberculous mycobacterium lung disease, 75 cases of pulmonary tuberculosis with Nocardia infection were classified as group A, 17 cases of non-tuberculous mycobacterium lung disease with Nocardia infection were classified as group B, and 23 cases of Nocardia infection alone were classified as group C. The CT imaging features of lung lesions and the occurrence of main suspected symptoms of pulmonary tuberculosis (cough, expectoration, hemoptysis, fever, shortness of breath, chest tightness, and chest pain) in the three groups were compared and analyzed. χ² test, independent sample t test, and rank sum test were used. Results　The detection time of Nocardia in group A was 4 (2,8) months after anti-tuberculosis treatment, and the detection time of Nocardia in group B was 10 (2,12) months after anti-nontuberculous mycobacterium treatment. Among the isolates, there were 113 strains of Nocardia farcinica, 1 strain of Nocardia pseudobrasiliensis, and 1 strain of Nocardia Africa/nova. CT images of the three groups showed lung consolidation, plaques, nodules, strips or hollow shadows, it was difficult to distinguish pulmonary tuberculosis, non-tuberculous mycobacterium lung disease, and Nocardia pulmonary infection. Anatomical sites involved: the incidences of multiple lobes involved in both lungs in group A, B, and C were 66.67% (50/75), 94.12% (16/17), and 69.57% (16/23), respectively, the incidence in group B was higher than that in group A (χ²=5.150, P=0.020), but there was no statistically significant difference between group A and group C or between group B and group C (χ²=0.067, P=0.796; χ²=3.683, P=0.055). There was no statistically significant difference in the incidence of suspected symptoms of pulmonary tuberculosis among the three groups (χ²=2.650, P=0.998). Conclusion　Nocardia infection is common in patients with pulmonary tuberculosis and non-tuberculous mycobacterium lung disease, but the clinical manifestations and imaging examination are difficult to distinguish, which should be paid enough attention to in clinical practice.

Key words:

Tuberculosis/lung, Non-tuberculous mycobacterial lung disease, Nocardia

摘要：

目的　探讨可疑肺结核症状患者诺卡菌感染的临床特征，以提高对诺卡菌肺病的诊断水平。方法　回顾性选取2020年1月至2023年12月广州市胸科医院收治的115例诺卡菌感染伴可疑肺结核患者作为研究对象。男57例，女58例；年龄16～88（50.26±17.26）岁。根据是否合并肺结核、非结核分枝杆菌肺病进行分组，75例肺结核合并诺卡菌感染为A组，17例非结核分枝杆菌肺病合并诺卡菌感染为B组，23例单纯诺卡菌感染为C组。比较分析3组的肺部病灶CT影像学特点和主要肺结核可疑症状（咳嗽、咳痰、咯血、发热、气促、胸闷、胸痛）的发生情况。采用χ²检验、独立样本t检验和秩和检验。结果　A组检出诺卡菌时间为抗结核治疗后4（2，8）个月，B组检出诺卡菌时间为抗非结核分枝杆菌治疗后10（2，12）个月。在诺卡菌分离株中，皮疽诺卡菌113株，类巴西诺卡菌1株，非洲/新诺卡菌1株。3组患者的CT影像均可见肺实变、斑块状、结节、条索状或空洞影，无病种特异性影像。病灶累及的解剖学部位：A、B、C组累及双肺多个肺叶的发生率分别为66.67%（50/75）、94.12%（16/17）、69.57%（16/23）；B组发生率高于A组（χ²=5.150，P=0.020）；A组与C组、B组与C组发生率比较，差异均无统计学意义（χ²=0.067，P=0.796；χ²=3.683，P=0.055）。3组主要肺结核可疑症状的发生率比较，差异无统计学意义（χ²=2.650，P=0.998）。结论　肺结核、非结核分枝杆菌肺病患者常合并诺卡菌感染，但临床表现和影像检查均难以鉴别，应高度重视。

关键词:

结核/肺, 非结核分枝杆菌肺病, 诺卡菌