Laboratório de Micologia, Instituto Nacional de Infectologia Evandro Chagas, Fundação Oswaldo Cruz, Rio de Janeiro, Brasil.
Hospital São José de Doenças Infecciosas, Fortaleza, Ceará, Brasil; Departamento de Saúde Comunitária, Faculdade de Medicina, Universidade Federal do Ceará, Fortaleza, Ceará, Brasil.
Biomedica. 2023 Aug 31;43(Sp. 1):255-266. doi: 10.7705/biomedica.7020.
Pneumocystis jirovecii is an opportunistic fungus that affects mainly people living with HIV (CD4 cell count lower than 200 cells/ml) and other immunosuppressed patients. Since P. jirovecii does not grow on routine mycological media, diagnosis of P. jirovecii pneumonia relies on indirect evidence of its presence in respiratory samples.
To associate the results of direct immunofluorescence and two molecular methods with a score to predict P. jirovecii pneumonia in patients with AIDS.
A prospective study was conducted with 40 patients. A respiratory sample collected before treatment was subjected to direct immunofluorescence using the Merifluor kit, to nested PCR targeting the mitochondrial large subunit ribosomal RNA, and to the VIASURE real-time PCR kit.
These three techniques revealed P. jirovecii in 6, 12, and 15 samples, respectively. All positive samples by direct immunofluorescence were positive by nested PCR, and all positive samples by nested PCR amplified by real-time PCR. There was a statistically significant association between the P. jirovecii pneumonia score and the molecular methods. Two patients were early diagnosed and responded well to treatment.
Molecular methods, especially real-time PCR, are recommended for early diagnosis of P. jirovecii pneumonia in AIDS patients.
卡氏肺孢子虫是一种机会性真菌，主要影响 HIV 感染者（CD4 细胞计数低于 200 个/毫升）和其他免疫功能低下的患者。由于卡氏肺孢子虫不能在常规的真菌培养基上生长，因此卡氏肺孢子虫肺炎的诊断依赖于呼吸道样本中其存在的间接证据。
将直接免疫荧光和两种分子方法的结果与评分相结合，以预测 AIDS 患者的卡氏肺孢子虫肺炎。
进行了一项前瞻性研究，共纳入 40 例患者。在治疗前采集的呼吸道样本进行 Merifluor 试剂盒直接免疫荧光检测、线粒体大亚基核糖体 RNA 巢式 PCR 检测和 VIASURE 实时 PCR 检测。
这三种技术分别在 6、12 和 15 个样本中发现了卡氏肺孢子虫。直接免疫荧光阳性的所有样本均通过巢式 PCR 检测为阳性，所有通过巢式 PCR 扩增的阳性样本均通过实时 PCR 检测为阳性。卡氏肺孢子虫肺炎评分与分子方法之间存在统计学显著关联。有 2 例患者得到早期诊断并对治疗反应良好。
推荐分子方法，尤其是实时 PCR，用于 AIDS 患者卡氏肺孢子虫肺炎的早期诊断。
