Baughman R P, Strohofer S S, Clinton B A, Nickol A D, Frame P T
Department of Medicine, University of Cincinnati Medical Center, OH.
Arch Pathol Lab Med. 1989 Sep;113(9):1062-5.
Pneumocystis carinii pneumonia is a major cause of morbidity and mortality in immunocompromised patients. An indirect fluorescent antibody (IFA) test has been developed using monoclonal antibodies specific for antigens on the surface of P carinii. We tested the sensitivity and specificity of this IFA test for detecting P carinii in respiratory specimens of immunocompromised patients with pulmonary symptoms undergoing bronchoscopy. Both the bronchial wash and bronchoalveolar lavage specimens of patients with and without P carinii pneumonia were studied. The bronchoalveolar lavage and bronchial wash specimens were examined using modified Wright-Giemsa and methenamine silver stains. In addition, aliquots of the specimen were fixed and stained with IFA and read with a fluorescent microscope. Fifty-nine patients were found to have P carinii organisms. The bronchial wash specimen has been shown to be less sensitive than the bronchoalveolar lavage specimen for detecting the presence of P carinii. In the bronchial wash specimen from these 59 patients, only 60% had positive modified Wright-Giemsa stains, and 70% had positive methenamine silver stains. The IFA stain was positive in 93% of the specimens tested (significantly higher than the other two stains). There was only one false-positive IFA test result among the 54 patients tested with negative results. We found the IFA stain to be superior to conventional stains when examining less-than-adequate specimens, such as those from bronchial washes.
卡氏肺孢子虫肺炎是免疫功能低下患者发病和死亡的主要原因。已利用针对卡氏肺孢子虫表面抗原的单克隆抗体开发了一种间接荧光抗体（IFA）检测方法。我们检测了这种IFA检测方法在检测接受支气管镜检查且有肺部症状的免疫功能低下患者呼吸道标本中卡氏肺孢子虫的敏感性和特异性。对有或无卡氏肺孢子虫肺炎患者的支气管冲洗液和支气管肺泡灌洗标本都进行了研究。支气管肺泡灌洗和支气管冲洗标本采用改良瑞氏-吉姆萨染色和亚甲胺银染色进行检查。此外，将标本的等分试样固定并用IFA染色，然后用荧光显微镜读取结果。发现59例患者有卡氏肺孢子虫。已证明支气管冲洗标本在检测卡氏肺孢子虫存在方面比支气管肺泡灌洗标本敏感性低。在这59例患者的支气管冲洗标本中，只有60%的改良瑞氏-吉姆萨染色呈阳性，70%的亚甲胺银染色呈阳性。IFA染色在93%的检测标本中呈阳性（显著高于其他两种染色）。在54例检测结果为阴性的患者中，只有1例假阳性IFA检测结果。我们发现，在检查不太理想的标本（如支气管冲洗液标本）时，IFA染色优于传统染色。
