ABSTRACT
We evaluated the clinical value of polymerase chain reaction (PCR) for screening Pneumocystis carinii pneumonia (PCP) in non-HIV-infected immunocompromised patients. We retrospectively analyzed PCR and Grocott's methenamine silver (GMS) staining on 1044 clinical specimens obtained from 756 patients. Positive rates of PCR and GMS staining in sputum specimens were 21.1% and 9.5%, respectively (P < 0.01), and in bronchoalveolar lavage (BAL), specimens were 31.9% and 25.5%, respectively. Among 5 patient groups, the highest GMS staining and PCR positive rates were observed in immunosuppressed patients. In 28 GMS staining-positive patients, positive rates of PCR and GMS staining after a short anti-PCP treatment were 39.3% and 17.9%, respectively. In 5 patients with positive PCR but negative GMS staining results in initial sputum examination, GMS staining result turned positive in subsequent BAL specimens. In conclusion, PCR is sensitive for detection of Pneumocystis in sputum specimens and is useful for screening PCP in non-HIV-infected high-risk patients.
Subject(s)
Immunocompromised Host , Mass Screening/methods , Pneumocystis carinii/isolation & purification , Pneumonia, Pneumocystis/diagnosis , Polymerase Chain Reaction/methods , Bronchoalveolar Lavage Fluid/microbiology , Humans , Pneumocystis carinii/genetics , Retrospective Studies , Sensitivity and Specificity , Sputum/microbiology , Staining and Labeling/methodsABSTRACT
Objective To detect circulating antigen (Cag) for diagnosing neurocysticercosis. Method ELISA was performed with monoclonal antibody 4B6 against the cyst fluid antigen of Cyticercus cellulosae for detecting Cag in serum and/or cerebrospinal fluid (CSF) of patients with neurocysticercosis or with other diseases. Results In the group of 82 cases of neurocysticercosis, the positive rate of serum Cag was 79.2% (65/82) and the positive rate of CSF Cag was 100% (26/26). After chemotherapy for 20 cases with positive serum Cag, the titer of serum Cag in 17 cases dropped to zero(85% ). Cag could not be detected in specimens from patients with other diseases. Conclusion These results indicate that the determination of Cag, especially of the CSF Cag, is useful for the diagnosis of neurocysticercosis and the drop in serum Cag is a good parameter for the evaluation of the effectiveness of chemotherapy.
ABSTRACT
Objective To establish axenic cultivation of Pneumocystis carinii (P.c). Methods The organisms of P.c were isolated from the bronchoalveolar lavage fluid (BALF) of the rats with Pneumocystis carinii pneumonia (PCP) and cultured in a medium which was based on IMDM (GIBCO) supplemented with S-adenosyl-L-methionine, putrescine, N-acetyl glucosamine, putrescine, L-cysteine and L-glutamine, and newborn calf serum. The organisms cultured in the system were identified by observing the morphology of cysts in smears stained with Gomori's methenamine silver nitrate stain (GMS). Ultrastructure of the cysts/trophozoites was examined by transmission electron microscopy. The sequences of mitochondria] large ribosomal DNA subunit of the cutured organisms were compared with the Pneumocysti carinii f.sp. ratti variant isolate (GenBank No U20173) and Pneumocystis carinii f.sp.hominis (GenBank No M58605). Results Five isolates of P.carinii received from BALF of 8 rats with PCP were cultured axenically and continuously in the system. The cultured organisms could be stored in frozen condition and used to reinitiate culture, and were amplified by 19-22 times within 72 h. The morphology, ultrastructure and gene sequencing of the cultured organisms confirmed that the isolated organisms were P.carinii. Conclusion Five continuously and axenicly cultured isolates of P.carinii have been received.
