Study On The Laboratory Diagnosis Of Pneumocystis Carinii Pneumonia In Rat Model

IOBJECTIVEI To compare Sprague Dawley(SD) with Wistar in rat model of Pneumocystis carinii pneumonia and find applicable laboratory methods. [METHODS] SD and Wistar rats were divided into experimental group and control group randomly. The experimental group was induced by immunosuppression with twice weekly injections of hydrocortison acetate for 8 weeks. Lung tissues and bronchoalveolar lavage fluid (BALF) were collected. Smears were made from lung tissues and BALF sediments, and were stained by Giemsa. Smears were examined for identifying P.carinii organisms. P.carinii DNA extracted by conventional method was detected with PCR and PCR-ELISA. [RESULTS] Giemsa stain: The positive rates of P.carinii organisms were 89.29% and 100% in lung smears, and were 60.71% and 78.57% in BALF slides, respectively. The difference between the SD and Wistar rats was no significant (p>O.O5). The positive rates in lung smears were higher than that of BALF slides and the difference between the two methods was significant (jv~0.O5). The positive rates in lung smears from different lobes were no significant (p>O.05), but the burden of P.carinii in the right lobe is heavier than the other lobes. The organisms detected from Wistar were earlier than those of SD (19d128d). The control group was negative. PCR: The positive rates in lung tissues were 96.43% and 100%, and were 96.43% and 100% in BALF, respectively. There were no differences (p>O.OS). The control group had one positive in SD and was negative in Wistar. PCR-ELISA: The positive rates were 96.43% and 100% in lung tissues, and were 96.43% and 100% in BALF, respectively. The difference between them was no significant (p>O.O5). The control group had one positive in lung tissues and BALF respectively. ICONCOUSIONS] SD and Wistar rats had no significant difference inIll#animal model of P.carinii, however Wistar was more quickly than SD in being detected. The positive rates in lung smears were higher than BALF slides. There were no relation between the positive rates of lung smears and the position of lung lobes. PCR and PCR-ELISA are sensitive and specific, secure and easy-used methods.Chen ShengxiaDirected by TANG Xueheng QIU Jinbo...