军团菌选择性分离培养基及其实用性比较研究

Compared research of selective culture media for Legionella and clinical practicability

目的探讨与改进嗜肺军团菌选择性分离培养基及其临床实用性评价。方法在BCYEα基础培养基中添加3种不同抗生素组合：CCCV、DGVP（含自配特种染料）和GVPC，以不含抗生素的BCYEα平板作对照，采用菌落计数法比较添加3种不同抗生素和染料的选择性分离平板对嗜肺军团菌生长的影响，同时比较3种选择性分离平板对空调冷凝塔水中嗜肺军团菌的分离率。结果在BCYEα＋DGVP和BCYEα＋GVPC平板上菌落计数（菌液稀释度在10^5～10^7之间）和BCYEα平板结果相类似，差异无统计学意义（P〉0．05）。在BCYEα＋CCCV平板上生长菌落数只有前3种平板的1／2，差异有统计学意义（P〈．05）。从9个中央空调冷凝塔水中分离嗜肺军团菌，用BCYEα＋DGVP和BCYEα＋GVPC平板分离出5株嗜肺军团菌，而BCYEα＋CCCV平板仅分离出2株，不加抗生素的BCYEα平板未分离出军团菌。结论常规用BCYEα＋CCCV平皿对杂菌有较强的抑制作用，但对嗜肺军团菌亦有一定抑制作用，因而在实际应用中降低了嗜肺军团菌的分离率；BCYEα＋DGVP和BCYEα＋GVPC平皿（自制）对嗜肺军团菌的抑制作用微弱，而对杂菌有较强的抑制作用，提高了嗜肺军团菌的分离率。

Objective To develop a selective isolation media which has a high isolation ratio for Legionella. Methods We compared the growth of Legionella pneumonia on BCYEα plate （with DGVP）, BCYEα（with GVPC） and BCYEα （with CCCV） by colony count and compared with BCYEα plate. The comparison of isolation ratio of Legionella pneumonia from air-conditions cooling water with 3 kinds of BCYEα plate containing different anti-reagents was performed. Results The results of colony count on BCYEα plate （with DGVP） and BCYEα（with GVPC） was identical with that on BCYEα plate at same concentration. But the result of colony count on BCYEα plate （with CCCV） was half of the former 2 kind,s of plate. 5 strains of Legionella pneumonia isolated from 9 central air-condition cooling water were used by BCYEα plate （with DGVP） and BCYEα （with GVPC）, while only 2 strains of Legionella pneumonia were isolated by BCYEα plate （with CCCV）. Legionella pneumonia wasn＇t detected by BCYEα plate. Conclusion BCYEα plate with antibiotics system of CCCV showed obvious suppression to Legionella pneumonia, and so that there was a low isolation ratio to Legionella pneumonia. But BCYEα plate with antibiotics system of DGVP and GVPC had a few suppression and showed a high isolatio ratio for Legionella pneumonia. Moreover, BCYEα plate with antibiotics system of DGVP and GVPC can effectively inhibit non Legionella and increase isolation ratio of Legionella. They should be the first selection media for Legionella from environment and clinical samples.