下呼吸道感染中非发酵菌耐药性分析

目的：探讨非发酵菌所致下呼吸道感染的临床特点及细菌耐药性。方法：分析天津市区10所医院呼吸科收治的494例非发酵菌致下呼吸道感染资料。结果：所收治的494例中．社区获得性肺炎占多数。高龄、重症基础疾病、长期应用抗生素或激素、气管插管及导管留置时间过长是非发酵菌导致下呼吸道感染的危险因素。其临床表现缺乏特异性。检出非发酵菌各属细菌的比例依次为不动杆菌属(57．3％)、铜绿假单胞菌(33．5％)、嗜麦芽窄食单胞菌(4．6％)、其他假单胞菌(2．4％)和其他(2．2％)。药敏结果显示非发酵菌严重耐药，亚胺培南耐药性最低。非发酵菌对第三代头孢菌素及氨曲南、氨苄西林高度耐药。加用β内酰胺酶抑制剂的第三代头孢菌素的耐药率大大低于未加用者。结论：非发酵菌致下呼吸道感染临床表现无特异性．治疗时应根据药敏结果选择应用抗生素。

Antimicrobial resistance of non-fermentative bacilli from patients with lower respiratory tract infections

Objective: To investigate the clinical manifestations and antimicrobial resistance of non-fermentative gram-negative bacilli isolated from patients with lower respiratory tract infections. Methods: Clinical data of 494 patients with lower respiratory tract infections caused by non-fermentative bacilli in department of respiratory diseases in 10 Tianjin hospitals during 2000-2002 and bacterial resistance of these organisms were reviewed. Results: Nearly half of these 494 cases were community-acquired pneumonia. Risk factors for non-fermentative bacillus infections included advanced age, severe underlying diseases, long term use of broad-spectrum antibiotics or adrenal cortical hormone, endotracheal intubation and long term indwelling catheter. It's clinical features were lack of specificity. Non-fermentative gram-negative bacillus isolates consisted of 57. 3% of Acinetobacter spp. , 33. 5% of Pseudomonas aeruginosa, 4. 6% of Stenotrophomonas maltophilia , 2. 4% of other Pseudomonas spp. and 2. 2% of others. The antimicrobial susceptibility testing results showed that non-fermentative bacilli were highly resistant to commonly used antimicrobials including ampicillin, third generation cephalosporins and aztreonam. The resistance rate to imipenem was the lowest among the tested antibiotics, while the resistance rate cefoperazone-sulbactam was significantly lower than cefopera zone alone. Conclusions: The clinical features of lower respiratory tract infections caused by non-fermentative bacilli are lack of specificity. Antibiotics should be chosen according to antibiotic susceptibility testing results.