Tsuchimori N, Hayashi R, Shino A, Yamazaki T, Okonogi K
Pharmaceutical Research Laboratories III, Takeda Chemical Industries, Ltd., Osaka, Japan.
Infect Immun. 1994 Oct;62(10):4534-41. doi: 10.1128/iai.62.10.4534-4541.1994.
Mixed urinary tract infection was caused by simultaneous inoculation of 10(4) CFU each of Enterococcus faecalis TN2005 and Pseudomonas aeruginosa P9 into the bladders of CBA/J mice. Both organisms proliferated in the kidneys, and viable cell counts of E. faecalis TN2005 reached a peak level of 4.1 x 10(5) CFU per pair of kidneys within the first 24 h, while P. aeruginosa P9 counts increased more slowly. The number of P. aeruginosa P9 cells peaked at 8.3 x 10(6) CFU per pair of kidneys 5 days after infection. Five days after mixed infection, infiltration of neutrophils into the renal pelvis and renal medulla was observed. Immunohistochemical staining revealed the presence of E. faecalis antigen in the renal medulla. P. aeruginosa antigen was detected mainly in the renal pelvis 5 days after infection and in the renal medulla as well as the renal pelvis 14 days after infection. Mixed infection induced pyelonephritis within 5 days after mixed infection, while it was not observed until 14 days after infection with P. aeruginosa P9 alone. P. aeruginosa P9 inoculated together with E. faecalis TN2005 was more resistant to eradication from the kidneys by beta-lactam antibiotics than P. aeruginosa P9 inoculated alone. These results suggest that E. faecalis TN2005 invades the renal medulla first in mixed urinary tract infection and induces histological changes which lead to aggravation of the pyelonephritis caused by P. aeruginosa P9.
混合性尿路感染是通过将粪肠球菌TN2005和铜绿假单胞菌P9各10(4) CFU同时接种到CBA/J小鼠膀胱中引起的。两种细菌都在肾脏中增殖，粪肠球菌TN2005的活菌数在最初24小时内达到每对肾脏4.1 x 10(5) CFU的峰值水平，而铜绿假单胞菌P9的数量增加得较慢。感染后5天，铜绿假单胞菌P9细胞数量达到每对肾脏8.3 x 10(6) CFU的峰值。混合感染5天后，观察到中性粒细胞浸润肾盂和肾髓质。免疫组织化学染色显示肾髓质中存在粪肠球菌抗原。感染后5天，铜绿假单胞菌抗原主要在肾盂中检测到，感染后14天在肾髓质和肾盂中也检测到。混合感染在混合感染后5天内诱发肾盂肾炎，而单独感染铜绿假单胞菌P9直到感染后14天才观察到肾盂肾炎。与单独接种铜绿假单胞菌P9相比，与粪肠球菌TN2005一起接种的铜绿假单胞菌P9对β-内酰胺类抗生素从肾脏中清除的抵抗力更强。这些结果表明粪肠球菌TN2005在混合性尿路感染中首先侵入肾髓质，并诱导组织学变化，导致铜绿假单胞菌P9引起的肾盂肾炎加重。
