Case of the Month - July 2019
A 65 year old man was hospitalized after being found at home, delirious, covered in urine and feces, and with abrasions, bruises, and cuts. In the E.R. he was hypothermic and hypotensive, and intubated for acute respiratory failure due to pneumonia. He was treated with vancomycin and piperacillin-tazobactam in the I.C.U., but had a long hospital course due to multiple complications. Over the next two weeks he became steadily worse, and was treated with increasingly broad-spectrum antibiotics. On hospital day #18, E. coli grew in urine and blood culturess. The culture report from the Microbiology Laboratory is in Figure 1.
What is the mechanism of resistance?