[Expert Solution]: A 83-year-old man has a medical history of…

A 83-year-old man has a medical history of diabetes, hypertension, dementia, and neurogenic bladder requiring the long-term use of urethral indwelling catheters. Last month he was admitted to an SNF because of his worsening dementia. The patient has a history of UTIs (usually once or twice a year), with the most recent UTI approximately 6 weeks ago and had his catheter replaced at that time. In the ED, he was started on cefepime 1000 mg IV q 12 hours (reduced for creatine clearance of 35 ml/min). Currently, his vital signs are Tmax 98.6°F (37°C), blood pressure 135/85 mm Hg, heart rate 75 beats/minute, and respiratory rate 18 breaths/minute. WBC is 12.5 and SCr is 1.2 (baseline 0.8) mg/dL and creatinine clearance remains unchanged. Urinalysis reveals WBC greater than 182 per high-power field, large leukocyte esterase, and positive nitrite. He only has complaints of pain caused by a pressure ulcer on his right back. For the last episode (about 4 weeks ago) he received Nitrofurantoin for P. mirabilis and a current susceptibility report from the urine culture is below. Ampicillin, Ampicillin + Sulbactam, Cefazolin, Ciprofloxacin, Meropenem, Gentamicin, Nitrofurantoin, Trimethoprim Sulfamethoxazole, Piperacillin and tazobactam, and levofloxacin are sensitive to Ecoli. Which one of the following choices is best for this patient at this time? De-escalate therapy to cefazolin 1000 mg IV q 12 hours Maintain regimen as cefepime 1000 mg IV every 12 hours Add gentamicin 3 mg/kg IV every 24 hours to cefepime