A physician was treating one young female and one elderly patient for urinary tract infections caused by the same type of bacterium.

A physician was treating one young female and one elderly patient for urinary tract infections caused by the same type of bacterium.  Although the patients had similar body dimensions and weight, the physician gave a smaller dose of drug to the older patient.  What was the physician’s rationale for this decision?  In addition, the younger patient was not an admitted hospital patient but the elderly woman was.  The physician ran more tests on the elderly woman and she was frequently checked to make sure she didn’t develop a fever.  Why was this?  How do you think the elderly person developed the Urinary Tract Infection?