A 45-year-old business executive is admitted to the telemetry unit. He tells the nurse that he travels a lot for business and has recently returned from a trip to Mexico. During your initial...

A 45-year-old business executive is admitted to the telemetry unit. He tells the nurse that he travels a lot for business and has recently returned from a trip to Mexico. During your initial assessment, he tells you that he is not married, and he relates stories about some of the women he has met and dated on his many trips. His history includes persistent abdominal pain, nausea with occasional vomiting, fatigue, and decreased appetite.Initial vital signs and laboratory results include the following:

What is the most likely diagnosis, and what precautions should the nurse take while caring for this patient?