Final answer:
For the treatment of pseudomembranous enterocolitis in a patient over the age of 60 with specific symptoms, Metronidazole is the preferred antibiotic. Vancomycin is an alternative option for patients who do not respond to Metronidazole or have certain contraindications.
Step-by-step explanation:
The subject of this question is Medicine, and it refers to the treatment of pseudomembranous enterocolitis, which is commonly caused by the bacterium Clostridium difficile (C. difficile). The clinical focus provided indicates that in cases of antibiotic-associated pseudomembranous colitis, it is recommended to first stop the use of antibiotics, and if the diagnosis of C. difficile infection is confirmed, Metronidazole is the preferred treatment. Furthermore, Vancomycin is an alternative treatment that can be considered in certain circumstances, such as when a patient is either allergic to or has not responded to Metronidazole therapy, or if they meet other specific criteria like being under the age of 10, pregnant, or presenting with severe disease.
Based on the clinical details presented (an individual over the age of 60, a temperature of 38.7C, and a white blood cell count of 19.8K), the recommended antibiotic for treating pseudomembranous enterocolitis caused by C. difficile would typically be Metronidazole, unless the patient has specific contraindications or has already had an insufficient response to this treatment.