Final answer:
The next best step in the management of this patient is Abdominal and pelvic ultrasound. The patient's symptoms, including abdominal pain, tenderness, decreased bowel sounds, and right-sided predominance, suggest the possibility of appendicitis or pelvic inflammatory disease (PID). Ultrasound can be used to evaluate the appendix for signs of inflammation or fluid collection, as well as assess the uterus and adnexa for any abnormalities associated with PID.
Step-by-step explanation:
The next best step in the management of this patient is Abdominal and pelvic ultrasound. The patient's symptoms, including abdominal pain, tenderness, decreased bowel sounds, and right-sided predominance, along with her history of fever and exposure to a child with diarrhea, suggest the possibility of appendicitis or pelvic inflammatory disease (PID). Ultrasound can be used to evaluate the appendix for signs of inflammation or fluid collection, as well as assess the uterus and adnexa for any abnormalities associated with PID.