In a patient presenting with lower abdominal pain and fever, what is the next best step in evaluation?

In a patient presenting with lower abdominal pain and fever, the clinical suspicion often points towards an infection or inflammatory process, particularly in the context of pelvic inflammatory disease (PID). An endocervical culture is a critical diagnostic tool in this situation because it allows for the detection of sexually transmitted infections such as chlamydia or gonorrhea, which are common causes of PID.

The endocervical culture helps confirm the presence of these pathogens, leading to appropriate antibiotic therapy. Given that PID can cause significant morbidity if left untreated, identifying the causative agents promptly is essential for effective management.

While other options like an abdominal X-ray might be useful in different contexts (for example, to check for perforated viscus or obstruction), it would not specifically address the likely underlying infectious process suggested by the combination of lower abdominal pain and fever. Similarly, laparoscopy, while useful for direct visualization in cases of suspected acute abdomen, is more invasive and typically reserved for cases where diagnosis remains unclear after less invasive evaluations. A hysterosalpingogram is primarily used to assess patency of the fallopian tubes and is not indicated for immediate evaluation in acute abdominal pain and fever.

Thus, focusing on the endocervical culture as the next best step