Which laboratory tests are recommended for confirming a diagnosis of PID in women presenting with lower abdominal pain?

Recommended laboratory tests for confirming a diagnosis of pelvic inflammatory disease (PID) in women presenting with lower abdominal pain include:

• Screening for sexually transmitted infections (STIs), particularly Chlamydia trachomatis and Neisseria gonorrhoeae, using vaginal or endocervical swabs before starting antibiotic treatment, to aid accurate diagnosis and guide management.
• Empirical antibiotic treatment should not be delayed while awaiting test results, but STI screening is advised ideally before treatment initiation.
• Additional laboratory tests may include vaginal swabs for microbiological culture and sensitivity to tailor antibiotic therapy if needed.
• Pregnancy testing is essential to exclude ectopic pregnancy, which can present similarly.

These tests are part of the initial assessment and management strategy in primary care or specialist sexual health services, with urgent hospital admission considered if complications or severe symptoms are present.

Note that no single laboratory test definitively confirms PID; diagnosis is primarily clinical supported by laboratory evidence of infection.

Follow-up testing, including test of cure for gonorrhoea and chlamydia, is recommended after treatment completion.

Additional investigations such as inflammatory markers or imaging are not routinely recommended for diagnosis but may be used if complications are suspected.

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