Fast Five Quiz: Sexually Transmitted Infections

Michael Stuart Bronze, MD


February 28, 2022

According to updated guidelines from the United States Preventive Services Task Force (USPSTF), chlamydia screening is recommended for all sexually active women aged 24 years or younger and for women aged 25 years or older who are at increased risk for infection. Factors that increase risk include:

  • A new sex partner

  • More than one sex partner

  • A sex partner with concurrent partners

  • A sex partner who has an STI

  • Inconsistent condom use when not in a mutually monogamous relationship

  • Previous or coexisting STI

Chlamydia trachomatis is a sexually transmitted microorganism that is responsible for a wide spectrum of diseases, including cervicitis, salpingitis, endometritis, urethritis, epididymitis, conjunctivitis, and neonatal pneumonia. In chlamydial infection, unlike gonorrhea, most men and women who are infected are asymptomatic; thus, diagnosis is delayed until a positive screening result is obtained or a symptomatic partner discovered.

Endocervical, urethral, rectal, or oropharyngeal specimens should be obtained and assayed for C trachomatis infection in both men and women based on the patient's sexual practices obtained by history. A voided urine sample, whether midstream or first-void, effectively captures the chlamydial organism for nucleic acid amplification testing (NAAT). NAATs are the most sensitive tests for these specimens and are therefore recommended for detecting C trachomatis infection. Cultures are difficult to obtain; many false-negative results are returned. They are also expensive to perform because of the expertise and laboratory resources required. In addition, they are unsuitable for large numbers of patients.

The latest CDC guidelines recommend doxycycline (100 mg orally twice daily for 7 days) as first-line treatment for chlamydia. Alternative regimens include azithromycin (1 g orally in a single dose) or levofloxacin (500 mg orally once daily for 7 days).

Learn more about chlamydia.


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