A 42-year-old man with HIV who has both insertive and receptive anal sex with men presents for routine follow-up and screening for sexually transmitted infections. He currently has no anogenital symptoms. Nucleic acid amplification tests (NAATs) are performed for Chlamydia trachomatis and Neisseria gonorrhoeae on a urine sample, pharyngeal swab, and anal swab. One day later the rectal NAAT was positive for N. gonorrhoeae, but all other tests were negative. He weighs 153 kg.