A 27-year-old man is being evaluated for the new onset of discomfort along the posterolateral aspect of his left testicle that has gradually increased over the past 48 hours. He endorses mild dysuria over the past 1 week. In the last 6 months, he reports vaginal insertive intercourse with 4 partners. They intermittently use condoms. He denies fever, chills, or urethral discharge.