Male Urethritis (Gonococcal and Chlamydial Coinfection)
A 22-year-old man reports two days of dysuria and mucopurulent urethral discharge after unprotected intercourse with a new partner. He is afebrile at 37.0 °C with no testicular tenderness or skin lesions. Gram stain of the discharge shows numerous neutrophils with intracellular gram-negative diplococci. Nucleic acid amplification testing is pending. Which of the following is the most appropriate empirical treatment?
- A.Intramuscular ceftriaxone plus oral doxycyclineCorrect
- B.Oral azithromycin as a single dose
- C.Intramuscular ceftriaxone as a single dose
- D.Oral nitrofurantoin for seven days
Explanation
Acute urethritis in a young sexually active man is caused predominantly by Neisseria gonorrhoeae and Chlamydia trachomatis, and coinfection is common enough that empirical therapy must cover both organisms rather than only the one suggested by the Gram stain. Intracellular gram-negative diplococci confirm gonorrhoea but do not exclude concurrent chlamydia, which is present in a substantial minority of gonococcal urethritis cases. CDC guidance is a single intramuscular dose of ceftriaxone 500 mg for uncomplicated urogenital gonorrhoea, increased to 1 g for people weighing 150 kg or more, plus doxycycline 100 mg twice daily for 7 days whenever chlamydia has not been excluded. Doxycycline replaced azithromycin as the preferred chlamydia agent because of superior efficacy, particularly for rectal infection, and azithromycin is no longer given as a routine companion drug for gonorrhoea because of rising macrolide resistance. Azithromycin 1 g remains an alternative for chlamydia when adherence to a 7-day course is doubtful or in pregnancy, but it never covers gonorrhoea reliably. Ceftriaxone as a single agent leaves chlamydia untreated and risks progression to epididymitis and onward transmission. Nitrofurantoin concentrates in urine and treats cystitis but has no useful activity against these fastidious and intracellular pathogens. Management also includes partner notification and treatment, testing for HIV and syphilis, and abstinence until therapy is complete. Persistent symptoms after correct therapy should raise suspicion of Mycoplasma genitalium or Trichomonas vaginalis.
Why each option
- A.
- Correct. Dual therapy with ceftriaxone plus doxycycline covers both gonorrhoea and the frequently coexisting chlamydial infection.
- B.
- Azithromycin alone leaves gonorrhoea untreated and is no longer preferred for chlamydia because of reduced efficacy and macrolide resistance.
- C.
- Ceftriaxone alone treats gonorrhoea but not the coexisting chlamydia present in a large minority of these patients.
- D.
- Nitrofurantoin is a urinary agent for cystitis and has no useful activity against gonorrhoea or chlamydia.
Reference: CDC Sexually Transmitted Infections Treatment Guidelines, 2021, Gonococcal Infections Among Adolescents and Adults (current as of 2026)
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