What is the treatment for a patient with a Chlamydia (Nucleic Acid Amplification) positive result?

Treatment for Chlamydia NAA Positive

For a patient with a positive Chlamydia nucleic acid amplification test, treat immediately with either azithromycin 1 g orally as a single dose OR doxycycline 100 mg orally twice daily for 7 days. 1, 2

First-Line Treatment Regimens

The two recommended first-line options are equally effective:

• Azithromycin 1 g orally as a single dose - Preferred when compliance is uncertain or follow-up is unpredictable, with 97% microbial cure rate 1, 3
• Doxycycline 100 mg orally twice daily for 7 days - Equally effective with 98% cure rate, less expensive than azithromycin, but requires multi-day dosing 1, 3

Dispense medications on-site and directly observe the first dose to maximize compliance. 1

Alternative Regimens (When First-Line Options Contraindicated)

If azithromycin or doxycycline cannot be used:

• Erythromycin base 500 mg orally four times daily for 7 days 1
• Erythromycin ethylsuccinate 800 mg orally four times daily for 7 days 1
• Ofloxacin 300 mg orally twice daily for 7 days 1
• Levofloxacin 500 mg orally once daily for 7 days 1

Note that erythromycin has higher rates of gastrointestinal side effects that reduce compliance, making it less effective in practice. 1 Quinolones are more expensive and offer no dosing advantage over doxycycline. 1

Critical Management Steps Beyond Antibiotics

Sexual Abstinence Requirements

Patients must abstain from all sexual intercourse for 7 days after single-dose therapy OR until completion of a 7-day regimen AND until all sex partners have completed treatment. 1, 3 This prevents transmission and reinfection.

Partner Management (Essential to Prevent Reinfection)

All sex partners from the preceding 60 days must be evaluated, tested, and treated. 1, 3 If the patient had symptom onset, treat partners who had contact within 60 days before symptoms began. 1 If asymptomatic, treat partners from the 60 days before diagnosis. 1

Treat the most recent sex partner even if contact occurred outside these time windows. 1

Consider expedited partner therapy (providing medication directly to the patient to give to partners) if partners are unlikely to seek medical care. 3

Special Population: Pregnancy

In pregnant patients, use azithromycin 1 g orally as a single dose (preferred) OR amoxicillin 500 mg orally three times daily for 7 days. 3, 4

Doxycycline, ofloxacin, and levofloxacin are absolutely contraindicated in pregnancy. 1, 3, 5

Pregnant women require a test-of-cure 3 weeks after treatment completion due to potential maternal and neonatal complications. 3

Follow-Up and Retesting Strategy

Test-of-Cure (Generally NOT Recommended)

Do not perform test-of-cure in non-pregnant patients treated with azithromycin or doxycycline unless compliance is questionable, symptoms persist, or reinfection is suspected. 1, 3

If test-of-cure is needed, wait at least 3 weeks after treatment completion to avoid false-positive results from dead organisms. 1, 3

Retesting for Reinfection (Strongly Recommended)

Retest all women approximately 3 months after treatment, regardless of whether partners were treated. 1, 3 This is distinct from test-of-cure and addresses the high reinfection rate.

Also retest women at their next clinical visit within 3-12 months after treatment. 1 Repeat infections carry elevated risk for pelvic inflammatory disease and infertility compared to initial infections. 1, 3

Most recurrent positive tests (84-92%) represent reinfection from untreated or new partners, not treatment failure. 3 True treatment failure rates are extremely low: 0-3% in males and 0-8% in females. 3

Common Clinical Pitfalls to Avoid

• Delaying treatment while waiting for test results - Treat immediately upon positive NAAT result 1
• Failing to treat sex partners - This is the single most important factor in preventing reinfection 3
• Allowing sexual activity before partner treatment is complete - Both patient and all partners must complete treatment before resuming intercourse 3
• Testing too early after treatment - Wait at least 3 weeks to avoid false-positives from dead organisms 1, 3
• Not retesting women at 3 months - This is a high-risk period for reinfection and elevated PID risk 3
• Assuming treatment failure when reinfection is more likely - Most recurrences are reinfections, not antibiotic resistance 3

Special Considerations for Children

For children weighing <45 kg: Erythromycin base or ethylsuccinate 50 mg/kg/day orally divided into four doses daily for 14 days 1

For children weighing >45 kg but aged <8 years: Azithromycin 1 g orally as a single dose 1

For children aged >8 years: Azithromycin 1 g orally as a single dose OR doxycycline 100 mg orally twice daily for 7 days 1