Genital tract chlamydia infections are one of the most frequently reported sexually transmitted infections.
Many infected individuals are asymptomatic.
In women, there may be cervical inflammation or yellow, cloudy discharge from the cervical os, resulting in vaginal discharge.
In men, there may be a discharge from the penis.
Nonculture techniques such as the nucleic acid amplification test are available and are the preferred diagnostic method. Tests in men are performed on urine or urethral samples. Tests in women are performed on urine, cervical, or vaginal samples, which are either clinician- or self-collected.
Untreated or inadequately treated patients are at increased risk for ascending infection and further complications. Patients also risk spreading the infection to sexual partners and from mother-to-child during labor and delivery.
Urogenital chlamydia infection is a common sexually transmitted infection (STI; also known as sexually transmitted disease, STD) worldwide. The causative organism is Chlamydia trachomatis. Infection is usually asymptomatic in both men and women.
In women, chlamydia infection tends to occur in the endocervical canal. Some women who have uncomplicated cervical chlamydia infection already have subclinical upper reproductive tract infections upon diagnosis. Symptoms may include intermenstrual or postcoital bleeding; an odorless, mucoid vaginal discharge; pelvic pain; or dysuria. In men, chlamydia infection can occur in the urethra, causing a penile discharge; or dysuria.
Untreated or inadequately treated chlamydia infections can lead to more serious problems such as pelvic inflammatory disease (PID), ectopic pregnancy, and infertility in women, epididymitis and prostatitis in men, and reactive arthritis in all patients. Infants born to women with untreated chlamydia are at risk of neonatal conjunctivitis and pneumonia.
History and exam
Key diagnostic factors
Other diagnostic factors
- cervical discharge
- friable cervix
- abnormal vaginal bleeding
- penile discharge
- vaginal discharge
- pelvic pain
- scrotal pain
- abdominal pain
- mucopurulent rectal discharge or tenesmus
- joint pain and swelling
- eye irritation
- age under 25 years, sexually active
- new sex partner or multiple sex partners
- sexual activity with infected partner
- condoms not used
- history of prior STI
- urban residence and low socioeconomic status
1st investigations to order
- nucleic acid amplification test (NAAT)
Investigations to consider
- direct immunofluorescence
- enzyme immunoassay
- nucleic acid hybridization tests
- cell culture
- rapid and point-of-care tests
confirmed or suspected
Matthew M. Hamill, MBChB, PhD, FRCP
Assistant Professor of Medicine
Johns Hopkins University School of Medicine
MMH receives royalties for contributing to UpToDate on Lymphogranuloma venereum and for Clinical Care Options. He has an honorarium from Roche Diagnostics for panel STI & HIV 2021 World Congress (virtual) and was a member of the 2021 Roche group on future of POCT for STI. He has also received consulting fees from GSK for the HSV vaccine.
Dr Matthew M. Hamill would like to gratefully acknowledge Dr Anne Rompalo and Dr Christopher K. Fairley, the previous contributors to this topic.
AR and CKF declare that they have no competing interests.
Kenneth Lin, MD
American Family Physician
Clinical Assistant Professor
GUSOM Medical Officer
US Preventive Services Task Force
KL declares that he has no competing interests.
Lars Jørgen Østergaard, MD, PhD, DMSc
Department of Infectious Diseases
Aarhus University Hospital
LJO has been funded by Pfizer to write a leaflet on Chlamydia infections.
- Lymphogranuloma venereum
- Gonorrhea infection
- Bacterial vaginosis
- Reducing sexually transmitted infections
- Screening for chlamydia and gonorrhea: recommendation statement
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