Chlamydia

Chlamydia, or more specifically a chlamydia infection, is a sexually transmitted infection caused by the bacterium Chlamydia trachomatis. Most people who are infected have no symptoms. When symptoms do appear, they may occur only several weeks after infection. The incubation period between exposure and being able to infect others is thought to be from two to six weeks.

Signs and Symptoms

Genital Disease

In women, chlamydia often presents with no symptoms in approximately 70% of cases. When symptoms occur, they may include abnormal vaginal bleeding or discharge, abdominal pain, painful sexual intercourse, fever, and painful urination. If untreated, it can lead to pelvic inflammatory disease (PID), causing scarring and serious complications such as chronic pelvic pain, infertility, and ectopic pregnancy.

In men, symptoms occur in about 50% of cases and may include painful urination, unusual discharge from the penis, testicular pain or swelling, and fever. Untreated chlamydia can spread to the testicles, causing epididymitis, which can lead to sterility if not treated.

Eye Disease

Trachoma, a chronic conjunctivitis caused by Chlamydia trachomatis, can lead to blindness. It is spread through personal contact, shared towels, and eye-seeking flies. Symptoms of trachoma include mucopurulent ocular discharge, irritation, redness, and lid swelling.

Joints

Chlamydia may cause reactive arthritis, especially in young men. This condition includes symptoms of arthritis, conjunctivitis, and urethral inflammation. Approximately 15,000 men in the U.S. develop reactive arthritis due to chlamydia annually.

Infants

Infants born to mothers with chlamydia can be affected by the disease, leading to spontaneous abortion, premature birth, conjunctivitis, and pneumonia. Conjunctivitis typically occurs one week after birth.

Transmission

Chlamydia can be transmitted through vaginal, anal, oral, or manual sex as well as direct contact with infected tissue. It can also be passed from an infected mother to her baby during childbirth. The probability of becoming infected is proportionate to the exposure level of the bacteria.

Pathophysiology

Chlamydia bacteria can establish long-term associations with host cells. When the host cell is starved of nutrients, the bacteria enter a persistent growth state, stopping cell division and increasing in size. Persistent organisms remain viable and can return to a normal growth state once conditions improve. This persistence may be relevant in causing chronic chlamydial diseases.

Diagnosis

Diagnosis has significantly improved with nucleic acid amplification tests (NAAT) such as PCR, TMA, and SDA. These tests can be performed on swab specimens from the cervix, urethra, or on voided urine. NAATs have a sensitivity of approximately 90% and specificity of 99%.

Prevention

Prevention measures include not having sex, using condoms, or having sex with only one person who is not infected. Regular screening is recommended for sexually active women under 25 and those at risk of infection. Pregnant women should also be screened.

Treatment

Chlamydia can be effectively treated with antibiotics such as azithromycin, doxycycline, erythromycin, levofloxacin, or ofloxacin. In men, doxycycline is probably more effective than azithromycin, while erythromycin or amoxicillin is preferred during pregnancy. Sexual partners should be treated, and infected individuals should avoid sex for seven days and until symptom-free. Retesting is recommended after three months to check for reinfection.

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Self-assessment MCQs (single best answer)

What bacterium causes a chlamydia infection?

What percentage of women with chlamydia show no symptoms?

Which of the following is a potential complication of untreated chlamydia in women?

Which test is known for high sensitivity and specificity in diagnosing chlamydia?

Which antibiotic is recommended for treating chlamydia in pregnant women?

What condition can develop in men as a complication of untreated chlamydia?

Which symptom is NOT typically associated with genital chlamydia in men?

What is the recommended action for individuals infected with chlamydia regarding sexual activity?

Which of the following is a common sign of trachoma, the eye disease caused by _Chlamydia trachomatis_?

Which group is recommended to undergo regular screening for chlamydia?