Chlamydia infection can cause serious clinical manifestations
The 15 serotypes of C trachomatis are grouped into 3 categories according to clinical manifestations:
- Serotypes A, B, Ba, and C cause endemic trachoma, characterized by bilateral irritation of the eyelids that progresses to eyelid thickening and scarring, eventually leading to corneal abrasion and blindness.
- Serotypes D–K manifest as conjunctivitis and pneumonia in newborns, proctitis in men (especially in men who have sex with men), and genitourinary infections in women. Reactive arthritis and inclusion conjunctivitis also can occur with D–K serotypes.
- Serotypes L1–L3 cause lymphogranuloma venereum.
About 70% of women with chlamydia infection are asymptomatic. Those who have symptoms often present with endocervicitis or acute urethral syndrome (acute urethritis). Manifestations of these 2 conditions include a frothy yellow-green vaginal and/or urethral discharge, dysuria, and frequency. Women who engage in rectal intercourse also may notice a purulent discharge from the anus. Untreated, C trachomatis organisms may ascend the reproductive tract, causing both endometritis and pelvic inflammatory disease (PID).
While a single episode of PID increases tubal infertility risk by 10%, a second episode increases the risk by 40%.3 Over time, recurrent and/or chronic PID causes scarring and adhesion formation, which may result in chronic pelvic pain. In addition, chronic infection is the single most important risk factor for ectopic pregnancy. Finally, chlamydia infection is a risk factor for Fitz-Hugh-Cutis syndrome (perihepatitis). In this condition, organisms ascend from the site of pelvic infection along the pericolic gutter to ultimately infect the liver capsule.
Specific complications in pregnancy
Chlamydia infection in pregnant women is associated with preterm delivery and preterm premature rupture of membranes. Infants born to mothers with untreated chlamydia infection are at risk for pneumonia, conjunctivitis, and even perinatal death.2 Acquisition of infection occurs at the time of delivery rather than in the antepartum period.
The significant morbidity associated with chlamydia infection underscores the importance of regular screening, especially in pregnant women. The current United States Preventive Service Task Force guidelines recommend annual screening of all sexually active women who are 24 years of age or younger, as well as of older, high-risk women.
The CDC recommends routine screening of all pregnant women for chlamydia at the first prenatal visit. Repeat screening is recommended in the third trimester for all pregnant women younger than 25 years, those at increased risk, and those infected within the past 3 to 6 months or during the first trimester. Those who test positive should be retested 3 weeks after completion of treatment.1
Chlamydia screening strategies
Historically, a chlamydia diagnosis was made by isolating the organisms in tissue culture. In the 1990s, however, that extremely time-consuming and resource-intensive procedure was replaced by nucleic acid amplification testing (NAAT).
NAAT methodology. NAAT is the gold standard for diagnosing C trachomatis infection; this methodology utilizes various assays, including polymerase chain reaction, ligase chain reaction, and transcription-mediated amplification.
Continue to: Compared with previous culture and antigen detection techniques...