SAN DIEGO — Roughly two-thirds of new chlamydia cases are being missed because of lax attention to screening guidelines by primary care physicians, obstetrician-gynecologists, and pediatricians, Dr. David E. Soper said at the annual meeting of the American College of Obstetricians and Gynecologists.
Chlamydia remains the most common sexually transmitted disease in the United States, with more than 976,000 new cases reported each year and an estimated 2 million cases going undiagnosed.
Women with undetected, untreated chlamydia face at least a 40% chance of being diagnosed with pelvic inflammatory disease (PID). “We're not screening like we really should, despite highly sensitive and very specific tests,” said Dr. Soper, professor of ob.gyn. at the Medical University of South Carolina, Charleston.
“I think collectively we're not doing a good job.”
Screening is particularly lacking for adolescents, who have the highest rates of chlamydia in the United States, and for privately insured women, he said during a press conference highlighting the issue.
Among women covered by Medicare, “modest gains” were made in 2006, with almost half of sexually active women aged 25 and younger being screened annually, as recommended by ACOG, the Centers for Disease Control and Prevention, and the U.S. Preventive Services Task Force.
Far fewer commercially insured women—“maybe 35% or 40%”—are receiving annual screening, according to data from State of Health Care Quality reports, he said.
“We'd like to see these rates go up to the 90% range,” Dr. Soper said.
Besides the annual screening of women aged 25 years and younger, screening is recommended for other women in high-risk groups as well, including those with new or multiple sexual partners and those with a prior history of sexually transmitted disease.
Routine screening of men is not currently recommended, although it may be considered in areas of high prevalence.
Currently, the prevalence of chlamydia ranges from 4% to 12%; recent testing of asymptomatic female Army recruits in the San Francisco area identified 9% with the infection.
If women were screened as recommended and treated, if infected, with a single dose of 1 g of azithromycin, an estimated 140,000 cases of PID a year could be prevented, Dr. Soper said.
This has the potential of saving $45 in health costs for every woman screened, making chlamydia screening one of the most effective but underutilized preventive health services targeted by the CDC and the Agency for Healthcare Research and Quality.
Treatment of PID and its consequences—including infertility, ectopic pregnancy, and chronic pelvic pain—now exceeds $3.5 billion a year.
Dr. Laura E. Riley, medical director of labor and delivery at Massachusetts General Hospital, Boston, called the sequelae of untreated chlamydia “devastating,” not only for women, but for their exposed infants.
Babies born to mothers with untreated chlamydia have a 25%–30% chance of developing chlamydial conjunctivitis, and up to a 40% chance of developing chlamydial pneumonia.
During pregnancy, a single dose of azithromycin can be used to treat chlamydia, but women should be retested for proof of cure after 3 weeks to ensure that the disease has cleared. Infants can be treated with erythromycin; however, many require retreatment, she said.
Both physicians stressed the efficacy of the nucleic acid amplification testing (NAAT) method and noted that urine samples, as well as endocervical or vaginal swabs, may be used to make the diagnosis.
They urged physicians not only to screen for chlamydia, but to regularly talk with patients about STD prevention strategies, including abstinence, monogamy, or use of a condom during every sexual contact.