Chlamydia Screening

Chlamydia Screening: Providing Enormous Value to Patients & Society

Physicians call them “heartbreakers” – women who were infected with Chlamydia when they were young, but never knew they had a problem until they wanted to start a family and discovered they were infertile, or had a tubal pregnancy, or developed chronic and debilitating pelvic pain, or were diagnosed with cervical cancer.

Chlamydia is an insidious bacterial disease. Affecting one in 10 sexually active adolescent girls, it is the most common sexually transmitted disease in the US . Most young women who become infected never experience symptoms that would prompt them to see a doctor. Left untreated, up to 40% of infected women develop pelvic inflammatory disease, and of these cases, 20% become infertile, 18% develop chronic pain, and 9% have a life-threatening tubal pregnancy. Chlamydia infections are a significant problem among minority women, and can predispose both women and men to HIV infections. Pregnant women who are infected at the time they give birth can pass the infection to their newborns, which develop eye infections and pneumonia.

Aside from the emotional toll that these conditions extract from women, men, and couples, the medical costs of untreated Chlamydia infections are staggering: $3.5 billion a year. The Centers for Disease Control and Prevention has shown that national screening programs, implemented in the 1980s and conducted primarily through public health clinics and family planning centers, can reduce the number of annual cases and both the emotional and economic burden. Experts estimate that for every dollar spent on screening, $12 is saved on the costs of treating Chlamydia complications.

Simple to Diagnose, But Most Cases Never Detected

Dr. Richard Steece, science advisor for the Association of Public Health Laboratories and National Chlamydia Laboratory Coordinator for the CDC's Infertility Prevention Project, says Chlamydia is easy to diagnose and simple to treat with antibiotics when caught early. However, the vast majority of infections, which occur in women ages 15-24 and in men ages 20-24, are missed. The CDC estimates that 3 million people will be infected with Chlamydia this year; yet only about 800,000 cases are expected to be diagnosed by public health clinics and doctors offices.

“The good news is that the diagnostic tests are excellent and the screening programs do work very effectively,” Steece says. “The system works when the money is put into it.”

The technology for diagnosing Chlamydia has improved dramatically over the past decade. The state of the art in diagnostic tests takes advantage of progress made in understanding DNA and its messenger component RNA. Older tests for Chlamydia required that medical staff take swabs of a woman's cervix or of a man's urethra, and then laboratories had to culture the swabs to determine whether the bacteria were present. This process could take days to learn results. About a decade ago, scientists developed a way of targeting a segment of the bacteria's RNA to determine, in about a day, the presence of Chlamydia in a cervical or urethral swab.

More recently, Chlamydia testing has advanced with tests that amplify tiny bits of the bacteria's DNA present in a sample of urine. This is known as the nucleic acid amplification test, or NAT. It is based on the same type of technology used in genetic fingerprinting, in which an otherwise invisible fragment of DNA is copied millions of times until it can be identified. NAT is more expensive than previous technologies, but it is far superior in its ability to detect Chlamydia – in more than 90% of cases compared with about 50% to 70% of cases using older tests.

Steece says NAT saves money in the long term because it catches more cases of Chlamydia up front, thus preventing many more cases of costly complications. Also, since NAT utilizes a urine sample, women and men are more likely to volunteer for screening. Home tests, in which a person takes a urine sample and mails it to a laboratory, will provide greater privacy for those reluctant to be screened.

“Many interesting new technologies should be coming out in the next year or two,” Steece says. “We could be collecting specimens from the home setting, or we could be targeting certain high risk groups, or providing tests that are specific for Chlamydia infections in the rectal, ocular and respiratory tracts. In the future we could have real-time tests that can provide results within an hour.”

Ensuring Patient Access

Many hurdles remain that limit patient access to these important tests. One is that many laboratories still use older non-amplified types of tests. Unless patients and physicians insist on NAT, Steece says they get whatever test a laboratory is using. Screening programs also are under-funded. The lack of federal dollars for public health laboratories means fewer people can be screened and that laboratories must operate with fewer technicians.

According to a new report by The Lewin Group, Medicare reimbursement for new clinical laboratory tests is “archaic, impractical and severely flawed” and discourages the use and development of new tests. It takes an act of Congress for Medicare patients to gain access to specific screening tests. In addition, the authors found that Medicare often pays the same or less for a new test than an existing test, despite the fact that the new test may offer greater benefits to patients and physicians.

While the clinical and economic value of Chlamydia testing has been well-documented, certain local Medicare carriers have developed payment rates that do not reflect this value, creating disincentives for its utilization and encouraging the use of inferior technology. While the use of less sensitive technology for the detection of Chlamydia is generally cheaper initially, it is likely to lead to a significant increase in downstream system costs for the treatment of pelvic inflammatory disease and other complications associated with undetected Chlamydia infection.

Sources:

“The Value of Diagnostics: Innovation, Adoption, and Diffusion into Health Care.” The Lewin Group, 2005.

MMWR , Oct. 18, 2002, Vol 51, No. RR-15

JAMA , May 12, 2004, Vol. 291, No. 18