Cervical Cancer Screening for Women Who Attend STD Clinics or Have a History of STDs
Women with a history of STDs might be at increased risk for cervical cancer, and women attending STD clinics might have other risk factors that place them at even greater risk. Prevalence studies indicate that precursor lesions for cervical cancer occur approximately five times more frequently among women attending STD clinics than among women attending family planning clinics. Cervical cancer screening using the Pap test is an effective, low-cost screening test for preventing invasive cervical cancer. Recommendations for cervical cancer screening intervals vary in the United States, but the American Cancer Society and American College of Obstetricians and Gynecologists guidelines recommend annual screening for women aged 21--30 years and then every 2--3 years for women aged ≥30 years if three consecutive annual Pap tests are negative.[197,198]
During the appointment in which a pelvic examination for STD screening is performed, the health-care provider should inquire about the result of the patient's most recent Pap test and discuss the following information with the patient:
the purpose and importance of a Pap test;
the need for regularly scheduled Pap tests between aged 21--65 years;
whether a Pap test will be obtained during this clinic visit; and
if a Pap test will NOT be obtained during this examination, the names of local providers or referral clinics that can perform Pap tests and adequately follow up results if indicated.
If a woman has not had a Pap test during the previous 12 months, a Pap test may be obtained as part of the routine pelvic examination. Health-care providers should be aware that many women frequently equate having a pelvic examination with having a Pap test; they believe that a Pap test was taken when they actually received only a pelvic examination. They might, therefore, over report having had a recent Pap test. Therefore, in STD clinics, having a protocol for conducting cervical cancer screening should be highly encouraged and obtaining a Pap test strongly considered during the routine clinical evaluation of women who do not have clinical-record documentation of a normal Pap test within the preceding 12 months.
A woman might benefit from receiving printed information concerning Pap tests and a report containing a statement that a Pap test was obtained during her clinic visit. If possible, a copy of the Pap test result should be provided to the patient for her records when it becomes available.
STD clinics offering cervical cancer screening are encouraged to use cytopathology laboratories that report results by using the Bethesda System of classification. If the results of the Pap test are abnormal, follow-up care should be provided according to the ASCCP Consensus Guidelines for Management of Abnormal Cervical Cytology, or information regarding follow-up care is available at http//www.asccp.org. If resources in STD clinics do not allow follow-up of abnormal results, protocols for referral of women needing follow-up and case management should be in place. Pap tests indicating low- or high-grade SIL should always include referral to a clinician who can perform a colposcopic examination of the lower genital tract and, if indicated, colposcopically directed biopsy. For patients with an equivocal Pap test report indicating ASC-US, three options are available for follow-up management: 1) immediate colposcopy, 2) repeat Pap tests at 6-month intervals for 3 intervals, or 3) an HPV DNA test. Women with ASC-US may be considered for immediate colposcopy if concerns for patient adherence with recommended follow-up or for other clinical indications are a factor. The presence of high grade histological changes after ASC-US Pap test reports usually is <10%.
If repeat Pap tests are used to follow ASC-US results, a test should be performed every 6 months until 3 negative results are noted before the women returns to cervical cancer screening at a normal interval for age. If subsequent Pap tests demonstrate progression to SIL, follow-up should be conducted according to ASCCP Consensus Guidelines (i.e., frequent colposcopy and directed cervical biopsy). If specific infections other than HPV are identified, the patient might need to have a repeat Pap test after appropriate treatment for those infections. In the majority of instances, even in the presence of some severe infections, Pap tests will be reported as satisfactory for evaluation, so they may be read and final reports produced without the necessity to treat and repeat the Pap test. When repeating the Pap test is necessary because of an unsatisfactory for interpretation report, the repeat test must be interpreted by the laboratory as satisfactory and also be negative before returning the woman to Pap tests at regularly scheduled intervals.
A third strategy for managing patients with ASC-US Pap test results involves testing for HPV DNA. Whereas conducting HPV testing in some STD clinics might not be possible or appropriate because of inadequate resources, such testing might be appropriate in other public health clinic settings. Only one FDA-cleared test exists, the Digene Hybrid Capture II. The HPV DNA test may be performed by 1) co-collecting a specimen; 2) using a supplied swab at the time of the Pap test, if conventional cytology is used; 3) reflex testing, if liquid-based cytology is used and enough residual material is available in the cytology test vial; or 4) scheduling a separate follow-up appointment when the Pap test report results are known. If the high-risk HPV DNA test is positive, women are referred immediately for colposcopy, and if indicated, directed cervical biopsy. Because many public health clinics, including the majority of STD clinics, cannot provide clinical follow-up of abnormal Pap tests, women with Pap tests demonstrating low or high grade SIL or ASC-US usually need a referral to other local health-care providers or clinics for colposcopy and biopsy. Clinics and health-care providers who offer Pap test screening services but cannot provide appropriate colposcopic follow-up of abnormal Pap tests should arrange referral to health-care facilities in which 1) a patient will be promptly evaluated and treated and 2) the results of the evaluation will be reported to the referring clinic or health-care provider. Clinics and health-care providers should develop protocols that identify women who miss follow-up appointments so that these women can be located and scheduled for needed studies and management, and they should reevaluate such protocols routinely. Pap test results, type and location of follow-up appointments, and results of follow-up appointments should be clearly documented in the clinic record. The establishment of colposcopy and biopsy services in local health departments, especially in circumstances in which referrals are difficult and follow-up is unlikely, should be considered if resources are available.
Other considerations in performing Pap tests include the following:
The Pap test should not be considered a screening test for STDs.
All women, regardless of sexual orientation (heterosexual women and those who identify themselves as lesbian or bisexual), should be considered for cervical cancer screening in an STD clinic setting.
If a woman is menstruating, a Pap test should be postponed, and the woman should be advised to have a Pap test at the earliest opportunity.
The presence of a mucopurulent discharge should not delay the Pap test. The test can be performed after careful removal of the discharge with a saline-soaked cotton swab.
Women who have external genital warts do not need Pap tests more frequently than women who do not have warts, unless otherwise indicated.
The sequence of Pap testing in relation to collection of other cervicovaginal specimens does not appear to influence Pap test results or their interpretation. Therefore, when other cultures or specimens are collected for STD diagnoses, the Pap test can be obtained last.
Women who have had a total hysterectomy do not require a routine Pap test unless the hysterectomy was performed because of cervical cancer or its precursor lesions. In these situations, women should be advised to continue follow-up with the physician(s) who provided health care at the time of the hysterectomy, if possible. If the cervix remains after a hysterectomy, a woman should receive regularly scheduled Pap tests.
Health-care providers who receive basic retraining on Pap test collection and clinics that use simple quality assurance measures obtain fewer unsatisfactory tests. The use of cytobrushes and brooms also improves the number of satisfactory Pap tests.
Whereas evidence supports the option of HPV testing for the triage of women with ASC-US Pap test reports, this option might not be appropriate in an STD clinic because of limited resources. Studies to define the cost-effectiveness of HPV testing for the triage of women with ASC-US Pap tests are ongoing. The HPV test strategy that might be most cost-effective is the collection of a cervical swab placed in liquid media (i.e., liquid-based cytology or collection of a separate swab stored in HPV DNA transport media) during the initial visit when a Pap test is collected. When the Pap test report is available, an HPV DNA test can be performed on the residual material, if indicated, without the patient needing another clinic visit.
Liquid-based cytology is an alternative to conventional Pap tests; it has a higher sensitivity for detection of SIL and can facilitate HPV testing in women with ASC-US. However, liquid-based cytology has a lower specificity, resulting in more false-positive tests and, therefore, more administrative and patient-related costs, which could reduce the cost-effectiveness of cervical cancer screening and increase the risk of patient harm because of unnecessary follow-up tests.
Pregnant women should have a Pap test as part of routine prenatal care. A cytobrush and an Ayers spatula might be used for obtaining Pap tests in pregnant women.
Several studies have documented an increased prevalence of SIL in HIV-infected women.[200,201] The following recommendations for Pap test screening among HIV-infected women are consistent with other guidelines published by the U.S. Department of Health and Human Services and are based partially on the opinions of professionals knowledgeable about the care and management of cervical cancer and HIV infection in women.
After obtaining a complete history of previous cervical disease, HIV-infected women should be provided a comprehensive gynecologic examination, including a pelvic examination and Pap test, as part of their initial evaluation. A Pap test should be obtained twice in the first year after diagnosis of HIV infection and, if the results are normal, annually thereafter. If the results of the Pap test are abnormal, care should be provided according to the ASCCP Consensus Guidelines for Management of Abnormal Cervical Cytology. Women with cytological reports of ASC-US, low or high-grade SIL or squamous cell carcinoma, regardless of CD4+ count or antiretroviral treatment status, should undergo colposcopy and directed biopsy. Colposcopy and biopsy are not indicated in HIV-positive women with negative Pap test reports.
Some STDs can be effectively prevented through preexposure vaccination. Vaccines are under development or are undergoing clinical trials for certain STDs, including HIV and HSV. However, the only vaccines currently available are for prevention of HAV, HBV, and HPV infection. Vaccination efforts focus largely on integrating the use of these available vaccines into STD prevention and treatment activities.
Every person being evaluated or treated for an STD, who is not already vaccinated, should receive hepatitis B vaccination. In addition, some persons (e.g., MSM and illegal-drug users) should receive hepatitis A vaccination.
Hepatitis A, caused by infection with HAV, has an incubation period of approximately 28 days (range: 15--50 days). HAV replicates in the liver and is shed in high concentrations in feces from 2 weeks before to 1 week after the onset of clinical illness. HAV infection produces a self-limited disease that does not result in chronic infection or chronic liver disease. However, 10%--15% of patients might experience a relapse of symptoms during the 6 months after acute illness. Acute liver failure from hepatitis A is rare (overall case-fatality rate: 0.5%). The risk for symptomatic infection is directly related to age, with >80% of adults having symptoms compatible with acute viral hepatitis and the majority of children having either asymptomatic or unrecognized infection. Antibody produced in response to HAV infection persists for life and confers protection against reinfection.
HAV infection is primarily transmitted by the fecal-oral route, by either person-to-person contact, or through consumption of contaminated food or water. Although viremia occurs early in infection and can persist for several weeks after onset of symptoms, bloodborne transmission of HAV is uncommon. HAV occasionally might be detected in saliva in experimentally infected animals, but transmission by saliva has not been demonstrated.
In the United States, nearly half of all reported hepatitis A cases have no specific risk factor identified. Among adults with identified risk factors, the majority of cases are among MSM, persons who use illegal drugs, and international travelers. Because transmission of HAV during sexual activity probably occurs because of fecal-oral contact, measures typically used to prevent the transmission of other STDs (e.g., use of condoms) do not prevent HAV transmission. In addition, efforts to promote good personal hygiene have not been successful in interrupting outbreaks of hepatitis A. Vaccination is the most effective means of preventing HAV transmission among persons at risk for infection, many of whom might seek services in STD clinics.
The diagnosis of hepatitis A cannot be made on clinical grounds alone and requires serologic testing. The presence of IgM antibody to HAV is diagnostic of acute HAV infection. A positive test for total anti-HAV indicates immunity to HAV infection but does not differentiate current from previous HAV infection. Although usually not sensitive enough to detect the low level of protective antibody after vaccination, anti-HAV tests might be positive after hepatitis A vaccination.
Patients with acute hepatitis A usually require only supportive care, with no restrictions in diet or activity. Hospitalization might be necessary for patients who become dehydrated because of nausea and vomiting and is critical for patients with signs or symptoms of acute liver failure. Medications that might cause liver damage or are metabolized by the liver should be used with caution among persons with hepatitis A.
Two products are available for the prevention of HAV infection: hepatitis A vaccine ( Table 2 ) and immune globulin (Ig) for IM administration. Hepatitis A vaccines are prepared from formalin-inactivated, cell-culture--derived HAV and have been available in the United States since 1995, initially for persons aged ≥2 years. In 2005, the vaccines were approved by FDA for persons aged ≥12 months. Administered IM in a 2-dose series, these vaccines induce protective antibody levels in virtually all adults. By 1 month after the first dose, 94%--100% of adults have protective antibody levels; 100% of adults develop protective antibody after a second dose. In randomized controlled trials, the equivalent of 1 dose of hepatitis A vaccine administered before exposure has been 94%--100% effective in preventing clinical hepatitis A. Kinetic models of antibody decline indicate that protective levels of antibody persist for at least 20 years.
A combined hepatitis A and hepatitis B vaccine have been developed and licensed for use as a 3-dose series in adults aged ≥18 years (see Table 3 , Hepatitis B). When administered IM on a 0-, 1-, and 6-month schedule, the vaccine has equivalent immunogenicity to that of the monovalent vaccines.
Hepatitis A vaccine is available for eligible children and adolescents aged <19 years through the Vaccines for Children program (telephone: 800-232-2522).
Ig is a sterile solution of concentrated immunoglobulins prepared from pooled human plasma processed by cold ethanol fractionation. In the United States, Ig is produced only from plasma that has tested negative for hepatitis B surface antigen, antibodies to HIV and HCV, and HCV RNA. In addition, the process used to manufacture Ig inactivates viruses (e.g., HBV, HCV, and HIV). When administered IM before or within 2 weeks after exposure to HAV, Ig is >85% effective in preventing HAV infections.
Persons in the following groups who are likely to be treated in STD clinic settings should be offered hepatitis A vaccine: 1) all MSM; 2) illegal drug users (both injecting and noninjecting drugs); and 3) persons with CLD, including persons with chronic HBV and HCV infection who have evidence of CLD.
Prevaccination Serologic Testing for Susceptibility
Approximately one third of the U.S. population has serologic evidence of previous HAV infection, which increases directly with age and reaches 75% among persons aged >70 years. Screening for HAV infection might be cost-effective in populations where the prevalence of infection is likely to be high (e.g., persons aged >40 years and persons born in areas of high HAV endemicity). The potential cost-savings of testing should be weighed against the cost and the likelihood that testing will interfere with initiating vaccination. Vaccination of a person who is already immune is not harmful.
Postvaccination Serologic Testing
Postvaccination serologic testing is not indicated because the majority of persons respond to the vaccine. In addition, the commercially available serologic test is not sensitive enough to detect the low, but protective, levels of antibody produced by vaccination.
Previously unvaccinated persons exposed to HAV (e.g., through household or sexual contact or by sharing illegal drugs with a person who has hepatitis A) should be administered a single IM dose of Ig (0.02 mL/kg) as soon as possible but not >2 weeks after exposure. Persons who have had 1 dose of hepatitis A vaccine at least 1 month before exposure to HAV do not need Ig. If hepatitis A vaccine is recommended for a person receiving Ig, it can be administered simultaneously at a separate anatomic injection site. The use of hepatitis A vaccine alone is not recommended for PEP.
Limited data indicate that vaccination of persons with CLD and of HIV-infected persons results in lower seroprotection rates and antibody concentrations. In HIV-infected persons, antibody response might be directly related to CD4+ levels.
Morbidity and Mortality Weekly Report. 2006;55(30):1-94. © 2006 Centers for Disease Control and Prevention (CDC)
Cite this: Sexually Transmitted Diseases Treatment Guidelines, 2006 - Medscape - Aug 04, 2006.