Essentials of Diagnosis
- Privacy, confidentiality, and legal disease reporting concerns affect detection and treatment.
- Suspicion or diagnosis of one sexually transmitted disease (STD) should prompt screening tests for others.
- Diagnosis of an STD should always include identification and treatment of partners, and education to reduce risk of future infection.
STDs include sexually transmitted infections and the clinical syndromes they cause. Based on estimates there are up to 19 million new STDs in the United States annually, almost half of them among persons aged 15-24 years. Rates in the United States are among the highest in the developed world.
Although all sexually active individuals are susceptible to infection, adolescents and young adults are most commonly affected. Reasons for this include (1) adolescents’ biological susceptibility to increased morbidity (eg, cervical dysplasia in women exposed to human papillomavirus [HPV] as adolescent girls), (2) an attitude of invincibility, (3) lack of knowledge about the risks and consequences of STDs, and (4) barriers to health care access. Chlamydia and gonorrhea can result in infertility if left untreated. In many instances, these infections may be asymptomatic and not diagnosed. International travelers may be another population at increased risk for STDs and may benefit from pretravel counseling.
This chapter emphasizes the clinical presentation, diagnostic evaluation, and treatment of STDs commonly found in the United States. Readers of this chapter should be able to:
- Differentiate common STDs on the basis of clinical information and laboratory testing.
- Treat STDs according to current guidelines.
- Intervene in patients’ lives to reduce risk of future STD acquisition.
The discussion draws greatly from the most recent Centers for Disease Control and Prevention (CDC) guidelines for treatment of STDs. We are indebted to the individuals who worked to develop these recommendations.
Federal and state laws create disease-reporting requirements for many STDs. Gonorrhea, Chlamydia, chanchroid, syphilis, and AIDS are reportable in every state. HIV is reportable in many states. Because reporting requirements for other diseases vary by state, clinicians should contact their local health department for pertinent information.
Privacy and confidentiality concerns are different for STDs than for general medical information. Patients generally experience greater anxiety about information pertaining to a possible diagnosis of an STD, and this may limit their willingness to disclose clinically pertinent information. Conversely, legal requirements for disease reporting and health department partner notification programs can inadvertently compromise patient confidentiality if not handled with the utmost professionalism. Furthermore, although minors generally require parental consent for nonemergent medical care in all states, minors can be diagnosed and treated for STDs without parental consent. Additionally, many US states legislation may permit physicians to prescribe treatment for the heterosexual partners of men or women with Chlamydia or gonorrhea without examining the partner. Thus, laws in different jurisdictions create additional options and complexities in treating STDs. Practitioners need to be familiar with local requirements.
Intervening in patients’ lives to reduce their risk of disease due to STDs is no less important than reducing risk due to smoking, inadequate exercise, poor nutrition, and other health risks. STD risk assessment should prompt providers to undertake discussion of risk reduction, and thus disease prevention. Physicians’ effectiveness depends on their ability to obtain an accurate sexual history employing effective counseling skills. Specific techniques include creating a trusting, confidential environment; obtaining permission to ask questions about STDs; demonstrating a nonjudgmental, optimistic attitude; and combining information collection with patient education, using clear, mutually understandable language (see Chapter 17). Prevention is facilitated by an environment of open, honest communication about sexuality.
US Preventive Services Task Force (USPSTF) recommends high-intensity behavioral counseling to prevent sexually transmitted infections (STIs) for all sexually active adolescents and for adults at increased risk for STIs, for example, adults with current STIs or infections within the past year, who have multiple current sexual partners, or who are members of a population with a high rate of STIs. Recommendations for changes in behavior should be tailored to the patient’s specific risks and needs; simple suggestions such as keeping condoms available have been shown to be effective. Brief counseling using personalized risk reduction plans and culturally appropriate videos can significantly increase condom use and prevent new STDs, and can be conducted even in busy public clinics with minimal disruption to clinic operations. Effective interventions to reduce STDs in adolescents can extend beyond the examination room and include school-based and community-based education programs. Characteristics of successful interventions include: multiple sessions, most often in groups, with total duration from 3 to 9 hours, or two 20-minute counseling sessions before and after HIV testing. Individuals with chronic infections (eg, herpes simplex virus [HSV] and HPV) will need counseling tailored to help them accurately understand their infection and effectively manage symptoms and transmission risk.
For sexually active patients, male condoms are effective in reducing the sexual transmission of HIV infection. When used correctly and consistently, male latex condoms can reduce the risk of other STIs including Chlamydia, gonorrhea, and Trichomonas. Condoms may afford some protection against transmission of HSV, and may mitigate some adverse consequences of infection with HPV, as their use has been associated with higher rates of regression of cervical intraepithelial neoplasia and clearance of HPV in women.
Effectiveness depends on correct, consistent use. Patients should be instructed to use only water-based lubricants. Providers may need to demonstrate how to place a condom on the penis via a suitable model, especially for persons who may be inexperienced with condom use.
Nonoxonyl-9 spermicide is not recommended for STI/HIV prevention Some may confuse contraception with disease prevention; nonbarrier methods of contraception such as hormonal contraceptives or surgical sterilization do not protect against STDs. Women employing these methods should be counseled about the role of condoms in prevention of STDs.
Vaccination for hepatitis B virus (HBV) is indicated for all unvaccinated adolescents, all unvaccinated adults at risk for HBV infection, and all adults seeking protection from HBV infection. Other settings where all unvaccinated persons should receive vaccination include correctional facilities, drug abuse treatment and prevention services centers, health care settings serving men who have sex with men, and HIV testing and treatment facilities. Additionally, individuals with chronic liver disease (including chronic HBV or hepatitis C infection), end-stage renal disease, and potential occupational or travel exposure should be vaccinated. The prevalence of past exposure to HBV in homosexual men and injection drug users may render prevaccination testing cost effective, although it may lower compliance. For this reason, if prevaccination testing is employed, patients should receive their first vaccination dose when tested. If employed, HBV core antibody testing is an effective screen for immunity.
Vaccination for hepatitis A virus (HAV) is indicated for homosexual or bisexual men, persons with chronic liver disease (including hepatitis B and C), and persons who use illegal drugs; additionally, some individuals with occupational or travel exposure should be vaccinated. In cases of sexual or household contact with someone with HAV, hepatitis A vaccine or immune globulin should be administered as soon as possible after exposure. Information about the relative efficacy of vaccine compared with immune globulin postexposure is limited, and no data are available for persons aged elder than 40 years or those with underlying medical conditions. (For additional information on hepatitis A and B, see Chapter 31.)
Two HPV vaccines are available and licensed for females aged 9-26 years to prevent cervical precancers and cancers, the quadrivalent HPV (Gardasil) and the bivalent HPV vaccine (Cervarix). Universal vaccination of females aged 11-12 years is recommended with either vaccine, as is catch-up vaccination for females aged 13-26 years. The quadrivalent HPV vaccine (Gardasil) may be given to males aged 9 through 26 years to prevent genital warts. Experimental vaccines are also being explored for other STDs.
Following treatment of an individual patient, treatment of asymptomatic partners of a diagnosed patient is commonly employed in STD treatment. For patients with multiple partners, it may be difficult to identify the source of infection. Partner treatment should be recommended for sexual contacts occurring prior to diagnosis within the time intervals indicated for each disease:
- Chancroid, 10 days
- Granuloma inguinale, 60 days
- Lymphogranuloma venereum, 30 days
- Syphilis, up to 90 days, even if the partner tests seronegative
- Chlamydial infection, 60 days
- Gonorrhea, 60 days
- Epididymitis, 60 days
- Pelvic inflammatory disease (PID), 60 days
- Pediculosis pubis, 30 days
- Scabies, 30 days
Although in general physicians must examine a patient directly before prescribing treatment, when prior medical evaluation and counseling is not feasible, or resource limitations constrain evaluation and diagnosis, other partner management options may be considered. One of these is partner-delivered therapy, in which the patient diagnosed with Chlamydia or gonorrhea delivers the prescribed treatment to his or her partner; this option is affected by state laws and regulations.
Repeat testing at 3 months following treatment is indicated for persons with Chlamydia or gonorrhea, due to the increased incidence of reinfection. Patients should also be instructed to avoid sexual contact for the duration of therapy to prevent further transmission. Patients taking single-dose azithromycin for Chlamydia infection should be instructed to avoid sexual contact for 7 days. Patients must also be instructed to avoid contact with their previous partner(s) until both patient and partner complete treatment.
Some form of STD screening, such as questions asked during the history interview or included in routine history forms, should be a universal practice for all patients, with periodic and regular updating. Content, frequency, and additional screening should be determined by individual patient circumstances, local disease prevalence, and research documenting effectiveness and cost-benefit. Table 14-1 summarizes current recommendations for STD screening from the USPSTF.
| Infection | Recommendation |
|---|---|
| Chlamydia | Screen all sexually active women aged 25 y and younger, and other asymptomatic women at increased risk for infection (eg, unmarried, having a prior history of STD, having new or multiple sex partners, having cervical ectopy) |
| Gonorrhea | Screen all sexually active women, including those who are pregnant, for gonorrhea infection if they are at increased risk for infection (eg, age <25 y, previous gonorrhea, or other STD, new or multiple sex partners, inconsistent condom use, sex work, and drug use) |
| Hepatitis B | Screen all pregnant women at their first prenatal visit |
| HIV | Screen all pregnant women Screen all adolescents and adults at increased risk for HIV infection (eg, men who have had sex with men after 1975; men and women having unprotected sex with multiple partners; past or present injection drug users; men and women who exchange sex for money or drugs or have sex partners who do; individuals whose past or present sex partners were HIV-infected, bisexual, or injection drug users; persons being treated for STDs; persons with a history of blood transfusion between 1978 and 1985; persons seen in high-risk or high-prevalence clinical settings; and persons who request an HIV test) |
| Syphilis | Screen all pregnant women Screen persons at increased risk for syphilis infection (eg, men who have sex with men and engage in high-risk sexual behavior, commercial sex workers, persons who exchange sex for drugs, and those in adult correctional facilities) |
1. Chlamydia and Gonorrhea—Annual screening of all sexually active women younger than 25 years is recommended, as is screening of older women with risk factors (eg, those who have a new sex partner or multiple sex partners).
The benefits of Chlamydia trachomatis screening in women have been demonstrated in areas where screening programs have reduced both the prevalence of infection and rates of PID. Evidence is insufficient to recommend routine screening for C trachomatis in sexually active young men, based on feasibility, efficacy, and cost-effectiveness. However, screening of sexually active young men should be considered in clinical settings with a high prevalence of Chlamydia (eg, adolescent clinics, correctional facilities, and STD clinics).
2. Pregnancy—Recommendations for screening pregnant women vary somewhat depending on the source. According to the CDC, pregnant women should receive a serologic test for syphilis at the onset of prenatal care, again early in the third trimester, and at delivery for high-risk women. Hepatitis B surface antigen (HBsAg) testing should be performed at the onset of prenatal care and repeated late in pregnancy for unvaccinated HBsAg-negative women at high risk (ie, those who have had more than one sex partner in the previous 6 months; have been evaluated for an STD; are current injection drug users; or have an HBsAg-positive partner). Furthermore, women at risk for HBV infection should be vaccinated for hepatitis B.
Providers of obstetric care should test for Neisseria gonorrhoeae at the onset of care if local prevalence of gonorrhea is high or if the woman is at increased risk, and testing should be repeated in the third trimester if the woman is at continued risk. Providers should test for Chlamydia at the first prenatal visit. Women younger than 25 years and those at increased risk for chlamydial infection (ie, those who have multiple partners or who have a partner with multiple partners) should also be tested again in the third trimester. Evidence does not support routine testing for bacterial vaginosis. For asymptomatic pregnant women at high risk for preterm delivery, the current evidence is insufficient to assess the balance of benefits and harms of screening for bacterial vaginosis. Symptomatic women should be evaluated and treated.
3. HIV—HIV screening is recommended for patients aged 13-64 years in all health care settings after the patient is notified that testing will be performed unless the patient declines. Repeat annual testing for HIV is indicated for any high-risk patient, including patients with a diagnosed STD or with a history of behaviors that could expose them to HIV. Testing is also indicated for patients who present with a history and findings consistent with the acute retroviral syndrome (ARS), symptoms and frequency of which appear in Table 14-2. Appropriate testing regimens include an HIV-1 screening antibody test such as enzyme immunoassay, with a confirmatory test such as the Western immunoblot. HIV-2 prevalence in the United States is very low, so routine testing is not indicated although several commercial antibody tests screen for both HIV-1 and HIV-2; HIV-2 should be considered for persons coming from areas of high HIV-2 prevalence (eg, parts of West Africa, particularly Cape Verde, Ivory Coast, Gambia, Guinea-Bissau, Mali, Mauritania, Nigeria, and Sierra Leone).
| Symptoms and Signs | Frequency (%) |
|---|---|
| Fever | 96 |
| Lymphadenopathy | 74 |
| Pharyngitis | 70 |
Rash, including: Erythematous maculopapular with lesions on face and trunk and sometimes extremities, including palms and soles Mucocutaneous ulceration involving mouth, esophagus, or genitals | 70 |
| Myalgia or arthralgia | 54 |
| Diarrhea | 32 |
| Headache | 32 |
| Nausea and vomiting | 27 |
| Hepatosplenomegaly | 14 |
| Weight loss | 13 |
| Thrush | 12 |
Neurologic symptoms, including: Meningoen cephalitis or aseptic meningitis Peripheral neuropathy or radiculopathy Facial palsy Guillain-Barré syndrome Brachial neuritis Cognitive impairment or psychosis | 12 |
Early diagnosis of ARS may present a very narrow window of opportunity to alter the course of HIV infection in the recently infected patient, and to block the source of most presumed new HIV transmission. Symptoms are common and nonspecific, making diagnosis difficult without a high index of suspicion; they include fever, malaise, lymphadenopathy, pharyngitis, and skin rash. Appropriate testing should include a nucleic acid test for HIV such as HIV-RNA polymerase chain reaction (PCR); routine HIV antibody tests are not sufficient, because they generally will not have become positive during ARS. Individuals with positive HIV tests should be referred immediately to an expert in HIV care.
HIV-infected individuals pose particular challenges for STD risk reduction. Reducing high-risk behaviors of known HIV-infected patients is a top priority, both to decrease the further spread of HIV and to limit the exposure of HIV patients to additional STDs. Persons with HIV also have substantial medical, psychological, and legal needs that are beyond the scope of this chapter.
4. Other STDs—Accepted national guidelines directing screening for other STDs do not exist. If undertaken, additional screening should be guided by local disease prevalence and an individual patient’s risk behaviors.
Sexually Transmitted Infections & Syndromes
- Presenting clinical syndromes often guide diagnosis and treatment.
- History and findings can justify presumptive treatment while awaiting laboratory confirmation of a diagnosis.
Patients who are infected with STDs rarely present with accurate knowledge of their microbiological diagnosis. More commonly, patients present with clinical syndromes consistent with one or more diagnoses, so that providers frequently employ syndromic evaluation and treatment. This approach is useful for several reasons, including the fact that more than one disease may be present, and has been employed commonly in resource-poor settings with limited access to advanced diagnostic technology.
The following recommendations for testing strategies and use of empiric treatment pending laboratory results should be adapted to take into consideration local availability of specific tests, the probability of the diagnosis based on the history and examination, disease-associated morbidity, the risk of further transmission while awaiting diagnosis, and the likelihood that an untreated patient will return for laboratory test results and treatment. Treatment information is summarized in Table 14-3 and additional treatment information appears within the text description of specific diseases where applicable.
| Disease | Recommended Regimens | Dose/Route | Alternative Regimens |
|---|---|---|---|
| Chlamydia | |||
| Uncomplicated infections in adults/adolescentsa | Azithromycin or | 1 g po | Erythromycin base 500 mg po qid x 7 d or Erythromycin ethylsuccinate 800 mg po qid x 7 d or Ofloxacinc 300 mg po bid x 7 d or Levofloxacin 500 mg po qd x 7 |
| Doxycyclineb | 100 mg po bid × 7 d | ||
| Pregnant womend | Amoxicillin or | 500 mg po tid × 7 d | Erythromycin base 250 mg po qid × 14 d or Erythromycin ethylsuccinate 800 mg p qid × 7 d or Erythromycin ethylsuccinate 400 mg po qid × 14 d Erythromycin base 500 mg po qid × 7 d |
| Azithromycin | 1 g po | ||
| Gonorrheae | |||
| Uncomplicated infections in adults/adolescents | Ceftriaxone or | 250 mg IM | Ceftizoxime 500 mg IM or Cefotaxime 500 mg IM or Cefoxitin 2 g IM plus probenecid 1 g po or Spectinomycinh 2 g IM pluse a Chlamydia recommended regimen |
| Cefiximef plus a Chlamydia recommended regimen listed above | 400 mg po | ||
| Pregnant women | Ceftriaxone or | 250 mg IM | Spectinomycinh 2 g IM pluse a Chlamydia recommended regimen |
| Cefiximef pluse a Chlamydia recommended regimen listed above | 400 mg po | ||
| Pelvic inflammatory diseaseg | Parenterali | Parenteral Ampicillin/sulbactam 3 g IV q 6 h plus doxycyclineb 100 mg po 12 h If parenteral cephalosporin therapy is not feasible, use of fluoroquinolones (levofloxacin 500 mg orally once daily or ofloxacin 400 mg bid for 14 d) with or without metronidazole (500 mg orally bid for 14 d) may be considered if the community prevalence and individual risk of gonorrhea is low. Tests for gonorrhea must be performed prior to instituting therapy and the patient managed as follows: If NAAT test is positive, parenteral cephalosporin is recommended. If culture for gonorrhea is positive, treatment should be based on results of antimicrobial susceptibility. If isolate is quinolone-resistant or antimicrobial susceptibility cannot be assessed, parenteral cephalosporin is recommended. | |
| Cefotetan or | 2 g IV q 12 h | ||
| Cefoxitin plus | 2 g IV q 6 h | ||
| Doxycyclineb or | 100 mg po or q 12 h | ||
| Clindamycin plus | 900 mg IV q 8 h | ||
| Gentamicin | 2 mg/kg IV or IM followed by 1.5 mg/kg IV or IM q 8 h | ||
| Oral treatment | |||
| Ceftriaxone or | 250 mg IM | ||
| Cefoxitin with | 2 g IM | ||
| Probenecid plus | 1 g po | ||
| Doxycyclineb ± | 100 mg po bid × 14 d | ||
| Metronidazole | 500 mg bid × 14 d | ||
| Cervicitisj | Azithromycin or | 1 g po | |
| Doxycyclineb | 100 mg po bid × 7 d | ||
| Nongonococcal urethritisj | Azithromycin or | 1 g po | Erythromycin base 500 mg po qid × 7 d or Erythromycin ethylsuccinate 800 mg po qid × 7 d or Ofloxacinc 300 mg po bid × 7 d or Levofloxacinc 500 mg po qd × 7 d |
| Doxycyclineb | 100 mg po bid × 7 d | ||
| Epididymitis | Ceftriaxone plus | 250 mg IM | For men at risk for both enteric organisms and sexually transmitted pathogens (MSM who report insertive anal intercourse) Ceftriaxone 250 mg IM + doxycycline 100 mg po bid × 10 d |
| Doxycycline | 100 mg po bid × 10 d | ||
| For acute epididymitis most likely caused by enteric organisms or with negative gonococcal culture or nucleic acid amplification test | |||
| Ofloxacinc or | 300 mg orally bid for 10 d | ||
| Levofloxacin | 500 mg orally once daily for 10 d | ||
| Trichomoniasis | Metronidazole or | 2 g po | Metronidazole 500 mg po bid × 7 d or for failure Tinidazole or metronidazole 2 g po × 5 d |
| Tinidazole | 2 g po | ||
| Vulvovaginal candidiasis | Butoconazole creamk | 2%, 5 g intravaginally × 3 d | Fluconazole 150 mg po once |
| Butoconazole 2% cream (SR)k | Single application | ||
| Clotrimazole creamk | 1%, 5 g intravaginally × 7-14 d | ||
| Clotrimazolea creamk | 2% cream 5 g intravaginally × 3 d | ||
| Miconazole creamk | 2% 5 g intravaginally × 7 d 4% tg intravaginally × 3 d | ||
| Miconazole vaginal suppositoryk | 100 mg intravaginally × 7 d 200 mg intravaginally × 3 d 1200 mg intravaginally × 1 | ||
| Nystatin | 100,000 units intravaginal tablet × 14 d | ||
| Tioconazole creamk | 6.5% 5 g intravaginally once | ||
| Terconazole creamk | 0.4% 5 g intravaginally × 7 d 0.8% 5 g intravaginally × 3 d | ||
| Terconazole vaginal suppositoryk | 80 mg intravaginally × 3 d | ||
| Bacterial vaginosis | |||
| Adults/adolescents | Metronidazole or | 500 mg po bid × 7 d | Clindamycin 300 mg po bid × 7 d or Clindamycin ovules 100 g intravaginally qhs × 3 d Tinidazole 2 gm po qd × 3 d Or Tinidazole 1 gm po day × 5 d |
| Clindamycin creamk or | 2%, one applicator full (5 g) intravaginally at bedtime × 7 d | ||
| Metronidazole gel | 0.75%, one applicator full (5 g) intravaginally, bid × 5 d | ||
| Pregnant women | Metronidazole | 250 mg po tid × 7 d or | |
| 500 mg bid × 7 d | |||
| Clindamycin | 300 mg po bid × 7 d | ||
| Chancroid |
