Sexually Transmitted Infections

Sexual contact can involve transmission of pathogens through the skin or mouth and via oral-genital, oral-anal, or hand-anal transmission of pathogens through breaks in the skin or mucosal surfaces or from inoculation by infectious body fluids. Anal penetration is particularly risky because of the likelihood of tissue trauma that results in the partner’s exposure to enteric microorganisms. The risk for contracting an STI increases with substance abuse, imprisonment, sexual activity with a partner who has been imprisoned, sexual activity with individuals being paid for sex acts, and rape or sexual assault.

Patients who engage in sexual activity with multiple partners are at high risk for transmission of STIs, particularly HIV. The Centers for Disease Control and Prevention (CDC) reports the risk for getting STIs is markedly increased among individuals who have more than one sexual partner per year versus those who have fewer partners. It should be noted that 5.2% of men between the ages of 15 and 44 report having 5 or more partners in a 12-month period, and 2% of women report the same. Additionally, 21.8% of men between the ages of 15 and 44 report having had 15 or more sexual partners, and 10.6% of women report the same.

Other high-risk practices are anal or vaginal intercourse without a condom, hand-anal contact, contact with menstrual blood during sexual activity, use of an enema before anal intercourse, and urination on broken skin or inside the body. Refer to Fig. 54.1 for guidelines provided by the CDC on the prevention of STIs.

STIs are often manifested as multiple infections. Individuals undergoing treatment for one STI should be assessed for others, including HIV. This is especially true if genital or perianal ulcerations are present.

Vertical transmission is the passage of infecting organisms from mother to neonate. Microbes can travel up the reproductive tract from the vagina or cervix and enter the intrauterine environment. Organisms that are of little consequence to healthy adults can be devastating to a fetus. Transmission can also occur through contact with the mother’s blood at birth or through breast milk, as in the case of HIV and HBV. Many STIs, such as syphilis, are transmitted through the placenta and membranes. Others, such as the herpes simplex virus type 2 (HSV-2), require actual contact by the infant with microorganisms in the birth canal. Because of the risk for blindness caused by Chlamydia trachomatis and N. gonorrhoeae, erythromycin ointment is routinely administered in the eyes of neonates as prophylaxis. This is usually done within the first hour after birth.

CDC guidelines for the primary treatment of some STI pathogens are listed in Table 54.1; the most common pathogens are discussed in the following section. All sexual contacts of an infected individual should be informed of the exposure so they can be treated. Partners should refrain from sexual activity until each is clear of infection on follow-up evaluation or, at the very least, condoms should be used until each is clear of infection.

BV is treated with metronidazole 500 mg by mouth (PO) twice a day for 7 days. Because metronidazole can cause stomach upset, it should be taken with food or a full glass of water or milk. Alcohol causes severe nausea and vomiting when ingested with metronidazole, so patients should be instructed not to drink alcoholic beverages or use products that contain alcohol, such as mouthwash, for the duration of drug therapy and for 48 hours after treatment.

Vaginal preparations are also effective in treating BV, such as metronidazole gel 0.75%, one 5-g applicator intravaginally at bedtime for 5 nights; clindamycin cream 2%, one 5-g applicator intravaginally at bedtime for 5 days; or clindamycin ovules, 100 mg intravaginally at bedtime for 3 days.

Oral drugs that are alternatives to metronidazole include tinidazole, either 2 g orally once a day for 2 days or 1 g orally once a day for 5 days, or clindamycin 300 mg orally twice a day for 7 days. Tinidazole has the same precautions with alcohol as metronidazole and should be taken with food. Tinidazole causes slightly less gastrointestinal (GI) upset than metronidazole. Patients taking clindamycin should be instructed to notify their health care provider if diarrhea develops because it may be an indication of Clostridium difficile–associated diarrhea (CDAD). Treating BV is especially important for pregnant women because of the risk of spontaneous abortion, delivery of premature or low-birthweight babies, or pelvic infection developing after delivery. Metronidazole (oral or intravaginal) or clindamycin (oral) are the drugs of choice in pregnancy, and tinidazole should not be used during the first trimester of pregnancy. None of the drugs should be used by nursing mothers because these drugs are excreted in breast milk.

The CDC recommends azithromycin 1 g orally in a single dose as treatment for C. trachomatis infections or doxycycline 100 mg orally twice a day for 7 days. Alternatively, erythromycin base 500 mg orally four times a day for 7 days, erythromycin ethylsuccinate 800 mg orally four times a day for 7 days, levofloxacin 500 mg orally once daily for 7 days, or ofloxacin 300 mg orally twice a day for 7 days may be given.

Doxycycline is contraindicated in the second and third trimesters of pregnancy. In the case of a chlamydial infection during pregnancy, azithromycin 1 g orally in a single dose is the treatment of choice. Alternatively, amoxicillin 500 mg orally three times a day for 7 days may be given. If neither azithromycin nor amoxicillin is an option, erythromycin may be used.

Neonates may contract C. trachomatis from exposure to the mother’s infected cervix during delivery. It most frequently presents as conjunctivitis that develops 5 to 12 days after delivery; however, C. trachomatis can also cause pneumonia in infants between 1 and 3 months old. Prenatal screening and treatment is the best means of prevention. Erythromycin ophthalmic ointment, administered to prevent gonococcal ophthalmia, may also prevent conjunctivitis caused by C. trachomatis.

Persons treated for Chlamydia infection should be instructed to abstain from sexual intercourse for 7 days after single-dose therapy or until a 7-day regimen is completed. Partners should be treated if they had sexual contact during the 60 days preceding the onset of symptoms or diagnosis.

Because of the development of resistant N. gonorrhoeae, dual drug therapy is recommended with ceftriaxone 250 mg given intramuscularly (IM) in a single dose plus azithromycin 1 g orally in a single dose for uncomplicated urogenital infections or oral infections. If ceftriaxone is not available, cefixime 400 mg orally in a single dose plus azithromycin 1 g orally in a single dose may be given. Use of two drugs improves treatment efficacy and slows the development of drug resistance.

For those who are allergic to cephalosporins, gemifloxacin 320 mg orally in a single dose plus azithromycin 2 g orally in a single dose may be used; or, alternatively, gentamicin 240 mg IM in a single dose plus azithromycin 2 g orally in a single dose may be used. Women who are diagnosed with N. gonorrhoeae while pregnant should be treated with ceftriaxone 250 mg in a single IM dose and azithromycin 1 g orally as a single dose. Children under 45 kg should receive 25 to 50 mg/kg intravenously (IV) or IM, not to exceed 125 mg IM in a single dose.

Neonates may contract N. gonorrhoeae from exposure to the mother’s infected cervix during delivery. The infection most frequently presents as an acute illness that develops 2 to 5 days after delivery. Prenatal screening and treatment is the best means of prevention, and most states require neonates to be administered erythromycin (0.5%) ophthalmic ointment in each eye in a single application at birth to prevent conjunctivitis caused by N. gonorrhoeae.

Persons receiving treatment for gonorrhea should be instructed to abstain from sexual activity for 7 days after treatment. Persons diagnosed with gonorrhea should also be tested for Chlamydia, syphilis, and HIV. Partners should be treated if they had sexual contact during the 60 days preceding the onset of symptoms or diagnosis.

Primary syphilis infections present with a sore, or chancre, at the site where the infection entered the body—typically, the penis in men and outer genitals or inner vagina in women. It is usually painless. The chancre develops about 3 weeks after exposure and resolves in 3 to 6 weeks without treatment. During this stage, the person is very contagious, even after the chancre has resolved.

Secondary syphilis is characterized by a skin rash that appears 2 to 8 weeks after the chancre. It may occur anywhere on the body, commonly on the hands and soles of the feet; the rash usually does not itch. Mucocutaneous lesions, fever, fatigue, sore throat, and lymphadenopathy may occur as well. The rash usually resolves in about 2 months. During this stage, the person remains very contagious, even after the rash has resolved. After the rash has resolved, a period that lasts anywhere from 1 year to 20 years goes by without any symptoms. This is called the latent stage, and it occurs in persons who have gone untreated. A person may remain contagious during the latent period, and diagnosis can only be made through blood testing.

Tertiary syphilis may occur as early as 1 year after infection or at any time during an untreated person’s lifetime. Large sores inside the body or on the skin occur in the tertiary stage, along with cardiovascular and ocular syphilis and neurosyphilis. Examination of the cerebral spinal fluid (CSF) should be done in persons in the tertiary stage to determine neurologic involvement, even in the absence of clinical neurologic findings.

To diagnose syphilis, two types of serologic testing are necessary to avoid false positives. One test should be a nontreponemal antibody test (e.g., Rapid Plasma Reagin [RPR] or Venereal Disease Research Laboratory [VDRL]) that tests for antibodies produced when a person has syphilis, although it may be produced in other diseases as well (e.g., Lyme disease or malaria). The other test should be a treponemal antibody test (e.g., fluorescent treponemal antibody absorption [FTA-ABS] or T. pallidum particle agglutination assay [TP-PA]), a test for antibodies that specifically target T. pallidum.

Treatment for primary and secondary syphilis is benzathine penicillin G, 2.4 million units given IM in one dose. Infants and children should be treated with benzathine penicillin G 50,000 units/kg IM up to the adult dose of 2.4 million units in a single dose, and these patients should be followed by a pediatric infectious disease specialist.

Adults with early latent syphilis should be treated with benzathine penicillin G 2.4 million units IM in a single dose; those with late latent syphilis or latent syphilis of unknown duration should receive benzathine penicillin G 7.2 million units total, administered as three doses of 2.4 million units IM each at 1-week intervals. Infants and children with early latent syphilis should be treated with benzathine penicillin G 50,000 units/kg IM, up to the adult dose of 2.4 million units in a single dose; those with late latent syphilis should receive benzathine penicillin G 50,000 units/kg IM, up to the adult dose of 2.4 million units, administered as three doses at 1-week intervals (total 150,000 units/kg up to the adult total dose of 7.2 million units). Infants and children should be managed by a pediatric infectious disease specialist.

Persons with tertiary syphilis should receive CSF analysis before initiating treatment. Those with normal CSF should receive benzathine penicillin G 7.2 million units total, administered as three doses of 2.4 million units IM each at 1-week intervals. Those with neurosyphilis or ocular syphilis should receive aqueous crystalline penicillin G 18 to 24 million units per day, administered as 3 to 4 million units IV every 4 hours or as a continuous infusion for 10 to 14 days. Alternatively, persons with neurosyphilis or ocular syphilis may be treated with procaine penicillin G 2.4 million units IM once daily plus probenecid 500 mg orally four times a day, both for 10 to 14 days. This alternative treatment should only be given to persons whose adherence can be ensured.

Pregnant women can pass syphilis to their fetus, with potentially fatal consequences. Benzathine penicillin G is the only treatment for syphilis during pregnancy. Pregnant women with syphilis in any stage who report they are allergic to penicillin should undergo penicillin allergy skin testing and desensitization, and then should be treated with penicillin.

Partners should be treated if they had sexual contact during the 90 days preceding the diagnosis of primary, secondary, or early latent syphilis even if serologic testing is negative. If greater than 90 days, treatment should be initiated if serologic testing is positive or if testing is not available. All persons with syphilis at any stage should be tested for HIV.

Antiviral drugs are beneficial to most symptomatic patients and are the mainstay of management. It is imperative that nurses counsel patients with herpes regarding sexual and perinatal transmission and methods to reduce transmission.

Systemic antiviral drugs can control some of the signs and symptoms of genital herpes during initial and recurrent episodes or when used for daily suppressive therapy. However, these do not cure herpes or reduce the frequency and severity of recurrent episodes following drug discontinuation. Three antiviral drugs are used in the management of genital herpes: (1) acyclovir, (2) valacyclovir, and (3) famciclovir.

Recommendations for drug therapy of initial genital herpes infections is recommended using acyclovir 400 mg orally three times a day for 7 to 10 days, acyclovir 200 mg orally five times a day for 7 to 10 days, valacyclovir 1 g orally twice a day for 7 to 10 days, or famciclovir 250 mg orally three times a day for 7 to 10 days. Treatment can be extended if healing is incomplete after 10 days of therapy.

Suppressive therapy reduces the frequency of genital herpes recurrences by 70% to 80% in patients who have frequent recurrences. Recommended regimens are acyclovir 400 mg orally twice a day, valacyclovir 500 mg orally once a day, valacyclovir 1 g orally once a day, or famciclovir 250 mg orally twice a day. Valacyclovir 500 mg once a day might be less effective than other valacyclovir or acyclovir dosing regimens in persons who have 10 episodes or more per year.

For episodic treatment to be effective, treatment should begin within 1 day of lesion onset or during the prodrome (e.g., burning, itching, or tingling) that occurs anywhere from 30 minutes to a couple of days before some outbreaks. Patients should be provided with a prescription for the drug with instructions to initiate treatment immediately when symptoms begin. The recommended regimens for episodic therapy are acyclovir 400 mg orally three times a day for 5 days, acyclovir 800 mg orally twice a day for 5 days, acyclovir 800 mg orally three times a day for 2 days, valacyclovir 500 mg orally twice a day for 3 days, valacyclovir 1 g orally once a day for 5 days, famciclovir 125 mg orally twice daily for 5 days, famciclovir 1 g orally twice daily for 1 day, or famciclovir 500 mg once, followed by 250 mg twice daily for 2 days.

Sexual partners should be evaluated, treated if symptomatic, and counseled. Asymptomatic sex partners should be questioned about a history of genital lesions and offered serologic testing for HSV infection.

The risk of vertical transmission is high (30% to 50%) among women who become infected near the time of delivery and low (<1%) among women with a prenatal history of herpes or those who become infected early in the pregnancy. Prevention of vertical transmission depends on both preventing infection during late pregnancy and avoiding exposure to viral shedding during delivery. The recommended drug regimen for suppressive therapy of pregnant women with recurrent genital herpes is acyclovir 400 mg orally three times a day or valacyclovir 500 mg orally twice a day with treatment recommended starting at 36 weeks of gestation.

Persons with acute HIV infection are at high risk for transmitting HIV to their partner because the concentration of virus in blood and genital secretions is extremely elevated. Antiretroviral therapy (ART) during acute HIV infection is recommended because it substantially reduces transmission to others. See Chapter 29 for drugs used to treat HIV.

Partners (sexual partners and those with whom needles and syringes are shared) should be notified concerning possible exposure to HIV. Early diagnosis and treatment reduces the risk for further HIV transmission. Partner notification for HIV infection should be confidential.

All pregnant women should be tested for HIV infection during the first prenatal visit. A second test during the third trimester, preferably at less than 36 weeks’ gestation, is recommended for those known to be at high risk for HIV.

There are several HPV vaccines approved for use in the United States: a bivalent vaccine that prevents infection with HPV types 16 and 18, which cause 66% of all cervical cancers; a quadrivalent vaccine that prevents infection with HPV types 6, 11, 16, and 18, which cause 90% of all genital warts; and a 9-valent vaccine that prevents infection with HPV types 6, 11, 16, 18, 31, 33, 45, 52, and 58. See Chapter 31 for a discussion on vaccines.

Because most HPV infections do no harm, they do not require treatment and tend to resolve on their own. Because of this, antiviral therapy is not recommended. Treatment is aimed at removal of genital warts and precancerous lesions and treatment of cervical cancer and includes cryotherapy (freezing) or a loop electrosurgical excision procedure (LEEP) to cut away abnormal tissue.

Condom use can lower the risk of transmitting and developing HPV infections. Limiting the number of sex partners can also reduce the risk for HPV. However, abstaining from sexual activity is the most reliable method for preventing HPV infection.

Recommended treatment is with a permethrin 1% cream rinse applied to affected areas and washed off after 10 minutes, or pyrethrins with piperonyl butoxide are applied to the affected area and washed off after 10 minutes. Alternatively, malathion 0.5% lotion can be applied to affected areas and washed off after 8 to 12 hours, or ivermectin 250 mcg/kg can be given orally and repeated in 2 weeks.

Sexual partners within the previous month should be treated, and bedding and clothing must be decontaminated. Sexual contact should be avoided until treatment is complete. Pregnant and lactating women should be treated with either permethrin or pyrethrins with piperonyl butoxide.

Treatment consists of permethrin 5% cream applied to all areas of the body from the neck down and washed off after 8 to 14 hours or ivermectin 200 mcg/kg orally, repeated in 2 weeks. Permethrin is the treatment of choice for infants and young children. Alternatively, lindane 1%—either 1 oz of lotion or 30 g of cream—applied in a thin layer to all areas of the body from the neck down and thoroughly washed off after 8 hours may be used; however, pregnant women, infants, and children under the age of 10 years should not be treated with lindane.

Bedding and clothing should be decontaminated by either machine washing, machine drying using the hottest cycle, or dry cleaning; alternatively, bedding and clothing should be removed from body contact for at least 72 hours. Persons who have had sexual, close personal, or household contact with the patient within the month preceding scabies infestation should be examined and treated if infected.

Ivermectin likely poses a low risk to pregnant women and is likely compatible with breastfeeding; however, because of limited data regarding ivermectin use in pregnant and lactating women, permethrin is the preferred treatment

The nitroimidazoles are the only class of antimicrobials effective against T. vaginalis. Metronidazole and tinidazole are approved for oral or parenteral treatment of trichomoniasis. The recommended regimen is metronidazole 2 g orally in a single dose or tinidazole 2 g orally in a single dose. Alternatively, metronidazole 500 mg orally twice a day for 7 days may be used.

Alcohol should be avoided during treatment with nitroimidazoles to prevent the likelihood of a disulfiram-like reaction. Abstinence from alcohol use should continue for 24 hours after completion of metronidazole or 72 hours after completion of tinidazole. Concurrent treatment of all sex partners is critical to prevent transmission and reinfection.

T. vaginalis is readily passed between sex partners. The best way to prevent infection is through consistent and correct use of condoms. Partners of men who have been circumcised might have a somewhat reduced risk of T. vaginalis infection.

T. vaginalis infection in pregnant women is associated with premature rupture of membranes, preterm delivery, and delivery of a low-birthweight infant. The recommended treatment regimen in pregnant women is metronidazole 2 g orally in a single dose.

Treatment with topically applied azole drugs results in symptomatic relief and negative cultures in 80% to 90% of patients who complete therapy. A variety of over-the-counter (OTC) and prescription drugs may be used to treat VVC. Treatment regimens include OTC and prescription intravaginal agents.

Topical agents usually cause no systemic side effects, although local burning or irritation might occur. Oral azoles occasionally cause nausea, abdominal pain, and headache.

VVC occurs frequently during pregnancy. Only topical azole therapies, applied for 7 days, are recommended for use among pregnant women. Uncomplicated VVC is not usually acquired through sexual intercourse, thus treatment of sexual partners is not necessary.