7.4 Introduction to Sexually Transmitted Infections and Drugs to Treat Them

Bacterial Vaginosis

Bacterial vaginosis (BV) is a common cause of vaginal discharge and occurs when the normal bacterial flora of the vagina shift from the normally dominant lactobacilli to other pathogenic species. Disruption of the normal vaginal flora can occur for a variety of reasons, but sex with multiple partners, douching, and not using condoms are cited as the most common risk factors. Individuals with BV may be asymptomatic or can have signs and symptoms such as vaginal discharge and fishy odor. Treatment is necessary to prevent outcomes such as acquisition of other STIs, pelvic inflammatory disease (PID), and preterm delivery if pregnant.

Chlamydia

Chlamydia is one of the most reported STIs in the United States, with more than 1.6 million cases being reported in 2021 (CDC, 2023a). The condition is caused by the organism Chlamydia trachomatis, which can spread during sexual intercourse. Clients with chlamydia may present with painful urination and urethral discharge in males or vaginal discharge in females. However, many affected individuals are asymptomatic and are diagnosed only if screened. Screening usually includes a nucleic acid amplification test (NAAT) to look for the presence of the organism. Untreated cases of chlamydia can progress to PID in female clients, which may result in chronic pain and infertility.

Gonorrhea

Gonorrhea is the second most reported STI in the United States, with over 700,000 cases being reported in 2021 (CDC, 2023a). The condition is caused by Neisseria gonorrhoeae, which is transmitted during sexual contact. As with chlamydia, some clients will remain asymptomatic, which aids in the spread to sexual partners. The most common presenting symptoms include mucopurulent penile discharge and painful urination. Diagnosis is made using a NAAT to look for presence of the organism. Complications from untreated cases of gonorrhea include PID, infertility, and increased risk for HIV infection.

Syphilis

Syphilis is a bacterial infection caused by the spirochete Treponema pallidum. It can be transmitted perinatally and through sexual contact. Syphilis can present in a variety of ways depending on the stage to which it has advanced. Primary syphilis is associated with a painless chancre on tissue that was exposed to the organism (usually the genital tissue). Secondary syphilis occurs as the organism spreads through the lymph system, producing skin lesions throughout the body. The third stage of syphilis is the latent phase, when the symptoms of the secondary stage disappear. In the most advanced stage, the organism can invade the body’s organ systems, including the central nervous system (neurosyphilis) and the cardiovascular system (cardiovascular syphilis) and can result in stroke, seizures, vision problems, and death. Several tests can be performed to diagnose syphilis; the rapid plasma reagin (RPR) and venereal disease research laboratory (VDRL) tests are the most common.

Herpes Simplex

Herpes simplex virus (HSV), discussed earlier in the chapter, is a major cause of genital ulcerations in the United States, with an estimated 572,000 cases reported each year (CDC, 2021). Despite its prevalence, many individuals are asymptomatic, leading to transmission of the condition without the person’s knowledge. Ulcerations are often painful and can occur in multiple episodes per year in susceptible individuals. Individuals with HSV infection are also more susceptible to HIV infection.

Human Papillomavirus

Human papillomavirus (HPV) is a DNA virus that spreads through skin-to-skin contact. HPV infection is also prevalent; an estimated 42.5 million people contracted the virus in 2018 (CDC, 2021). Most individuals who contract HPV remain asymptomatic; however, the signs and symptoms include genital warts, which can produce varying levels of discomfort. Many subtypes of HPV exist and are linked to different types of cancer, including cervical, anal, vaginal, and oropharyngeal cancers. This association prompted development of an HPV vaccine that protects against nine strains of the virus. The vaccine protects against cervical, vulvar, and vaginal cancer in females along with anal cancer and genital warts in both females and males.

Antimicrobials

The ideal antimicrobial to treat an STI is one that is effective, has few adverse effects, is inexpensive, and can be given as a single dose or short course to ensure adherence. However, drug resistance continues to be problematic for drugs used to treat STIs. Therefore, nurses should make sure to regularly review current guidelines for the treatment of STIs. The following are common antimicrobials used to treat STIs:

• Metronidazole: Metronidazole has good activity against anaerobic bacteria and protozoa. For this reason, metronidazole is recommended for treatment of BV and trichomoniasis. The client’s sexual partners should also be treated with metronidazole to prevent reinfection. Metronidazole may be given either orally or as a vaginal gel.
• Clindamycin: Clindamycin is an alternative treatment for BV if metronidazole cannot be used. It can be given orally or as a vaginal cream. Oral options are less preferred due to the risk for C. difficile infection and severe diarrhea.
• Penicillin: Penicillin is considered the treatment of choice for syphilis. It can be given as a single-dose, long-acting intramuscular injection to assist with client adherence. Continuous intravenous infusion may be necessary to treat neurosyphilis.
• Ciprofloxacin: Ciprofloxacin is a fluoroquinolone antibiotic that has some activity against N. gonorrhea and C. trachomatis. Due to fluoroquinolone overuse, antimicrobial resistance is a major issue with continued use of this drug, and guidelines list ciprofloxacin only as an alternative agent if clients cannot receive other first-line therapies such as ceftriaxone or doxycycline. Clients should be educated to avoid taking ciprofloxacin with any multivitamins or dairy products because iron and calcium can bind to the drug and render it ineffective.
• Ceftriaxone: Ceftriaxone is the treatment of choice for gonorrhea. It can be given as a single intramuscular injection for most cases of uncomplicated gonorrhea. The main adverse effect expected with this treatment is pain at the injection site, which can be offset by mixing ceftriaxone with a local anesthetic such as lidocaine.
• Doxycycline: Doxycycline is a tetracycline antibiotic that is the treatment of choice for chlamydia. Single doses of the macrolide azithromycin used to be the preferred therapy, but due to rising chlamydial resistance, doxycycline is now considered first-line therapy. The downside of doxycycline is that it must be given twice daily over 7 days, so nurses should impress upon the client the need to take all doses to prevent treatment failure and to control resistance.

• Erythromycin: Erythromycin is a macrolide antibiotic that can be used for treating neonatal gonococcal and chlamydial infections acquired perinatally from the birthing parent. Known or suspected infections can be treated with systemically administered erythromycin, and ophthalmic ointment administered to newborns as prophylaxis is standard of care in many U.S. hospitals. Approximately 1 cm in length of ointment should be administered into each lower conjunctival sac. The ointment should not be flushed from the eye following instillation. A new tube should be used for each infant.

Antivirals

Although not curative for any viral STIs, the antivirals acyclovir, valacyclovir, and famciclovir are used to help manage the symptoms of HSV and prevent spread to sexual partners. Nurses should inform clients taking antivirals for STIs that even if they do not have active lesions, viral shedding can still occur and thereby spread the infection to partners. If clients are taking antivirals for episodic management of HSV-related lesions, they should begin therapy within 24 hours of symptom onset to ensure drug efficacy. Chronic suppressive therapy, in which clients take the medication every day regardless of symptom status, can help prevent spread to sexual partners, but nurses should instruct clients to use additional protective measures such as condoms if the partner does not have HSV.

Table 7.11 lists commonly used medications to treat STIs and typical routes and dosing for adult clients.

Nursing Implications

The nurse should do the following for clients who are taking medications for STIs:

• Monitor for signs and symptoms of anaphylaxis (e.g., shortness of breath, difficulty breathing, difficulty swallowing).
• Advise the client to take the entire prescribed course of the drug to ensure adequate treatment and to reduce the development of drug resistance.
• Instruct the client to maintain adequate hydration; monitor kidney function for renally eliminated medications such as penicillin and ciprofloxacin.
• Educate about safer sex practices and ways to avoid STIs in the future.
• Mix ceftriaxone with lidocaine, as ordered, to reduce the pain of intramuscular injections for treatment of gonorrhea.
• Provide client teaching regarding the drug and when to call the health care provider. See below for client teaching guidelines.