Chapter 87. Sexually Transmitted Diseases

This chapter covers the major sexually transmitted diseases (STDs) in the United States, with the exception of human immunodeficiency virus, which is discussed in Chapter 92. Vaginitis and pelvic inflammatory disease (PID) are covered separately in Chapters 63 and 64, respectively.

Multiple STDs infections frequently occur concurrently, compliance and follow-up are often limited or unreliable, infertility and other long-term morbidities may result from lack of treatment. When an STD is suspected, treat with single-dose regimens whenever possible. Ascertain pregnancy status and consider an obstetrics consultation if the patient is pregnant. Screen for other STDs (HIV infection, syphilis, and hepatitis) in the ED or through follow-up. Provide counseling for STD prevention in the ED and assure HIV testing in the ED or through follow-up as indicated. Advise that the partner(s) seek treatment and counsel on the appropriate time to reengage in sexual relations. Arrange follow-up as local resources allow.

Clinical Features

Chlamydia trachomatis causes urethritis, epididymitis, orchitis, proctitis, or Reiter syndrome (nongonococcal urethritis, conjunctivitis, and rash) in men and urethritis, cervicitis, PID, and infertility in women. In both sexes, asymptomatic infection is common. There is a high incidence of coinfection with Neisseria gonorrhoeae. The incubation period is 1 to 3 weeks, with symptoms varying from mild dysuria with purulent or mucoid urethral discharge to sterile pyuria and frequency (urethritis). Women may present with mild cervicitis or with abdominal pain, findings of PID, or peritonitis. Men may present with a tender swollen epididymis or testicle.

Diagnosis and Differential

Diagnosis is best made with indirect detection methods such as enzyme-linked immunosorbent assay or DNA probes, which have a sensitivity of 75% to 90%. The Centers for Disease Control and Prevention (CDC) recommends a nucleic acid amplification test to be used as screening tests for Chlamydia. Culture is possible but difficult and produces a low yield.

Emergency Department Care and Disposition

1. Azithromycin 1 gram PO as a single dose or doxycycline 100 milligrams PO twice daily for 7 days is the treatment of choice for uncomplicated urethritis or cervicitis.

2. Alternatives include 7-day treatment with erythromycin 500 milligrams PO 4 times a day, ofloxacin 300 milligrams twice daily, or levofloxacin 500 milligrams PO daily.

Clinical Features

Neisseria gonorrhoeae (GC) is a gram-negative diplococcus that causes urethritis, epididymitis, orchitis, and prostatitis in men and urethritis, cervicitis, PID, and infertility in women. Rectal infection and proctitis with mucopurulent anal discharge and pain can occur in both sexes. The incubation period ranges from 3 to 14 days. Women tend to present with nonspecific lower abdominal pain and mucopurulent vaginal discharge with findings of cervicitis and possibly PID. Eighty percent to 90% of men develop symptoms of urethritis: dysuria and purulent penile discharge within 2 weeks. Men also may present with acute epididymitis and orchitis or prostatitis. Occasionally, GC can be isolated from the throat, but it rarely causes symptomatic pharyngitis. Disseminated GC is a systemic infection that occurs in 2% of untreated patients with GC, most often women, and is the most common cause of infectious arthritis in young adults. An initial febrile bacteremic stage includes skin lesions (tender pustules on a red base, usually on the extremities, and may include palms and soles), tenosynovitis, and myalgias. Over the next week, these symptoms subside, followed by mono- or oligoarticular arthritis with purulent joint fluid.

Diagnosis and Differential

For uncomplicated GC, urethral or cervical cultures are the standard diagnostic tests. A Gram stain of urethral discharge showing intracellular gram-negative diplococci is very useful in men; cervical smears are unreliable in women. Diagnosis of disseminated GC is primarily clinical because results of culture of blood, skin lesions, and joint fluid are positive in only 20% to 50% of patients. Culturing the cervix, rectum, and pharynx may improve the yield. A positive GC culture result from a partner supports the diagnosis.

Emergency Department Care and Disposition

1. Effective therapy for uncomplicated gonorrhea (not PID) includes single-dose regimens of cefixime 400 milligrams PO, or ceftriaxone 250 milligrams IM.

2. Alternatives include single-dose regimens of spectinomycin 2 grams IM, or ceftizoxime, 500 milligrams IM single dose, or cefoxitin, 2 grams IM single dose, plus probenecid, 1 gram PO single dose, or cefotaxime, 500 milligrams IM single dose.

3. Disseminated gonorrhea is treated initially with parenteral ceftriaxone 1 gram daily IM/IV, 24 to 48 hours after there is clinical improvement, then the patient can be switched to oral cefixime 400 milligrams daily for 7 to 10 total antibiotic therapy days.

4. Treatment for possible coinfection with Chlamydia also should be given (see above).

Clinical Features

Trichomonas vaginalis is a flagellated protozoan that causes vaginitis with malodorous yellow-green discharge and urethritis. Abdominal pain also may be present. Trichomoniasis in pregnancy has been associated with premature rupture of membranes, preterm delivery, and low birth weight. In men, infection is often asymptomatic (90% to 95%), but urethritis may be present. The incubation period varies from 3 to 28 days.

Diagnosis and Differential

Diagnosis is based on finding the motile, flagellated organism on a saline wet preparation of vaginal discharge or in a spun urine specimen.

Emergency Department Care and Disposition

1. Metronidazole 2 grams PO in a single dose is the treatment of choice (alternatively, 500 milligrams PO twice daily for 7 days). Alternatively tinidazole, 2 grams PO single dose.

2. Metronidazole is a pregnancy category B drug, and it is the drug of choice for treating symptomatic pregnant patients. The CDC guidelines state that pregnant women may be treated with a single 2-gram dose of metronidazole.

Clinical Features

Treponema pallidum, a spirochete, causes syphilis. It enters the body through mucous membranes and nonintact skin. Syphilis occurs in 3 stages. The primary stage is characterized by the chancre (see Fig. 87-1), a single painless ulcer with indurated borders that develops after an incubation period of 21 days on the penis, vulva, or other areas of sexual contact (including the vagina or cervix). The primary chancre heals and disappears after 3 to 6 weeks. The secondary stage occurs several weeks after the chancre disappears. Rash and lymphadenopathy are the most common symptoms. The rash starts on the trunk, spreads to the palms and soles, and is polymorphous, most often dull red and papular (similar to that of Pityriasis rosacea), but it may also take on other forms such as psoriatic or pustular lesions. The rash is not pruritic. Constitutional symptoms are common, including fever, malaise, headache, and sore throat. Mucous membrane involvement (“mucous patches”) includes oral or vaginal lesions, and condyloma lata, which are flat, moist, wartlike growths, may occur at the perineum, anogenital region, or adjacent areas (thighs). This stage also resolves spontaneously. Latency refers to the period between stages during which a patient is asymptomatic. Any patient with secondary or latent syphilis who presents with neurologic symptoms or findings should have a lumbar puncture and cerebrospinal fluid testing for neurosyphilis. Late stage or tertiary syphilis, which is less common (classically found in 33% of untreated patients), occurs years after the initial infection and affects primarily the cardiovascular and neurologic systems. Specific manifestations include neuropathy (tabes dorsalis), meningitis, dementia, and aortitis with aortic insufficiency and thoracic aneurysm formation.

Diagnosis and Differential

Syphilis may be diagnosed in the early stages with dark-field microscopic identification of the treponemes from the primary chancre or secondary condyloma or oral lesions. Serologic tests include nontreponemal (VDRL and rapid plasma reagin) and treponemal (fluorescent treponemal antibody absorption test). Nontreponemal test results are positive about 14 days after the appearance of the chancre. There is a false positive rate of approximately 1% to 2% of the population. Treponemal tests are more sensitive and specific but harder to perform.

Emergency Department Care and Disposition

1. Syphilis in all stages remains sensitive to penicillin, which is the drug of choice: benzathine penicillin G 2.4 million units IM as a single dose. Latent or tertiary syphilis is treated as above with 3 weekly IM injections.

2. Doxycycline, 100 milligrams PO twice daily for 14 days or tetracycline, 500 milligrams 4 times daily for 14 days.

3. Intravenous high-dose penicillin is the only treatment with proven benefit for neurosyphilis (tertiary).

Clinical Features

Herpes simplex virus type 2 and, less often, type 1 cause genital herpes by invading mucosal surfaces or nonintact skin. In primary infections, clusters of painful pustules or vesicles on an erythematous base occur 7 to 10 days after contact with an infected person. These lesions ulcerate and may coalesce over the next 3 to 5 days, and in women a profuse watery vaginal discharge may develop. Tender inguinal adenopathy is usually present. Dysuria is common and may lead to frank urinary retention due to severe pain. Systemic symptoms are common in first infections and include fever, chills, headache, and myalgias. The untreated illness lasts 2 to 3 weeks and then heals without scarring. The virus remains latent in the body, however, and continues to be shed in urogenital secretions of asymptomatic patients, making transmission to partners possible. Recurrences occur in most patients (60% to 90%) but are usually briefer and milder without systemic symptoms.

Diagnosis and Differential

The diagnosis is usually clinical, based on the characteristic appearance. Viral cultures for herpes simplex virus taken from vesicles or early ulcers are more reliable than the Tzanck smear for intranuclear inclusions.

Emergency Department Care and Disposition

1. Treatment of choice for primary genital herpes is a 7- to 10-day course of acyclovir 400 milligrams PO 3 times daily, valacyclovir 1 gram PO twice daily, or famciclovir 1 gram PO twice daily.

2. In those cases severe enough to require hospitalization, treatment with intravenous acyclovir 5 to 10 milligrams/kilogram body weight every 8 hours IV may be given.

3. Treatment for episodes of recurrent genital herpes consist of a 5-day course of acyclovir 400 milligrams PO twice daily, valacyclovir 500 milligrams to 1 gram PO twice daily, or famciclovir 250 milligrams PO twice daily. If started at the onset of symptoms, antiviral therapy may reduce the severity and duration of the episode.

Clinical Features

Caused by Haemophilus ducreyi, a pleomorphic gram-negative bacillus, chancroid is more common in the tropics, but in recent years there has been a rise in cases in the United States, with epidemic outbreaks. Incubation is 4 to 10 days. A tender papule on an erythematous base appears on the external genitalia and then over 1 to 2 days erodes to become a painful purulent or pustular ulcer with irregular edges (see Fig. 87-3). Multiple ulcers may be present. The ulcers are usually 1 to 2 cm in diameter with sharp, undermined margins and are very painful. “Kissing lesions” may occur due to autoinoculation of adjacent skin. Tender inguinal adenopathy, usually unilateral, follows in 50% of untreated patients within 1 to 2 weeks, and these nodes may meet together to form a mass (bubo) that becomes necrotic, suppurates, and drains. Constitutional symptoms are rare.

Diagnosis and Differential

Diagnosis is usually clinical, with care to exclude syphilis. Sometimes the organism may be cultured from a swab of the ulcer or pus from a bubo, but special media are required.

Emergency Department Care and Disposition

1. Treatment regimens include azithromycin 1 gram PO as a single dose, ceftriaxone 250 milligrams IM as a single dose, erythromycin 500 milligrams PO 3 times a day for 7 days, or ciprofloxacin 500 milligrams PO twice daily for 3 days. Symptoms usually improve within 3 days, but large ulcers may require 2 to 3 weeks to heal.

2. Buboes may be aspirated to relieve pain from swelling but should not be excised.

Clinical Features

Three serotypes of C trachomatis are associated with lymphogranuloma venereum (LGV), which is endemic in other parts of the world but uncommon in the United States. The primary lesion, usually occurring 5 to 21 days after exposure, is a painless, small papule or vesicle (see Fig. 87-4) that may go unnoticed and heals spontaneously in a 2 to 3 days. After anal intercourse, primary LGV may present as painful mucopurulent or bloody proctitis. Several weeks to months after the primary lesion, painful inguinal adenopathy (unilateral in 60%) occurs. The nodes mat together to form a bubo (often with a purplish hue to the overlying skin) and often suppurate and form fistulae. “Groove sign,” an indentation across the bubo that parallels the inguinal ligament, may be seen. Systemic symptoms may include fever, chills, arthralgias, erythema nodosum, and, rarely, meningoencephalitis. Late sequelae include scarring; urethral, vaginal, and anal strictures; and occasionally lymphatic obstruction.

Diagnosis and Differential

Diagnosis is through serologic testing and culture of LGV from a lesion. A complement fixation titer for LGV greater than 1:64 is consistent with infection.

Emergency Department Care and Disposition

1. Doxycycline 100 milligrams PO twice daily for 21 days is the treatment of choice.

2. An alternative is erythromycin 500 milligrams PO 4 times daily for 21 days.