Sexually Transmitted Infections

Introduction

The transmission of certain infectious diseases occurs most efficiently via contact of mucous membranes, and therefore, are commonly spread by sexual contact. Early lesions mainly occur on the genitalia and therefore the urologist is the first physician to assess a patient with a sexually transmitted infection (STI). Urologists play an important role in the detection, treatment, and prevention of STIs.If left untreated,STIs may have devastating local and systemic consequences.

CDC estimates that approximately 19 million new infections occur each year.1 People at high risk for contracting sexually transmitted diseases are young adults between the ages of 15 and 24. Risk factors for contracting an STI include new or multiple sex partners, unprotected sex,illegal drug use,commercial sex work, and previous history of STI. Sexually transmitted infections also rank among the top five risks of international travelers.2

STIs Associated with Genital Ulcers

Genital herpes, syphilis, chancroid, and lymphogranuloma venereum (LGV) are often clinically characterized by the genital ulcer that is associated with them. Of these STIs, genital herpes is by far the most common followed by syphilis and chancroid. LGV is rare in the United

States but still prevalent in parts of Africa, Asia, South America, and the Caribbean.3

The specificity for clinical diagnosis of genital ulcer disease is high (94–98%) but sensitivity is low (31–35%).4 The differential diagnosis of genital ulcers includes conditions such as Behcet’s syndrome, drug reactions, erythema multiforme, Crohn’s disease,lichen planus,amebiasis,trauma, and carcinoma. If ulcers do not respond to therapy or appear unusual, a biopsy should be performed. The etiologic agent, classic description of the ulcer, associated lymphadenopathy, and CDC-recommended confirmatory tests are summarized in Table 25.1. CDC-recommended treatment guidelines and other important factors that the treating physician should consider are summarized in Tables 25.2 and 25.3.

Herpes Simplex Virus

Diagnosis

Herpes simplex virus type 2 (HSV-2) is the principle cause of genital herpes although HSV-1 now accounts for at least 50% of first episodes in the United States, Canada, and several European countries.5 HSV-1 is responsible for common cold sores, but can be transmitted to the genitals through oral secretions during oral-genital sex. It is important to educate patients that asymptomatic viral shedding may account for more than 75% of viral transmission and is more likely during the 3–12 months period following initial clinical presentation.6

1.consider screening for HiV, Hepatitis B and c, gonorrhea, and chlamydia

2.caution patient about Jarisch-Herxheimer reaction

3.check nontreponemal antibody titers at 6 and 12 months

1.Examine sexual partner and treat in case of sexual relations within 30 days

2.inguinal buboes may require incision and drainage to prevent ulceration

Primary infection manifests with painful ulcers of the genitalia or anus, and bilateral painful inguinal adenopathy. The initial infection is often associated with constitutional flu-like symptoms. A group of vesicles on an erythematous base that does not follow a neural distribution is pathognomonic for herpes simplex. Lesions may be present in the urethra. Sacral radiculomyelopathy is a rare manifestation of primary infection that has a greater association with primary anal HSV. Recurrent episodes are generally less severe than the primary infection and involve only ulceration of the genital or anal area. Genital lesions, especially urethral lesions,may cause transient urinary retention in women. Severe complications of herpes include pneumonitis, disseminated infection, hepatitis, meningitis, and encephalitis.

Diagnosis should be confirmed with laboratory verification because most patients present with atypical lesions. Women especially, may present with fissures,abrasions,or itching.7 Viral subtyping is important for prognosis and counseling, as HSV-2 will have a greater number of recurrences within the first year than HSV-1. HSV-1 rarely recurs after the first year while the rate of HSV-2 recurrence decreases but slowly.8 The use of cytologic detection of cellular changes of HSV infection (i.e., Tzanck preparation and Pap smears) is insensitive, nonspecific, and no longer recommended.

Viral culture is generally the preferred method of diagnosis because it is relatively inexpensive and highly specific. To obtain a specimen for viral culture, vesicles should be gently unroofed with a clean needle and then swabbed at the base of the lesion. The specimen should be placed directly into the viral culture media and transported

quickly to the laboratory. The sensitivity ranges substantially depending on whether it is the primary infection or a recurrence, and the stage of the lesion.Viral load is highest when the lesion is vesicularandduringprimaryinfection.Therefore, viral culture has the highest sensitivity at these times and declines sharply as the lesion heals.

An alternative to viral culture is quantitative real-time polymerase chain reaction (PCR) for HSV DNA. Increasing evidence suggests that PCR is a faster and more sensitive diagnostic method, but its implementation has been limited by concerns over contamination and cost.9,10

Type-specific HSV serologic assays identify antibodies to HSV glycoproteins G-1 and G-2.11 These tests may also be able to identify recently acquired versus established HSV infection based on antibody avidity.12 They may be useful for patients with recurrent genital symptoms or atypical symptoms with negative HSV cultures; a clinical diagnosis of genital herpes without laboratory confirmation; or for patients with a partner with genital herpes.

Treatment

Oral antiviral therapies approved for treatment include oral acyclovir, valacyclovir, and famciclovir. Topical antiviral medications are not effective. Recurrences can be treated with an episodic or suppressive approach. When used for episodic treatment, treatment must be initiated during the prodrome or within 1 day of the onset of lesions. Daily suppressive therapy has been shown to prevent 80% of recurrences and is an option for patients who suffer from frequent