STIs present a serious and increasing public health problem. They are caused by a variety of etiologic agents (Table 7.8). Some conditions, such as chlamydial and nongonococcal urethritis, have reached epidemic proportions. Although nongonococcal urethritis is a nonreportable infection in the United States, it is estimated that more than 2 million new cases occur each year. Manifestations of these infections range from the carrier state (with no symptoms) to infections with obvious symptoms such as cervicitis, conjunctivitis, endometritis, epididymitis, infertility, pharyngitis, proctitis, lymphogranuloma venereum, salpingitis, trachoma, urethritis, and, in the neonate, conjunctivitis and pneumonia.
Urethral, vaginal, and cervical swabs
Semen
Urine
Prostatic secretion
Tissue biopsy
Swabs of oral lesions
Blood for serologic tests
Viral isolation in tissue cell cultures
Specific serologic antibody assays and syphilis detection tests
Cytologic techniques, such as Papanicolaou (Pap) and Tzanck tests, to demonstrate giant cells associated with herpesvirus infection
Gram stain and bacterial culture; saline wet prep
ELISA and immunoperoxidase assay to detect etiologic agent
Fluorescein or enzyme-tagged monoclonal antibodies to detect and identify etiologic agents
DNA probe
Nucleic acid amplification test
Patients presenting with one STI may also be infected with other types of sexually transmitted pathogens.
Carriers with no symptoms are common.
Tracing and testing of sexual partners is a very important part of diagnosis and treatment.
The infection may recur if the patient is reinfected by the nontreated sexual partner.
Genital tract infections caused by sexually transmitted organisms in children are often the result of sexual abuse. Cultures should always be obtained, especially for Chlamydia, when required as legal evidence.
For suspected herpetic lesions, the virus is best recovered from the base of an active lesion. The older the lesion, the less likely it is to yield viable virus. Open the vesicle with a small-gauge needle or Dacron swab. Rub the base of the lesion vigorously to recover infected cells onto the swab, and place the swab in a viral transport medium. If large vesicles are present, aspirate material directly by needle and syringe. A separate swab can be collected for a Tzanck preparation (histology stain).
For dark-field examination (e.g., syphilis), cleanse the area around the lesion with sterile saline. Abrade the surface with sterile dry gauze until blood is expressed. Continue to blot until blood ceases; squeeze the area until serous fluid is expressed. Touch the material to a clean glass slide, add a cover slip, and examine the specimen immediately for motile spirochetes.
Complications of untreated STIs include ectopic (tubal) pregnancy, infertility, chronic pelvic pain, and poor pregnancy outcomes.