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Infections in the pelvic organs and surrounding structures compose a heterogeneous group of diseases. They primarily affect sexually active women and men. Many of the pathogens implicated are sexually transmitted, so an important facet of management is partner notification and treatment, as well as patient education regarding safe sexual practices. Among sexually transmitted infections, major syndromes that will be discussed are genital ulcer disease, vaginitis, cervicitis, pelvic inflammatory disease (PID), urethritis, prostatitis, and epididymitis.

Two terms used to describe these infections are "sexually transmitted infections" (STI) and "sexually transmitted diseases" (STD). The distinction is based on the observation that many of these infections are asymptomatic and are detected by laboratory findings but, nevertheless can serve as a source of infection for others. The term STI includes those infections that are both symptomatic and asymptomatic whereas the term STD refers to those that are symptomatic. Note that these two terms are often used interchangeably.

Important bacterial causes of STI include Chlamydia trachomatis, Neisseria gonorrhoeae, and Treponema pallidum. Other bacterial causes include Haemophilus ducreyi, Mycoplasma genitalium, Klebsiella granulomatis, and Gardnerella vaginalis. Important viral causes of STI include human papilloma virus, human immunodeficiency virus, and herpes simplex virus-2. Other viral causes include hepatitis B virus, hepatitis C virus, Zika virus, and Ebola virus. The protozoan, Trichomonas vaginalis and the ectoparasite, Phthirus pubis (pubic louse) are also sexually transmitted.

Some of the organisms described in this chapter, such as Treponema pallidum, Neisseria gonorrhoeae, Chlamydia trachomatis, and herpes simplex virus 2, are transmitted from the mother to the fetus. The acronym TORCHES is used to describe certain important fetal or newborn infections acquired from the mother. There are several versions of this acronym. The following is a commonly used one: T = Toxoplasma; O = other (including parvovirus, human immunodeficiency virus [HIV], and Zika virus); R = rubella; C = cytomegalovirus; HE = herpes simplex virus 2; and S = syphilis. A more complete list of organisms vertically transmitted from mother to child can be found in Part 12, Table XII–10.



Genital ulcer disease manifests as a breach in the skin or mucosa of the genitalia, usually caused by a sexually transmitted infection. Of these infections, herpes simplex virus type 2 (HSV-2) is the most common etiology in most geographic areas, followed by syphilis and chancroid. The most important noninfectious cause is Behçet’s disease.


The mechanisms by which ulcers are produced by pathogens are incompletely understood, and there are different mechanisms of injury depending on the pathogen. In chancroid, a cytotoxin secreted by Haemophilus ducreyi may be important in epithelial cell injury.

Clinical Manifestations

Although the ...

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