NM Department of Health Family Planning Program

Services and Clinics

Medical Overview

This section contains discussion and/or specific guidelines for the following topics:

• Etiology of Chlamydia trachomatis

• Epidemiology

• Clinical Manifestations

  • Females

  • Males

  • Table: Clinical Spectrum of Chlamydia trachomatis

• Gonorrhea

• Summary

• Case Study

Etiology

Chlamydia trachomatis (Ct) is a nonmotile, gram-negative bacterial pathogen with a two phase life cycle. Unable to synthesize its own adenosine triphosphate (ATP), the chlamydia organism requires an exogenous (host) source. The infectious form of the organism is referred to as the elementary body (EB) which attaches to and enters the host cell. After entering the host cell, the EBs begin their second life cycle as metabolically active reticulate bodies (RBs). The RBs use host-derived ATP to replicate by binary fission. Up to several hundred progeny are produced within a large cytoplasmic inclusion. These newly replicated RBs reorganize into the infectious EBs and are released by the host cell - thus completing the life cycle.

Within the Chlamydia trachomatis species, there are multiple serovars and serovariants with etiologic potential for disease pathology. Immunity following infection is thought to be type specific and only partially protective; therefore, recurrent infections are common.

In females, the initial site of infection is usually the endocervical columnar epithelia. Adolescents with columnar epithelial cells on the ectocervix and oral contraceptive pill (OCP) users are highly susceptible to infection. Cervical infections may resolve spontaneously or continue as a low-grade chronic infection with minimal signs of inflammation. Infections can ascend through the upper genital tract to involve the endometrium and fallopian tubes. The severity and the chronicity of chlamydia infections appear to be highly variable.

In males, infections usually remain localized to the urethra but can spread to cause epididymitis or prostatitis. Infections may resolve spontaneously but the natural course of untreated infection in men is not well known.

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Epidemiology

Chlamydia trachomatis is the most common bacterial sexually transmitted disease in the United States. An estimated 4 million new infections occur each year. Conservative estimates indicate that 1 in every 20 sexually active women of childbearing age and 1 in every 10 adolescent girls are infected with Ct. The prevalence of Chlamydia trachomatis infection in men ranges from 4% - 10% in asymptomatic populations and from 15% - 20% in young men attending STD clinics. Preliminary data from the Region VI Infertility Prevention Project indicate that prevalence rates in this region are comparable to these national estimates.

As many as 70% - 80% of women and up to 50% of men who are infected with Ct are asymptomatic. Because so many infected persons are asymptomatic, there is a large number of unidentified, infected individuals who are capable of transmitting the infection to their sexual partners. Complications of untreated chlamydia infection in adult women include pelvic inflammatory disease (PID), ectopic pregnancy, and tubal infertility. Without adequate treatment, approximately 20% - 50% of women infected with chlamydia develop PID. Among women with PID, inflammation and scarring will cause about 20% to become infertile, 6% - 9% to develop potentially fatal ectopic pregnancies, and 18% to suffer chronic and debilitating pelvic pain. Recent studies have reported that many adolescent females are at especially high risk for developing recurrent infections with as many as 38% developing recurrent infections within 3 years. The risk of developing serious sequelae such as ectopic pregnancy or infertility increases with successive Ct episodes. Chlamydia infections are also associated with a three to five fold increased risk of HIV infection via sexual transmission from an HIV-infected sex partner.

The risk of acquiring Ct infection from an infected partner has been difficult to ascertain as there is very limited data for single encounters with an infected person. However, a conservative estimate for the risk of infection is probably between 30% - 60% for a woman who has multiple contacts with an infected partner and somewhat lower for a man in comparable circumstances.

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Clinical Manifestations

An estimated 8.5% of couples in their childbearing years are infertile.  Chlamydia infections are suspected to be the number 1 cause of preventable infertility.

Females

Clinical manifestations in females can include cervicitis, urethritis, endometritis, PID, or abscess of the Bartholin glands.  Although the cervix is usually the primary site of infection, studies have shown that the urethra and rectum may be infected.  Acute endocervical infection is frequently characterized by mucopurulent cervicitis, cervical friability, culture-negative pyuria, and more than 10 polymorphonuclear leukocytes (PMNs) per microscopic field (x1,000) on gram stain of endocervical secretions with no GNIDC (gram negative intracellular diplococci).  Chlamydial infection can occasionally cause urethral syndrome defined as dysuria with or without pyuria in the absence of significant bacteriuria.  Endometritis is common in women infected with Ct, especially in the presence of mucopurulent cervicitis.  Endometritis may be symptomatic or clinically silent and can persist despite shedding of the endometrium with menses.  Symptoms usually include low-grade abdominal pain, cramping and bleeding between menstrual periods.  Symptoms of chlamydial PID can include dyspareunia, pelvic pain, fever, nausea, vomiting or other systemic manifestations.  Acute symptomatic chlamydial PID is more frequent in younger women.  More commonly, chlamydial PID is clinically chronic and associated with mild to moderate abdominal pain and less impressive tenderness on pelvic exam.  Unfortunately, such women may have significant tubal inflammation at laparoscopy.

A higher proportion of PID has been found to be attributable to Ct than to Neisseria gonorrhoeae.  Chlamydial infections also appear to cause more severe tubal immunopathology (for example tubal scarring) than other infections.  This is thought to be a consequence of the greater chronicity and insidious character of Ct infections compared with more acute infections like gonorrhea.  Silent and untreated salpingitis is a major cause of infertility.  More than 50% of women with documented tubal occlusion report no history of PID but do have serologic evidence of previous chlamydial infection.  Similarly, ectopic pregnancies have been associated with previous chlamydial infections. 

Pregnant women with chlamydial infections appear to be at increased risk for adverse outcomes of pregnancy and postpartum PID.  Some studies have reported increased outcomes associated with stillbirths, preterm deliveries, and premature rupture of the membranes.  Although, there is not a great deal of evidence to associate these perinatal outcomes with Chlamydia trachomatis infections, the diagnosis and treatment of women who are infected with Ct during pregnancy is obviously beneficial.  An infant born to a woman with chlamydial infection has about a 70% chance of being infected.  Approximately 30% of infants born to infected women develop neonatal inclusion conjunctivitis and 15% develop pneumonia with others developing otitis media or becoming asymptomatic carriers.

 Males                                                

As mentioned earlier, approximately 50% of chlamydial infections in men are asymptomatic.  The most common signs and symptoms are those associated with urethritis and include urethral discharge and/or dysuria.  Approximately 30 to 50% of all cases of nongonococcal urethritis (NGU) are caused by Ct.  Epididymitis in young (under 35), sexually active men is often due to chlamydial or gonococcal infections.  The prevalence of chlamydial infections in homosexual and bisexual men is about one-third of that reported in heterosexual men.  Among homosexual men seen in STD clinics, some 4 to 8% have chlamydial infections of the rectum.  Reiter’s syndrome, an immune-mediated systemic illness occurring more often in men than women, can occur about one month after genital infection.  This syndrome is characterized by arthritis, conjunctivitis, and urethritis.

  Clinical Spectrum of Chlamydia trachomatis:

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Gonorrhea

The gonococcus that causes gonorrhea, Neisseria gonorhoeae, is seen in pairs and appears as bean or kidney-shaped, gram-negative intracellular diplococci.  The gonococcus grows best in warm, moist, nonacidic columnar or transitional epithelium (such as the urethra, cervix, and rectum).

The endocervical canal is the primary site of gonococcal infection in women.  The incubation period is uncertain and seems more variable than in men.  Most women infected with the gonococcus remain asymptomatic.  The women who develop local symptoms do so within 10 days of infection.  The most common manifestations in women include increased vaginal discharge, dysuria, and intermenstrual uterine bleeding.  These symptoms may occur alone or in combination and may range from barely noticeable to severe.  The results of a physical examination may be normal, but many women with gonorrhea have abnormalities of the cervix, including purulent or mucopurulent endocervical discharge, erythema, friability, and edema.  Purulent or mucoid exudate may be expressed from the urethra, the Skene’s gland ducts, or the Bartholin’s gland ducts.  Signs and symptoms in women with gonorrhea are sometimes difficult to assess because of the prevalence of coexisting infection with Ct and other STDs.

In males the average incubation period is 3-5 days, but may range from 0-30 days.  Although the gonococcus invades the urethra to a depth of about 2 inches, the client may have no symptoms and thus may not believe he is infected.  Symptoms include a scanty to profuse mucopurulent discharge, usually with painful and frequent urination.  The head of the penis may become swollen and sore.

Only a few countries have reporting systems that allow an accurate estimate of the true incidence of gonorrhea.  In the United States, annually reported gonorrhea cases declined for the fifth consecutive year, from 419, 470 in 1994 to 324,901 in 1997.  Rates decreased from 162.9 cases per 100,000 population to 123.6 per 100, 000.  Of the reported cases, 51.9 percent are in men, a proportion that has not varied much in recent years.  The incidence of gonorrhea is partly dependent on age.  Of reported cases in the United States 1994-1997, 75% occurred in person 15-29 years old.  Additional demographic risk factors for gonorrhea include race, low socioeconomic level, unmarried marital status, urban residence, early onset of sexual activity, male homosexuality, and history of gonorrhea.  The incidence of gonorrhea in the United States is highest in late summer and lowest in winter and early spring.

Medical and laboratory aspects of gonorrhea are continually changing.  Treatment guidelines have been adjusted several times since penicillin-resistant  organisms were first identified in 1976.  Uncomplicated gonococcal infection is gonorrhea that remains localized at the site(s) of initial inoculation and does not cause disabling symptoms.  Eighty to 90% of infections remain uncomplicated when clients are treated promptly, but complications develop frequently in clients who do not receive prompt, effective therapy.

The rate of transmission depends on the anatomic sites infected, the sites exposed, and the number of exposures.  A man’s risk of acquiring a urethral infection after a single episode of vaginal intercourse with an infected woman is about 20 percent, but the risk rises to 60-80 percent after four exposures.  In women who have multiple exposures to men with gonorrheal urethritis, the prevalence of infection is 50-90%.  The rate of transmission from male to female from a single exposure is probably higher than from female to male.  Symptoms and behavior also influence the transmission of gonorrhea.  Many cases detected through screening and contact referral programs are asymptomatic or only mildly symptomatic.  Asymptomatic infected sex partners often deny they are infected and may continue to spread the disease.  Therefore it is important to motivate all contacts of gonorrhea clients to get an examination and treatment.  About 40% of asymptomatic men and many asymptomatic women have physical findings compatible with gonorrhea. 

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Summary

The Chlamydia trachomatis organism is an obligate, intracellular bacteria that preferentially infects columnar or transitional epithelium.  The Neisseria gonorrhoeae organism is a bean or kidney-shaped, gram-negative intracellular diplococci which also grows best in columnar or transitional epithelium.

Infections are often asymptomatic and chronic with re-infection common.

In females, the cervix is the most common primary site of infection.

In males, the most common signs and symptoms are associated with urethritis.

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Case Study

Case 1:  A 24 year old white female presents to your clinic.  She states that she had unprotected sex last night with a new partner and is now worried that he might have “given” her something.  She is taking birth control pills and denies having missed any pills but is concerned about STDs.

Question:  Would a Gen-Probe test today be indicated?  Why or why not?

 (Case Study answers found in Appendix)

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