This section contains discussion and/or specific guidelines for
the following topics:
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
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
Return to top
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
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
Return to top
estimated 8.5% of couples in their childbearing years are infertile.
Chlamydia infections are suspected to be the
number 1 cause of preventable infertility.
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.
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. Reiterís
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.
Spectrum of Chlamydia trachomatis:
Asymptomatic pharyngeal carriage
Asymptomatic gastrointestinal tract carriage
Tubal factor infertility
Reiterís syndrome (rare)
Return to top
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 Skeneís gland
ducts, or the Bartholinís 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 manís 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.
Return to top
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.
Return to top
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 ďgivenĒ her something. She is taking birth
control pills and denies having missed any pills but is concerned about STDs.
Would a Gen-Probe test today be indicated? Why or why not?
answers found in Appendix)
Return to top