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Infectious Diseases
Sexually Transmitted Diseases (STDs)
Chlamydial, Mycoplasmal, and Ureaplasmal Infections
Symptoms and Signs
Diagnosis
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Chlamydial, Mycoplasmal, and Ureaplasmal Infections

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Sexually transmitted urethritis, cervicitis, proctitis, and pharyngitis not due to gonorrhea are caused predominantly by chlamydiae and infrequently by mycoplasmas or Ureaplasma sp. Chlamydiae may also cause salpingitis, epididymitis, perihepatitis, neonatal conjunctivitis, and infant pneumonia. Untreated chlamydial salpingitis can become chronic, causing minimal symptoms but having serious consequences. Diagnosis is by culture, immunoassay for antigens, or genetic methods. Treatment is with single-dose azithromycin or a week of ofloxacin, levofloxacin, erythromycin, or a tetracycline.

Several organisms can cause nongonococcal sexually transmitted cervicitis in women and urethritis, proctitis, and pharyngitis in both sexes. These organisms include Chlamydia trachomatis (responsible for about 50% of such cases of urethritis and most cases of mucopurulent cervicitis), Mycoplasma genitalium, Ureaplasma urealyticum, and Trichomonas vaginalis (see Sexually Transmitted Diseases (STDs): Trichomoniasis). Chlamydiae may also cause lymphogranuloma venereum (see Sexually Transmitted Diseases (STDs): Lymphogranuloma Venereum (LGV)). The imprecise terms nonspecific “urethritis” and “nongonococcal urethritis” have been replaced by terms that specify the causative organism.

Symptoms and Signs

Men develop symptomatic urethritis after a 7- to 28-day incubation period, usually beginning with mild dysuria, discomfort in the urethra, and a clear to mucopurulent discharge. Discharge may be slight, and symptoms may be mild but are frequently more marked early in the morning; then, the urethral meatus is often red and blocked with dried secretions, which may also stain underclothes. Occasionally, onset is more acute, with dysuria, frequency, and a copious, purulent discharge that simulates gonococcal urethritis. Infection may progress to epididymitis. After rectal or orogenital contact with an infected person, proctitis or pharyngitis may develop.

Women are usually asymptomatic, although vaginal discharge, dysuria, increased urinary frequency and urgency, pelvic pain, dyspareunia, and symptoms of urethritis may occur. Cervicitis with yellow, mucopurulent exudate and cervical ectopy (expansion of the red endocervical epithelium onto the vaginal surfaces of the cervix) are characteristic. Pelvic inflammatory disease (salpingitis and pelvic peritonitis) may cause lower abdominal discomfort (typically bilateral) and marked tenderness when the abdomen, adnexa, and cervix are palpated. Fitz-Hugh-Curtis syndrome (perihepatitis) may cause right upper quadrant pain, fever, and vomiting.

Chlamydiae may be transferred to the eye, causing acute conjunctivitis.

Reactive arthritis (see Joint Disorders: Reactive Arthritis) caused by immunologic reactions to genital and intestinal infections is an infrequent complication of chlamydial infections in adults. Reactive arthritis sometimes causes skin and eye lesions and noninfectious recurrent urethritis.

Photographs

Reactive Arthritis (Keratoderma Blennorrhagicum)

Reactive Arthritis (Keratoderma Blennorrhagicum)
Photographs

Reactive Arthritis (Conjunctivitis)

Reactive Arthritis (Conjunctivitis)
Photographs

Reactive Arthritis (Balanitis)

Reactive Arthritis (Balanitis)

Infants born to women with chlamydial cervicitis may develop chlamydial pneumonia or ophthalmia neonatorum (neonatal conjunctivitis—see Infections in Neonates: Neonatal Conjunctivitis).

Diagnosis

  • Nucleic acid detection tests of cervical or urethral exudate or urine

Chlamydial, mycoplasmal, or ureaplasmal infection is suspected in patients with symptoms of urethritis, salpingitis, cervicitis, or unexplained proctitis, but similar symptoms can also result from gonococcal infection. If clinical evidence for urethritis is uncertain, finding ≥ 5 WBCs/high-power field in a urine sample confirms the diagnosis. Examination of first-voided, morning samples is most sensitive.

Samples of cervical or male urethral exudates are obtained to check for chlamydia. Nucleic acid–based tests (NAT) for chlamydial DNA may be done on nonamplified samples or may use one of several nucleic acid amplification techniques. Tests are usually done on swab samples, but amplified NAT tests are highly sensitive and specific and can also be done on urine, eliminating the need for doing an uncomfortable swab of the urethra or cervix. Amplification techniques should be routinely used in patients at high risk (eg, unprotected sex with new or multiple partners, history of prior sexually transmitted disease [STD], exchanging sex for drugs or money). Because gonococcal infection sometimes coexists, testing should also be done for that organism.

Detection of mycoplasmas and Ureaplasma sp is currently impractical in routine practice.

In the US, confirmed cases of chlamydial infection, gonorrhea, and syphilis must be reported to the public health system. A serologic test for syphilis (STS) should be done.

Screening: Urine testing using nucleic acid amplification tests (NAAT) is especially useful for screening asymptomatic people at high risk of STDs because genital examination is not necessary. People who should be screened include

  • People with a history of a previous STD
  • People with high-risk behaviors
  • Sexually active adolescents and young adults < 24 yr
  • Pregnant women < 24 yr

(See also the US Preventive Services Task Force's summary of recommendations regarding screening for chlamydial infection.)

Treatment

  • Oral antibiotics (various)
  • Treatment of sex partners

Uncomplicated documented or suspected chlamydial, ureaplasmal, or mycoplasmal infections are treated with one of the following:

  • A single dose of azithromycinSome Trade Names
    ZITHROMAX
    Click for Drug Monograph
    1 g po
  • DoxycyclineSome Trade Names
    PERIOSTAT
    VIBRAMYCIN
    Click for Drug Monograph
    100 mg po bid for 7 days
  • ErythromycinSome Trade Names
    ERY-TAB
    ERYTHROCIN
    Click for Drug Monograph
    base 500 mg po qid for 7 days
  • OfloxacinSome Trade Names
    FLOXIN
    Click for Drug Monograph
    300 mg po bid for 7 days
  • LevofloxacinSome Trade Names
    IQUIX
    LEVAQUIN
    QUIXIN
    Click for Drug Monograph
    500 mg po once/day for 7 days

For pregnant women, azithromycinSome Trade Names
ZITHROMAX
Click for Drug Monograph
1 g po once should be used.

These regimens do not reliably treat gonorrhea, which coexists in many patients with chlamydial infections. Therefore, treatment should usually include a cephalosporin, such as a single dose of ceftriaxoneSome Trade Names
ROCEPHIN
Click for Drug Monograph
125 mg IM.

Patients who relapse (about 10%) are usually coinfected with microbes that do not respond to antichlamydial therapy, or they were reinfected since treatment. They may require further diagnostic evaluation and repeated or longer (21 to 28 days) courses, and their current sex partners should be treated. Patients should abstain from sexual intercourse until they and their partners complete treatment.

If chlamydial genital infections are untreated, symptoms and signs subside within 4 wk in about two thirds of patients. However, in women, asymptomatic cervical infection may persist, resulting in chronic endometritis, salpingitis, or pelvic peritonitis and their sequelae—pelvic pain, infertility, and increased risk of ectopic pregnancy. Because chlamydial infections can have serious long-term consequences for women, even when symptoms are mild or absent, detecting the infection in women and treating them and their male sex partners is crucial.

Last full review/revision November 2008 by J. Allen McCutchan, MD, MSc

Content last modified February 2012

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