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Gonorrhea
is caused by the bacterium Neisseria
gonorrhoeae. It typically infects epithelia of the
urethra, cervix, rectum, pharynx, or eyes, causing irritation and
purulent discharge. Dissemination to skin and joints occurs infrequently.
Diagnosis is by culture or genetic methods. Several antibiotic regimens—oral
or parenteral—can be used.
N. gonorrhoeae is an aerobic, gram-negative diplococcus, transmission of which is almost always by sexual contact. Urethral and endocervical infections are most common, but infection also occurs in the pharynx or rectum after oral or anal intercourse. Transmission per episode of vaginal intercourse is about 20% from women to men but may be more efficient from men to women. Newborns can acquire conjunctival infection from the birth canal (see Infections in Neonates: Neonatal Conjunctivitis). Children may develop gonorrhea through sexual abuse.
In 10 to 20% of women, the infection ascends via the endometrium to the salpinges and pelvic peritoneum (pelvic inflammatory disease—see Vaginitis and Pelvic Inflammatory Disease (PID): Pelvic Inflammatory Disease (PID)). Chlamydia or enteric organisms may be causative as well. Endocervical gonorrhea is commonly accompanied by infection of the urethra, Skene's ducts, and Bartholin's glands, which may be symptomatic. In a small fraction of men, ascending urethritis progresses to unilateral epididymitis. Disseminated gonococcal infection (DGI) from hematogenous spread occurs in < 1% of cases, predominantly in women. DGI typically affects the skin, tendon sheaths, and joints. Pericarditis, endocarditis, meningitis, and perihepatitis occur rarely.
Concomitant infection with Chlamydia trachomatis occurs in 15 to 25% of heterosexual men and 35 to 50% of women.
Symptoms and Signs
About 10 to 20% of infected women and very few infected men are asymptomatic. About 25% of men have minimal symptoms.
Male urethritis has an incubation period from 2 to 14 days. Onset is usually marked by mild discomfort in the urethra, followed a few hours later by dysuria and a purulent discharge. Urinary frequency and urgency may develop as the disease spreads to the posterior urethra. Examination reveals a purulent, yellow-green urethral discharge, and the meatus may be inflamed.
Epididymitis usually causes unilateral scrotal pain, tenderness, and swelling. A secondary hydrocele may follow. Rarely, men develop abscesses of Tyson's and Littre's glands; periurethral abscesses; or infection of Cowper's glands, the prostate, and the seminal vesicles.
Cervicitis usually has an incubation period of < 10 days. Urethritis may occur concurrently. Symptoms range from mild to severe and include dysuria, frequency, and vaginal discharge. The cervix may be reddened and friable, with a mucopurulent or purulent discharge. Pus may be expressed from the urethra on pressure against the symphysis pubis or from Skene's ducts or Bartholin's glands. Rarely, infections in sexually abused prepubertal girls cause dysuria, purulent vaginal discharge, and vulvar irritation, erythema, and edema.
Pelvic
inflammatory disease (PID) occurs in 10 to 20% of infected women. It may include salpingitis, pelvic peritonitis, and pelvic abscesses and may produce lower abdominal discomfort, typically bilateral, dyspareunia, and marked tenderness on palpation of the abdomen, adnexa, and cervix.
Fitz-Hugh-Curtis
syndrome is gonococcal (or chlamydial) perihepatitis that occurs predominantly in women and produces right upper quadrant abdominal pain, fever, nausea, and vomiting, often mimicking biliary or hepatic disease.
Rectal
gonorrhea is usually asymptomatic. It occurs predominantly in homosexual men but also can occur in women who participate in anal sex, producing itching, purulent discharge, bleeding, tenesmus, and constipation, all of varying severity. Proctoscopy may show erythema or mucopurulent exudate on the rectal wall.
Gonococcal pharyngitis is uncommonly symptomatic but may cause sore throat. Since Neisseria meningitidis is often carried in the throat without causing symptoms or harm, the 2 organisms must be distinguished.
Disseminated
gonococcal infection (DGI, or arthritis-dermatitis syndrome) reflects bacteremia and typically presents with fever, malaise, migratory polyarthralgia, and skin lesions. Many patients develop tenosynovitis, typically in the flexor tendons of the wrist or the Achilles tendon. Skin lesions are small and slightly painful, with a red base; may be papular, pustular, or vesicular; and typically occur on the distal extremities. Genital gonorrhea, the usual source of disseminated infection, may be asymptomatic. DGI can mimic other disorders that cause fever, skin lesions, and polyarthritis (eg, the prodrome of hepatitis B infection or meningococcemia), some of which may produce genital symptoms (eg, reactive arthritis—see Joint Disorders: Reactive Arthritis).
Gonococcal
arthritis is a more focal form of DGI that results in a frank septic arthritis with effusion. Some patients have previous or coincident symptoms of DGI. Usually only 1 or 2 joints are involved, primarily the knees, ankles, wrists, and elbows. Onset is often acute, with fever, severe pain, and limitation of movement but may occur without constitutional symptoms. Infected joints are swollen, and the overlying skin may be warm and red.
Diagnosis
Diagnosis is by Gram stain, culture, or a number of commercially available genetic techniques. Confirmed cases should be reported to the public health system. Reporting is mandatory throughout the US. A serologic test for syphilis (STS) and a screen for chlamydia infection should be obtained.
Urethral samples are obtained by inserting a small swab about 2 to 4 cm into the urethra. Rectal and pharyngeal swabs for culture can be obtained with any sterile cotton-tipped swab. Endocervical or rectal swabs should be inserted at least 2 cm and rotated for 10 sec. Gram stain is sensitive and specific for samples from men with urethral discharge but not for samples from other sites or from women. Rectal and pharyngeal infections cannot be accurately evaluated by Gram stain. Culture requires an atmosphere with added CO2 and an enriched medium, such as the modified Thayer-Martin agar, containing antibiotics that selectively suppress normal flora.
For urethral and cervical infections, assays based on nucleic acid probes can detect gonococcal (and chlamydial) infections rapidly and reliably. If preceded by amplification (eg, PCR or ligase chain reaction), they can be used to detect infections using urine. This approach facilitates screening asymptomatic patients at high risk without invasive procedures to collect samples from genital sites. (See also the US Preventive Services Task Force's summary of recommendations regarding screening
for gonorrhea.)
In 30 to 40% of patients with DGI, blood cultures are positive in the 1st wk of illness. With septic arthritis, blood cultures are less often positive, but joint fluids are more often positive. Isolated, frank, acute arthritis in a sexually active patient requires joint aspiration to diagnose gonococcal infection. Fluid is usually purulent (WBCs > 20,000/μL). Cultures of joint fluid are positive in 40 to 50%, but organisms are rarely visible on Gram stain. PCR testing may be more sensitive but has not been evaluated.
Treatment
Uncomplicated gonococcal infection of the urethra, cervix, rectum, and pharynx is treated with a single dose of ceftriaxone 125 mg IM. For patients with documented severe allergic reactions to penicillins or cephalosporins, a single oral dose of azithromycin 2 g can be used. Spectinomycin 2 g IM is an effective alternative but is currently unavailable in the US. Fluoroquinolones are no longer recommended due to increasing resistance to this class of drugs. Patients are also empirically treated for chlamydia infection (see Sexually Transmitted Diseases (STD): Treatment), which is often asymptomatic or masked by symptoms of gonorrhea. A single 2-g oral dose of azithromycin is effective against both gonococci and chlamydia but frequently causes GI adverse effects and is not recommended.
DGI with gonococcal arthritis is initially treated parenterally with ceftriaxone 1 g IM or IV q 24 h, ceftizoxime 1 g IV q 8 h, cefotaxime 1 g IV q 8 h, or spectinomycin 2 g IM q 12 h. Parenteral therapy is continued for 24 to 48 h after clinical improvement and followed by 4 to 7 days of oral therapy with cefixime 400 mg bid.
For gonococcal arthritis, therapeutic joint drainage is usually not required. Initially the joint may be immobilized in a functional position. Passive range-of-motion exercises should be started as soon as possible. Once pain subsides, more active exercises, with stretching, active range of motion, and muscle strengthening, should begin. Over 95% of patients treated for gonococcal arthritis recover complete joint function. Because sterile joint effusions may persist for prolonged periods, an anti-inflammatory drug may be beneficial.
Posttreatment cultures are unnecessary if symptomatic response is adequate. However, for patients with symptoms for > 7 days, cultures are repeated with antimicrobial sensitivity testing. All patients with gonorrhea should abstain from sexual activity until treatment is completed. The patient's sexual contacts should be tested for gonorrhea and other STDs as appropriate, and if exposed within 2 wk, treated for gonorrhea presumptively (epidemiologic treatment).
Last full review/revision November 2005
Content last modified November 2007
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