1236 PART 5 Infectious Diseases
that show a porin-specific TH2-type response could traffic to mucosal
surfaces and play a role in immune protection against the disease. Few
data clearly indicate that protective immunity is acquired from a previous gonococcal infection, although bactericidal and opsonophagocytic
antibodies to porin and LOS may offer partial protection. On the other
hand, women who are infected and acquire high levels of antibody to
another outer-membrane protein, Rmp (reduction modifiable protein,
formerly called protein III), may be especially likely to become reinfected with N. gonorrhoeae because Rmp antibodies block the effect
of bactericidal antibodies to porin and LOS. Rmp shows little, if any,
interstrain antigenic variation; therefore, Rmp antibodies potentially
may block antibody-mediated killing of all gonococci. The mechanism
of blocking has not been fully characterized, but Rmp antibodies may
noncompetitively inhibit binding of porin and LOS antibodies because
of the proximity of these structures in the gonococcal outer membrane.
In male volunteers who have no history of gonorrhea, the net effect of
these events may influence the outcome of experimental challenge with
N. gonorrhoeae. Because Rmp bears extensive homology to enterobacterial OmpA and meningococcal class 4 proteins, it is possible that
these blocking antibodies result from prior exposure to cross-reacting
proteins from these species and also play a role in first-time infection
with N. gonorrhoeae.
Gonococcal Resistance to Antimicrobial Agents It is no
surprise that N. gonorrhoeae, with its remarkable capacity to alter its
antigenic structure and adapt to changes in the microenvironment,
has become resistant to numerous antibiotics. The first effective agents
against gonorrhea were the sulfonamides, which were introduced in
the 1930s and became ineffective within a decade. Penicillin was then
used as the drug of choice for the treatment of gonorrhea. By 1965, 42%
of gonococcal isolates had developed low-level resistance to penicillin
G. Resistance due to the production of penicillinase arose later.
Gonococci become fully resistant to antibiotics either by chromosomal mutations or by acquisition of R factors (plasmids). Two
types of chromosomal mutations have been described. The first
type, which is drug specific, is a single-step mutation leading to highlevel resistance. The second type involves mutations at several chromosomal loci that combine to determine the level as well as the pattern of
resistance. Strains with mutations in chromosomal genes were first
observed in the late 1950s. As recently as 2007, chromosomal mutations accounted for resistance to penicillin, tetracycline, or both in
~16% of strains surveyed in the United States.
β-Lactamase (penicillinase)–producing strains of N. gonorrhoeae
(PPNG) carrying β-lactamase plasmids had rapidly spread worldwide
by the early 1980s. N. gonorrhoeae strains with plasmid-borne tetracycline resistance (TRNG) can mobilize some β-lactamase plasmids,
and PPNG and TRNG occur together, sometimes along with strains
exhibiting chromosomally mediated resistance (CMRNG). Penicillin,
ampicillin, and tetracycline are no longer reliable for the treatment of
gonorrhea and should not be used.
Quinolone-containing regimens also were recommended for treatment of gonococcal infections; the fluoroquinolones offered the advantage of antichlamydial activity when administered for 7 days. However,
quinolone-resistant N. gonorrhoeae (QRNG) appeared soon after
these agents were first used to treat gonorrhea. QRNG is particularly
common in the Pacific Islands (including Hawaii) and Asia, where, in
certain areas, all gonococcal strains are now resistant to quinolones.
At present, QRNG is also common in parts of Europe and the Middle
East. In the United States, QRNG has been identified in all areas but
predominantly in states on the Pacific coast, where resistant strains
were first seen. Alterations in DNA gyrase and topoisomerase IV have
been implicated as mechanisms of fluoroquinolone resistance.
Resistance to spectinomycin, which has been used in the past as an
alternative agent, has been reported. Because this agent usually is not
associated with resistance to other antibiotics, spectinomycin can be
reserved for use against multidrug-resistant strains of N. gonorrhoeae.
Nevertheless, outbreaks caused by strains resistant to spectinomycin
have been documented in Korea and England when the drug has been
used for primary treatment of gonorrhea.
Third-generation cephalosporins have remained highly effective as
single-dose therapy for gonorrhea, but the recent isolation of strains
highly resistant to ceftriaxone (minimal inhibitory concentrations [MICs],
2 μg/mL) in Japan and some European countries is cause for concern.
Even though the MICs of ceftriaxone against certain strains may reach
0.015–0.125 μg/mL (higher than the MICs of 0.0001–0.008 μg/mL for fully
susceptible strains), these levels are greatly exceeded in the blood, the
urethra, and the cervix when the routinely recommended parenteral
dose of ceftriaxone is administered. The rising MICs of oral cefixime
(the previously recommended alternative oral third-generation cephalosporin) against N. gonorrhoeae, combined with this drug’s limited
capacity to reach levels sufficiently higher than MICs in the blood, the
urethra, the cervix, and especially the pharynx, have resulted in the
removal of cefixime from the list of first-line agents for treatment of
uncomplicated gonorrhea. N. gonorrhoeae strains with reduced susceptibility to ceftriaxone and cefixime (i.e., cephalosporin-intermediate/
resistant strains) contain mutations in (1) the penA allele, which is the
principal resistance determinant and encodes a penicillin-binding protein (PBP2) whose sequence can differ in up to 60–70 amino acids from
that of wild-type PBP2; (2) the multiple transferable resistance regulator
(mtrR) gene that results in increased drug efflux through the MtrCDE
efflux pump; and (3) penB, which decreases drug influx through PorB.
Resistance to azithromycin can result from alterations of the ribosomal binding target by azithromycin and—as with cephalosporins—
the over- and underexpression of efflux and influx systems. Combined
resistance to cephalosporins and azithromycin has been reported in
several instances throughout the world.
■ CLINICAL MANIFESTATIONS
Gonococcal Infections in Men Acute urethritis is the most common clinical manifestation of gonorrhea in male patients. The usual
incubation period after exposure is 2–7 days, although the interval can
be longer and most men remain asymptomatic. Strains of the PorB.1A
serotype tend to cause a greater proportion of cases of mild and
asymptomatic urethritis than do PorB.1B strains. When they occur,
urethral discharge and dysuria, usually without urinary frequency or
urgency, are the major symptoms. The discharge initially is scant and
mucoid but becomes profuse and purulent within a day or two. Gram’s
staining of the urethral discharge may reveal PMNs and gram-negative
intracellular monococci and diplococci (Fig. 156-1). The clinical manifestations of gonococcal urethritis are usually more severe and overt
than those of nongonococcal urethritis, including urethritis caused by
Chlamydia trachomatis (Chap. 189); however, exceptions are common,
and it is often impossible to differentiate the causes of urethritis on
clinical grounds alone. The majority of cases of urethritis seen in the
United States today are not caused by N. gonorrhoeae and/or C. trachomatis. Although a number of other organisms may be responsible,
many cases do not have a specific etiologic agent identified. Certain
clones of Neisseria meningitidis, the second member of the pathogenic
FIGURE 156-1 Gram’s stain of urethral discharge from a male patient with
gonorrhea shows gram-negative intracellular monococci and diplococci. (Source:
© All rights reserved. Canadian Guidelines on Sexually Transmitted Infections.
Public Health Agency of Canada, modified 2020. Adapted and reproduced with
permission from the Minister of Health, 2021.)
1237CHAPTER 156 Gonococcal Infections
Neisseria species, have been associated with urethritis in men who have
sex with men (MSM) in Europe and in heterosexual men in the southern and midwestern United States.
Most symptomatic men with gonorrhea seek treatment and cease
to be infectious. The remaining men, who are largely asymptomatic,
accumulate in number over time and constitute about two-thirds of all
infected men at any point in time; together with men incubating the
organism who shed the organism but are asymptomatic, they serve as
the source of spread of infection. Before the antibiotic era, symptoms
of urethritis persisted for ~8 weeks. Epididymitis is now an uncommon
complication, and gonococcal prostatitis occurs rarely, if at all. Other
unusual local complications of gonococcal urethritis include edema
of the penis due to dorsal lymphangitis or thrombophlebitis, submucous inflammatory “soft” infiltration of the urethral wall, periurethral
abscess or fistula, inflammation or abscess of Cowper’s gland, and seminal vesiculitis. Balanitis may develop in uncircumcised men.
Gonococcal Infections in Women • GONOCOCCAL CERVICITIS
Mucopurulent cervicitis is a common STI diagnosis in American
women and may be caused by N. gonorrhoeae, C. trachomatis, and
other organisms, including Mycoplasma genitalium (Chap. 188).
Cervicitis may coexist with candidal or trichomonal vaginitis. N. gonorrhoeae primarily infects the columnar epithelium of the cervical os.
Bartholin’s glands occasionally become infected.
Women infected with N. gonorrhoeae usually develop symptoms.
However, women who either remain asymptomatic or have only minor
symptoms may delay seeking medical attention. These minor symptoms may include scant vaginal discharge issuing from the inflamed
cervix (without vaginitis or vaginosis per se) and dysuria (often without urgency or frequency) that may be associated with gonococcal
urethritis. Although the incubation period of gonorrhea is less well
defined in women than in men, symptoms usually develop within
10 days of infection and are more acute and intense than those of
chlamydial cervicitis.
The physical examination reveals a mucopurulent discharge
(mucopus) issuing from the cervical os or a reddened (inflamed) cervix even in the absence of reported symptoms. Because Gram’s stain
is not sensitive for the diagnosis of gonorrhea in women, specimens
should be submitted for culture or a nonculture assay (see “Laboratory
Diagnosis,” below). Edematous and friable cervical ectopy and endocervical bleeding induced by gentle swabbing are more often seen in
chlamydial infection. Gonococcal infection may extend deep enough
to produce dyspareunia and lower abdominal or back pain. In such
cases, it is imperative to consider a diagnosis of pelvic inflammatory
disease (PID) and to administer treatment for that disease (Chaps. 136
and 189).
N. gonorrhoeae may also be recovered from the urethra and rectum
of women with cervicitis, but these are rarely the only infected sites.
Urethritis in women may produce symptoms of internal dysuria, which
is often attributed to “cystitis.” Pyuria in the absence of bacteriuria
visible on Gram’s stain of unspun urine, accompanied by urine cultures that fail to yield >102
colonies of bacteria usually associated with
urinary tract infection, signifies the possibility of urethritis usually
due to C. trachomatis. Urethral infection with N. gonorrhoeae also may
occur in this context, but in this instance, urethral cultures are usually
positive.
GONOCOCCAL VAGINITIS The vaginal mucosa of healthy women
is lined by stratified squamous epithelium and is rarely infected by
N. gonorrhoeae. However, gonococcal vaginitis can occur in anestrogenic women (e.g., prepubertal girls and postmenopausal women),
in whom the vaginal stratified squamous epithelium is often thinned
down to the basilar layer, which can be infected by N. gonorrhoeae.
The intense inflammation of the vagina makes the physical (speculum
and bimanual) examination extremely painful. The vaginal mucosa
is red and edematous, and an abundant purulent discharge is often
present. Infection in the urethra and in Skene’s and Bartholin’s glands
often accompanies gonococcal vaginitis. Inflamed cervical erosion or
abscesses in nabothian cysts may also occur. Coexisting cervicitis may
result in pus in the cervical os.
Anorectal Gonorrhea Because the female anatomy permits the
spread of cervical exudate to the rectum, N. gonorrhoeae is sometimes
recovered from the rectum of women with uncomplicated gonococcal
cervicitis. The rectum is the sole site of infection in only 5% of women
with gonorrhea. Such women are usually asymptomatic but occasionally have acute proctitis manifested by anorectal pain or pruritus,
tenesmus, purulent rectal discharge, and rectal bleeding. Among MSM,
the frequency of gonococcal infection, including rectal infection, fell by
≥90% throughout the United States in the early 1980s, A resurgence of
gonorrhea among MSM has been documented in several cities since
the 1990s, the estimated rates of reported cases having more than doubled in a recent 3-year period. Gonococcal isolates from the rectum of
MSM tend to be more resistant to antimicrobial agents than are gonococcal isolates from other sites. Gonococcal isolates with a mutation
in mtrR or in the promoter region of the gene that encodes for this
transcriptional regulator develop increased resistance to antimicrobial
hydrophobic agents such as bile acids and fatty acids in feces and thus
are found with increased frequency in MSM. This situation may have
been responsible for higher rates of failure of treatment for rectal gonorrhea with older regimens consisting of penicillin or tetracyclines.
Pharyngeal Gonorrhea Pharyngeal gonorrhea is usually mild
or asymptomatic, although symptomatic pharyngitis does occasionally occur with cervical lymphadenitis. The mode of acquisition is
oral–genital sexual exposure, with fellatio being a more efficient
means of transmission than cunnilingus. In certain female adolescent
populations in the United States, pharyngeal gonorrhea has become as
common as genital gonorrhea. Most cases resolve spontaneously, and
transmission from the pharynx to sexual contacts is rare. Pharyngeal
infection almost always coexists with genital infection. Swabs from the
pharynx should be plated directly onto gonococcal selective media.
Pharyngeal colonization with N. meningitidis needs to be differentiated
from that with other Neisseria species. Because commensal oropharyngeal neisseriae are often resistant to antimicrobials, horizontal gene
transfer between these organisms and N. gonorrhoeae may be important in the development of antimicrobial resistance of N. gonorrhoeae.
Ocular Gonorrhea in Adults Ocular gonorrhea in an adult usually results from autoinoculation of N. gonorrhoeae from an infected
genital site. As in genital infection, the manifestations range from
severe to occasionally mild or asymptomatic disease. The variability in
clinical manifestations may be attributable to differences in the ability
of the infecting strain to elicit an inflammatory response. Infection may
result in a markedly swollen eyelid, severe hyperemia and chemosis,
and a profuse purulent discharge. The massively inflamed conjunctiva
may be draped over the cornea and limbus. Lytic enzymes from the
infiltrating PMNs occasionally cause corneal ulceration and rarely
cause perforation.
Prompt recognition and treatment of this condition are of paramount importance. Gram’s stain and culture of the purulent discharge
establish the diagnosis. Genital cultures also should be performed.
Gonorrhea in Pregnant Women, Neonates, and Children
Gonorrhea in pregnancy can have serious consequences for both the
mother and the infant. Recognition of gonorrhea early in pregnancy
also identifies a population at risk for other STIs, particularly chlamydial infection, syphilis, and trichomoniasis. The risks of salpingitis and
PID—conditions associated with a high rate of fetal loss—are highest
during the first trimester. Pharyngeal infection, most often asymptomatic, may be more common during pregnancy because of altered sexual
practices. Prolonged rupture of the membranes, premature delivery,
chorioamnionitis, funisitis (infection of the umbilical cord stump), and
sepsis in the infant (with N. gonorrhoeae detected in the newborn’s gastric aspirate during delivery) are common complications of maternal
gonococcal infection at term. Other conditions and microorganisms,
including Mycoplasma hominis, Mycoplasma genitalium, Ureaplasma
urealyticum, C. trachomatis, and bacterial vaginosis (often accompanied by infection with Trichomonas vaginalis), have been associated
with similar complications.
1238 PART 5 Infectious Diseases
FIGURE 156-2 Characteristic skin lesions in patients with proven gonococcal bacteremia. The lesions are in various
stages of evolution. A. Very early petechia on finger. B. Early papular lesion, 7 mm in diameter, on lower leg. C. Pustule
with central eschar resulting from early petechial lesion. D. Pustular lesion on finger. E. Mature lesion with central
necrosis (black) on hemorrhagic base. F. Bullae on anterior tibial surface. (Reprinted with permission from TF Murphy,
GI Parameswaran: Clin Infect Dis 49:124, 2009, with permission. © 2009 Infectious Diseases Society of America.)
The most common form of gonorrhea
in neonates is ophthalmia neonatorum,
which results from exposure to infected
cervical secretions during parturition.
Ocular neonatal instillation of a prophylactic agent (e.g., 1% silver nitrate eye
drops or ophthalmic preparations containing erythromycin or tetracycline) prevents ophthalmia neonatorum but is not
effective for its treatment, which requires
systemic antibiotics. The clinical manifestations are acute and usually begin
2–5 days after birth. An initial nonspecific conjunctivitis with a serosanguineous discharge is followed by tense edema
of the eyelids, chemosis, and a profuse,
thick, purulent discharge. Corneal ulcerations that result in nebulae or perforation
may lead to anterior synechiae, anterior staphyloma, panophthalmitis, and
blindness. Infections described at other
mucosal sites in infants, including vaginitis, rhinitis, and anorectal infection,
are likely to be asymptomatic. Pharyngeal
colonization has been demonstrated in
35% of infants with gonococcal ophthalmia, and coughing is the most prominent
symptom in these cases. Septic arthritis
(see below) is the most common manifestation of systemic infection or DGI in
the newborn. The onset usually comes at
3–21 days of age, and polyarticular involvement is common. Sepsis,
meningitis, and pneumonia are seen in rare instances.
Any STI in children beyond the neonatal period raises the possibility of sexual abuse. Gonococcal vulvovaginitis is the most common
manifestation of gonococcal infection in children beyond infancy.
Anorectal and pharyngeal infections are common in these children
and are frequently asymptomatic. The urethra, Bartholin’s and Skene’s
glands, and upper genital tract are rarely involved. All children with
gonococcal infection should also be evaluated for chlamydial infection,
syphilis, and possibly HIV infection.
Gonococcal Arthritis Disseminated gonococcal infection (DGI;
gonococcal arthritis) results from gonococcal bacteremia. In the
1970s, DGI occurred in ~0.5–3% of persons with untreated gonococcal
mucosal infection. The lower incidence of DGI at present is probably
attributable to a decline in the prevalence of particular strains that
are likely to disseminate. Nonetheless, sporadic outbreaks of DGI still
occur in North America. DGI strains resist the bactericidal action of
human serum and generally do not incite inflammation at genital sites,
probably because of limited generation of chemotactic factors. Strains
recovered from DGI cases in the 1970s were often of the PorB.1A
serotype, were highly susceptible to penicillin, and had special growth
requirements—including arginine, hypoxanthine, and uracil—that
made the organism more fastidious and more difficult to isolate.
Menstruation is a risk factor for dissemination, and approximately
two-thirds of cases of DGI are in women. In about half of affected
women, symptoms of DGI begin within 7 days of onset of menses.
Complement deficiencies, especially of the components involved in the
assembly of the membrane attack complex (C5 through C9), predispose to neisserial bacteremia, and persons with more than one episode
of DGI should be screened with an assay for total hemolytic complement activity. DGI is also associated with the use of the complement
C5–blocking monoclonal antibody eculizumab.
The clinical manifestations of DGI have sometimes been classified
into two stages: a bacteremic stage, which is less common today, and a
joint-localized stage with suppurative arthritis. A clear-cut progression
usually is not evident. Patients in the bacteremic stage have higher temperatures, and chills more frequently accompany their fever. Painful
joints are common and often occur together with tenosynovitis and
skin lesions. Polyarthralgias usually include the knees, elbows, and
more distal joints; the axial skeleton is generally spared. Skin lesions
are seen in ~75% of patients and include papules and pustules, often
with a hemorrhagic component (Fig. 156-2; see also Fig. A1-43).
Other manifestations of noninfectious dermatitis, such as nodular
lesions, urticaria, and erythema multiforme, have been described.
These lesions are usually on the extremities and number between 5 and
40. The differential diagnosis of the bacteremic stage of DGI includes
reactive arthritis, acute rheumatoid arthritis, sarcoidosis, erythema
nodosum, drug-induced arthritis, and viral infections (e.g., hepatitis B
and acute HIV infection). The distribution of joint symptoms in reactive arthritis differs from that in DGI (Fig. 156-3), as do the skin and
genital manifestations (Chap. 362).
Suppurative arthritis involves one or two joints, most often the
knees, wrists, ankles, and elbows (in decreasing order of frequency);
other joints occasionally are involved. Most patients who develop
gonococcal septic arthritis do so without prior polyarthralgias or skin
lesions; in the absence of symptomatic genital infection, this disease
cannot be distinguished from septic arthritis caused by other pathogens. The differential diagnosis of acute arthritis in young adults is discussed in Chap. 130. Rarely, osteomyelitis complicates septic arthritis
involving small joints of the hand.
Gonococcal endocarditis, although rare today, was a relatively
common complication of DGI in the preantibiotic era, accounting for
about one-quarter of reported cases of endocarditis. Another unusual
complication of DGI is meningitis.
Gonococcal Infections in HIV-Infected Persons The association between gonorrhea and the acquisition of HIV has been
demonstrated in several well-controlled studies, mainly in Kenya
and Zaire. The nonulcerative STIs enhance the transmission of
HIV three- to fivefold; transmission of HIV-infected immune cells
and increased viral shedding by persons with urethritis or cervicitis may contribute (Chap. 202). HIV has been detected by polymerase chain reaction (PCR) more commonly in ejaculates from
HIV-positive men with gonococcal urethritis than in those from HIVpositive men with nongonococcal urethritis. PCR positivity diminishes
1239CHAPTER 156 Gonococcal Infections
Disseminated gonococcal infection
(N = 102)
Reactive arthritis
(N = 173)
60 50 40 30 20 10 0 10 20 30 40 50 60
Hand and fingers
Wrist
Elbow
Shoulder
Sternal*
Spine and SI†
Hip
Knee
Ankle
Foot and toes
Percent of patients
FIGURE 156-3 Distribution of joints with arthritis in 102 patients with disseminated
gonococcal infection and 173 patients with reactive arthritis. *
Includes the
sternoclavicular joints. †
SI, sacroiliac joint.
twofold after appropriate therapy for urethritis. Not only does gonorrhea enhance the transmission of HIV, but it may also increase the
individual’s risk for acquisition of HIV. A proposed mechanism is the
significantly greater number of CD4+ T lymphocytes and dendritic
cells that can be infected by HIV in endocervical secretions from
women with nonulcerative STIs than in those from women with ulcerative STIs.
■ LABORATORY DIAGNOSIS
A rapid diagnosis of gonococcal infection in men may be obtained
by Gram’s staining of urethral exudates (Fig. 156-1). The detection of
gram-negative intracellular monococci and diplococci is usually highly
specific and sensitive in diagnosing gonococcal urethritis in symptomatic males but is only ~50% sensitive in diagnosing gonococcal cervicitis. Samples should be collected with Dacron or rayon swabs. Part
of the sample should be inoculated onto a plate of modified ThayerMartin or other gonococcal selective medium for culture. It is important to process all samples immediately because gonococci do not tolerate drying. If plates cannot be incubated immediately, they can be held
safely for several hours at room temperature in candle extinction jars
prior to incubation. If processing is to occur within 6 h, transport of
specimens may be facilitated by the use of nonnutritive swab transport
systems such as Stuart or Amies medium. For longer holding periods
(e.g., when specimens for culture are to be mailed), culture media
with self-contained CO2
-generating systems (such as the JEMBEC or
Gono-Pak systems) may be used. Specimens should also be obtained
for the diagnosis of chlamydial infection (Chap. 189).
PMNs are often seen in the endocervix on a Gram’s stain, and an
abnormally increased number (≥30 PMNs per field in five 1000×
oil-immersion microscopic fields) establishes the presence of an
inflammatory discharge. Unfortunately, the presence or absence of
gram-negative intracellular monococci or diplococci in cervical smears
does not accurately predict which patients have gonorrhea, and the
diagnosis in this setting should be made by culture or another suitable
nonculture diagnostic method. The sensitivity of a single endocervical
culture is ~80–90%. If a history of rectal sex is elicited, a rectal wall
swab (uncontaminated with feces) should be cultured. A presumptive
diagnosis of gonorrhea cannot be made on the basis of gram-negative
diplococci in smears from the pharynx, where other Neisseria species
are components of the normal flora.
Several nucleic acid amplification tests (NAATs), including the
Roche COBAS AMPLICOR, Gen-Probe Aptima Combo 2, and BD
ProbeTec ET, are now widely available on semiautomated or fully
automated platforms and are commonly employed diagnostic tests for
gonorrhea. These tests also detect C. trachomatis and are more sensitive than culture for identification of either N. gonorrhoeae or C. trachomatis. The Gen-Probe and BD tests offer the advantage that urine
samples can be tested with a sensitivity similar to or greater than that
obtained when urethral or cervical swab samples are assessed by other
non-NAATs or culture, respectively. A point-of-care NAAT-based test
(Binx io) for gonorrhea and chlamydia with a 30-minute turnaround
time is now approved by the U.S. Food and Drug Administration
(FDA). In MSM, it is important to screen the rectum and pharynx
because screening urine alone will miss the majority of cases. A disadvantage of non-culture-based assays is that N. gonorrhoeae cannot
be grown from the transport systems. Thus, a culture-confirmatory
test and formal antimicrobial susceptibility testing, if needed, cannot
be performed.
Because of the legal implications, the preferred method for the
diagnosis of gonococcal infection in children is a standardized culture. Two positive NAATs, each targeting a different nucleic acid
sequence, may be substituted for culture of the cervix or the urethra as
legal evidence of infection in children. Although nonculture tests for
gonococcal infection have not been approved by the FDA for use with
specimens obtained from the pharynx and rectum of infected children,
NAATs from these sites are preferred for diagnostic evaluation in adult
victims of suspected sexual abuse, especially if the NAATs have been
evaluated by the local laboratory and found to be superior. Cultures
should be obtained from the pharynx and anus of both girls and boys,
the urethra of boys, and the vagina of girls; cervical specimens are not
recommended for prepubertal girls. For boys with a urethral discharge,
a meatal specimen of the discharge is adequate for culture. Presumptive
colonies of N. gonorrhoeae should be identified definitively by at least
two independent methods.
Blood should be cultured in suspected cases of DGI. The use of
Isolator blood culture tubes may enhance the yield. The probability
of positive blood cultures decreases after 48 h of illness. Synovial fluid
should be inoculated into blood culture broth medium and plated onto
chocolate agar rather than selective medium because this fluid is not
likely to be contaminated with commensal bacteria. Gonococci are
infrequently recovered from early joint effusions containing <20,000
leukocytes/μL but may be recovered from effusions containing >80,000
leukocytes/μL. The organisms are seldom recovered from blood and
synovial fluid of the same patient.
TREATMENT
Gonococcal Infections
Treatment failure can lead to continued transmission and the
emergence of antibiotic resistance. The importance of adequate
treatment with a regimen that the patient will adhere to cannot
be overemphasized. Single-dose regimens have been developed
for uncomplicated gonococcal infections. Treatment guidelines for
gonococcal infections from the Centers for Disease Control and
Prevention (CDC) were revised in 2020, and are summarized in
Table 156-1. The third-generation cephalosporin ceftriaxone is
now recommended as the first-line regimen for use at twice the
previous dose (now, 500 mg IM, single dose) based on doubling
of mean inhibitory concentrations (MICs) of current strains compared with MICs 20 years ago. The development of decreased
sensitivity to ceftriaxone throughout the world will require the
development of new effective regimens. Azithromycin, which had
been recommended to provide additional treatment of gonorrhea
(also to include treatment of chlamydial infection) is no longer
recommended as part of a first line regimen. Resistance to azithromycin of U.S. isolates of N. gonorrhoeae, which had been less than
0.6% over a number of years, has increased more than sevenfold to
4.6% in the most recent year in which it was reported. If chlamydial
infection cannot be excluded, concurrent treatment with doxycycline (100 mg orally twice a day for 7 days) is recommended. The
recommendations for uncomplicated gonorrhea apply to HIVinfected as well as HIV-uninfected patients.
1240 PART 5 Infectious Diseases
The currently recommended regimen for the treatment of
uncomplicated gonococcal infection of the urethra, cervix, rectum,
or pharynx (a single IM dose of ceftriaxone) almost always results
in an effective cure. Quinolone-containing regimens are no longer
recommended in the United States as first-line treatment because
of widespread resistance. Rising MICs of cefixime worldwide have
led the CDC to discontinue its recommendation of this agent as
first-line treatment for uncomplicated gonorrhea. Multicenter trials
of treatment for uncomplicated gonorrhea in the United States have
shown ≥99.5% efficacy of two combination regimens and 96% efficacy in one single-agent regimen: gemifloxacin (320 mg, single oral
dose) plus azithromycin (2 g, single oral dose); gentamicin (a single
IM dose of 240 mg or, in individuals who weigh ≤45 kg, 5 mg/kg)
plus azithromycin (2 g, single oral dose), and zoliflodacin (2 or
3 g, single oral dose). At this time, however, none of these regimens
is recommended by CDC as first-line treatment; gentamicin plus
azithromycin is recommended as an alternative regimen.
Co-infection with C. trachomatis occurs frequently; concurrent
treatment with doxycycline (100 mg orally twice daily for 7 days)
is effective against chlamydial infection. Spectinomycin has been
used as an alternative agent for the treatment of uncomplicated
gonococcal infections in penicillin-allergic persons outside the
United States but is not currently available in the United States. Of
note, the limited effectiveness of spectinomycin for the treatment of
pharyngeal infection reduces its utility in populations among whom
such infection is common, such as MSM.
Persons with uncomplicated genital or rectal infections who
receive ceftriaxone or an alternative regimen do not need a test of
cure; however, cultures for N. gonorrhoeae should be performed if
symptoms persist after therapy with an established regimen, and
any gonococci isolated should be tested for antimicrobial susceptibility. Persons with pharyngeal infection should undergo a test of
cure regardless of the treatment regimen, 7–14 days after treatment
to ensure eradication or detection of a possible treatment failure.
Symptomatic gonococcal pharyngitis is more difficult to eradicate
than genital infection. Persons who cannot tolerate cephalosporins
may be treated with an alternative regimen. Treatment with spectinomycin results in a cure rate of ≤52%; persons given spectinomycin should have a subsequent pharyngeal sample cultured early
(3–5 days) following treatment as a test of cure. A single 2-g dose
of azithromycin may be used if the infecting organism is known to
be sensitive or in areas where rates of resistance to azithromycin are
low. Quinolones may be used if the infecting organism is known to
be sensitive. If culture is not readily available and NAAT is positive,
every effort should be made to perform a confirmatory culture. All
isolates from test-of-cure cultures should undergo antimicrobial
susceptibility testing. Because of high rates of reinfection with
N. gonorrhoeae (and C. trachomatis) within 6–12 months, persons
previously treated for gonorrhea should be retested 3 months after
treatment.
Treatments for gonococcal epididymitis and PID are discussed
in Chap. 136. Ocular gonococcal infections in older children and
adults should be managed with a single dose of ceftriaxone combined with saline irrigation of the conjunctivae (both undertaken
expeditiously), and patients should undergo a careful ophthalmologic evaluation that includes a slit-lamp examination.
DGI, particularly the joint-localized stage with suppurative
arthritis, may require higher dosages and longer durations of therapy
(Table 156-1). Hospitalization is indicated if the diagnosis is uncertain, if the patient has localized suppurative arthritis that requires
aspiration, or if the patient cannot be relied on to comply with
treatment. Open drainage is necessary only occasionally—e.g., for
management of hip infections that may be difficult to drain percutaneously. Nonsteroidal anti-inflammatory agents may be indicated
to alleviate pain and hasten clinical improvement of affected joints.
Gonococcal meningitis and endocarditis should be treated in the
hospital with high-dose IV ceftriaxone (1–2 g IV every 12–24 h);
therapy should continue for 10–14 days for meningitis and for at
least 4 weeks for endocarditis. All persons who experience more
than one episode of DGI should be evaluated for complement
deficiency.
■ PREVENTION AND CONTROL
Condoms, if properly used, provide effective protection against the
transmission and acquisition of gonorrhea as well as other infections
that are transmitted to and from genital mucosal surfaces. Spermicidal
preparations used with a diaphragm or cervical sponges impregnated with nonoxynol-9 offer some protection against gonorrhea
and chlamydial infection. However, the frequent use of preparations
that contain nonoxynol-9 is associated with mucosal disruption that
paradoxically may enhance the risk of HIV infection in the event of
exposure. All patients should be instructed to refer sex partners for
evaluation and treatment. All sex partners of persons with gonorrhea
TABLE 156-1 Recommended Treatment for Gonococcal Infections:
Adapted from the 2020 Guidelines for Gonococcal Infection of the
Centers for Disease Control and Prevention
DIAGNOSIS TREATMENT OF CHOICEa
Uncomplicated gonococcal infection of
the cervix, urethra, pharynxb
, or rectum
First-line regimen Ceftriaxone (500 mg IM, single dose)
plus
Doxycycline (100 mg orally twice a day
for 7 days) for treatment of chlamydial
infection if chlamydial infection cannot
be excluded
Alternative regimens if ceftriaxone is
not available
Gentamicin (240 mg IM, single dose)
plus azithromycin (2 g orally as a single
dose)c
Cefixime (800 mg PO, single dose) or
spectinomycin (2 g IM, single dose)d,e
plus
Doxycycline (100 mg orally twice a day
for 7 days) for treatment of chlamydial
infection if chlamydial infection cannot
be excluded
Epididymitis See Chap. 136
Pelvic inflammatory disease See Chap. 136
Gonococcal conjunctivitis in an adult Ceftriaxone (1 g IM, single dose)f
Ophthalmia neonatorumg Ceftriaxone (25–50 mg/kg IV, single
dose, not to exceed 125 mg)
Disseminated gonococcal infectionh
Initial therapyi
Patient tolerant of β-lactam drugs Ceftriaxone (1 g IM or IV q24h;
recommended) or cefotaxime (1 g IV
q8h) or ceftizoxime (1 g IV q8h)
Patients allergic to β-lactam drugs Spectinomycin (2 g IM q12h)d
Continuation therapyj Cefixime (400 mg PO bid)
Meningitis or endocarditis See text for specific recommendationsk
a
True failure of treatment with a recommended regimen is rare and should
prompt an evaluation for reinfection, infection with a drug-resistant strain, or an
alternative diagnosis. b
Ceftriaxone is the most reliable agent recommended for
treatment of pharyngeal infection. c
In vitro synergistic killing of N. gonorrhoeae
of gentamicin plus azithromycin is mild to moderate; azithromycin is for treatment
chlamydial infection, primarily. d
Spectinomycin is unavailable in the United States;
in uncomplicated gonococcal infection it should be used at a higher dose (4 g IM,
single dose) in areas of the world where increased resistance to spectinomycin
exists. e
Spectinomycin may be ineffective for the treatment of pharyngeal
gonorrhea. f
Plus lavage of the infected eye with saline solution (once). g
Prophylactic
regimens are discussed in the text. h
Hospitalization is indicated if the diagnosis
is uncertain, if the patient has the joint-localized stage with suppurative arthritis,
or if the patient cannot be relied on to adhere to treatment. i
All initial regimens
should also include doxycycline (100 mg orally twice a day for 7 days) for treatment
of chlamydial infection if chlamydial infection cannot be excluded; j
gonococcal
therapy should be continued for 24–48 h after clinical improvement begins, at
which time the switch may be made to an oral agent (e.g., cefixime) if antimicrobial
susceptibility can be documented by culture of the causative organism. If no
organism is isolated and the diagnosis is secure, then treatment with ceftriaxone
should be continued for at least 1 week. k
Hospitalization is indicated to exclude
suspected meningitis or endocarditis.
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