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However, in 2012, the CDC no longer recommended cefixime as a first-line regimen

because of concerns about declining cefixime susceptibility among urethral N.

gonorrhoeae isolates in the United States during 2006 to 2011.

19 Other oral

cephalosporins, such as cefpodoxime and cefuroxime, are not recommended because

of inferior efficacy and less favorable pharmacodynamics; however, they are FDA

approved to treat uncomplicated N. gonorrhoeae.

Fluoroquinolones

Fluoroquinolones have been routinely used since the 1990s for the treatment of

gonorrhea; however, the GISP has continuously documented fluoroquinolone

resistance in N. gonorrhoeae isolates, which has necessitated changes in the CDC

Sexually Transmitted Disease treatment guidelines (Fig. 72-3). Because of this

increased resistance, the CDC no longer recommends ciprofloxacin, levofloxacin,

ofloxacin, or other fluoroquinolones for the treatment of gonorrhea. This

recommendation also extends to the treatment of gonorrhea-associated conditions,

such as PID.

2

,

20

Prescribing Patterns

The CDC’s 2013 Sexually Transmitted Disease Surveillance Program observed that

96.9% of treated patients received ceftriaxone 250 mg. The number of those treated

with cefixime decreased from 5.3% in 2011 to 0.02% in 2013.

4 This decrease in

cefixime use was expected as CDC recommendations to avoid use of cefixime at any

dose as first-line therapy was issued in 2012. Other most prescribed medications,

followed in order by ceftriaxone, azithromycin, “other less frequently used drugs,”

and cefixime (Fig. 72-4). Dual therapy with azithromycin or doxycycline was

prescribed in 95.4% and 4% of those treated with ceftriaxone, respectively.

4

CASE 72-1, QUESTION 7: How should D.S.’s urethritis be treated? Because C.S. is totally asymptomatic

and the results of her cultures are pending, should she be treated empirically? If so, what drug(s) would you

recommend?

Because D.S. has gonococcal infection limited to the urethra (uncomplicated), a

few treatment regimens are possible, as outlined in Case 72-1, Question 6.

Ceftriaxone is the preferred treatment, with cefixime as an alternative, only if

ceftriaxone is not available. Quinolones should be avoided because of increased

resistance in N. gonorrhoeae and because D.S.’s infection was likely obtained in the

Philippines, where quinolone resistance occurs in more than half of all isolates.

20

,

24

Patients with gonorrhea may also be coinfected with Chlamydia and therefore

presumptive cotreatment with azithromycin 1 g PO as a single dose could be initiated

if coinfection is suspected.

19

,

25 Although single-dose azithromycin 2 g monotherapy

has been used to treat concurrent gonorrhea and Chlamydia, it is more expensive and

poorly tolerated because of increased gastrointestinal (GI) side effects and may lead

to macrolide-resistant N. gonorrhoeae, or treatment failure.

2

Sexual Partners

C.S. also should be treated even though she appears asymptomatic. All partners who

have had sexual exposure to patients with gonorrhea within 60 days should be

treated. If the patient has not been sexually active for 60 days, the most recent sexual

partner should be treated. This is especially true when the partner is pregnant

because gonorrhea during pregnancy is associated with chorioamnionitis and

prematurity, as well as neonatal infection. Pregnant women can be treated safely with

cephalosporins and azithromycin for gonorrhea and Chlamydia.

p. 1509

p. 1510

Figure 72-3 Gonococcal Isolate Surveillance Project (GISP)—Percent of Neisseria gonorrhoeae isolates with

resistance or intermediate resistance to ciprofloxacin, 1990 to 2009. Source: Centers for Disease Control and

Prevention. 2009 Sexually Transmitted Disease Surveillance. Atlanta, GA: US Dept of Health and Human

Services; 2010.

Follow-Up

CASE 72-1, QUESTION 8: How does one determine whether the drug therapy of gonorrhea has been

effective in D.S. and C.S.?

If recommended therapies are used for treatment of uncomplicated gonorrhea, a

test-of-cure is not necessary for either C.S. or D.S. because cure rates are close to

100%.

2 However, a test-of-cure should be done 14 days after treatment in those with

pharyngeal infection treated with an alternative treatment regimen.

2

If symptoms

persist in D.S., who was treated with ceftriaxone, cultures should be done to

determine antibiotic susceptibility, and to rule out other causes of urethritis.

Antibiotic-Resistant Neisseria gonorrhoeae

CASE 72-1, QUESTION 9: D.S. states that he was treated with penicillin in the past for a gonococcal

infection. Why are penicillins not prescribed routinely today?

Failure of penicillin to eradicate the gonococcus can be the result of plasmid (e.g.,

PPNG) or chromosomally mediated resistant Neisseria gonorrhea (CMRNG)

antibiotic resistance. PPNG contain plasmids, which determine the production of

lactamase, an enzyme that hydrolyzes the lactam ring of penicillin G or ampicillin.

Chromosomally mediated resistance does not involve β-lactamase production and

often is associated with increased resistance to other β-lactams. The clinical

significance of CMRNG is questionable because serum levels of approved

antibiotics are achieved far above the minimum inhibitory concentration, such that

treatment failure is unlikely. However, to date, CMRNG remain largely susceptible

to ceftriaxone. High-level tetracycline resistance is defined by gonococci that carry

plasmid-encoded resistance to 16 g/mL or more of tetracycline. These strains are

known as TRNG. Although not of major concern in the United States, development of

resistance to alternative therapies is a continuing concern.

The first cases of PPNG infection were reported in the United States in 1976.

PPNG are especially prevalent in Southeast Asia, the Far East, and West Africa,

where the prevalence often exceeds 50%. In the United States, the percent of PPNG

strains reached a peak of about 11% in 1991; since then, cases have steadily declined

to 0.4% in 2007, according to the CDC’s GISP (Fig. 72-2).

26 Strains of TRNG were

first identified in 1985, but fortunately most TRNG isolates still are sensitive to βlactam antibiotics. The use of tetracycline was officially abandoned by the CDC in

1985 and penicillin was abandoned in 1987. In the late 1990s, the number of TRNG

and PPNG plus TRNG cases plateaued at about 5% and 1%, respectively. Therefore,

because approximately 21% of gonococcal isolates are resistant to tetracycline

and/or penicillin within the United States, it is not acceptable to use these agents in

the initial management of uncomplicated genital gonorrhea; IM ceftriaxone remains

the drug of choice. Antibiotic susceptibility testing is recommended in cases of

persistent infection after treatment.

QRNG was first reported in 1990 and was reported to be 0.2% of isolates in the

continental United States.

3

,

17

In the 2013 GISP report, 11% of isolates from

Honolulu, Hawaii, were QRNG, whereas among California sites, 31.8% to 44.4% of

isolates were QRNG.

27 N. gonorrhoeae resistance to quinolones has increased almost

every year since reporting began in 1990 and has become widespread in the United

States, resulting in the CDC recommending against using quinolones for the treatment

of gonococcal or related conditions (e.g., PID) acquired in the United States.

12

,

20

In

2013, 16.1% of all isolates collected by the GISP demonstrated resistance to

ciprofloxacin.

4 Resistance to fluoroquinolones is associated with mutations of GyrA

and is commonly identified in strains that produce β-lactamase and strains exhibiting

chromosomally mediated resistance to penicillin and tetracycline.

28 N. gonorrhoeae

strains may therefore exhibit decreased susceptibility or complete resistance to the

recommended dose of quinolones, and the clinical importance of strains with

decreased susceptibility is unknown.

29

p. 1510

p. 1511

Figure 72-4 Gonococcal Isolate Surveillance Project (GISP)—Drugs used to treat gonorrhea in GISP participants,

1988 to 2013. Note: For 2013, “Other” includes no therapy (0.9%), azithromycin 2 g (1.7%), and other less

frequently used drugs (<0.1%).

D.S. was likely infected with N. gonorrhoeae in the Philippines, and QRNG is

highly likely; thus, an appropriate cephalosporin antibiotic such as IM ceftriaxone

should be recommended. If he had been initially treated with ceftriaxone, the

expectation would be that he would be free of gonococcal infection within 3 days. To

date, ceftriaxone-resistant strains of N. gonorrhoeae have not been reported in the

United States, but GISP data has documented decreased cefixime susceptibility

among urethral N. gonorrhoeae isolates.

19

Anorectal and Pharyngeal Gonorrhea

EPIDEMIOLOGY

CASE 72-2

QUESTION 1: M.B. is a 24-year-old, sexually active, homosexual man with a 2-month history of perianal

itching, painful defecation, constipation, a bloody mucoid rectal discharge, and a sore throat. Sigmoidoscopy

revealed rectal mucosal inflammation but no apparent ulcers or fissures. Stool examination for parasites was

negative and a Venereal Disease Research Laboratory (VDRL) test was nonreactive. Both rectal and

pharyngeal cultures revealed N. gonorrhoeae. How does gonorrhea in homosexual men compare with

gonorrhea in heterosexual men?

Rectal infection occurs rarely in strictly heterosexual men, whereas in the male

homosexual population, anorectal (25%) and pharyngeal (10%–25%) gonococcal

infections occur more often.

8

,

30 Because pharyngeal

30

,

31 and anorectal gonococcal

infections are often asymptomatic, a large reservoir of carriers in the homosexual

male population may exist and annually screening should be done if they have

engaged in receptive oral or anal intercourse in the preceding year. By comparison,

very few urethral gonococcal infections are asymptomatic. In addition, data indicate

that pharyngeal infections may be an important source of urethral gonorrhea in

homosexual men, spread by fellatio.

30

,

32

SIGNS AND SYMPTOMS

CASE 72-2, QUESTION 2: Are M.B.’s signs and symptoms consistent with gonorrhea?

Rectal gonorrhea produces the syndrome of proctitis with anorectal pain,

mucopurulent anorectal discharge, constipation, tenesmus, and anorectal bleeding.

The differential diagnosis of proctitis in the homosexual male includes rectal

infection with N. gonorrhoeae, C. trachomatis, HSV, and syphilis. Proctitis, limited

to the distal rectum, should be differentiated from proctocolitis, which is often

caused by Shigella species, Campylobacter species, or Entamoeba histolytica in

homosexual men. The incidence of rectal gonorrhea and Chlamydia has risen

dramatically since 1996.

33 Rectal Chlamydia is often asymptomatic and observed

more often than gonorrhea, necessitating testing for both pathogens.

34 Although

pharyngeal gonorrhea is often asymptomatic, a review of system and physical exam

may reveal a sore throat, pharyngeal exudates, or cervical lymphadenitis.

CASE 72-2, QUESTION 3: How should M.B.’s diagnosis be managed?

TREATMENT

The treatment of choice for patients such as M.B. with anorectal or pharyngeal

gonorrhea is ceftriaxone 250 mg IM as a single dose (Table 72-1).

12 Azithromycin

should also be given to treat possible coexisting rectal chlamydial infection. Patients,

such as M.B., with either anorectal or pharyngeal gonorrhea should be advised to

avoid further unprotected sexual activity and should be counseled and tested for

infection with HIV.

CASE 72-2, QUESTION 4: What are the alternative regimens for patients with isolated anal or pharyngeal

gonorrhea?

Patients with anorectal gonorrhea alone should be treated with ceftriaxone. Oral

cefixime is a recommended alternative, but it should not be used as a first-line agent.

As with urogenital

p. 1511

p. 1512

infections, alternative regimens for isolated anorectal infection include a singledose cephalosporin regimen, such as ceftizoxime. Because spectinomycin is

unavailable, patients with anorectal gonorrhea, who are allergic to penicillin or

cephalosporins, should be desensitized before treatment is initiated. Patients with

gonococcal infections of the pharynx should be treated with ceftriaxone; however,

infections of this nature are more difficult to eradicate than infections at urogenital

and anorectal sites. Treatment for gonorrheal infections at these sites should also be

treated with azithromycin for presumptive Chlamydial coinfection.

19

PREVENTION

CASE 72-2, QUESTION 5: What measures have been used to prevent the sexual transmission of infection?

Condoms, when used properly, seem to provide a high degree of protection against

the acquisition and transmission of STDs.

2

,

35 Previous studies indicated that the use

of the spermicide nonoxynol-9 had activity against gonorrhea and Chlamydia;

however, in light of recent evidence suggesting that nonoxynol-9 might actually

increase the risk of acquiring HIV and other STDs, the FDA currently requires

manufacturers of nonoxynol-9 products to include a warning statement on the

product’s label that it does not protect against HIV or other STDs.

12

,

36 Topical

antibacterial agents, urinating, and washing after intercourse are of little value in

preventing the transmission of STDs. Douching may increase the risk of other STDs,

such as trichomoniasis.

37

The prophylactic administration of antibiotics immediately before or soon after

sexual intercourse is not recommended owing to increased costs and antimicrobial

resistance. Use of rapid, specific tests and empiric symptomatic management

enhances detection and treatment of gonorrhea.

PELVIC INFLAMMATORY DISEASE

The term PID refers to a variety of inflammatory disorders of the upper female

reproductive tract. This term does not denote the primary infection site (the fallopian

tubes) nor the causative microorganisms. PID also has been used to connote an

infection that occurs acutely when either vaginal or cervical micro-organisms

traverse the sterile endometrium and ascend to the fallopian tubes. Acute salpingitis

may also be used to describe an acute infection of the fallopian tubes. Therefore, the

terms PID and salpingitis are used interchangeably in this discussion to denote an

acute infection involving the fallopian tubes.

PID affects approximately 1 million women annually in the United States.

38

However, the National Disease and Therapeutic Index (NDTI) estimates that from

2002 to 2012, the number of initial visit to physicians for PID for women aged 15 to

44 decreased 39.8%.

4 Many cases of acute PID occur by sexual transmission,

especially in young women 16 to 24 years, who are more likely to have multiple

sexual partners.

39 Risk factors for the development of PID include unprotected sexual

intercourse before age 15, douching, BV, sex while menstruating, and smoking.

40

It is

unclear whether an intrauterine device (IUD) increases the risk of PID, but it may be

prudent to avoid placement when the patient has chlamydial or gonococcal

cervicitis.

41 Two-thirds of PID cases resulting in infertility are asymptomatic, and up

to one-third are incorrectly diagnosed owing to low specificity of diagnostic

techniques. In the United States, infertility occurs in about 12.1% of women after the

first episode of PID.

42 The estimated costs for treatment of PID and its sequelae

exceeds $4.2 billion annually.

38

Etiology

Most cases of PID are caused by C. trachomatis and N. gonorrhoeae. Some

microorganisms that make up the vaginal flora are also associated with PID,

including Gardnerella vaginalis, H. influenzae, and Streptococcus agalactiae.

Mycoplasma hominis, Ureaplasma urealyticum, M. genitalium, and cytomegalovirus

(CMV) have also been associated with PID, but a causative role is unclear.

12 Up to

70% of cases may be polymicrobial and include M. genitalium and BV.

43 Facultative

enteric gram-negative bacilli and a variety of anaerobic bacteria have also been

isolated from the upper genital tract of up to 70% of women with acute PID.

43

Women diagnosed with acute PID should be tested for C. trachomatis and N.

gonorrhoeae using NAAT and screened for HIV.

2

Signs and Symptoms

The variations in presentation and nonspecific signs and symptoms of PID make it a

complex disease to diagnosis. The onset of symptoms of abdominal pain attributable

to PID caused by either gonococci or chlamydia often occurs soon after the menstrual

period. Symptoms of PID, if present, are often nonspecific, which can create a delay

in or failure of diagnosis. Vaginal discharge, menorrhagia, dysuria, and dyspareunia

are commonly associated with PID. Pelvic examination findings include cervical

motion tenderness, uterine tenderness, or adnexal tenderness. Temperatures greater

than 101°F, abnormal cervical or vaginal mucopurulent discharge, white blood cells

(WBC) on saline microscopy of vaginal secretions, elevated erythrocyte

sedimentation rate, an elevated C-reactive protein, or laboratory documentation of

cervical infection with N. gonorrhoeae or C. trachomatis support a diagnosis of PID.

2

Clinical diagnosis has sensitivity for PID of about 65% to 90%, whereas

laparoscopy and a newer technique, transvaginal Doppler ultrasound, are about

100% specific, resulting in the combination of laparoscopy and clinical impression

serving as the gold standard.

2

,

44

,

45 Unfortunately, laparoscopy and Doppler ultrasound

are costly and often not readily available for acute cases and they are not diagnostic

for endometritis; thus, clinical impression is critical. A key to reducing the incidence

of PID may be through active screening of Chlamydia in young, sexually active

women.

46

,

47

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