New findings I selected for this Update affect the management of 4 common and potentially serious clinical problems: acute cystitis, gonorrhea and chlamydia infection, chorioamnionitis, and varicella.
- A comparison of amoxicillin-clavulanic acid vs ciprofloxacin for uncomplicated lower urinary tract infections yielded surprising results, and more evidence on E coli’s resistance to antibiotics.
- Sexual partners of women with gonorrhea or chlamydia are more likely to receive appropriate treatment if it is offered by the women themselves or by the women’s caregivers.
- Short-course therapy for chorioamnionitis had a very high cure rate, equal to the traditional course, and furthers the possibility of shorter hospitalizations and cost savings without compromising outcomes.
- The CDC’s 1995 call for universal childhood vaccination for varicella has already sharply reduced varicella-related mortality in adults; still, we must determine immunity in our reproductive-age patients.
Acute cystitis: Ciprofloxacin prevails in E coli skirmish
Hooton TM, Scholes D, Gupta K, Stapleton AE, Roberts PL, Stamm WE. Amoxicillin-clavulanate vs ciprofloxacin for the treatment of uncomplicated cystitis in women: a randomized trial. JAMA. 2005;293:949–955.
Amoxicillin-clavulanate was not as effective as ciprofloxacin even in women who were infected with bacteria sensitive to amoxicillin-clavulanate.
A total of 320 nonpregnant women, aged 18 to 45 years, with uncomplicated acute cystitis were treated for 3 days with either oral amoxicillin-clavulanate (500 mg/125 mg twice daily) or oral ciprofloxacin (250 mg twice daily). Two weeks after treatment, 95% of women treated with ciprofloxacin were clinically cured, compared with only 76% of women treated with amoxicillin-clavulanate (P<.001).
Start with ciprofloxacin
The difference in outcome was attributed to a marked difference in vaginal colonization with the single most common pathogen in acute cystitis—Escherichia coli—at the 2-week follow-up (45% in the amoxicillinclavulanate group vs 10% in the ciprofloxacin group, P<.001).
Even though successful treatment of cystitis usually is possible with short courses (3–7 days) of oral antibiotics, persistent and recurrent infections may occur and usually are related to persistent vaginal colonization with E coli.
Treatment may require an extended course of oral antibiotics.
Initial selection of an antibiotic for acute cystitis is empiric and should be based on probable susceptibility of the dominant uropathogens. For many years, the typical initial antibiotic has been ampicillin.
E coli resistance. Now, however, more than a third of E coli strains, as well as most strains of K pneumoniae, are resistant to ampicillin. Therefore, ampicillin no longer should be used for the empiric treatment of cystitis.1
Surprising results
In theory, amoxicillin-clavulanate should have enhanced activity against E coli and other enteric organisms.
Therefore, these findings are surprising. The outcome with amoxicillin-clavulanate was inferior to that of ciprofloxacin, even in women who seemingly had susceptible uropathogens.
Based on this study, ciprofloxacin clearly is a more effective (and less expensive) empiric treatment in nonpregnant women.
In gravidas, start with nitrofurantoin
Ciprofloxacin is not appropriate for treatment of cystitis or asymptomatic bacteriuria in pregnant women. The quinolone antibiotics may cause injury to the developing cartilage of the fetus and are contraindicated in pregnant and lactating women, and in children younger than 17 years.1
What, then, is the most appropriate choice for treatment of uncomplicated cystitis during pregnancy?
One reasonable selection is oral trimethoprim-sulfamethoxazole, double-strength, twice daily. However, increasing resistance of E coli to this antibiotic has been documented recently.2,3
Therefore, a better choice is nitrofurantoin monohydrate macrocrystals, 100 mg twice daily.4 One organism that is not susceptible to nitrofurantoin is Proteus. When this organism is suspected, use trimethoprim-sulfamethoxazole.
Follow-up is a must
Because persistent and recurrent infections are common, patients should be followed with urine dipstick assessment or urine culture to be certain that the infection is resolved.
Follow-up is particularly important when infected women are pregnant, because of the risk of ascending infection leading to preterm labor, sepsis, or acute respiratory disease syndrome.
Treat sex partners, sight-unseen?
Golden MR, Whittington WL, Handsfield HH, et al. Effect of expedited treatment of sex partners on recurrent or persistent gonorrhea or chlamydial infection. N Engl J Med. 2005;352:676–685.
Providing a separate prescription for the partner(s) resulted in a 24% decrease in the frequency of persistent or recurrent infection.
Almost 2,000 men and women with uncomplicated gonorrhea or chlamydia infection were included in this study of expedited treatment compared with standard referral. In the standard referral group, investigators treated 931 patients and referred their sex partners to other physicians or facilities for evaluation and treatment. In the expedited treatment group, 929 patients were treated and also were provided with antibiotics to give to their partners. The partners of patients who were unwilling to do so were contacted and treated by the investigators.