Syphilis therapy during pregnancy is given to eradicate maternal infection and to prevent or treat congenital syphilis. Parenteral penicillin G remains the preferred treatment for all stages of syphilis during pregnancy (Table 65-1). During pregnancy, authorities recommend that a second dose of benzathine penicillin G be given 1 week after the initial dose. Such treatment is also given for women with concomitant HIV infection (Workowski, 2015).
Benzathine penicillin G is highly efective for early maternal infection. In a study of 340 pregnant women so treated, Alexander and associates (1999) reported six cases-1.8 percent-of congenital syphilis. Four of these six neonates were from a group of75 women with secondary syphilis. The other two were identified in those delivered from a group of 102 women with early latent syphilis. Congenital syphilis was generally confined to neonates of women treated ater 26 weeks and is likely related to the duration and severity of fetal infection. Sheield and coworkers (2002b) reported that high maternal serological titers, preterm delivery, and delivery shortly ater antepartum therapy are all risks for failure of maternal treatment to prevent neonatal infection.
here are no proven alternatives to penicillin therapy during pregnancy. Erythromycin and azithromycin may be curative for the mother, but because of limited transplacental passage, these drugs do not prevent all congenital disease (Berman, 2004; Wendel, 1988; Zhou, 2007). Moreover, in several countries,
TABLE 65-1. Recommended Treatment for Pregnant Women with Syphilis
G, 2.4 million units as a single injection-some recommend a second
More than l-year durationb Benzathine penicillin G, 2.4 million units intramuscularly weekly for three doses aprimary, secondary, early latent syphilis of less than duration.
bLatent syphilis of unknown or more than 1-year duration; tertiary syphilis. Missed doses are not acceptable for pregnant women, and those who miss any dose of therapy must repeat the full course of therapy.
Data from Workowski, 201r5.
macrolide-resistant strains of T pallidum are now prevalent (Stamm, 2015). Cephalosporins may prove useful, but data are limited (Liang, 2016). Tetracyclines, including doxycycline, are efective but generally not recommended during pregnancy, because of the risk for fetal deciduous-teeth discoloration.
All women with syphilis are ofered counseling and testing for HIV and other STDs. Following syphilis treatment, serological testing to detect treatment failures is done at 3 to 6 months and usually confirms a fourfold drop in VDRL or RPR titers. During pregnancy, serological titers can be checked monthly in women at high risk for reinfection (Workowski, 2015).
In some instances, a woman may present without symptoms but describes recent sexual contact with a person who has been diagnosed with syphilis. She should be evaluated clinically and serologically. If her partner is diagnosed and their sexual contact occurred within the preceding 90 days, the gravida is treated presumptively for early syphilis, even if serological test results are negative. his accounts for early infection but before seroconversion. If contact was earlier than 90 days ago, treatment is based on serological results (Workwoski, 2015).
Women with a history of penicillin allergy should have either an oral stepwise penicillin-dose challenge or skin testing performed to confirm the risk of immunoglobulin E (IgE)mediated anaphylaxis. If conirmed, penicillin desensitization, shown in Table 65-2, is recommended and then followed by benzathine penicillin G treatment (Wendel, 1985).