Objective: To determine the efficacy of single-dose benzathine penicillin G in infants at high risk of congenital syphilis.
Design: Randomised study comparing benzathine penicillin with no therapy.
Setting: Peninsula Maternal and Neonatal Service, Cape Town.
Subjects: Asymptomatic infants born to mothers with untreated syphilis whose VDRL titre was 32 or more.
Outcome measures: The number of cases of congenital syphilis was determined by results of IgM Western blots and follow-up VDRL titres.
Results and conclusions: Of 8 patients followed up in the non-treatment group, 4 had congenital syphilis while 0/11 had the disease (P = 0.035) in the group receiving benzathine penicillin. Although the exact failure rate is unknown, benzathine penicillin is effective in preventing symptomatic congenital syphilis when administered to high-risk newborns.