Would you please provide advice on when to perform susceptibility testing for group B streptococci isolated from urine specimens, especially in pregnant women with penicillin allergies?

Answer:

Penicillin is the drug of choice for eradicating Group B streptococci in the vagina of pregnant women. Clindamycin and erythromycin are alternative agents for patients unable to tolerate penicillin. Although resistance to penicillin in Group B streptococci has not been noted, resistance to erythromycin and clindamycin among invasive isolates has been reported to be as high as 25% and 8%, respectively. At this time, it is not necessary to test all Group B streptococci from urine; however, testing when specifically requested by a physician may be warranted.

The following articles provide additional information:

1. Andrews, J. I., D. J. Diekema, S. K. Hunter, P. R. Rhomberg, M. A. Pfaller, R. N. Jones, and G. V. Doern. 2000. Group B streptococci causing neonatal bloodstream infection: antimicrobial susceptibility and serotyping results from SENTRY centers in the Western Hemisphere. Am J Obstet Gynecol. 183:859-62.
    
2. Lin, F. Y., P. H. Azimi, L. E. Weisman, J. B. Philips, 3rd, J. Regan, P. Clark, G. G. Rhoads, J. Clemens, J. Troendle, E. Pratt, R. A. Brenner, and V. Gill. 2000. Antibiotic susceptibility profiles for group B streptococci isolated from neonates, 1995-1998. Clin Infect Dis. 31:76-9.