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Streptococcus Group B Infections Treatment & Management

  • Author: Christian J Woods, MD, FCCP; Chief Editor: Michael Stuart Bronze, MD  more...
Updated: Oct 20, 2015

Medical Care

Group B streptococci are uniformly sensitive to penicillin and ampicillin. Although resistance to penicillin or ampicillin has not be documented, some isolated have shown minimum inhibitory concentrations (MICs) approaching the upper limits of susceptibility for some of the beta-lactam agents.[5] Group B streptococci have never been as exquisitely sensitive to penicillin as group A beta-hemolytic streptococci; therefore, the initial therapy for group B streptococcal infection has always been high-dose parenteral penicillin or ampicillin.

Penicillin or ampicillin plus an aminoglycoside has demonstrated synergy but has not been shown to provide a better clinical outcome than penicillin or ampicillin alone. Testing for aminoglycoside sensitivity is important because synergy is not observed if the organism is not sensitive to aminoglycosides. Keep in mind that given group B streptococcal isolate can be resistant to one aminoglycoside and sensitive to another.

While clindamycin and erythromycin were at one time uniformly active against group B streptococci, resistance has been increasing. One large study that examined the susceptibility patterns of over 4800 group B streptococcal isolates found that 32% were resistant to erythromycin, 15% were resistant to clindamycin, and 99% of clindamycin-resistant strains were also resistant to erythromycin.[5] As a result, sensitivity testing is important before these agents are used. Oral clindamycin remains an excellent agent to follow a course of parenteral therapy for bone, soft-tissue, and lung infections if the isolate is susceptible.

Because of possible resistance with clindamycin, vancomycin remains the initial treatment of choice for group B streptococcal infection in patients who are allergic to penicillin. Penicillin, ampicillin, or vancomycin remains the treatment of choice for endocarditis. While vancomycin may be adequate in group B streptococcal meningitis in patient who are allergic to penicillin, skin testing and desensitization for penicillin therapy might be considered. Penicillin has not been demonstrated to be superior to vancomycin for group B streptococcal endocarditis.

While fluoroquinolones appear to have efficacy against isolates of group B streptococci, resistance to fluoroquinolones has recently been reported.[10]

Similarly, linezolid, a new antibiotic with efficacy for aerobic gram-positive cocci, should have activity against group B streptococci. It is available in parenteral or oral form. However, no clinical studies have evaluated linezolid in group B streptococcal infections.


Surgical Care

Surgical opinion and intervention is important.

Pneumonia may require empyema drainage.

Endocarditis, bacteremia, and sepsis may require heart valve replacement.

Soft-tissue infection, septic arthritis, osteomyelitis, discitis, and epidural abscess often require surgery combined with parenteral antibiotics for cure.

Necrotizing fasciitis and septic arthritis are surgical emergencies.

Epidural abscess may require emergency surgery.

Urinary tract infection and pelvic abscess may require relief of genitourinary obstruction and abscess drainage for cure.



Group B streptococcal infection may require various consultations for an optimal outcome. An infectious disease specialist is often helpful in choosing the antibiotic and duration of therapy. Appropriate surgical support is critical for a good outcome.

Pneumonia may require a pulmonologist or surgeon for empyema drainage.

Bacteremia, endocarditis, and line-related sepsis may require a cardiovascular surgeon for valve replacement.

Soft-tissue infection, osteomyelitis, epidural abscess, discitis, and arthritis require a rheumatologist for arthrocentesis and an orthopedic surgeon or neurosurgeon for possible surgical opinion and intervention.

Urinary tract infection or pelvic abscess may require a urologist or gynecologist for surgical opinion and possible relief of obstruction and abscess drainage.

Contributor Information and Disclosures

Christian J Woods, MD, FCCP Associate Program Director for Internal Medicine, Associate Program Director for Pulmonary/Critical Care, Associate MICU Director, Attending in Infectious Diseases/Pulmonary/Critical Care, MedStar Washington Hospital Center

Christian J Woods, MD, FCCP is a member of the following medical societies: American College of Chest Physicians, American College of Physicians-American Society of Internal Medicine, American Medical Association, American Society for Microbiology, American Thoracic Society, Infectious Diseases Society of America

Disclosure: Serve(d) as a speaker or a member of a speakers bureau for: Cubist Pharmaceuticals.


Charles S Levy, MD Associate Professor, Department of Medicine, Section of Infectious Disease, George Washington University School of Medicine

Charles S Levy, MD is a member of the following medical societies: American College of Physicians, Infectious Diseases Society of America, Medical Society of the District of Columbia

Disclosure: Nothing to disclose.

Specialty Editor Board

Francisco Talavera, PharmD, PhD Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Received salary from Medscape for employment. for: Medscape.

John L Brusch, MD, FACP Assistant Professor of Medicine, Harvard Medical School; Consulting Staff, Department of Medicine and Infectious Disease Service, Cambridge Health Alliance

John L Brusch, MD, FACP is a member of the following medical societies: American College of Physicians, Infectious Diseases Society of America

Disclosure: Nothing to disclose.

Chief Editor

Michael Stuart Bronze, MD David Ross Boyd Professor and Chairman, Department of Medicine, Stewart G Wolf Endowed Chair in Internal Medicine, Department of Medicine, University of Oklahoma Health Science Center; Master of the American College of Physicians; Fellow, Infectious Diseases Society of America

Michael Stuart Bronze, MD is a member of the following medical societies: Alpha Omega Alpha, American Medical Association, Oklahoma State Medical Association, Southern Society for Clinical Investigation, Association of Professors of Medicine, American College of Physicians, Infectious Diseases Society of America

Disclosure: Nothing to disclose.

Additional Contributors

Pranatharthi Haran Chandrasekar, MBBS, MD Professor, Chief of Infectious Disease, Program Director of Infectious Disease Fellowship, Department of Internal Medicine, Wayne State University School of Medicine

Pranatharthi Haran Chandrasekar, MBBS, MD is a member of the following medical societies: American College of Physicians, American Society for Microbiology, International Immunocompromised Host Society, Infectious Diseases Society of America

Disclosure: Nothing to disclose.


The authors and editors of Medscape Reference gratefully acknowledge the contributions of previous coauthor Mohamad Ossiani, MD, to the development and writing of this article.

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